F1 connectivity options in integrated access and backhaul handover scenarios

Abstract

Methods, systems, and devices for wireless communication are described. An integrated access and backhaul (IAB) node may have a radio resource control (RRC) connection with a first central unit of a first network node. The IAB node may receive an indication that the IAB node will establish an IAB node-to-central unit connection (e.g., an F1 circuitous connection) with a second central unit of a second network node via the RRC connection between the IAB node and the first network node. The indication may be associated with a handover between the first network node to the second network node, where the first network node may be a source node and the second network node may be a target node, or vice versa. The IAB node may communicate with the second network node via the IAB node-to-central unit connection using the RRC connection between the IAB node and the first network node.

Description

[0001] Cross-references

[0002] This application claims priority to U.S. Patent Application No. 18 / 331,116, filed on June 7, 2023, by AKL et al., entitled “F1 CONNECTION OPTIONS IN INTEGRATED ACCESS AND BACKHAUL HANDOVER SCENARIOS” and U.S. Provisional Patent Application No. 63 / 351,305, filed on June 10, 2022, by AKL et al., entitled “F1 CONNECTION OPTIONS IN INTEGRATED ACCESS AND BACKHAUL HANDOVER SCENARIOS”; each of which is assigned to the assignee of this application. U.S. Provisional Patent Application No. 63 / 351,305 is expressly incorporated herein by reference in its entirety. Background Art

[0003] The following relates to wireless communications, including an integrated access and backhaul (IAB) handover scenario.

[0004] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcast, etc. These systems may be able to support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include fourth generation (4G) systems (such as long term evolution (LTE) systems, advanced LTE (LTE-A) systems, or LTE-A Pro systems) and fifth generation (5G) systems (which may be referred to as new radio (NR) systems). These systems may use techniques such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multiple access communication system may include one or more base stations, each of which supports wireless communication of communication devices, which may be referred to as user equipment (UE). Summary of the invention

[0005] The described technology relates to improved methods, systems, devices and apparatuses for supporting F1 connection options in integrated access and backhaul (IAB) handover scenarios. For example, the described technology provides an improved method for supporting user equipment (UE) during an IAB handover procedure. Specifically, the technology described herein supports an F1 (e.g., an IAB node to central unit connection) connection at an IAB node during an IAB handover procedure to maintain a radio link at the UE during the IAB handover procedure. In order to maintain an F1 connection to serve the UE during the IAB handover procedure, one or more logical channels (e.g., a radio resource control (RRC) channel, a non-access stratum (NAS) channel, an existing F1 connection) may be utilized to forward an F1 container between the UE and a base station and establish a "detour" F1 path. In some cases, an F1 connection may be established with a target base station in a make-before-break manner, or an F1 connection may be established with a source base station in a make-before-break manner. For example, an IAB node may establish an RRC connection with a first central unit of a first network node (e.g., a first base station, a first donor base station). The IAB node may receive an indication or otherwise determine to establish an F1 connection with a second central unit of a second network node (e.g., a second base station, a second donor base station) via the RRC connection between the IAB node and the first network node. Subsequently, the IAB node may communicate with the second network node via the F1 connection using the RRC connection between the IAB node and the first network node.

[0006] In some cases, a first network node (e.g., a donor base station) that forwards an F1 container (e.g., a non-F1 called end base station) may establish an RRC connection with an IAB node, wherein the RRC connection may be located between a first central unit of the first network node and the IAB node. The first network node may identify and in some cases may send first control information to the IAB node, the first control information indicating that the IAB node will establish an F1 connection with a second central unit of a second network node (e.g., an F1 called end base station) via the RRC connection between the IAB node and the first network node. The first network node may relay (e.g., forward) traffic via the F1 connection between the second network node and the IAB node using the RRC connection between the IAB node and the first network node.

[0007] In some cases, the second network node (e.g., donor base station, F1 called end base station) may receive an indication or otherwise determine that the IAB node is handed over from the first network node to the second network node, or vice versa. The second network node may determine an address based on the indication, which is used to forward the service via the first network node using the F1 connection between the central unit of the second network node and the IAB node. The second network node may send the service to the address. In some cases, the first network node may be the source base station, and the second network node may be the target base station (such as in a connect-before-break scenario). In some cases, the first network node may be the target base station, and the second network node may be the source base station (such as in a connect-before-break scenario).

[0008] A method for wireless communication at an IAB node is described. The method may include: establishing a radio resource control connection with a first central unit of a first network node; receiving an indication from the first network node that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and communicating with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node.

[0009] An IAB node for wireless communication (e.g., an apparatus for wireless communication at an IAB node) is described. The IAB node may include a memory and at least one processor, the at least one processor being coupled to the memory. The at least one processor may be configured to: establish a radio resource control connection with a first central unit of a first network node; receive an indication from the first network node that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and communicate with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node.

[0010] Another apparatus for wireless communication at an IAB node is described. The apparatus may include: means for establishing a radio resource control connection with a first central unit of a first network node; means for receiving from the first network node an indication that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and means for communicating with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node.

[0011] A non-transitory computer-readable medium storing code for wireless communication at an IAB node is described. The non-transitory computer-readable medium may have code for wireless communication stored thereon, which, when executed by the IAB node, causes the IAB node to: establish a radio resource control connection with a first central unit of a first network node; receive an indication from the first network node that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and communicate with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node.

[0012] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: establishing the IAB node-to-central unit connection with the second central unit of the second network node via the radio resource control connection between the IAB node and the first network node; and after the IAB node-to-central unit connection can be established, performing a handover procedure from the first network node to the second network node.

[0013] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: performing a handover procedure from the second network node to the first network node; and after the handover procedure, establishing the IAB node-to-central unit connection with the second central unit of the second network node via the radio resource control connection between the IAB node and the first network node.

[0014] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the indication may include operations, features, components, or instructions for performing the following items: before the radio resource control connection with the first central unit of the first network node can be established, receiving a handover command indicating that the IAB node can establish the radio resource control connection with the first central unit of the first network node, wherein the first network node can be a target node for the handover and the second network node can be a source node for the handover, and wherein the handover command can be the indication.

[0015] In some examples of the methods, apparatus and non-transitory computer-readable media described herein, receiving the indication may include operations, features, components or instructions for performing the following items: receiving a configuration message instructing the IAB node to communicate traffic via the IAB node-to-central unit connection with the second central unit of the second network node using the radio resource control connection between the IAB node and the first network node, wherein the configuration message may be the indication.

[0016] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the configuration message includes an Internet Protocol address configuration; and the IAB node selects an Internet Protocol address based on the Internet Protocol address configuration, and communicates using the Internet Protocol address via the IAB node-to-central unit connection with the second central unit of the second network node.

[0017] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, communicating via the IAB node to central unit connection may include operations, features, components, or instructions for performing the following items: communicating traffic via the IAB node to central unit connection, wherein the traffic may be included in a non-access stratum container corresponding to the radio resource control connection.

[0018] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, communicating via the IAB node to the central unit connection may include operations, features, components, or instructions for performing the following items: communicating traffic via the IAB node to the central unit connection, wherein the traffic includes F1-application protocol messages, flow control transmission protocol messages, or Internet Protocol packets.

[0019] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, communicating via the IAB node to central unit connection may include operations, features, components, or instructions for performing the following items: communicating the service to establish or re-establish the IAB node to central unit connection with the second central unit of the second network node.

[0020] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, communicating via the IAB node to central unit connection may include operations, features, components, or instructions for performing the following items: using the radio resource control connection to send an F1-C protocol data unit for the second network node to the first network node, wherein the F1-C protocol data unit may be encapsulated in a protocol data unit corresponding to the radio resource control connection.

[0021] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, communicating via the IAB node to central unit connection may include operations, features, components, or instructions for performing the following: receiving an F1-C protocol data unit from the second network node from the first network node using the radio resource control connection; and decapsulating the F1-C protocol data unit from the protocol data unit corresponding to the radio resource control connection.

[0022] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the communicating via the IAB node to the central unit connection using the radio resource control connection includes an identifier associated with the second network node.

[0023] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node may be a first base station or a first IAB donor node, or the second network node may be a second base station or a second IAB donor node.

[0024] A method for wireless communication at a first network node is described. The method may include: establishing a radio resource control connection with an IAB node, wherein the radio resource control connection is between a first central unit of the first network node and the IAB node; sending an indication to the IAB node that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and relaying traffic via the IAB node-to-central unit connection between the second network node and the IAB node using the radio resource control connection between the IAB node and the first network node.

[0025] A first network node for wireless communication (e.g., an apparatus for wireless communication at a first network node) is described. The first network node may include a memory and at least one processor, the at least one processor being coupled to the memory. The at least one processor may be configured to: establish a radio resource control connection with an IAB node, wherein the radio resource control connection is between a first central unit of the first network node and the IAB node; send an indication to the IAB node that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and relay traffic via the IAB node-to-central unit connection between the second network node and the IAB node using the radio resource control connection between the IAB node and the first network node.

[0026] Another apparatus for wireless communication at a first network node is described. The apparatus may include: means for establishing a radio resource control connection with an IAB node, wherein the radio resource control connection is between a first central unit of the first network node and the IAB node; means for sending an indication to the IAB node that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and means for relaying traffic via the IAB node-to-central unit connection between the second network node and the IAB node using the radio resource control connection between the IAB node and the first network node.

[0027] A non-transitory computer-readable medium storing code for wireless communication at a first network node is described. The non-transitory computer-readable medium may have code for wireless communication stored thereon, which, when executed by the first network node, causes the first network node to: establish a radio resource control connection with an IAB node, wherein the radio resource control connection is between a first central unit of the first network node and the IAB node; send an indication to the IAB node that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and relay traffic via the IAB node-to-central unit connection between the second network node and the IAB node using the radio resource control connection between the IAB node and the first network node.

[0028] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: after the IAB node to central unit connection can be established, performing a handover procedure to handover the IAB node from the first network node to the second network node, wherein the first network node can be a source node for the handover and the second network node can be a target node for the handover procedure.

[0029] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: before the IAB node to central unit connection can be established, performing a handover procedure to handover the IAB node from the second network node to the first network node, wherein the first network node can be a target node for the handover and the second network node can be a source node for the handover procedure.

[0030] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: preparing to hand over the IAB node from the second network node to the first network node, or preparing to hand over the IAB node from the first network node to the second network node.

[0031] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: determining a first identifier of the second network node and a second identifier of a core network node associated with the IAB node based on handover preparation, wherein the service can be relayed through the IAB node to the central unit connection via the core network node based on the first identifier or the second identifier.

[0032] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, to prepare for the handover, the first node may be configured to prepare for the handover via a base station interface or a core network node interface.

[0033] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the indication may include operations, features, components, or instructions for performing the following items: sending a handover command instructing the IAB node to establish the radio resource control connection with the first central unit of the first network node, wherein the first network node may be a target node for the handover and the second network node may be a source node for the handover, and wherein the handover command may be the indication.

[0034] In some examples of the methods, apparatus and non-transitory computer-readable media described herein, sending the indication may include operations, features, components or instructions for performing the following items: sending a configuration message instructing the IAB node to communicate traffic via the IAB node-to-central unit connection with the second central unit of the second network node using the radio resource control connection between the IAB node and the first network node, wherein the configuration message may be the indication.

[0035] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the configuration message includes an Internet Protocol address configuration for selecting an Internet Protocol address for communicating via the IAB node-to-central unit connection with the second central unit of the second network node.

[0036] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: receiving a request from the second network node, the IAB node, or the core network node to relay the service via the IAB node to the central unit connection; and sending a positive confirmation in response to the request, wherein the first network node relays the service based on sending the positive confirmation.

[0037] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: sending a message to the second network node or the core network node through which the service may be relayed indicating that the service may be interrupted.

[0038] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the message includes an indication to release an identifier associated with the IAB node.

[0039] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: receiving a message indicating the ability of the core network node to relay a service via the IAB node to the central unit connection, wherein the service can be relayed via the core network node based on the ability of the core network node.

[0040] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: communicating with the second network node an Internet Protocol address configuration for the IAB node to connect to the central unit, or communicating a request for the Internet Protocol address configuration for the IAB node to connect to the central unit.

[0041] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, means, or instructions for performing the following: configuring an Internet Protocol address for the IAB node for the IAB node-to-central unit connection with the second central unit of the second network node.

[0042] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the service includes a first identifier of the second network node, a second identifier of a core network node associated with the IAB node, or a third identifier of the IAB node.

[0043] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the traffic may be relayed using a user equipment (UE) associated message or a non-UE associated message, and the UE associated message may be associated with the IAB node.

[0044] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the traffic may be relayed via a base station interface or a core network node interface with the second network node.

[0045] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the traffic may be included in a non-access stratum container corresponding to the radio resource control connection.

[0046] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the traffic includes an F1-application protocol message, a flow control transmission protocol message, or an Internet protocol packet.

[0047] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the traffic may be related to establishing or re-establishing the IAB node-to-central unit connection with the second central unit of the second network node.

[0048] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node may be a first base station or a first IAB donor node, or the second network node may be a second base station or a second IAB donor node.

[0049] A method for wireless communication at a first network node is described. The method may include: receiving an indication of a handover of an IAB node between a second network node and the first network node; determining, based on the indication, an address for forwarding traffic from the first network node to the IAB node via the second network node using an IAB node-to-central unit connection between a first central unit of the first network node and the IAB node, wherein the address is different from an IAB node address indicating the IAB node; and sending the traffic to the address determined by the first network node.

[0050] A first network node for wireless communication (e.g., an apparatus for wireless communication at a first network node) is described. The first network node may include a memory and at least one processor, the at least one processor being coupled to the memory. The at least one processor may be configured to: receive an indication of a handover of an IAB node between a second network node and the first network node; determine, based on the indication, an address for forwarding traffic from the first network node to the IAB node via the second network node using an IAB node-to-central unit connection between a first central unit of the first network node and the IAB node, wherein the address is different from an IAB node address indicating the IAB node; and send the traffic to the address determined by the first network node.

[0051] Another apparatus for wireless communication at a first network node is described. The apparatus may include: means for receiving an indication of a handover of an IAB node between a second network node and the first network node; means for determining, based on the indication, an address for forwarding traffic from the first network node to the IAB node via the second network node using an IAB node-to-central unit connection between a first central unit of the first network node and the IAB node, wherein the address is different from an IAB node address indicating the IAB node; and means for sending the traffic to the address determined by the first network node.

[0052] A non-transitory computer-readable medium storing code for wireless communication at a first network node is described. The non-transitory computer-readable medium may have code for wireless communication stored thereon, which, when executed by the first network node, causes the first network node to: receive an indication of a handover of an IAB node between a second network node and the first network node; determine, based on the indication, an address for forwarding traffic from the first network node to the IAB node via the second network node using an IAB node-to-central unit connection between a first central unit of the first network node and the IAB node, wherein the address is different from an IAB node address indicating the IAB node; and send the traffic to the address determined by the first network node.

[0053] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: before the IAB node to central unit connection can be established, performing a handover procedure to hand over the IAB node from the first network node to the second network node, wherein the first network node can be a source node for the handover and the second network node can be a target node for the handover procedure.

[0054] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: after the IAB node to central unit connection can be established, performing a handover procedure to handover the IAB node from the second network node to the first network node, wherein the first network node can be a target node for the handover and the second network node can be a source node for the handover procedure.

[0055] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: preparing to hand over the IAB node from the second network node to the first network node, or preparing to hand over the IAB node from the first network node to the second network node.

[0056] Some examples of the methods, devices, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: determining a first identifier of the first network node and a second identifier of a core network node associated with the IAB node based on handover preparation, wherein the service can be sent via the core network node based on the first identifier or the second identifier.

[0057] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node prepares for handover via a base station interface with the second network node, and the first network node determines to send the service via the second network node based on an address of the second network node.

[0058] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node prepares for handover via a core network node interface, and the first network node determines to send the traffic via the core network node based on an address of the core network node.

[0059] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: sending a request to the second network node or the core network node for the second network node to relay the service via the IAB node to the central unit connection; and receiving a positive confirmation in response to the request, wherein the service is sent based on the positive confirmation, and the first network node receives the service based on the positive confirmation.

[0060] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: sending a message to the second network node or the core management network node via which the service may be sent indicating that the service may be interrupted.

[0061] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the message includes an indication to release an identifier associated with the IAB node.

[0062] Some examples of the methods, devices, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: receiving a message indicating the ability of the core network node to relay the service via the IAB node to the central unit connection, wherein the service can be sent via the core network node based on the ability of the core network node.

[0063] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: communicating with the second network node an Internet Protocol address configuration for the IAB node to connect to the central unit, or communicating a request for the Internet Protocol address configuration for the IAB node to connect to the central unit.

[0064] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: configuring an Internet Protocol address for the IAB node for the IAB node-to-central unit connection between the first central unit of the first network node and the IAB node.

[0065] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, means, or instructions for performing the following: receiving a protocol data unit for the service from the address.

[0066] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the service includes a first identifier of the first network node, a second identifier of a core network node associated with the IAB node, or a third identifier of the IAB node.

[0067] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the traffic may be sent using a UE-associated message or a non-UE-associated message, and the UE-associated message may be associated with the IAB node.

[0068] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the traffic includes an F1-application protocol message, a flow control transmission protocol message, or an Internet protocol packet.

[0069] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the traffic may be sent to establish or re-establish the IAB node-to-central unit connection with the first central unit of the first network node.

[0070] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node may be a first base station or a first IAB donor node, or the second network node may be a second base station or a second IAB donor node.

[0071] A method for wireless communication at a core network node is described. The method may include: receiving control information from a first network node, the control information indicating that the core network node is to forward one or more containers of an IAB node to a central unit connection of an IAB node, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; sending the one or more containers to the second network node based on the second identifier being included in the control information; caching the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node is to forward the one or more containers; and sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0072] A core network node for wireless communication (e.g., an apparatus for wireless communication at a core network node) is described. The core network node may include a memory and at least one processor coupled to the memory. The at least one processor may be configured to: receive control information from a first network node, the control information indicating that the core network node will forward one or more containers of an IAB node to a central unit connection of an IAB node, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; send the one or more containers to the second network node based on the second identifier being included in the control information; cache the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward the one or more containers; and send one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0073] Another apparatus for wireless communication at a core network node is described. The apparatus may include: a component for receiving control information from a first network node, the control information indicating that the core network node is to forward one or more containers of an IAB node to a central unit connection of an IAB node, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; a component for sending the one or more containers to the second network node based on the second identifier being included in the control information; a component for caching the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node is to forward the one or more containers; and a component for sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0074] A non-transitory computer-readable medium storing code for wireless communication at a core network node is described. The non-transitory computer-readable medium may have code for wireless communication stored thereon, which, when executed by the core network node, causes the core network node to: receive control information from a first network node, the control information indicating that the core network node will forward one or more containers of an IAB node to a central unit connection of an IAB node, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; send the one or more containers to the second network node based on the second identifier being included in the control information; cache the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward the one or more containers; and send one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0075] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the control information may include operations, features, means, or instructions for performing: receiving a request to forward the one or more containers to or from the second network node based on the second identifier being included in the control information.

[0076] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, means, or instructions for performing the following: sending a confirmation message in response to the request.

[0077] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the one or more containers or the one or more other containers may include operations, features, components, or instructions for performing the following items: sending the one or more containers or the one or more other containers based on the confirmation message.

[0078] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: sending a message indicating the ability of the core network node to relay traffic to the first network node or the second network node via the IAB node to central unit connection, wherein the communication of the control information, the one or more containers, or the one or more other containers may be based on the ability of the core network node.

[0079] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: receiving a message indicating the capability of the second network node to relay traffic via the IAB node to the central unit connection, wherein the control information, the one or more containers, or the one or more other containers may be relayed to the second network node based on the capability of the second network node.

[0080] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: receiving a release message from the first network node or the second network node, the release message instructing the core network node to release the cached information, wherein the release message includes an identifier associated with the one or more containers or the first identifier.

[0081] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, means, or instructions for performing: relaying the release message to the first network node or the second network node.

[0082] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node may be a source node of a handover procedure in which the IAB node may be handed over from the first network node to the second network node.

[0083] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the second network node may be a source node of a handover procedure in which the IAB node may be handed over from the second network node to the first network node.

[0084] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the control information, the one or more containers, or the one or more other containers may be included in a non-access stratum message.

[0085] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node corresponds to a network node type, or the second network node corresponds to the network node type, which may be an IAB node type.

[0086] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first identifier associated with the IAB node may be indicated by the first network node or the second network node.

[0087] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the control information includes a handover requirement indicator, a request to create a UE context, a handover request confirmation indicator, a response to an indication to create a UE context, a notification of a handover procedure, a notification of receiving a notification of a handover procedure, a confirmation associated with a notification of a handover procedure, or an indication of completion of release of the UE context.

[0088] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the core network node may be an access and mobility management function or a mobility management entity.

[0089] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node may be a first base station or a first IAB donor node, or the second network node may be a second base station or a second IAB donor node.

[0090] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node or the second network node may be a second core network node.

[0091] A method for wireless communication performed by a first network node is described. The method may include: participating in establishing a communication path between an IAB node and a central unit of a second network node via a core network node, wherein the communication path is an IAB node to central unit connection; and forwarding traffic between the IAB node and the central unit via the core network node using the IAB node to central unit connection.

[0092] A first network node for wireless communication (e.g., an apparatus for wireless communication performed by the first network node) is described. The first network node may include a memory and at least one processor, the at least one processor coupled to the memory. The first network node may be configured to: participate in establishing a communication path between an IAB node and a central unit of a second network node via a core network node, wherein the communication path is an IAB node to central unit connection; and forward traffic between the IAB node and the central unit via the core network node using the IAB node to central unit connection.

[0093] Another apparatus for wireless communication performed by a first network node is described. The apparatus may include: means for participating in establishing a communication path between an IAB node and a central unit of a second network node via a core network node, wherein the communication path is an IAB node to central unit connection; and means for forwarding traffic between the IAB node and the central unit via the core network node using the IAB node to central unit connection.

[0094] A non-transitory computer-readable medium storing code for wireless communication performed by a first network node is described. The code may include instructions executable by a processor to perform the following operations: participate in establishing a communication path between an IAB node and a central unit of a second network node via a core network node, wherein the communication path is an IAB node to central unit connection; and forward traffic between the IAB node and the central unit via the core network node using the IAB node to central unit connection.

[0095] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, participating in establishing the communication path may include operations, features, components, or instructions for performing the following items: establishing a radio resource control connection with the IAB node, wherein the radio resource control connection may be located between a first central unit of the first network node and the IAB node; and sending first control information to the IAB node, the first control information indicating that the IAB node may establish the IAB node-to-central unit connection with the second central unit of the second network node via the radio resource control connection between the IAB node and the first network node, wherein the first control information may be associated with a handover of the IAB node between the first network node and the second network node.

[0096] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: after the IAB node to central unit connection can be established, performing a first handover procedure to hand over the IAB node from the first network node to the second network node; or before the IAB node to central unit connection can be established, performing a second handover procedure to hand over the IAB node from the second network node to the first network node.

[0097] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: preparing to hand over the IAB node from the second network node to the first network node, or preparing to hand over the IAB node from the first network node to the second network node; determining a first identifier of the second network node and a second identifier of the core network node based on the handover preparation; and forwarding the service through the IAB node to the central unit connection via the core network node based on the first identifier or the second identifier.

[0098] In some examples of the methods, apparatus and non-transitory computer-readable media described herein, sending the first control information may include operations, features, components or instructions for performing the following items: sending a configuration message instructing the IAB node to communicate traffic via the IAB node-to-central unit connection with the second central unit of the second network node using the radio resource control connection between the IAB node and the first network node, wherein the configuration message may be the first control information and include an Internet Protocol address configuration, the Internet Protocol address configuration being used to select an Internet Protocol address for communicating via the IAB node-to-central unit connection with the second central unit of the second network node; and configuring the Internet Protocol address for the IAB node for use with the IAB node-to-central unit connection with the second central unit of the second network node.

[0099] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: receiving a request from the second network node, the IAB node, or the core network node to forward the service via the IAB node to the central unit connection; and sending a positive confirmation in response to the request, wherein forwarding the service may be based on sending the positive confirmation.

[0100] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: sending a message indicating that the service may be interrupted to the second network node or the core network node through which the service may be forwarded, the message including an indication to release the identifier associated with the IAB node.

[0101] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, an Internet Protocol address configuration for the IAB node to connect to a central unit, or a request for the Internet Protocol address configuration for the IAB node to connect to a central unit, is communicated with the second network node.

[0102] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, participating in establishing the communication path may include operations, features, components, or instructions for performing the following: receiving an indication of a handover of the IAB node between the first network node and a third network node; and determining, based on the indication, an address for forwarding the service from the first network node to the IAB node via the third network node using the IAB node to connect to the central unit, wherein the address may be different from an IAB node address indicating the IAB node.

[0103] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: before the IAB node to central unit connection can be established, performing a first handover procedure to hand over the IAB node from the first network node to the third network node; or after the IAB node to central unit connection can be established, performing a second handover procedure to hand over the IAB node from the third network node to the first network node.

[0104] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: preparing to hand over the IAB node from the third network node to the first network node, or preparing to hand over the IAB node from the first network node to the third network node; determining a first identifier of the first network node and a second identifier of the core network node based on the handover preparation; and forwarding the service via the core network node based on the first identifier or the second identifier.

[0105] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, preparing for handover may include operations, features, components, or instructions for performing the following items: preparing for handover via a network node interface with the third network node; and determining to forward the service via the third network node based on the second address of the third network node.

[0106] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, preparing for handover may include operations, features, components, or instructions for performing the following: preparing for handover via a core network node interface; and determining to forward the service via the core network node based on a second address of the core network node.

[0107] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: sending a request to the third network node or the core network node for the third network node to forward the service via the IAB node to the central unit connection; receiving a positive confirmation in response to the request; forwarding the service based on the positive confirmation; and receiving the service based on the positive confirmation.

[0108] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following items: sending a message indicating that the service may be interrupted to the third network node or the core network node through which the service may be forwarded, the message including a second indication to release the identifier associated with the IAB node.

[0109] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, an Internet Protocol address configuration for the IAB node to connect to a central unit is communicated with the third network node, or a request for the Internet Protocol address configuration for the IAB node to connect to a central unit is communicated; and an Internet Protocol address is configured for the IAB node for use in the IAB node to connect to a central unit.

[0110] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, means, or instructions for performing the following: receiving a protocol data unit for the service from the address.

[0111] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: receiving a message indicating the ability of the core network node to relay a service via the IAB node to the central unit connection; and relaying the service via the core network node based on the ability of the core network node.

[0112] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the service includes a first identifier of the first network node, a second identifier of the second network node, a third identifier of the core network node associated with the IAB node, or a fourth identifier of the IAB node.

[0113] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, forwarding the service may include operations, features, components, or instructions for performing the following items: forwarding the service using a user equipment (UE) associated message or a non-UE associated message, wherein the UE associated message may be associated with the IAB node.

[0114] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the service includes an F1 application protocol message, and the methods, apparatus, and non-transitory computer-readable media may include additional operations, features, components, or instructions for performing the following items: establishing or re-establishing the IAB node-to-central unit connection with the second central unit of the second network node.

[0115] A method for wireless communication performed by a core network node is described. The method may include: receiving control information from a first network node, the control information indicating that the core network node will forward one or more containers of an IAB node to a central unit connection of an IAB node, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; sending the one or more containers to the second network node based on the second identifier being included in the control information; caching the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward the one or more containers; and sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0116] A core network node for wireless communication (e.g., an apparatus for wireless communication performed by a core network node) is described. The core network node may include a memory and at least one processor coupled to the memory. The core network node may be configured to: receive control information from a first network node, the control information indicating that the core network node will forward one or more containers of an IAB node to a central unit connection of an IAB node, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; send the one or more containers to the second network node based on the second identifier being included in the control information; cache the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward the one or more containers; and send one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0117] Another apparatus for wireless communication performed by a core network node is described. The apparatus may include: a component for receiving control information from a first network node, the control information indicating that the core network node is to forward one or more containers of an IAB node to a central unit connection of an IAB node, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; a component for sending the one or more containers to the second network node based on the second identifier being included in the control information; a component for caching the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node is to forward the one or more containers; and a component for sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0118] A non-transitory computer-readable medium storing code for wireless communication performed by a core network node is described. The code may include instructions that can be executed by a processor to perform the following operations: receiving control information from a first network node, the control information indicating that the core network node will forward one or more containers of an IAB node to a central unit connection of an IAB node, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; sending the one or more containers to the second network node based on the second identifier being included in the control information; caching the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward the one or more containers; and sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0119] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the control information may include operations, features, means, or instructions for performing: receiving a request to forward the one or more containers to or from the second network node based on the second identifier being included in the control information.

[0120] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: sending a message indicating the ability of the core network node to relay traffic to the first network node or the second network node via the IAB node to central unit connection, wherein the communication of the control information, the one or more containers, or the one or more other containers may be based on the ability of the core network node.

[0121] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: receiving a message indicating the ability of the second network node to relay traffic via the IAB node to the central unit connection; and relaying the control information, the one or more containers, or the one or more other containers to the second network node based on the ability of the second network node.

[0122] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for performing the following: receiving a release message from the first network node or the second network node, the release message instructing the core network node to release the cached information, wherein the release message includes an identifier associated with the one or more containers or the first identifier; and relaying the release message to the first network node or the second network node.

[0123] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the first network node may be a source node of a first handover procedure in which the IAB node may be handed over from the first network node to the second network node, or the second network node may be the source node of a second handover procedure in which the IAB node may be handed over from the second network node to the first network node.

[0124] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the control information, the one or more containers, or the one or more other containers may be included in a non-access stratum message.

[0125] A method for wireless communication performed by an IAB node is described. The method may include: establishing a radio resource control connection with a first central unit of a first network node; receiving an indication from the first network node that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and communicating with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node.

[0126] An IAB node for wireless communication (e.g., an apparatus for wireless communication performed by an IAB node) is described. The IAB node may include a memory and at least one processor, the at least one processor being coupled to the memory. The IAB node may be configured to: establish a radio resource control connection with a first central unit of a first network node; receive an indication from the first network node that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and communicate with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node.

[0127] Another apparatus for wireless communication performed by an IAB node is described. The apparatus may include: means for establishing a radio resource control connection with a first central unit of a first network node; means for receiving an indication from the first network node that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and means for communicating with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node.

[0128] A non-transitory computer-readable medium storing code for wireless communication performed by an IAB node is described. The code may include instructions executable by a processor to perform the following operations: establish a radio resource control connection with a first central unit of a first network node; receive an indication from the first network node that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and communicate with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node. BRIEF DESCRIPTION OF THE DRAWINGS

[0129] Figure 1 An example of a wireless communication system supporting an F1 connection option in an integrated access and backhaul (IAB) handover scenario according to one or more aspects of the present disclosure is illustrated.

[0130] Figure 2 An example of a network architecture supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is illustrated.

[0131] Figures 3 to 6 An example of a wireless communication system supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is illustrated.

[0132] Figure 7 and Figure 8 An example of a process flow for supporting the F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is illustrated.

[0133] Fig. 9 and Fig.10 A block diagram of a device supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is shown.

[0134] Fig.11 A block diagram of a communication manager supporting an F1 connection option in an IAB handover scenario is shown in accordance with one or more aspects of the present disclosure.

[0135] Fig.12 A diagram of a system of devices supporting an F1 connection option in an IAB handover scenario is shown in accordance with one or more aspects of the present disclosure.

[0136] Figures 13 to 17 A flow chart illustrating a method for supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is shown. DETAILED DESCRIPTION

[0137] An integrated access and backhaul (IAB) node may be a node that acts as a wireless extension of a backhaul network. In other words, an IAB node may be considered as a base station that is wirelessly connected to other base stations (referred to as donor base stations) and / or other IAB nodes. Similar to other base stations, an IAB node may include a core unit (CU) (or central unit) and one or more distributed units (DU or IAB-DU). The CU of an IAB node may also be referred to as an IAB-MT or a mobile terminal. For example, an IAB node may include an IAB-MT that may support user equipment (UE) functionality, via which the IAB node is scheduled by a "parent" node (e.g., a donor base station, a donor IAB node). Additionally, an IAB node may include one or more IAB DUs, via which the IAB node schedules one or more "child" nodes (such as UE, other IAB nodes, etc.). An IAB donor node may include a donor CU and one or more donor DUs. A user equipment (UE) may communicate with a donor base station via an IAB node. In some wireless communication systems, an IAB node may be mobile. Thus, the IAB node may participate in a handover procedure with different donor base stations.To perform the handover procedure, the IAB node may handover from a first donor base station (eg, a source base station) to a second donor base station (eg, a target base station).

[0138] The handover procedure may include a handover of the IAB-MT to the second base station. However, the IAB-DU may be part of a logical path between the UE and the IAB-MT, where the IAB-DU may be responsible for the connection with the base station via the F1 interface (e.g., an IAB node to CU connection). Therefore, upon completion of the IAB-MT handover procedure, the IAB node may establish a new F1 connection with the second base station. The F1 connection with the second base station is logically made via a different IAB-DU of the IAB node. Therefore, a new logical IAB-DU (e.g., IAB-DUb, relative to the IAB-DUa supporting the initial F1 connection with the first base station) may be established to support the new F1 connection with the second base station. Upon completion of the IAB-MT handover procedure and establishment of the IAB-DUb, the UE may perform a handover procedure from the IAB-DUa to the IAB-DUb. However, before the UE accesses a serving network node (e.g., serving base station, serving IAB donor) via a second (new) F1 interface or accesses a cell associated with the F1 interface via a handover to IAB-DUb, the F1 connection between the first IAB-DU (IAB-DUa) and the first base station needs to be maintained, even after the IAB-MT has dropped its connection with the first base station in favor of a connection with the second base station.

[0139] However, when the IAB-MT is handed over to the second base station, a situation may occur where the F1 connection between the IAB-DUa and the first base station is disconnected, and thus the UE will not be able to access any serving network node via any F1 interface for a period of time. In the case where the first F1 connection is not maintained for a period of time as part of the handover or at the end of the handover, the UE may experience a radio link failure.

[0140] In order to maintain the connection between the UE and the serving network node (via the F1 interface) during the IAB-MT handover procedure, one or more logical channels (e.g., a radio resource control (RRC) channel, a non-access stratum (NAS) channel) may be utilized to forward the F1 container between the UE and the base station to establish a "detour" F1 path. The detour path may be used because the IAB-MT may have dropped (or will soon drop) the physical connection with the source base station in favor of the connection with the target base station. In some cases, the F1 detour path (e.g., make before break) may be established before the IAB-MT handover procedure. In this case, the F1 detour path may be established between the IAB-DUb and the target base station (e.g., the first base station) via a logical channel associated with the source base station (e.g., the second base station), so that the source base station forwards the F1 container from the IAB-DUb to the target base station, or vice versa. In some cases, the F1 detour path (e.g., make before make) may be established after the IAB-MT handover procedure but before the UE handover procedure. In this case, an F1 detour path may be established between the IAB-DUa and the source base station (e.g., the first base station) via a logical channel associated with the target base station (e.g., the second base station), such that the target base station forwards the F1 container from the IAB-DUa to the source base station, or vice versa.

[0141] When the F1 interface between the first base station and IAB-DUa is established via a detour and in a make-before-break scenario, the IAB-MT will perform a handover to the second base station, and the UE will then perform a handover to IAB-DUb. In a make-before-break scenario, since the IAB-MT has performed a handover to the second base station, the UE will perform a handover to IAB-DUb. In either scenario, the UE may perform a handover to IAB-DUb, and an F1 connection between the IAB-DU and the second base station will be established to support the UE. Therefore, the F1 connection (e.g., F1 detour) with the first base station may then be released. Therefore, the detour path may be maintained for a period of time until the UE successfully hands over to IAB-DUb to ensure that the UE does not experience a radio link failure during such a handover procedure.

[0142] Certain aspects of the subject matter described herein may be implemented to achieve one or more advantages. The described techniques may support improvements in performing IAB node handover procedures by improving reliability and reducing latency, among other advantages. Thus, the supported techniques may include improved network operation, and in some examples, may improve network efficiency, among other things.

[0143] First, various aspects of the disclosure are described in the context of a wireless communication system. Various aspects of the disclosure are further illustrated by and described with reference to process flows. Various aspects of the disclosure are further illustrated and described by and with reference to apparatus diagrams, system diagrams, and flow diagrams related to the F1 connection option in an IAB handover scenario.

[0144] Figure 1 An example of a wireless communication system 100 supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is illustrated. The wireless communication system 100 may include one or more network entities 105, one or more UEs 115, and a core network 130. In some examples, the wireless communication system 100 may be a long term evolution (LTE) network, an advanced LTE (LTE-A) network, an LTE-A Pro network, a new radio (NR) network, or a network operating according to other systems and radio technologies (including future systems and radio technologies not explicitly mentioned herein).

[0145] The network entities 105 may be dispersed throughout a geographic area to form the wireless communication system 100, and may include devices in different forms or with different capabilities. In various aspects, the network entities 105 may be referred to as network elements, mobility elements, radio access network (RAN) nodes, or network equipment, etc. In some aspects, the network entities 105 and the UE 115 may communicate wirelessly via one or more communication links 125 (e.g., radio frequency (RF) access links). For example, the network entity 105 may support a coverage area 110 (e.g., a geographic coverage area) within which the UE 115 and the network entity 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area within which the network entity 105 and the UE 115 may support signal communications according to one or more radio access technologies (RATs).

[0146] The UEs 115 may be dispersed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 may be stationary or mobile, or both stationary and mobile at different times. The UEs 115 may be devices in different forms or with different capabilities. Figure 1 Some example UEs 115 are illustrated in FIG. 1. The UEs 115 described herein may be capable of supporting communication with various types of devices, such as Figure 1Communicate with other UEs 115 or network entities 105) as shown.

[0147] As described herein, a node (which may be referred to as a node, a network node, a network entity, or a wireless node) may include, may be, or may be included in (e.g., as a component of) a base station (e.g., any base station described herein), a UE (e.g., any UE described herein), a network controller, an apparatus, a device, a computing system, an IAB node, a distributed unit (DU), a central unit (CU), a remote / radio unit (RU) (which may also be referred to as a remote radio unit (RRU)), and / or another processing entity configured to perform any of the techniques described herein. For example, the network node may be a UE. For another example, the network node may be a base station or a network entity. For another example, a first network node may be configured to communicate with a second network node or a third network node. In one aspect of this example, the first network node may be a UE, the second network node may be a base station, and the third network node may be a UE. In another aspect of this example, the first network node may be a UE, the second network node may be a base station, and the third network node may be a base station. In yet other aspects of this example, the first network node, the second network node, and the third network node may be different relative to these examples. Similarly, references to UE, base station, device, equipment, computing system, etc. may include disclosure of UE, base station, device, equipment, computing system, etc. as a network node. For example, a disclosure that a UE is configured to receive information from a base station also discloses that a first network node is configured to receive information from a second network node. Consistent with the present disclosure, once a specific example is expanded according to the present disclosure (e.g., a UE is configured to receive information from a base station also discloses that a first network node is configured to receive information from a second network node), a broader example of a narrower example may be interpreted in reverse, but in a broad, open-ended manner. In the above example where a UE is configured to receive information from a base station also discloses that a first network node is configured to receive information from a second network node, the first network node may refer to a first UE configured to receive information, a first base station, a first device, a first device, a first computing system, a first group of one or more components, a first processing entity, etc.; and the second network node may refer to a second UE, a second base station, a second device, a second device, a second computing system, a second group of one or more components, a second processing entity, etc.

[0148] As described herein, different terms may be used in various aspects to describe the communication of information (e.g., any information, signal, etc.). Disclosure of one communication term includes disclosure of other communication terms. For example, a first network node may be described as being configured to send information to a second network node. In this example and consistent with the present disclosure, disclosure that the first network node is configured to send information to the second network node includes disclosure that the first network node is configured to provide, transmit, output, communicate, or send information to the second network node. Similarly, in this example and consistent with the present disclosure, disclosure that the first network node is configured to send information to the second network node includes disclosure that the second network node is configured to receive, obtain, or decode information provided, transmitted, output, communicated, or sent by the first network node.

[0149] In some examples, the network entities 105 may communicate with the core network 130, or with each other, or both. For example, the network entities 105 may communicate with the core network 130 via one or more backhaul communication links 120 (e.g., according to S1, N2, N3, or other interface protocols). In some examples, the network entities 105 may communicate with each other directly (e.g., directly between each network entity 105) or indirectly (e.g., via the core network 130) via the backhaul communication links 120 (e.g., according to X2, Xn, or other interface protocols). In some examples, the network entities 105 may communicate with each other via midhaul communication links 162 (e.g., according to a midhaul interface protocol) or fronthaul communication links 168 (e.g., according to a fronthaul interface protocol) or any combination thereof. The backhaul communication links 120, midhaul communication links 162, or fronthaul communication links 168 may be or may include one or more wired links (e.g., electrical links, optical fiber links), one or more wireless links (e.g., radio links, wireless optical links), etc. or various combinations thereof. UE 115 may communicate with core network 130 via communication link 155 .

[0150] One or more of the network entities 105 described herein may include or may be referred to as a base station 140 (e.g., a transceiver base station, a radio base station, an NR base station, an access point, a radio transceiver, a Node B, an evolved Node B (eNB), a next-generation Node B, or a Gigabit Node B (any of which may be referred to as a gNB), a 5G NB, a next-generation eNB (ng-eNB), a Home Node B, a Home Evolved Node B, or other suitable terminology). In some aspects, the network entity 105 (e.g., a base station 140) may be implemented in an aggregated (e.g., monolithic, stand-alone) base station architecture that may be configured to utilize a protocol stack that is physically or logically integrated within a single network entity 105 (e.g., a single RAN node, such as a base station 140).

[0151] In some aspects, the network entity 105 may be implemented in a disaggregated architecture (e.g., a disaggregated base station architecture, a disaggregated RAN architecture) that may be configured to utilize a protocol stack that is physically or logically distributed between two or more network entities 105, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance), or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN)). For example, the network entity 105 may include one or more of the following: a central unit (CU) 160, a distributed unit (DU) 165, a radio unit (RU) 170, a RAN intelligent controller (RIC) 175 (e.g., a near real-time RIC (near RT RIC), a non-real-time RIC (non-RT RIC)), a service management and orchestration (SMO) 180 system, or any combination thereof. The RU 170 may also be referred to as a radio head, a smart radio head, a remote radio head (RRH), a remote radio unit (RRU), or a transmit receive point (TRP). One or more components of the network entity 105 in the decomposed RAN architecture may be co-located, or one or more components of the network entity 105 may be located in distributed locations (e.g., separate physical locations). In some aspects, one or more network entities 105 of the decomposed RAN architecture may be implemented as virtual units (e.g., virtual CU (VCU), virtual DU (VDU), virtual RU (VRU)).

[0152] The functional split between CU 160, DU 165, and RU 170 is flexible and may support different functionalities, depending on which functions (e.g., network layer functions, protocol layer functions, baseband functions, RF functions, and any combination thereof) are performed at CU 160, DU 165, and RU 170. For example, a functional split of a protocol stack may be employed between CU 160 and DU 165, such that CU 160 may support one or more layers of a protocol stack and DU 165 may support one or more different layers of a protocol stack. In some aspects, CU 160 may host higher protocol layer (e.g., layer 3 (L3), layer 2 (L2)) functionality and signaling (e.g., radio resource control (RRC), service data adaptation protocol (SDAP), packet data convergence protocol (PDCP)). The CU 160 may be connected to one or more DUs 165 or RUs 170, and the one or more DUs 165 or RUs 170 may host lower protocol layers, such as layer 1 (L1) (e.g., physical (PHY) layer) or L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functionality and signaling, and may each be at least partially controlled by the CU 160. Additionally or alternatively, a functional split of the protocol stack may be employed between the DUs 165 and the RUs 170, such that the DUs 165 may support one or more layers of the protocol stack, and the RUs 170 may support one or more different layers of the protocol stack. The DUs 165 may support one or more different cells (e.g., via one or more RUs 170). In some cases, the functional split between CU 160 and DU 165 or between DU 165 and RU 170 may be within the protocol layer (e.g., some functions of the protocol layer may be performed by one of CU 160, DU 165, or RU 170, while other functions of the protocol layer are performed by a different one of CU 160, DU 165, or RU 170). CU 160 may be further functionally split into CU control plane (CU-CP) functions and CU user plane (CU-UP) functions. CU 160 may be connected to one or more DUs 165 via midhaul communication links 162 (e.g., F1, F1-c, F1-u), and DU 165 may be connected to one or more RUs 170 via fronthaul communication links 168 (e.g., open fronthaul (FH) interface). In some aspects, midhaul communication link 162 or fronthaul communication link 168 may be implemented according to an interface (eg, a channel) between layers of a protocol stack supported by respective network entities 105 communicating via such communication links.

[0153] In some wireless communication systems (e.g., wireless communication system 100), infrastructure and spectrum resources for radio access may support wireless backhaul link capabilities to supplement wired backhaul connections, thereby providing an IAB network architecture (e.g., to core network 130). In some cases, in an IAB network, one or more network entities 105 (e.g., IAB nodes 104) may be partially controlled by each other. One or more IAB nodes 104 may be referred to as donor entities or IAB donors. One or more DUs 165 or one or more RUs 170 may be controlled in part by one or more CUs 160 associated with a donor network entity 105 (e.g., a donor base station 140). One or more donor network entities 105 (e.g., IAB donors) may communicate with one or more additional network entities 105 (e.g., IAB nodes 104) via supported access and backhaul links (e.g., backhaul communication links 120). The IAB node 104 may include an IAB mobile terminal (IAB-MT) controlled (e.g., scheduled) by a coupled IAB donor's DU 165. The IAB-MT may include an independent antenna group for relaying communications with the UE 115, or may share the same antenna of the IAB node 104 (e.g., of the RU 170) for access via the DU 165 of the IAB node 104 (e.g., referred to as a virtual IAB-MT (vIAB-MT)). In some aspects, the IAB node 104 may include a DU 165 that supports a communication link with additional entities (e.g., IAB node 104, UE 115) within a relay chain or configuration of the access network (e.g., downstream). In such cases, one or more components of the decomposed RAN architecture (e.g., one or more IAB nodes 104 or components of the IAB node 104) may be configured to operate according to the techniques described herein.

[0154] For example, an access network (AN) or RAN may include communications between an access node (e.g., an IAB donor), an IAB node 104, and one or more UEs 115. The IAB donor may facilitate a connection between the core network 130 and the AN (e.g., via a wired or wireless connection to the core network 130). That is, the IAB donor may refer to a RAN node having a wired or wireless connection to the core network 130. The IAB donor may include a CU 160 and at least one DU 165 (e.g., and RU 170), in which case the CU 160 may communicate with the core network 130 via an interface (e.g., a backhaul link). The IAB donor and the IAB node 104 may communicate via an F1 interface according to a protocol that defines signaling messages (e.g., an F1 AP protocol). Additionally or alternatively, CU 160 may communicate with the core network via an interface (which may be an example of a portion of a backhaul link) and may communicate with other CUs 160 (such as CU 160 associated with an alternative IAB donor) via an Xn-C interface (which may be an example of a portion of a backhaul link).

[0155] The IAB node 104 may refer to a RAN node that provides IAB functionality (e.g., access, wireless self-backhaul capabilities for UE 115). The DU 165 may act as a distributed scheduling node toward a child node associated with the IAB node 104, and the IAB-MT may act as a scheduled node toward a parent node associated with the IAB node 104. That is, the IAB donor may be referred to as a parent node that communicates with one or more child nodes (e.g., the IAB donor may relay transmissions for the UE through one or more other IAB nodes 104). Additionally or alternatively, the IAB node 104 may also be referred to as a parent node or child node of other IAB nodes 104, depending on the relay chain or configuration of the AN. Therefore, the IAB-MT entity of the IAB node 104 may provide a Uu interface for the child IAB node 104 to receive signaling from the parent IAB node 104, and the DU interface (e.g., DU 165) may provide a Uu interface for the parent IAB node 104 to signal to the child IAB node 104 or the UE 115.

[0156] For example, the IAB node 104 may be referred to as a parent node supporting child IAB node communications, or as a child node associated with an IAB donor, or both. The IAB donor may include a CU 160 having a wired or wireless connection to the core network 130 (e.g., a backhaul communication link 120), and may act as a parent node of the IAB node 104. For example, the DU 165 of the IAB donor may relay transmissions to the UE 115 via the IAB node 104, and may directly signal the transmissions to the UE 115, or both. The CU 160 of the IAB donor may signal the establishment of a communication link to the IAB node 104 via the F1 interface, and the IAB node 104 may schedule transmissions (e.g., transmissions relayed from the IAB donor to the UE 115) via the DU 165. That is, data may be relayed to and from the IAB node 104 via signaling via the NR Uu interface of the MT to the IAB node 104. Communications with the IAB node 104 may be scheduled by the DU 165 of the IAB donor, and communications with the IAB node 104 may be scheduled by the DU 165 of the IAB node 104 .

[0157] In the case where the techniques described herein are applied to the context of a decomposed RAN architecture, one or more components of the decomposed RAN architecture may be configured to support the F1 connection option in the IAB handover scenario as described herein. For example, some operations described as being performed by the UE 115 or the network entity 105 (e.g., the base station 140) may be additionally or alternatively performed by one or more components of the decomposed RAN architecture (e.g., the IAB node 104, the DU 165, the CU 160, the RU 170, the RIC 175, the SMO 180).

[0158] UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable terminology, where a "device" may also be referred to as a unit, a station, a terminal, or a client, etc. UE 115 may also include or may be referred to as a personal electronic device, such as a cellular phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, or a personal computer. In some aspects, UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communication (MTC) device, etc., which may be implemented in, for example, an appliance or a vehicle, a meter, etc.

[0159] The UE 115 described herein may be capable of communicating with various types of devices, such as other UEs 115, which may sometimes act as relays, as well as network entities 105 and network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, relay base stations, etc. Figure 1 as shown in .

[0160] The UE 115 and the network entity 105 may use resources associated with one or more carriers to wirelessly communicate with each other via one or more communication links 125 (e.g., access links). The term "carrier" may refer to a set of RF spectrum resources having a physical layer structure defined to support the communication link 125. For example, a carrier for the communication link 125 may include a portion of an RF spectrum band (e.g., a bandwidth portion (BWP)) that operates according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling for coordinating carrier operations, user data, or other signaling. The wireless communication system 100 may support communications with the UE 115 using carrier aggregation or multi-carrier operation. Depending on the carrier aggregation configuration, the UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers. Carrier aggregation may be used with both frequency division duplex (FDD) and time division duplex (TDD) component carriers. Communication between the network entity 105 and other devices may refer to communication between these devices and any part (e.g., entity, sub-entity) of the network entity 105. For example, the terms "send", "receive", or "communicate" when referring to the network entity 105 may refer to any part of the network entity 105 (e.g., base station 140, CU 160, DU 165, RU 170) of the RAN communicating with another device (e.g., directly or via one or more other network entities 105).

[0161] The signal waveform transmitted via the carrier may be composed of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques, such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)). In a system using MCM techniques, a resource element may refer to a resource of one symbol period (e.g., the duration of one modulation symbol) and one subcarrier, in which case the symbol period and the subcarrier spacing may be inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both), so that (e.g., in the transmission duration) a relatively high number of resource elements and a relatively high order modulation scheme may correspond to a relatively high communication rate. Wireless communication resources may refer to a combination of RF spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial resources may increase the data rate or data integrity used for communication with UE 115.

[0162] The time interval for the network entity 105 or the UE 115 may be expressed as a multiple of a basic time unit, which may be, for example, a sampling period Ts =1 / (Δf max ·N f ) seconds, where Δf max It can represent the supported subcarrier spacing, and N f The supported discrete Fourier transform (DFT) size may be indicated. The time intervals of the communication resources may be organized according to radio frames, each having a specific duration (e.g., 10 milliseconds (ms)). Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023).

[0163] Each frame may include multiple consecutively numbered subframes or time slots, and each subframe or time slot may have the same duration. In some aspects, a frame may be divided into subframes (e.g., in the time domain), and each subframe may be further divided into a certain number of time slots. Alternatively, each frame may include a variable number of time slots, and the number of time slots may depend on the subcarrier spacing. Each time slot may include a certain number of symbol periods (e.g., depending on the length of the cyclic prefix appended in front of each symbol period). In some wireless communication systems 100, the time slot may be further divided into a plurality of mini-time slots associated with one or more symbols. Excluding the cyclic prefix, each symbol period may be associated with one or more (e.g., N f The duration of a symbol period may depend on the subcarrier spacing or the operating frequency band.

[0164] A subframe, slot, mini-slot, or symbol may be the smallest scheduling unit of the wireless communication system 100 (e.g., in the time domain) and may be referred to as a transmit time interval (TTI). In some aspects, the TTI duration (e.g., a certain number of symbol periods in a TTI) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communication system 100 may be dynamically selected (e.g., in a burst of a shortened TTI (sTTI)).

[0165] Physical channels may be multiplexed using carriers for communication according to various techniques. For example, physical control channels and physical data channels may be multiplexed via downlink carriers using one or more of a time division multiplexing (TDM) technique, a frequency division multiplexing (FDM) technique, or a hybrid TDM-FDM technique for signaling communication. A control region (e.g., a control resource set (CORESET)) for a physical control channel may be defined by a set of symbol periods and may extend across a system bandwidth or a subgroup of a system bandwidth of a carrier. One or more control regions (e.g., CORESETs) may be configured for a group of UEs 115. For example, one or more of the UEs 115 may monitor or search the control region for control information according to one or more search space sets, and each search space set may include one or more control channel candidates in one or more aggregation levels arranged in a cascaded manner. The aggregation level of the control channel candidate may refer to the amount of control channel resources (e.g., control channel elements (CCEs)) associated with the coded information for a control information format having a given payload size. The search space sets may include a common search space set configured for transmitting control information to multiple UEs 115 , and a UE-specific search space set for transmitting control information to a specific UE 115 .

[0166] In some aspects, the network entities 105 (e.g., base stations 140, RUs 170) may be mobile and, therefore, provide communication coverage for mobile coverage areas 110. In some aspects, different coverage areas 110 associated with different technologies may overlap, but the different coverage areas 110 may be supported by the same network entity 105. In some other aspects, overlapping coverage areas 110 associated with different technologies may be supported by different network entities 105. The wireless communication system 100 may include, for example, a heterogeneous network in which different types of network entities 105 provide coverage for various coverage areas 110 using the same or different radio access technologies.

[0167] The wireless communication system 100 may be configured to support ultra-reliable communication or low-latency communication or various combinations thereof. For example, the wireless communication system 100 may be configured to support ultra-reliable low-latency communication (URLLC). The UE 115 may be designed to support ultra-reliable, low-latency or critical functions. Ultra-reliable communication may include private communication or group communication, and may be supported by one or more services (such as push-to-talk, video or data). Support for ultra-reliable, low-latency functions may include prioritization of services, and such services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency and ultra-reliable low-latency may be used interchangeably herein.

[0168] In some aspects, a UE 115 may be configured to support communication directly with other UEs 115 via a device-to-device (D2D) communication link 135 (e.g., according to a peer-to-peer (P2P), D2D, or sidelink protocol). In some aspects, one or more UEs 115 in a group that are performing D2D communication may be within a coverage area 110 of a network entity 105 (e.g., a base station 140, a RU 170), which may support aspects of such D2D communication configured (e.g., scheduled) by the network entity 105. In some aspects, one or more UEs 115 in such a group may be outside of the coverage area 110 of the network entity 105, or may otherwise be unable or not configured to receive transmissions from the network entity 105. In some aspects, a group of UEs 115 communicating via D2D communication may support a one-to-many (1:M) system, in which each UE 115 transmits to each of the other UEs 115 in the group. In some aspects, the network entity 105 may facilitate scheduling resources for D2D communications. In some other aspects, D2D communications may be conducted between UEs 115 without involving the network entity 105.

[0169] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or a 5G core (5GC), which may include at least one control plane entity (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) for managing access and mobility and at least one user plane entity (e.g., a serving gateway (S-GW), a packet data network (PDN) gateway (P-GW), or a user plane function (UPF)) for routing packets or interconnecting to an external network. The control plane entity may manage NAS functions such as mobility, authentication, and bearer management of UE 115 served by a network entity 105 (e.g., a base station 140) associated with the core network 130. User IP packets may be delivered via a user plane entity, which may provide IP address allocation and other functions. The user plane entity may be connected to an IP service 150 for one or more network operators. The IP service 150 may include access to the Internet, an intranet, an IP multimedia subsystem (IMS), or a packet-switched streaming service.

[0170] The wireless communication system 100 may operate using one or more frequency bands that may be in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). Generally speaking, the region from 300 MHz to 3 GHz is referred to as the ultra-high frequency (UHF) region or decimeter band because the wavelength range is about one decimeter to one meter. UHF waves may be blocked or redirected by buildings and environmental features (which may be referred to as clusters), but these waves may be sufficient to penetrate structures so that macro cells provide services to UEs 115 located indoors. Communications using UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to communications using lower frequencies and longer waves in the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz.

[0171] The wireless communication system 100 may utilize both licensed RF spectrum bands and unlicensed RF spectrum bands. For example, the wireless communication system 100 may employ license assisted access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology using unlicensed bands (such as the 5 GHz industrial, scientific, and medical (ISM) band). When operating using unlicensed RF spectrum bands, devices such as network entities 105 and UEs 115 may employ carrier sensing for conflict detection and avoidance. In some aspects, operations performed using unlicensed bands may be based on a carrier aggregation configuration combined with component carriers for operations performed using licensed bands (e.g., LAA). Operations performed using unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among others.

[0172] The network entity 105 (e.g., base station 140, RU 170) or UE 115 may be equipped with multiple antennas that can be used to employ technologies such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of the network entity 105 or UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly (such as an antenna tower). In some aspects, the antennas or antenna arrays associated with the network entity 105 may be located in different geographical locations. The network entity 105 may include an antenna array having a set of rows and columns of antenna ports that the network entity 105 can use to support beamforming for communications with the UE 115. Similarly, the UE 115 may include one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support RF beamforming for signals sent via the antenna ports.

[0173] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., network entity 105, UE 115) to form or direct an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining signals communicated via antenna elements of an antenna array so that some signals propagating at a particular orientation relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to signals communicated via antenna elements may include the transmitting device or the receiving device applying an amplitude offset, a phase offset, or both to signals carried via antenna elements associated with the device. Adjustments associated with each of the antenna elements may be defined by a set of beamforming weights associated with a particular orientation (e.g., relative to the antenna array of the transmitting device or the receiving device or relative to some other orientation).

[0174] In some wireless communication systems 100, the IAB node 104 may act as a wireless extension of the backhaul network. Therefore, the IAB node 104 may be considered as a base station that is wirelessly connected to other base stations (referred to as donor base stations). The UE 115 may communicate with the donor base station via the IAB node 104. In some cases, the IAB node 104 may be mobile and may therefore perform a handover procedure from one donor base station to another. The technology for implementing such a handover procedure may be improved.

[0175] In some cases, the IAB node 104 may perform a handover procedure, and partial / full migration between IAB donors may require F1 connectivity between the IAB-DU (e.g., mobile IAB-DU) and the source IAB-donor CU. Partial migration between donors may utilize Xn handover and Xn procedures to migrate services to the target path. However, the Xn interface may not always be available (e.g., between RAN networks of different vendors). For example, when a mobile IAB node roams from an HPLMN to a VPLMN, the Xn interface is typically unavailable. In partial migration between donors, the F1 service between the mobile IAB-DU and the source IAB-donor CU may be routed via the target donor DU. For such roaming scenarios, IP connectivity may be required between the IAB-donor DU of the VPLMN and the IAB-donor CU of the HPLMN (e.g., the backhaul IP network of the PLMN may need to have interconnectivity). However, in some cases, this is not supported.

[0176] In some wireless communication systems (such as the wireless communication system 100), the technology may support an F1 connection (e.g., an IAB node to central unit connection) at the IAB node 104 during the IAB handover procedure to maintain a radio link at the UE 115 during the IAB handover procedure. For example, the technology described herein provides F1 connectivity of the core network between the mobile IAB-DU and the source IAB-donor CU or the target IAB-donor CU. In order to maintain the F1 connection to serve the UE 115 during the IAB handover procedure, one or more logical channels (e.g., RRC channels, NAS channels) may be utilized to forward the F1 container between the UE 115 and the base station 140 to establish a "detour" F1 path. In some cases, the F1 connection may be established with the target base station 140 in a make-before-break manner, or the F1 connection may be established with the source base station in a break-before-make manner. For example, the IAB node 104 may establish an RRC connection with the first central unit 160 of the first network node (e.g., the first base station 140, the first donor base station 140). The IAB node 104 may receive an indication or otherwise determine to establish an F1 connection with the second central unit 160 of the second network node (e.g., the second base station 140, the second donor base station 140) via the RRC connection between the IAB node 104 and the first network node. Subsequently, the IAB node 104 may communicate with the second network node via the F1 connection using the RRC connection between the IAB node 104 and the first network node.

[0177] In some cases, a first network node (e.g., donor base station 140) forwarding an F1 container (e.g., a non-F1 called end base station) may establish an RRC connection with an IAB node 104, wherein the RRC connection may be located between a first central unit 160 of the first network node and the IAB node 104. The first network node may identify and in some cases may send first control information to the IAB node 104, the first control information indicating that the IAB node 104 will establish an F1 connection with a second central unit of a second network node (e.g., F1 called end base station 140) via an RRC connection between the IAB node 104 and the first network node. The first network node may relay traffic via an F1 connection between the second network node and the IAB node 104 using the RRC connection between the IAB node 104 and the first network node.

[0178] In some cases, the second network node (e.g., the donor base station 140, the F1 called end base station 140) may receive an indication of the handover of the IAB node 104 from the first network node to the second network node or otherwise determine that the IAB node is handed over from the first network node to the second network node, or vice versa. The second network node may determine an address based on the indication, which is used to forward the service via the first network node using the F1 connection between the central unit 160 of the second network node and the IAB node 104. The second network node may send the service to the address. In some cases, the first network node may be the source base station, and the second network node may be the target base station (such as in a connect-before-break scenario). In some cases, the first network node may be the target base station, and the second network node may be the source base station (such as in a connect-before-break scenario).

[0179] Figure 2 An example of a network architecture 200 (e.g., a disaggregated base station architecture, a disaggregated RAN architecture) supporting an F1 connectivity option in an IAB handover scenario according to one or more aspects of the present disclosure is illustrated. The network architecture 200 may illustrate an example for implementing one or more aspects of the wireless communication system 100. The network architecture 200 may include one or more CUs 160-a, which may communicate directly with a core network 130-a via a backhaul communication link 120-a, or indirectly with a core network 130-a through one or more disaggregated network entities 105 (e.g., a near RT RIC 175-b via an E2 link, or a non-RT RIC 175-a associated with an SMO 180-a (e.g., an SMO framework), or both. The CU 160-a may communicate with one or more DUs 165-a via corresponding midhaul communication links 162-a (e.g., an F1 interface). The DU 165-a may communicate with one or more RUs 170-a via corresponding fronthaul communication links 168-a. The RU 170-a may be associated with a respective coverage area 110-a and may communicate with the UE 115-a via one or more communication links 125-a. In some implementations, the UE 115-a may be served simultaneously by multiple RUs 170-a.

[0180] Each of the network entities 105 of the network architecture 200 (e.g., CU 160-a, DU 165-a, RU 170-a, non-RT RIC 175-a, near-RT RIC 175-b, SMO 180-a, open cloud (O-Cloud) 205, open eNB (O-eNB) 210) may include one or more interfaces or may be coupled to one or more interfaces configured to receive or send signals (e.g., data, information) via a wired or wireless transmission medium. Each network entity 105 or an associated processor (e.g., a controller) that provides instructions to an interface of the network entity 105 may be configured to communicate with one or more of the other network entities 105 via a transmission medium. For example, the network entity 105 may include a wired interface that is configured to receive signals on a wired transmission medium or to send signals to one or more of the other network entities 105 on a wired transmission medium. Additionally or alternatively, the network entity 105 may include a wireless interface, which may include a receiver, a transmitter, or a transceiver (e.g., an RF transceiver) configured to receive signals on a wireless transmission medium, or to send signals to one or more of the other network entities 105 on a wireless transmission medium, or both.

[0181] In some aspects, CU 160-a may host one or more higher layer control functions. Such control functions may include RRC, PDCP, SDAP, etc. Each control function may be implemented with an interface configured to communicate signals with other control functions hosted by CU 160-a. CU 160-a may be configured to handle user plane functionality (e.g., CU-UP), control plane functionality (e.g., CU-CP), or a combination thereof. In some aspects, CU 160-a may be logically split into one or more CU-UP units and one or more CU-CP units. When implemented in an O-RAN configuration, the CU-UP unit may communicate bidirectionally with the CU-CP unit via an interface (such as an E1 interface). As needed, CU 160-a may be implemented to communicate with DU 165-a for network control and signaling.

[0182] DU 165-a may correspond to a logical unit that includes one or more functions (e.g., base station functions, RAN functions) for controlling the operation of one or more RUs 170-a. In some aspects, DU 165-a may host one or more of the RLC layer, the MAC layer, and one or more aspects of the PHY layer (e.g., high PHY layers, such as modules for FEC encoding and decoding, scrambling, modulation and demodulation, etc.) at least in part based on functional splits (such as those defined by the Third Generation Partnership Project (3GPP)). In some aspects, DU 165-a may also host one or more low PHY layers. Each layer may be implemented using an interface that is configured to communicate signals with other layers hosted by DU 165-a or with control functions hosted by CU 160-a.

[0183] In some aspects, lower layer functionality may be implemented by one or more RUs 170-a. For example, a RU 170-a controlled by a DU 165-a may correspond to a logical node that hosts RF processing functions or low PHY layer functions (e.g., performing fast Fourier transform (FFT), inverse FFT (iFFT), digital beamforming, physical random access channel (PRACH) extraction and filtering, etc.) or both based at least in part on functional splitting (such as lower layer functional splitting). In such an architecture, the RU 170-a may be implemented to handle over-the-air (OTA) communications with one or more UEs 115-a. In some specific implementations, real-time and non-real-time aspects of control plane and user plane communications with the RU 170-a may be controlled by the corresponding DU 165-a. In some aspects, such a configuration may enable the implementation of the DU 165-a and CU 160-a in a cloud-based RAN architecture (such as a vRAN architecture).

[0184] The SMO 180-a may be configured to support RAN deployment and provisioning of non-virtualized and virtualized network entities 105. For non-virtualized network entities 105, the SMO 180-a may be configured to support the deployment of dedicated physical resources for RAN coverage requirements, which may be managed via an operation and maintenance interface (e.g., an O1 interface). For virtualized network entities 105, the SMO 180-a may be configured to interact with a cloud computing platform (e.g., O-Cloud 205) to perform network entity lifecycle management (e.g., instantiating virtualized network entities 105) via a cloud computing platform interface (e.g., an O2 interface). Such virtualized network entities 105 may include, but are not limited to, CU 160-a, DU 165-a, RU 170-a, and near-RT RIC 175-b. In some specific implementations, the SMO 180-a may communicate (e.g., via an O1 interface) with components configured according to a 4G RAN. Additionally or alternatively, in some implementations, the SMO 180-a may communicate directly with one or more RUs 170-a via an O1 interface. The SMO 180-a may also include a non-RT RIC 175-a configured to support the functionality of the SMO 180-a.

[0185] The non-RT RIC 175-a may be configured to include logic functions that enable non-real-time control and optimization of RAN elements and resources, artificial intelligence (AI) or machine learning (ML) workflows including model training and updating, or policy-based guidance of applications / features in the near-RT RIC 175-b. The non-RT RIC 175-a may be coupled to or communicate with the near-RT RIC 175-b (e.g., via an A1 interface). The near-RT RIC 175-b may be configured to include logic functions that enable near-real-time control and optimization of RAN elements and resources via data collection and actions on an interface (e.g., via an E2 interface) that connects one or more CUs 160-a, one or more DUs 165-a, or both, and the O-eNB 210 with the near-RT RIC 175-b.

[0186] In some aspects, in order to generate an AI / ML model to be deployed in the near-RT RIC 175-b, the non-RT RIC 175-a may receive parameters or external enrichment information from an external server. Such information may be utilized by the near-RT RIC 175-b and may be received from a non-network data source or from a network function at the SMO 180-a or the non-RT RIC 175-a. In some aspects, the non-RT RIC 175-a or the near-RT RIC 175-b may be configured to tune RAN behavior or performance. For example, the non-RT RIC 175-a may monitor long-term trends and patterns of performance and employ an AI model or ML model to perform corrective actions through the SMO 180-a (e.g., via reconfiguration of O1) or via the generation of a RAN management policy (e.g., an A1 policy).

[0187] Figure 3 An example of a wireless communication system 300 supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is illustrated. The wireless communication system 300 may include a PLMN 305 (e.g., PLMN 305-a), a donor base station, an IAB node, and a UE 115 (e.g., UE 115-a). The donor base station may include a donor CU 310 (e.g., donor CU 310-a or donor CU 310-b) and one or more donor DUs 315 (e.g., donor DU 315-a or donor DU 315-b). The IAB node may include an IAB-MT 320 and one or more IAB-DUs 325 (e.g., IAB-DUa 325-a, IAB-DUb 325-b). Figure 3 The device in can be a reference Figure 1 and Figure 2 The wireless communication system 300 may depict an intra-PLMN handover procedure. In some cases, reference Figure 3 The described apparatus may perform techniques for maintaining radio link connectivity at the UE 115 - a throughout the IAB node handover procedure.

[0188] Some wireless communication systems (such as wireless communication system 300) may include one or more IAB devices that may act as nodes of wireless extension of a backhaul network, such as to support multi-hop backhaul. In some cases, an IAB device may refer to an IAB donor base station that is wirelessly connected to other base stations and may have a wired connection to a core network. An IAB donor base station (similar to other base stations) may include a CU (e.g., donor CU 310-a, 310-b) and one or more DUs (e.g., donor DU 315-a, 315-b). In some cases, an IAB device may refer to an IAB node that may include an IAB-MT 320 or a mobile terminal (e.g., CU) and one or more IAB-DUs 325 (e.g., IAB-DUa325-a, IAB-DUb 325-b).

[0189] The CU and one or more DUs may allow the functionality of the device (e.g., IAB node, IAB donor base station) to be split on different units of the device. The CU (e.g., donor CU 310, IAB-MT 320) may support PDCP, radio resource control (RRC), or both, and may control the operation of one or more DUs. The DU (e.g., donor DU 315, IAB-DU 325) may be a logical node including radio link control (RLC), medium access control (MAC), and physical layer (PHY) protocols, and may control one or more sub-IAB nodes, one or more UEs, etc. The interface between the CU and the DU may be referred to as an F1 interface, which may define a higher layer protocol and may support the separation of the control plane (e.g., F1 control plane (F1-C) interface) and the user plane (e.g., F1 user plane (F1-U) interface). The F1 interface may enable the exchange of UE-associated information and non-UE-associated information to provide control plane signaling and user plane signaling for downstream UE 115-a.

[0190] For example, the IAB donor may be connected to the core network (e.g., PLMN 305, AMF) via non-IAB backhaul and may use the IAB donor DU to wirelessly serve one or more UEs 115, one or more IAB nodes, or a combination thereof. In some cases, the UE 115 may communicate with the donor base station via one or more IAB nodes and ultimately communicate with the core network. In such cases, the IAB-MT 320 may be controlled by the donor DU 315, and the UE 115-a may be served by the IAB-DUa 325, wherein the F1 interface supporting communication at the UE 115-a may extend from the IAB-DU 325 to the donor CU 310.

[0191] In some wireless communication systems, the IAB node may be mobile. For example, the IAB node may be installed in a vehicle (e.g., a bus, a train, an airplane, a car) to serve passengers of the vehicle and / or to serve pedestrians outside the vehicle. In such cases, the IAB node may be mobile across a wide geographic area, and thus may be moved to an area served by a different network, an area served by a different base station (of the same or different providers), etc. Therefore, when the IAB node moves, the IAB node may perform a handover procedure. For example, Figure 3 An intra-PLMN handover procedure may be depicted in which an IAB node may perform a handover procedure from a first donor base station (e.g., donor CU 310-a and at least donor DU 315-a) to a second donor base station (e.g., donor CU 310-b and at least donor DU 315-b), both of which are associated with the same core network (e.g., PLMN 305). Because the first donor base station and the second donor base station are associated with the same core network, IP connectivity may be available between the first donor base station and the second donor base station.

[0192] Thus, the IAB-MT 320 may perform a handover to the donor DU 315-b, but it is not sufficient to simply handover the IAB-MT 320 to the donor DU 315-b and still maintain connectivity with the UE 115-a. Instead, it may be necessary to establish a connection between the IAB-DU235 and the target donor base station in order to establish F1 connectivity between the target donor base station and the IAB node that carries control signaling and user plane signaling for the downstream UE 115-a. However, the IAB-DU is logical, so when the IAB-MT performs a handover to the target donor in order to establish a new F1 interface with the target donor, a new logical IAB-DUb 325-b is created. When establishing the IAB-DUb 325-b, the UE 115-a may perform a handover procedure to the IAB-DUb 325-b. However, before the UE 115-a is connected to the IAB-DUb 325-b, the F1 connection between the IAB-DUa 325-a and the donor CU 310-a needs to be maintained. For example, the F1 interface between the IAB-DUa 325-a and the donor CU 310-a can be established via the donor DU 315-b due to the Xn interface IP connectivity, or between the target donor and the source donor. When the UE 115-a and / or one or more other UEs 115 are connected to the IAB-DUa 325-a, the F1 connection between the IAB-DUa 325-a and the donor CU 310-a can be released. Such procedures may be referred to as partial migration.

[0193] However, in some cases, the Xn interface, IP connectivity, etc. between the target donor and the source donor may not be available to support the F1 connection between the IAB-DUa 325-a and the donor CU 310-a via the donor DU 315-b. For example, the source IAB donor and the target IAB donor may be associated with different vendors, so it may be expensive or impossible to dock between the target base station and the source base station. Therefore, when the IAB-MT 320 is handed over to the target base station, the XN connection may be unavailable because there is no IP connectivity between the target donor and the source donor of different vendors. Therefore, the IAB node may lose connection with the backhaul, and thus the UE 115 may experience a radio link failure.

[0194] In order to maintain the connection between the UE 115 and the serving network node (via the F1 interface) during the IAB-MT handover procedure, one or more logical channels (e.g., RRC channels, NAS channels) may be utilized to forward the F1 container between the IAB node serving the UE and the donor base station to establish a "detour" F1 path. For example, an F1 detour path may be established between the IAB-DUa 325-a and the donor CU 310-a via the donor DU 315-b, the donor CU 310-b, the PLMN 305, or a combination thereof. In such cases, the F1 container (e.g., F1-C container) may be forwarded to the donor CU 310-a via the connection (e.g., RRC, NAS, F1) between the IAB node and the donor DU 315-b, the donor CU 310-b, and the PLMN 305. In some cases, donor DU 315-a and donor CU 310-a may be associated with a target donor (e.g., the IAB node is performing a handover to donor CU 310-a and donor DU 315-a), and the IAB node establishes an F1 detour with donor CU 310-a in a make-before-break manner. In some cases, donor DU 315-a and donor CU 310-a may be associated with a source donor (e.g., the IAB node is performing a handover to donor CU 310-b and donor DU 315-b), and the IAB node establishes an F1 detour with donor CU 310-a in a make-before-break manner.

[0195] Figure 4An example of a wireless communication system 400 that supports an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is illustrated. The wireless communication system 400 may include a PLMN 405 (e.g., PLMNs 405-a and 405-b), a donor base station, an IAB node, and a UE 115 (e.g., UE 115-b). The donor base station may include a donor CU 410 (e.g., donor CU 410-a or donor CU 410-b) and one or more donor DUs 415 (e.g., donor DU 415-a or donor 415-b). The IAB node may include an IAB-MT 420 and one or more IAB-DUs 425 (e.g., IAB-DUa 425-a, IAB-DUb 425-b). Figure 4 The device in can be a reference Figures 1 to 3 Examples of corresponding devices described. The wireless communication system 400 may depict inter-PLMN handover procedures. In some cases, reference Figure 4 The described apparatus may perform techniques for maintaining radio link connectivity at UE 115 - b throughout the IAB node handover procedure.

[0196] As reference Figure 2 As described, the IAB node may be mobile, and thus a handover procedure may be performed when the IAB node moves. Figure 4 An inter-PLMN handover procedure may be depicted in which an IAB node may perform a handover from a first donor base station (e.g., donor CU 410-a and at least donor DU 415-a) associated with a first network (e.g., PLMN 405-a) to a second donor base station (e.g., donor CU 410-b and at least donor DU 415-b) associated with a second network (e.g., PLMN 405-b). Because the first donor base station and the second donor base station are associated with different core networks, an Xn interface, IP connectivity, etc. may not be available between the first donor base station and the second donor base station.

[0197] Thus, the IAB-MT 420 may perform a handover to the donor DU 415-b, but the F1 connection (e.g., the F1 connection) between the IAB-DUa and the donor CU 410-a may be disconnected due to the IAB-MT handover. As a result, the IAB node may lose the backhaul connection, and the UE 115-b may detect that the UE 115-b is no longer able to send or receive communications due to the loss of connection (e.g., radio link failure). To mitigate radio link failure at UE 115-b, the wireless communication system 400 may perform procedures for establishing an F1 path between the IAB-DUa425-a and the donor CU 410-a to support the IAB-DUa425-a until after UE 115-b is handed over to the IAB-DUb 425-b, such as a path other than a direct path between the donor CU 410-a and the IAB-DUa 425-a via the donor DU 415-b, because connectivity (e.g., IP connectivity) between the two donors may not exist.

[0198] In order to maintain the connection between the UE and the serving network node (via the F1 interface) during the IAB-MT handover procedure, one or more logical channels (e.g., RRC channels, NAS channels) may be utilized to forward the F1 container associated with the UE 115 between the IAB node and the donor base station to establish a "detour" F1 path. For example, an F1 detour path may be established between the IAB-DUa 425-a and the donor CU 410-a via the donor DU 415-b, the donor CU 410-b, the PLMN 405-b, the PLMN 405-a, or a combination thereof. In such cases, the F1 container (e.g., F1-C container) may be forwarded to the donor CU 410-a via the connection (e.g., RRC, NAS, F1) between the IAB node and the donor DU 415-b, the donor CU 410-b, the PLMN 405-b, and the PLMN 405-a. In some cases, the F1 container may be forwarded toward the donor CU 410-a via the donor DU 415-b, where the detour may be directly to the donor CU 410-a or to the donor CU via one or more core networks (e.g., PLMN 405). In the case where the detour path is via CU410-b to CU 410-a (e.g., via an Xn interface) without passing through the core network, an alternative path or means may be enabled to transmit F1 traffic (e.g., F1-C traffic). In some cases, the donor DU 415-a and the donor CU 410-a may be associated with a target donor (e.g., the IAB node is performing a handover to the donor CU 410-a and the donor DU 415-a), and the IAB node establishes an F1 detour with the donor CU 410-a in a make-before-break manner. In some cases, donor DU 415-a and donor CU 410-a may be associated with a source donor (eg, the IAB node is performing a handoff to donor CU 410-b and donor DU 415-b), and the IAB node establishes an F1 detour with donor CU 410-a in a break-before-make manner.

[0199] Partial migration may refer to, for example, the process of handing over from IAB-MT 420 to donor DU 415-a, donor DU 415-b, or a parent intermediate node between an IAB node and a target donor when the F1 service is supported by IAB-DUa 425-a. In partial migration, the initial F1 interface may be rerouted to the source CU via the target topology. Full migration may refer to the successful handover of UE 115-b to IAB-DUb 425-b. For example, full migration may refer to switching the donor CU endpoint of the F1 connection of the IAB node (or establishing a new F1 connection to a new donor). The initial F1 connection may or may not be released.

[0200] Figure 5An example of a wireless communication system 500 that supports an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is illustrated. The wireless communication system 500 may include one or more AMFs 505, a donor base station, an IAB node, and a UE 115 (e.g., UE 115-c). The donor base station may include a donor CU 510 (e.g., donor CU 510-a or donor CU 510-b) and one or more donor DUs 515 (e.g., donor DU 515-a or donor DU 515-b). The IAB node may include an IAB-MT 520 and one or more IAB-DUs 525 (e.g., IAB-DUa 525-a, IAB-DUb 525-b). Figure 5 The device in can be a reference Figures 1 to 4 The wireless communication system 500 may depict an inter-PLMN handover procedure or an intra-PLMN handover procedure. In some cases, reference Figure 5 The described apparatus may perform techniques for maintaining radio link connectivity at a UE 115 - c throughout an IAB node handover procedure.

[0201] The wireless communication system 500 may include a first donor base station including a donor CU 510-a and at least a donor DU 515-a. Similarly, the wireless communication system 500 may include a second donor base station including a donor CU 510-b and at least a donor DU 515-b. In some cases, the first donor base station and the second donor base station may be supported by the same AMF 505 (e.g., PLMN) or by different AMFs 505. As described herein, the IAB-MT 520 may perform a handover procedure to the target donor base station and may establish an RRC connection with the target donor base station. In order to maintain service at the UE 115-c during such a handover procedure, an F1 detour path may be established before the handover (e.g., connect before disconnect) or after the handover procedure (e.g., disconnect before connect).

[0202] In an example of a break-before-make scenario, the IAB-MT 520 may perform a handover to the donor DU 515-b, and the F1 connectivity between the IAB-DUa 525-a and the donor CU 510-a should be maintained / established before the IAB-DUb 525-b is established and the UE 115-c performs a handover to the IAB-DUb 525-b (e.g., the first donor base station is the source and the second donor base station is the target). However, due to the reference Figure 2 and Figure 3In the described scenario, the F1 interface 530-a may not be maintained or established. Therefore, the IAB node may be configured to encapsulate or decapsulate F1 services (e.g., F1-C services, F1 containers, F1 PDUs) from other services sent by the second donor base station, such as using RRC services (e.g., via an RRC interface), using NAS services (e.g., via a NAS interface), via an F1 interface established with a second donor target base station (e.g., interface 530-c), etc., so as to establish a detour F1 interface. Using the RRC interface, the RRC service and the F1 service may terminate at the donor CU 510-b because the RRC interface may terminate at the donor CU 510-b. Therefore, the F1 service (in either direction, such as to or from the IAB node) may be forwarded to or from the donor CU 510-a using a path via the core network (e.g., one or more AMFs 505 associated with the first donor base station, the second donor base station, or both) or a path between the donor CUs 610. The IAB node may forward the F1 service (e.g., F1-C service) to the donor CU 510-a via the F1 detour 530-b, and / or the donor CU 510-a may forward the F1 service to the IAB node via the F1 detour 530-b. Therefore, the IAB-MT 520 may perform a handover to the donor DU 515-b or the intermediate target parent node, and may establish an RRC interface, a NAS interface, an F1 interface, etc. between the IAB node and the second donor base station. Therefore, a detour path for forwarding the F1 service may be established with the donor CU 510-a, and the UE 115-c will not have a radio link failure. While or after the F1 detour is established, a logical IAB-DUb 525-b may be established and the UE 115-c may perform a handover to the IAB-DUb 525-b. Subsequently, the F1 detour with the donor CU 510-a may be released. Therefore, the detour path may be maintained (only) for a while until the UE 115 - c hands over to the IAB-DUb 525 - b .

[0203] In an example of a make-before-break scenario, the IAB-MT 520 may perform a handover to the donor DU 515-a or an intermediate target parent node, and F1 connectivity between the IAB-DUa 525-a and the donor CU 510-a should be established prior to the handover procedure (e.g., the first donor base station is the target and the second donor base station is the source). The IAB node may be configured to encapsulate or decapsulate the F1 traffic from other traffic sent by the current source donor base station (e.g., the second donor base station), such as using RRC traffic (e.g., via an RRC interface), using NAS traffic (e.g., via a NAS interface), via an F1 interface established with a second donor target base station (e.g., interface 530-c), etc., to establish a detour F1 interface. The IAB node may forward F1 traffic (e.g., F1-C traffic) to the donor CU 510-a via the F1 detour 530-b, and / or the donor CU 510-a may forward F1 traffic to the IAB node via the F1 detour 530-b before and / or during the IAB-MT handover to the first donor base station (e.g., donor DU 515-a). The IAB-MT 520 may perform a handover to the donor DU 515-a, may establish an IAB-DUa 525-a (e.g., when establishing an F1 detour to the donor CU 510-a), and the UE 115-c may be handed over from the IAB-DUb 525-b to the IAB-DUa 525-a. Thus, the IAB-DUa 525-a may establish an F1 interface with the donor CU 510-a without passing through the second donor base station. Therefore, the F1 detour 530-b and the connection with the second donor base station (eg, RRC interface, NAS interface, F1 interface) may be released.

[0204] In some cases, other connections (such as NAS connections) may be utilized in addition to the RRC connection with the second donor base station. The NAS connection terminates at the IAB-MT 520 and AMF 505 associated with at least the second base station. The NAS connection may carry the F1 traffic to the AMF 505, and then the F1 traffic may be routed to the donor 510-c. Additionally or alternatively, the F1 connection between the IAB-DUb 525-b and the donor CU 510-b may be used for F1 detour.

[0205] As described above, the first donor base station and the second donor base station may be supported by the same AMF 505 (e.g., PLMN). In such cases, the F1 service may be forwarded by the donor DU 515-b, the donor CU 510-b, and the AMF 505 to complete the F1 detour between the IAB-DUa 525-a and the donor CU 510-a. Alternatively, the first donor base station and the second donor base station may be supported by different AMFs 505. In such cases, the F1 service may be forwarded by the donor DU 515-b, the donor CU 510-b, the AMF 505 associated with the second base station, and the AMF 505 associated with the first base station to complete the F1 detour between the IAB-DUa 525-a and the donor CU 510-a.

[0206] In some cases, one or more identifiers may be included with the F1 service to ensure that the F1 service is terminated at the intended device (e.g., donor CU 510-a, IAB-DUa 525-a, UE 115-c). For example, in the case of carrying F1 service from donor CU 510-a to an IAB node (and assuming that RRC carries F1 service), donor CU 510-a may transmit F1-related PDUs to AMF 505 associated with donor CU 510-a and may include an identifier of a second donor base station (e.g., base station ID, donor CU 510ID, donor DU 515ID, ID associated with the donor as a whole). AMF 505 may not have an interface with a donor DU and may only interface with a base station (e.g., gNB) base station CU, such as if the base station has a split architecture. In some cases, the donor CU 510-a may send the PDUs in the container to the AMF 505 along with the second donor base station identifier and the IAB-MT 520 identifier. The IAB-MT 520 identifier may include one or more interface protocol identifiers (e.g., NGAP UE ID) or a BAP address (which may be included in a previous handover preparation of the IAB-MT). In some cases, the donor CU 510-a may encapsulate the IAB-MT 520 identifier and the container with the PDUs into a parent container, and may send the parent container to the AMF 505 along with the second donor base station identifier. The AMF 505 associated with the first donor base station may determine the AMF 505 associated with the second donor base station based on the identifier of the second donor base station and, in some cases, based on the IAB-MT identifier. The AMF 505 associated with the second donor base station may be the same as or different from the AMF 505 associated with the first donor base station. In the case where the AMF 505 of the second donor base station is different from the AMF 505 of the first donor base station, the AMF 505 of the first base station may forward the F1 container (or parent container) to the AMF 505 of the second base station together with the second donor base station identifier and, in some cases, the identifier of the IAB-MT 520. The AMF 505 of the second base station may forward the F1 container (or parent container) to the second donor base station based on the second donor base station identifier. In some cases, the AMF 505 of the second base station may optionally indicate the identifier of the IAB-MT 520 to the second donor base station. The second donor base station may recover the identifier of the IAB-MT 520 from the parent container in the AMF message or the AMF 505 message. The second donor base station may forward the F1 container to the IAB node based on the identifier of the IAB-MT 520.

[0207] For example, in the case of carrying F1 traffic from an IAB node to a donor CU 510-a (and assuming that RRC carries F1 traffic), the donor CU 510-b may receive an F1-related PDU from the IAB node and may forward the F1 container together with an identifier of the first donor base station. Similar options and procedures may be applied as described with reference to the F1 forwarding direction from the donor CU 510-a to the IAB-node. For example, an identifier of the IAB-MT 520 and / or an identifier of the first donor base station may be included with the F1 traffic until the F1 traffic arrives at the first donor base station. Alternatively, the identifier of the IAB-MT 520 may not be exchanged along the path. In such a case, the first donor base station may identify the IAB node associated with the F1 traffic from the received F1 PDU.

[0208] In some specific implementations, the identifier (e.g., donor base station identifier, UE identifier, IAB node identifier, AMF identifier) ​​included with the F1 service may be based on which IAB donor is the source of the IAB node handover procedure or the handover preparation procedure and which IAB donor is the target of the IAB node handover procedure or the handover preparation procedure. Additionally or alternatively, the identifier (e.g., donor base station identifier, UE identifier, IAB node identifier, AMF identifier) ​​included with the F1 service may be based on the flow direction of the F1 service, whether the source IAB donor and the target IAB donor are associated with the same or different AMF 505, etc. In some cases, the F1 detour path may be implemented from any handover-related procedure between the two donors. In some specific implementations, establishing the F1-detour path and / or forwarding the F1 service via the F1-detour path may occur before the handover procedure or the handover preparation procedure. In such a scenario, the handover procedure or the handover preparation procedure may occur later in the future, or may not occur at all.

[0209] In some specific implementations, the IAB-MT 520 may perform a handover from the source donor to the target donor via a source-AMF (e.g., S-AMF) associated with the source donor and a target AMF associated with the target T-AMF. During this period, the source IAB donor, the target IAB donor, the migration IAB node, the S-AMF and the T-AMF may exchange a series of handover messages (e.g., handover command, handover request, confirmation, confirmation message, notification message, etc.). The F1 PDU forwarded between the IAB donor (e.g., F1-called end IAB donor) and the migration IAB node may be specifically exchanged between the RAN / AMF or between the AMFs representing the IAB-nodes. However, after the handover procedure to the target AMF and the target IAB donor is successful, the IAB-MT and / or UE context may be released from the source AMF and / or the source IAB donor. For example, upon successful handover, the T-AMF may notify the S-AMF of the handover success. Subsequently, the S-AMF may notify the source donor (e.g., source donor CU) of the success of the handover, and thus the source CU may release any resources reserved by the source CU for serving UE 115-c. Therefore, after completing the handover to the target donor, target core network, etc., the UE context may be deleted at the source CU, S-AMF, etc. However, with such context release procedures, the F1 detour may not be established after the handover because the source network has discarded the context associated with the IAB node, UE 115, etc. In order to maintain the identity of the IAB node and / or UE to which the handover is performed, the RAN / AMF 505 may be configured to retain the identifiers of the IAB node, IAB-MT, UE 115, etc. for a period of time after the handover procedure, which may be used to later identify the IAB node associated with the F1 container forwarded via the F1 detour. In such cases, after the F1-related service forwarding (e.g., F1 detour) is interrupted, the subsequent release of the context and / or identifier of the IAB node may be achieved (via a subsequent context release message).

[0210] F1 traffic may be carried via an IP interface. Thus, the IP address of the IAB node may be dedicated to F1 communications. The IAB node may be configured with an IP address before, during or after the handover procedure. The IP address may be coordinated between donor base stations via one or more AMFs. The IAB node may use a new IP address for F1 related communications along the F1 detour path.

[0211] In some specific implementations, different AMFs may support different functions. Devices (such as donor CU 510) will be connected to AMF based on the capabilities of AMF to support communication at CU. Therefore, capability signaling can be implemented between AMF and base station to allow CU to determine which AMF 505 to connect with. For example, AMF 505 may be configured to send capability signaling to one or more devices (such as other AMF505, donor CU 510, etc.). In some cases, such capability signaling may indicate whether AMF supports forwarding of F1 container (e.g., supports F1 detour). In some cases, such capability signaling may indicate that AMF supports maintaining (e.g., retaining) the context of IAB node after completing the handover procedure, and / or (such as when releasing F1 detour) indicating the ability to subsequently release the context of IAB node. Donor base station (e.g., donor CU 510) may receive one or more capability messages from one or more AMF 505, and may select AMF 505 to be connected based on the ability of AMF 505 to support F1 detour.

[0212] In some cases, the connection between the devices below the donor DU 515 (e.g., the connection between the donor DU 515, the IAB node, and the UE 115) may be a wireless connection. In some cases, the connection between the devices above the donor DU 515 (e.g., the connection between the donor DU 515, the donor CU 510, and the AMF 505) may be a wired connection. The RRC interface (e.g., the RRC protocol layer), the NAS interface (e.g., the NAS protocol layer), the F1 interface, etc. may be referred to as an application protocol and may be independent of the transmission method (e.g., wireless transmission vs. wired transmission). Therefore, the RRC interface, the NAS interface, and the F1 interface may be referred to as a logical channel rather than a physical channel.

[0213] Figure 6 An example of a wireless communication system 600 supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is illustrated. The wireless communication system 600 may include a donor base station, an IAB node, and a UE 115 (e.g., UE 115-d). The donor base station may include a donor CU 610 (e.g., donor CU 610-a or donor CU 610-b) and one or more donor DUs 615 (e.g., donor DU 615-a or donor DU 615-b). The IAB node may include an IAB-MT 620 and one or more IAB-DUs 625 (e.g., IAB-DUa 625-a, IAB-DUb 625-b). Figure 6 The device in can be a reference Figures 1 to 5 The wireless communication system 600 may depict an inter-PLMN handover procedure or an intra-PLMN handover procedure. In some cases, reference Figure 6 The described apparatus may perform techniques for maintaining radio link connectivity at the UE 115 - d throughout the IAB node handover procedure.

[0214] In some implementations, the techniques described herein may be applied when an Xn interface between a first donor base station and a second donor base station is available (e.g., supported) but a connection 605-a between an IAB-DUa and a donor CU 610-a via a donor DU 615-b is not available. In some implementations, the techniques described herein may be applied when a connection 605-a between an IAB-DUa and a donor CU 610-a via a donor DU 615-b is available. In such cases, it may be beneficial to support an additional F1-C path or an alternative F1-C path (e.g., such as by supporting multiple transmission means to increase the robustness of the control plane). In such cases, the F1 detour 605-b may use an IAB node (e.g., an IAB-MT 620 and / or an IAB-DUb 625-b) and a connection (e.g., an RRC connection, an F1 connection) between the donor DU 615-b and the Xn interface between the donor base station. For example, the F1 detour may include an RRC connection between the IAB-MT 620 and the donor CU 610-b and an Xn interface between the donor CU 610-b and the donor CU 610-a. In another example, the F1 detour may include an F1 connection 605-c between the IAB-DUb 625- and the donor CU 610-b and an Xn interface between the donor CU 610-b and the donor CU 610-a. As described herein, a first donor base station (e.g., donor CU 610-a and at least donor DU 615-a) may be a source of a handover procedure and / or a handover preparation procedure, and a second donor base station (e.g., donor CU 610-b and at least donor DU 615-b) may be a target of a handover procedure and / or a handover preparation procedure. Alternatively, the first donor base station (e.g., donor CU 610-a and at least donor DU 615-a) may be the target of the handover procedure and / or the handover preparation procedure, and the second donor base station (e.g., donor CU 610-b and at least donor DU 615-b) may be the source of the handover procedure and / or the handover preparation procedure. In some cases, establishment of the detour F1 path and use of the detour path may occur prior to the handover procedure or the handover preparation procedure, and the handover preparation procedure or the handover procedure may or may not occur in the future (e.g., in this case, the F1-C detour path and forwarding of F1-C traffic via the detour path may be decoupled from the IAB handover).

[0215] Figure 7An example of a process flow 700 for supporting an F1 connection option in an IAB handover scenario in accordance with one or more aspects of the present disclosure is illustrated. The process flow 700 may include a donor base station (e.g., IAB donors 710-a, 710-b), an IAB node 705, and an AMF 715 (e.g., AMF 715-a, 715-b). The donor base station 710 may include a donor CU and one or more donor DUs. The IAB node 705 may include an IAB-MT and one or more IAB-DUs. Figure 7 The device in can be a reference Figures 1 to 6 The process flow 700 may be applicable to inter-PLMN or intra-PLMN handover procedures. In some cases, reference Figure 7 The described apparatus may perform techniques for maintaining radio link connectivity at the UE during the entire IAB node handover procedure. The following alternative aspects may be implemented, where some of the steps are performed in a different order than described or not performed at all. In some cases, the steps may include additional features not mentioned below, or other steps may be added.

[0216] The IAB node 705 may be a migrating (e.g., roaming, active, mobile) node and may serve one or more UEs, one or more other IAB nodes, or a combination thereof. In some cases, the IAB donor 710-a may be a base station at the F1 detour termination as described herein. For example, the IAB donor 710-a may include references to Figure 5 and Figure 6 510-a and DU 515-a and / or CU 610-a and DU 615-a described herein. Similarly, IAB donor 710-b may be a base station (e.g., a non-F1 called end base station) through which the F1 detour is forwarded as described herein. For example, IAB donor 710-b may include references to Figure 5 and Figure 6The donor CU 510-b and the donor DU 515-b and / or the donor CU 610-b and the donor DU 615-b described above may be associated with the IAB donor 710-a. In some cases, the AMF 715-a may be associated with the IAB donor 710-a, and the AMF 715-b may be associated with the IAB donor 710-b. In some implementations, the AMF 715-a and the AMF 715-b may be the same AMF 715 serving both the IAB donor 710-a and the IAB donor 710-b. In some specific implementations, the IAB node 705 may perform a handover procedure from the IAB donor 710-a to the IAB donor 710-b, such that the IAB donor 710-a may be a source base station, the IAB donor 710-b may be a target base station, the AMF 715-a may be a source AMF 715 (e.g., S-AMF), and the AMF 715-b may be a target AMF 715 (e.g., T-AMF). Alternatively, the IAB node 705 may perform a handover procedure from the IAB donor 710-b to the IAB donor 710-a, such that the IAB donor 710-b may be a source base station, the IAB donor 710-a may be a target base station, the AMF 715-b may be a source AMF 715 (e.g., S-AMF), and the AMF 715-a may be a target AMF 715 (e.g., T-AMF). Process flow 700 may depict a process for forwarding F1 traffic from IAB donor 710-a to IAB node 705 via an F1 detour, wherein the F1 detour may be established before or after the IAB node 705 performs a handover procedure to IAB donor 710-a or IAB donor 710-b. In some cases, the F1 detour may be established before or after the IAB node 705 performs a handover preparation procedure with IAB donor 710-a and / or IAB donor 710-b. In some aspects, the handover procedure and / or the handover preparation procedure may or may not occur after the F1 detour is established. The F1 detour path may be based on identifying a donor pair along the detour path. In one example, the donor pair may be a source donor and a target donor associated with the IAB handover.

[0217] At 720, the IAB donor 710-a may send a container (e.g., service, message, signal, channel) having (e.g., encapsulated with, including) an F1 PDU (e.g., F1-C PDU) to the AMF 715-a. At 725, the AMF 715-a may forward the container including the F1 PDU to the AMF 715-b. At 730, the AMF 715-b may forward the container including the F1 PDU to the IAB donor 710-b. At 735, the IAB donor 710-b may forward the container including the F1 PDU to the IAB node 705 (e.g., IAB-MT). To this end, the IAB donor 710-b includes the F1 PDU with a control message (such as an RRC message).

[0218] At 740, the IAB node 740 may decapsulate (e.g., remove, separate) the F1 PDU from the received control message. For example, the IAB-MT of the IAB node 740 may decapsulate the F1 PDU from the RRC message. The IAB-MT may then deliver the F1 PDU to an IAB-DU of the IAB node 740. In some cases, the IAB-DU may be collocated with the IAB-MT.

[0219] Figure 8 An example of a process flow 800 for supporting an F1 connection option in an IAB handover scenario in accordance with one or more aspects of the present disclosure is illustrated. The process flow 800 may include a donor base station (e.g., IAB donor 810-a, 810-b), an IAB node 805, and an AMF 815 (e.g., AMF 815-a, 815-b). The donor base station (e.g., IAB donor 810) may include a donor CU and one or more donor DUs. The IAB node 805 may include an IAB-MT and one or more IAB-DUs. Figure 8 The device in can be a reference Figures 1 to 7 The process flow 800 may be applicable to an inter-PLMN or intra-PLMN handover procedure, a handover preparation procedure, a pre-handover procedure, or a pre-handover preparation procedure (e.g., the handover or handover preparation may or may not occur later). In some cases, reference Figure 8 The described apparatus may perform techniques for maintaining radio link connectivity at the UE during the entire IAB node handover procedure. The following alternative aspects may be implemented, where some of the steps are performed in a different order than described or not performed at all. In some cases, the steps may include additional features not mentioned below, or other steps may be added.

[0220] The IAB node 805 may be a migrating (e.g., roaming, active, mobile) node and may serve one or more UEs, one or more other IAB nodes, or a combination thereof. In some cases, the IAB donor 810-a may be a base station at the F1 detour termination as described herein. For example, the IAB donor 810-a may include references to Figure 5 and Figure 6 510-a and DU 515-a and / or donor CU 610-a and donor DU 615-a described herein. Similarly, IAB donor 810-b may be a base station (e.g., a non-F1 called end base station) through which the F1 detour is forwarded as described herein. For example, IAB donor 810-b may include references to Figure 5 and Figure 6The donor CU 510-b and the donor DU 515-b and / or the donor CU 610-b and the donor DU 615-b described above may be associated with the IAB donor 810-a. In some cases, the AMF 815-a may be associated with the IAB donor 810-a, and the AMF 815-b may be associated with the IAB donor 810-b. In some implementations, the AMF 815-a and the AMF 815-b may be the same AMF 815 serving both the IAB donor 810-a and the IAB donor 810-b. In some specific implementations, the IAB node 805 may perform a handover procedure from the IAB donor 810-a to the IAB donor 810-b, such that the IAB donor 810-a may be a source base station, the IAB donor 810-b may be a target base station, the AMF 815-a may be a source AMF 815 (e.g., S-AMF), and the AMF 815-b may be a target AMF 815 (e.g., T-AMF). Alternatively, the IAB node 805 may perform a handover procedure from the IAB donor 810-b to the IAB donor 810-a, such that the IAB donor 810-b may be a source base station, the IAB donor 810-a may be a target base station, the AMF 815-b may be a source AMF 815 (e.g., S-AMF), and the AMF 815-a may be a target AMF 815 (e.g., T-AMF). Process flow 800 may depict a process for forwarding F1 traffic from IAB node 805 to IAB donor 810-a via an F1 detour, wherein the F1 detour may be established before or after the IAB node 805 performs a handover procedure to IAB donor 810-a or IAB donor 810-b. In some cases, the F1 detour may be established before or after the IAB node 805 performs a handover preparation procedure with IAB donor 810-a and / or IAB donor 810-b. In some aspects, the handover procedure and / or the handover preparation procedure may or may not occur after the F1 detour is established. The F1 detour path may be based on identifying a donor pair along the detour path. In one example, the donor pair may be a source donor and a target donor associated with the IAB handover.

[0221] At 820, the IAB node 805 may encapsulate (e.g., include, combine) the F1 PDU (e.g., F1-C PDU) with the control message (e.g., RRC message). For example, the IAB-DU of the IAB node 805 may deliver the F1 PDU to the IAB-MT of the IAB node 805. Subsequently, the IAB-MT may encapsulate the F1 PDU into the control message. In some cases, the IAB-DU may be arranged in parallel with the IAB-MT.

[0222] At 825, the IAB node 805 (e.g., IAB-MT) may send a control message including the F1 PDU to the IAB donor 810-b. At 830, the IAB donor 810-b may forward the container including the F1 PDU to the AMF 815-b. At 835, the AMF 815-b may forward the container including the F1 PDU to the AMF 815-a. At 840, the AMF 815-a may forward the container including the F1 PDU to the IAB donor 810-a.

[0223] Thus, as described herein, an IAB node 805 (e.g., a migration IAB node) may have an RRC connection with a first base station (e.g., an IAB donor 810-a or an IAB donor 810-b). For example, the IAB node 805 may establish an RRC connection with a first central unit of a first network node. The IAB node may receive an indication of establishing an F1-C connection (e.g., an IAB node to a central unit connection) to a second base station (e.g., an IAB donor 810-a or an IAB donor 810-b) from the first base station via the RRC connection. The IAB node 805 may communicate services associated with the F1-C connection with the second base station via the RRC connection on the link between the IAB node 805 and the first base station.

[0224] The first base station (e.g., a non-F1-detour called end base station, a relay base station) prepares a handover for the IAB-MT with the second base station, wherein the IAB-MT may be handed over to the first base station or the second base station, wherein the handover preparation may occur through an Xn interface or an NG interface (e.g., with AMF815). Preparing the handover of the IAB-MT may include communicating (e.g., sending or receiving) a request for the handover and communicating (e.g., sending or receiving) a response (e.g., ACK, NACK). In the case where the first network node is the target node of the handover, the first base station may receive the request. Alternatively, in the case where the first network node is the source node, the first base station may send the request. In preparing for the handover, the first base station may instruct the IAB node to establish an F1-C connection with the second base station via an RRC connection with the first base station. The first base station may forward services associated with the F1-C connection between the second base station and the IAB node, wherein the F1-C message may be carried in the RRC service on the link between the IAB node and the first base station (e.g., included together with the RRC service).

[0225] The second base station (e.g., an F1-detour called end base station) may prepare a handover for the IAB-MT with the first base station, where the IAB-MT may be handed over to the first base station or the second base station. The second base station may determine an address for forwarding services via the first base station based on the handover preparation, where the services may be associated with an F1-C connection between the second base station and the IAB node. The address may be different from the address associated with the IAB node 805. The second base station may send a PDU of the service to the address. In some cases, the second base station may receive a PDU of the service from the address. The address may be the address of the first base station, such as if the handover preparation is performed on the Xn interface. In some cases, the address may be the address of the AMF 815, such as if the handover preparation is performed via the core network. The first base station may determine the forwarding address to the second base station or the AMF 815 in a similar manner. In a non-handover scenario or in a scenario where the establishment or use of the F1-C detour path occurs before the handover preparation, a reference may be used. Figure 5 Any of the examples described may determine the address by the first base station or the second base station via an exchange of an identifier or an identifier indication. The identifier may be unknown to the handover procedure or the handover preparation procedure. For example, the IAB node may indicate to the first base station (or AMF) the identity of the second base station towards which the F1-C detour path will terminate. This may allow the first base station (or AMF) to identify the second base station, and the forwarding of the F1 service should occur via a detour path using the second base station. The second base station may receive an indicator of the ID of the first base station from the IAB node, the first base station, or the AMF.

[0226] The first base station or the second base station may be a gNB, an IAB donor 810, etc. The IAB node 805 may establish an F1-C connection to the second base station via an RRC connection to the first base station before the handover from the first base station to the second base station. After the IAB node 805 is handed over from the second base station to the first base station, the IAB node 805 may establish an F1-C connection with the second base station via an RRC connection with the first base station. The indication may be a handover command that instructs the IAB node to establish an RRC connection with the first base station, wherein the second base station may be a source base station of the handover procedure, and the first base station may be a target base station of the handover procedure. The indication may be a configuration message that instructs the IAB node 805 to use the RRC connection to communicate services associated with the F1-C connection. The configuration may include the allocation of an IP address for F1-C related communications with the second base station. In some cases, the configuration may be an IP address configuration. The IAB node may select an IP address based on the IP address configuration, and may use the selected address to communicate via the F1 detour. The address may indicate the address of a CU, DU, or IAB node. In some cases, an IP address may be assigned to the IAB node, which may be used as a source IP address when the IAB node transmits packets, and which may specify the destination IP address of the IAB node when the IAB node receives packets. The configuration message may be a Boolean value that the IAB node may use the RRC connection to exchange F1-C traffic. For example, in some cases, if the node does not receive the configuration message, the network node may not transmit F1-C traffic on its RRC connection.

[0227] The service associated with the F1-C connection may be included in a NAS container associated with the RRC connection (e.g., in the RRC connection). The service associated with the F1-C connection may refer to an F1-application protocol (F1-AP) message, a stream control transmission protocol (SCTP) packet, or an IP packet of an existing F1-C connection, or the service may be exchanged to establish or reestablish an F1-C connection between the IAB node 805 and the second base station. The communication service may include sending service, wherein the IAB node 805 may encapsulate the F1-C PDU into the PDU of the RRC connection (or some other connection), and may send the encapsulated PDU to the first base station. In some cases, the communication service may include receiving service, wherein the IAB node 805 may receive the PDU of the RRC connection (or some other connection) from the first base station, and decapsulate the F1-C PDU from the encapsulated PDU. The IAB node 805 may include an identifier of the second base station together with the communication associated with the F1-C connection.

[0228] The handover preparation (e.g., performed by the first base station, the second base station, the IAB node 805, the core network node) may be performed on a base station interface (e.g., an Xn interface) or an interface associated with the core network node (e.g., an NG interface). The handover preparation performed by the second base station may be performed on a base station interface (e.g., an Xn interface) with the first base station, wherein the second base station may determine the address for forwarding traffic to be the address of the first base station. The handover preparation performed by the second base station may be performed on an interface (e.g., an NG interface) with the core network node, wherein the second base station may determine the address for forwarding traffic to be the address of the core network node.

[0229] Forwarding (e.g., sending or receiving) services may be performed on a base station interface (e.g., an Xn interface) with the second base station or on an interface (e.g., an NG interface) via a core network node. The first base station may determine an identifier of the second base station, a core network node for an IAB node, etc. based on handover preparation, wherein forwarding a PDU associated with an F1-C connection via a core network node may include at least a second base station identifier. The first base station may include an identifier (e.g., UE ID) associated with an IAB node 805 (e.g., an IAB-MT identifier, an IAB-DU identifier, a UE identifier, a core network identifier) ​​and the forwarded PDU together. In some cases, the second base station may configure an IP address for the IAB node 805, which is associated with an F1-C connection with the second base station.

[0230] Forwarding (e.g., sending or receiving) a service to a second base station (e.g., directly or via a core network node) may include using a UE-associated message or a non-UE-associated message, wherein the UE-associated message may be associated with the IAB-MT. In some cases, the first base station may send (or receive) a request to forward the PDU of the F1-C connection to the second base station or the core network node. The first base station may forward the PDU based on receiving (or sending) a confirmation message (respectively). In some specific implementations, the first base station may provide (e.g., send) an indication that the forwarding of the F1-C PDU is interrupted to the second base station or the core network node via which the F1-C PDU is forwarded. The indication may include an indication of releasing an identifier associated with the IAB-MT.

[0231] In some cases, the first base station may receive an indication of capability from a core network node associated with forwarding F1-C traffic. The base station may send an F1-C PDU via a core network node based at least in part on receiving the capability or based on the core network node being able to forward F1-C traffic. The first base station may communicate an IP address configuration or a request for an IP address configuration for use by the IAB node (or via a management entity) in F1-C related communications with the second base station. The first base station may configure an IP address for the IAB node, which is used for an F1-C connection with the second base station.

[0232] A core network node (e.g., a core network management entity, an AMF, a PLMN) may receive a first message from a first network node, the first message including an indicator for forwarding an F1-C container, a UE ID, and a target base station ID. The core network node may forward the first message to a second network node (e.g., a first base station, a second base station). The core network node may cache the first network node and the second network node of the first message together with the UE ID and the F1-C container indicator. Caching may include collecting, classifying, and / or storing data in a cache memory. The core network node may forward one or more other messages between the first network node and the second network node based on the cached information, the one or more other messages carrying the F1-C container and indicating the UE ID.

[0233] The first network node may be an AMF, an MME, etc. The first network node or the second network node may be a second core network node. The first message may include an indication of a handover procedure (e.g., a handover command, a handover request). The first message may include a request to create a UE context. The first message may include a handover request confirmation. The first message may include a response to creating a UE context. The first message may include a notification of a handover procedure. The first message may include a notification of receiving a handover indication. The first message may include a confirmation associated with the handover notification. The first message may include an indicator of completing the UE context release.

[0234] The first message may include a request for forwarding F1-C related services to or from a base station indicated by a target base station ID, and the core network node may confirm the request. The core network node may forward one or more other messages based on the confirmation of the request. The target base station ID may be the ID of the source base station, and the UE will be handed over from the source base station to the target base station. The target base station ID may be the ID of the target base station, and the UE will be handed over from the source base station to the target base station. The UE ID may be associated with the IAB-MT.

[0235] In some cases, the first network node may be an IAB node, wherein the first message received from the first network node or one or more other messages exchanged with the first network node may be carried via a NAS connection. The UE ID may be indicated by the IAB node that sent or received the message. The second network node may be an IAB node, wherein the first message forwarded to the second network node or one or more other messages exchanged with the second network node may be carried via a NAS connection. The UE ID may be indicated by the IAB node that sent or received the message.

[0236] In some cases, the core network node may provide a capability for the core network node to forward an F1-C container to a first network node or a second network node. The core network node may receive a first message or one or more other messages based on providing the capability. The core network node may receive a capability for forwarding an F1-C container from a second network node. The core network node may forward the first message or one or more other messages to the second network node based on receiving the capability. The CN management entity may receive a release message from the first network node or the second network node, the release message including a UE ID and an F1-C container indicator, and the core network node may release the cached information based on the release message. The core network node may forward the release message to the other of the first network node or the second network node.

[0237] Fig. 9 A block diagram 900 of a device 905 supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is shown. The device 905 may be an example of aspects of a network entity 105 as described herein. The device 905 may include a receiver 910, a transmitter 915, and a communication manager 920. The device 905 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0238] The receiver 910 may provide means for obtaining (e.g., receiving, determining, identifying) information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). The information may be communicated to other components of the device 905. In some aspects, the receiver 910 may support obtaining information by receiving signals via one or more antennas. Additionally or alternatively, the receiver 910 may support obtaining information by receiving signals via one or more wired (e.g., electrical, optical fiber) interfaces, wireless interfaces, or any combination thereof.

[0239] The transmitter 915 may provide means for outputting (e.g., transmitting, providing, conveying, transmitting) information generated by other components of the device 905. For example, the transmitter 915 may output information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) (such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units)). In some aspects, the transmitter 915 may support outputting information by sending signals via one or more antennas. Additionally or alternatively, the transmitter 915 may support outputting information by sending signals via one or more wired (e.g., electrical, optical fiber) interfaces, wireless interfaces, or any combination thereof. In some aspects, the transmitter 915 and the receiver 910 may be co-located in a transceiver, which may include a modem or be coupled to a modem.

[0240] The communication manager 920, the receiver 910, the transmitter 915, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the F1 connection option in the IAB handover scenario as described herein. For example, the communication manager 920, the receiver 910, the transmitter 915, or various combinations thereof or components thereof may support methods for performing one or more of the functions described herein.

[0241] In some aspects, the communication manager 920, the receiver 910, the transmitter 915, or various combinations or components thereof may be implemented in hardware (e.g., in a communication management circuit system). The hardware may include a processor, a DSP, a CPU, an ASIC, an FPGA or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof that is configured to or otherwise supports means for performing the functions described herein. In some aspects, a processor and a memory coupled to the processor may be configured (e.g., by the processor executing instructions stored in the memory) to perform one or more of the functions described herein.

[0242] Additionally or alternatively, in some aspects, the communication manager 920, the receiver 910, the transmitter 915, or various combinations or components thereof may be implemented in code executed by a processor (e.g., as communication management software or firmware). If implemented in code executed by a processor, the functionality of the communication manager 920, the receiver 910, the transmitter 915, or various combinations or components thereof may be performed by a general purpose processor (e.g., configured as or otherwise supporting means for performing the functionality described herein), a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices.

[0243] In some aspects, the communication manager 920 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with the receiver 910, the transmitter 915, or both. For example, the communication manager 920 may receive information from the receiver 910, transmit information to the transmitter 915, or be integrated with the receiver 910, the transmitter 915, or both to obtain information, output information, or perform various other operations as described herein.

[0244] According to the examples disclosed herein, the communication manager 920 may support wireless communication at the IAB node. For example, the communication manager 920 may be configured to or otherwise support a component for establishing an RRC connection with a first central unit of a first network node. The communication manager 920 may be configured to or otherwise support a component for receiving from the first network node an indication that the IAB node will establish an IAB node to central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The communication manager 920 may be configured to or otherwise support a component for communicating with the second network node via an IAB node to central unit connection using the RRC connection between the IAB node and the first network node.

[0245] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 920 may support wireless communication at the first network node. For example, the communication manager 920 may be configured to or otherwise support a component for establishing an RRC connection with an IAB node, wherein the RRC connection is between a first central unit of the first network node and the IAB node. The communication manager 920 may be configured to or otherwise support a component for sending an indication to the IAB node that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The communication manager 920 may be configured to or otherwise support a component for relaying (e.g., forwarding) traffic via an IAB node-to-central unit connection between the second network node and the IAB node using the RRC connection between the IAB node and the first network node.

[0246] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 920 may support wireless communication at the first network node. For example, the communication manager 920 may be configured to or otherwise support a component for receiving an indication of a handover of the IAB node between the second network node and the first network node. The communication manager 920 may be configured to or otherwise support a component for determining, based on the indication, an address for forwarding traffic from the first network node to the IAB node via the second network node using an IAB node-to-central unit connection between the first central unit of the first network node and the IAB node, wherein the address is different from the IAB node address of the indicating IAB node. The communication manager 920 may be configured to or otherwise support a component for sending traffic to an address determined by the first network node.

[0247] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 920 may support wireless communication at a core network node. For example, the communication manager 920 may be configured to or otherwise support a component for receiving control information from a first network node, the control information indicating that the core network node will forward one or more containers of the IAB node of the IAB node to the central unit connection, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with the second network node. The communication manager 920 may be configured to or otherwise support a component for sending one or more containers to the second network node based on the second identifier being included in the control information. The communication manager 920 may be configured to or otherwise support a component for caching control information, a first identifier, a second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward one or more containers. The communication manager 920 may be configured to or otherwise support a component for sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0248] By including or configuring a communication manager 920 according to aspects as described herein, a device 905 (e.g., a processor controlling or otherwise coupled to a receiver 910, a transmitter 915, a communication manager 920, or a combination thereof) may support techniques for more efficiently utilizing communication resources.

[0249] Fig.10A block diagram 1000 of a device 1005 supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is shown. The device 1005 may be an example of aspects of the device 905 or the network entity 105 as described herein. The device 1005 may include a receiver 1010, a transmitter 1015, and a communication manager 1020. The device 1005 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0250] The receiver 1010 may provide means for obtaining (e.g., receiving, determining, identifying) information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). The information may be communicated to other components of the device 1005. In some aspects, the receiver 1010 may support obtaining information by receiving signals via one or more antennas. Additionally or alternatively, the receiver 1010 may support obtaining information by receiving signals via one or more wired (e.g., electrical, optical fiber) interfaces, wireless interfaces, or any combination thereof.

[0251] The transmitter 1015 may provide means for outputting (e.g., transmitting, providing, conveying, transmitting) information generated by other components of the device 1005. For example, the transmitter 1015 may output information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack) (such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units)). In some aspects, the transmitter 1015 may support outputting information by sending signals via one or more antennas. Additionally or alternatively, the transmitter 1015 may support outputting information by sending signals via one or more wired (e.g., electrical, optical fiber) interfaces, wireless interfaces, or any combination thereof. In some aspects, the transmitter 1015 and the receiver 1010 may be co-located in a transceiver, which may include a modem or be coupled to a modem.

[0252] The device 1005 or its various components may be examples of components for performing various aspects of the F1 connection option in the IAB handover scenario as described herein. For example, the communication manager 1020 may include an RRC connection component 1025, an IAB node to central unit connection component 1030, a network node communication component 1035, a service relay component 1040, a handover procedure component 1045, a service address component 1050, a cache component 1055, a network node capability component 1060, or any combination thereof. The communication manager 1020 may be an example of various aspects of the communication manager 920 as described herein. In some aspects, the communication manager 1020 or its various components may be configured to use or otherwise cooperate with the receiver 1010, the transmitter 1015, or both to perform various operations (e.g., receive, obtain, monitor, output, send). For example, the communications manager 1020 may receive information from the receiver 1010, transmit information to the transmitter 1015, or be integrated with the receiver 1010, the transmitter 1015, or both to obtain information, output information, or perform various other operations as described herein.

[0253] According to aspects as disclosed herein, the communication manager 1020 may support wireless communication at an IAB node. The RRC connection component 1025 may be configured to or otherwise support a component for establishing an RRC connection with a first central unit of a first network node. The IAB node to central unit connection component 1030 may be configured to or otherwise support a component for receiving an indication from the first network node that the IAB node will establish an IAB node to central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The network node communication component 1035 may be configured to or otherwise support a component for communicating with the second network node via an IAB node to central unit connection using the RRC connection between the IAB node and the first network node.

[0254] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1020 may support wireless communication at the first network node. The IAB node to central unit connection component 1030 may be configured as or otherwise support components for participating in establishing a communication path between the IAB node and the central unit of the second network node via the core network node, wherein the communication path is an IAB node to central unit connection. The service relay component 1040 may be configured as or otherwise support components for forwarding services between the IAB node and the central unit via the core network node using the IAB node to central unit connection.

[0255] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1020 may support wireless communication at the first network node. The RRC connection component 1025 may be configured to or otherwise support a component for establishing an RRC connection with an IAB node, wherein the RRC connection is between a first central unit of the first network node and the IAB node. The IAB node to central unit connection component 1030 may be configured to or otherwise support a component for sending an indication to the IAB node that the IAB node will establish an IAB node to central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The service relay component 1040 may be configured to or otherwise support a component for relaying (e.g., forwarding) a service via an IAB node to central unit connection between the second network node and the IAB node using the RRC connection between the IAB node and the first network node.

[0256] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1020 may support wireless communication at the first network node. The handover procedure component 1045 may be configured to or otherwise support a component for receiving an indication of a handover of the IAB node between the second network node and the first network node. The service address component 1050 may be configured to or otherwise support a component for determining, based on the indication, an address for forwarding the service from the first network node to the IAB node via the second network node using the IAB node-to-central unit connection between the first central unit of the first network node and the IAB node, wherein the address is different from the IAB node address of the indicating IAB node. The network node communication component 1035 may be configured to or otherwise support a component for sending the service to an address determined by the first network node.

[0257] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1020 may support wireless communication at a core network node. The service relay component 1040 may be configured to or otherwise support a component for receiving control information from a first network node, the control information indicating that the core network node will forward one or more containers of the IAB node to the central unit connection of the IAB node, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with the second network node. The network node communication component 1035 may be configured to or otherwise support a component for sending one or more containers to the second network node based on the second identifier being included in the control information. The cache component 1055 may be configured to or otherwise support a component for caching control information, a first identifier, a second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward one or more containers. The network node capability component 1060 may be configured to or otherwise support a component for sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0258] Fig.11 A block diagram 1100 of a communication manager 1120 supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is shown. The communication manager 1120 may be an example of aspects of the communication manager 920, the communication manager 1020, or both as described herein. The communication manager 1120 or its various components may be examples of components for performing various aspects of the F1 connection option in an IAB handover scenario as described herein. For example, the communication manager 1120 may include an RRC connection component 1125, an IAB node to central unit connection component 1130, a network node communication component 1135, a service relay component 1140, a handover procedure component 1145, a service address component 1150, a cache component 1155, a network node capability component 1160, a decapsulation component 1165, a relay request component 1170, a confirmation component 1175, a service interruption component 1180, an IP address component 1185, an identifier determination component 1190, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses), which communication may include communication within a protocol layer of a protocol stack, communication associated with a logical channel of a protocol stack (e.g., between protocol layers of a protocol stack, within a device, component, or virtualized component associated with the network entity 105, between devices, components, or virtualized components associated with the network entity 105), or any combination thereof.

[0259] According to aspects as disclosed herein, the communication manager 1120 may support wireless communication at the IAB node. The RRC connection component 1125 may be configured to or otherwise support a component for establishing an RRC connection with a first central unit of a first network node. The IAB node to central unit connection component 1130 may be configured to or otherwise support a component for receiving from the first network node an indication that the IAB node will establish an IAB node to central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The network node communication component 1135 may be configured to or otherwise support a component for communicating with the second network node via an IAB node to central unit connection using the RRC connection between the IAB node and the first network node.

[0260] In some aspects, the IAB node to central unit connection component 1130 may be configured as or otherwise support means for establishing an IAB node to central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node. In some aspects, the handover procedure component 1145 may be configured as or otherwise support means for performing a handover procedure from the first network node to the second network node after establishing the IAB node to central unit connection.

[0261] In some aspects, handover procedure component 1145 may be configured as or otherwise support means for performing a handover procedure from the second network node to the first network node. In some aspects, IAB node to central unit connection component 1130 may be configured as or otherwise support means for establishing an IAB node to central unit connection with a second central unit of the second network node via an RRC connection between the IAB node and the first network node after the handover procedure.

[0262] In some aspects, to support receiving an indication, the handover procedure component 1145 may be configured to or otherwise support a component for receiving a handover command prior to establishing an RRC connection with a first central unit of a first network node, the handover command indicating that the IAB node is to establish an RRC connection with the first central unit of the first network node, wherein the first network node is a target node for the handover and the second network node is a source node for the handover, and wherein the handover command is the indication.

[0263] In some aspects, to support receiving the indication, the network node communication component 1135 may be configured to or otherwise support means for receiving a configuration message instructing the IAB node to communicate traffic via an IAB node-to-central unit connection with a second central unit of a second network node using an RRC connection between the IAB node and the first network node, wherein the configuration message is the indication.

[0264] In some aspects, the configuration message includes an Internet Protocol address configuration; and the IAB node selects an Internet Protocol address based on the Internet Protocol address configuration and communicates via the IAB node to central unit connection with a second central unit of the second network node using the Internet Protocol address.

[0265] In some aspects, to support communications via the IAB node to central unit connection, the network node communicating component 1135 may be configured or otherwise support means for communicating traffic via the IAB node to central unit connection, wherein the traffic is included in a non-access stratum container corresponding to the RRC connection.

[0266] In some aspects, to support communications via the IAB node to central unit connection, the network node communication component 1135 may be configured to or otherwise support components for communicating traffic via the IAB node to central unit connection, wherein the traffic includes F1-application protocol messages, flow control transmission protocol messages, or Internet protocol packets.

[0267] In some aspects, to support communications via the IAB node to central unit connection, the network node communicating component 1135 may be configured or otherwise support means for communicating traffic to establish or reestablish an IAB node to central unit connection with a second central unit of a second network node.

[0268] In some aspects, to support communication via the IAB node to central unit connection, the network node communication component 1135 may be configured to or otherwise support means for sending an F1-C protocol data unit for a second network node to a first network node using an RRC connection, wherein the F1-C protocol data unit is encapsulated in a protocol data unit corresponding to the RRC connection.

[0269] In some aspects, to support communication via the IAB node to the central unit connection, the network node communication component 1135 may be configured or otherwise support means for receiving, from the first network node, an F1-C protocol data unit from the second network node using an RRC connection. In some aspects, to support communication via the IAB node to the central unit connection, the decapsulation component 1165 may be configured or otherwise support means for decapsulating the F1-C protocol data unit from the protocol data unit corresponding to the RRC connection.

[0270] In some aspects, communicating via the IAB node to the central unit connection using the RRC connection includes an identifier associated with the second network node.

[0271] In some aspects, the first network node is a first base station or a first IAB donor node, or the second network node is a second base station or a second IAB donor node.

[0272] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1120 may support wireless communication at the first network node. In some aspects, the IAB node to central unit connection component 1130 may be configured as or otherwise support a component for participating in establishing a communication path between the IAB node and the central unit of the second network node via the core network node, wherein the communication path is an IAB node to central unit connection. In some aspects, the service relay component 1140 may be configured as or otherwise support a component for forwarding services between the IAB node and the central unit via the core network node using the IAB node to central unit connection.

[0273] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1120 may support wireless communication at the first network node. In some aspects, the RRC connection component 1125 may be configured to or otherwise support a component for establishing an RRC connection with an IAB node, wherein the RRC connection is located between a first central unit of the first network node and the IAB node. In some aspects, the IAB node to central unit connection component 1130 may be configured to or otherwise support a component for sending an indication to the IAB node that the IAB node will establish an IAB node to central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The service relay component 1140 may be configured to or otherwise support a component for relaying (e.g., forwarding) a service via an IAB node to central unit connection between the second network node and the IAB node using the RRC connection between the IAB node and the first network node.

[0274] In some aspects, the handover procedure component 1145 may be configured as or otherwise support means for performing a handover procedure to handover the IAB node from a first network node to a second network node after establishing an IAB node to central unit connection, wherein the first network node is a source node for the handover and the second network node is a target node for the handover procedure.

[0275] In some aspects, the handover procedure component 1145 may be configured as or otherwise support means for performing a handover procedure to handover the IAB node from the second network node to the first network node prior to establishing the IAB node to central unit connection, wherein the first network node is a target node for the handover and the second network node is a source node for the handover procedure.

[0276] In some aspects, handover procedures component 1145 may be configured or otherwise support means for preparing a handover of an IAB node from a second network node to a first network node or preparing a handover of the IAB node from a first network node to a second network node.

[0277] In some aspects, the identifier determining component 1190 may be configured to or otherwise support means for determining a first identifier of a second network node and a second identifier of a core network node associated with the IAB node based on handover preparation, wherein traffic is relayed via the core network node through the IAB node to the central unit connection based on the first identifier or the second identifier.

[0278] In some aspects, to prepare for the handover, the first node is configured to prepare for the handover via a base station interface or a core network node interface.

[0279] In some aspects, to support sending an indication, the handover procedure component 1145 may be configured to or otherwise support a component for sending a handover command instructing the IAB node to establish an RRC connection with a first central unit of a first network node, wherein the first network node is a target node for the handover and the second network node is a source node for the handover, and wherein the handover command is the indication.

[0280] In some aspects, to support sending the indication, the network node communication component 1135 may be configured to or otherwise support means for sending a configuration message instructing the IAB node to communicate traffic via an IAB node-to-central unit connection with a second central unit of a second network node using an RRC connection between the IAB node and the first network node, wherein the configuration message is the indication.

[0281] In some aspects, the configuration message includes an Internet Protocol address configuration for selecting an Internet Protocol address for communicating via the IAB node-to-central unit connection with the second central unit of the second network node.

[0282] In some aspects, relay request component 1170 may be configured as or otherwise support means for receiving a request from a second network node, an IAB node, or a core network node to relay traffic via an IAB node to a central unit connection. In some aspects, confirmation component 1175 may be configured as or otherwise support means for sending a positive confirmation in response to the request, wherein the first network node relays traffic based on sending the positive confirmation.

[0283] In some aspects, service interruption component 1180 may be configured as or otherwise support means for sending a message to a second network node or a core network node via which the service is relayed indicating that the service is interrupted.

[0284] In some aspects, the message includes an indication to release an identifier associated with the IAB node.

[0285] In some aspects, network node capability component 1160 may be configured or otherwise support means for receiving a message indicating the capability of a core network node to relay traffic via an IAB node to central unit connection, wherein traffic is relayed via the core network node based on the capability of the core network node.

[0286] In some aspects, the network node communicating component 1135 may be configured as or otherwise support means for communicating with the second network node an internet protocol address configuration for an IAB node to central unit connection or a request for an internet protocol address configuration for an IAB node to central unit connection.

[0287] In some aspects, IP address component 1185 may be configured as or otherwise support means for configuring an Internet Protocol address for the IAB node for an IAB node-to-central unit connection with a second central unit of a second network node.

[0288] In some aspects, the traffic includes a first identifier of the second network node, a second identifier of a core network node associated with the IAB node, or a third identifier of the IAB node.

[0289] In some aspects, traffic is relayed using a UE associated message or a non-UE associated message, and the UE associated message is associated with an IAB node.

[0290] In some aspects, the traffic is relayed via a base station interface or a core network node interface with the second network node.

[0291] In some aspects, the traffic is included in a non-access stratum container corresponding to the RRC connection.

[0292] In some aspects, the traffic comprises F1-application protocol messages, flow control transmission protocol messages, or internet protocol packets.

[0293] In some aspects, the traffic relates to establishing or re-establishing an IAB node-to-central unit connection with a second central unit of a second network node.

[0294] In some aspects, the first network node is a first base station or a first IAB donor node, or the second network node is a second base station or a second IAB donor node.

[0295] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1120 may support wireless communication at the first network node. The handover procedure component 1145 may be configured to or otherwise support a component for receiving an indication of a handover of the IAB node between the second network node and the first network node. The service address component 1150 may be configured to or otherwise support a component for determining, based on the indication, an address for forwarding the service from the first network node to the IAB node via the second network node using the IAB node-to-central unit connection between the first central unit of the first network node and the IAB node, wherein the address is different from the IAB node address of the indicating IAB node. In some aspects, the network node communication component 1135 may be configured to or otherwise support a component for sending the service to an address determined by the first network node.

[0296] In some aspects, the handover procedure component 1145 may be configured as or otherwise support means for performing a handover procedure to handover the IAB node from a first network node to a second network node prior to establishing the IAB node to central unit connection, wherein the first network node is a source node for the handover and the second network node is a target node for the handover procedure.

[0297] In some aspects, the handover procedure component 1145 may be configured as or otherwise support means for performing a handover procedure to handover the IAB node from the second network node to the first network node after establishing the IAB node to central unit connection, wherein the first network node is a target node for the handover and the second network node is a source node for the handover procedure.

[0298] In some aspects, handover procedures component 1145 may be configured or otherwise support means for preparing a handover of an IAB node from a second network node to a first network node or preparing a handover of the IAB node from a first network node to a second network node.

[0299] In some aspects, the identifier determining component 1190 may be configured as or otherwise support means for determining a first identifier of the first network node and a second identifier of a core network node associated with the IAB node based on handover preparation, wherein traffic is sent via the core network node based on the first identifier or the second identifier.

[0300] In some aspects, the first network node prepares for a handover via a base station interface with a second network node, and the first network node determines to send traffic via the second network node based on an address of the second network node.

[0301] In some aspects, the first network node prepares for handover via a core network node interface.In some aspects, the first network node determines to send traffic via the core network node based on an address of the core network node.

[0302] In some aspects, the service relay component 1140 may be configured as or otherwise support a means for sending a request to the second network node or the core network node that the second network node relay the service via the IAB node to the central unit connection. In some aspects, the confirmation component 1175 may be configured as or otherwise support a means for receiving a positive confirmation in response to the request, wherein the service is sent based on the positive confirmation, and the first network node receives the service based on the positive confirmation.

[0303] In some aspects, the service interruption component 1180 may be configured as or otherwise support means for sending a message to a second network node or a core management network node via which the service is sent indicating that the service is interrupted.

[0304] In some aspects, the message includes an indication to release an identifier associated with the IAB node.

[0305] In some aspects, network node capability component 1160 may be configured or otherwise support means for receiving a message indicating the capability of a core network node to relay traffic via an IAB node to central unit connection, wherein traffic is sent via the core network node based on the capability of the core network node.

[0306] In some aspects, IP address component 1185 may be configured as or otherwise support means for communicating with the second network node an internet protocol address configuration or a request for an internet protocol address configuration for an IAB node to connect to the central unit.

[0307] In some aspects, IP address component 1185 may be configured as or otherwise support means for configuring an Internet Protocol address for the IAB node for an IAB node-to-central unit connection between the first central unit of the first network node and the IAB node.

[0308] In some aspects, the network node communicating component 1135 may be configured or otherwise support means for receiving a protocol data unit for traffic from the address.

[0309] In some aspects, the traffic includes a first identifier of the first network node, a second identifier of a core network node associated with the IAB node, or a third identifier of the IAB node.

[0310] In some aspects, the traffic is sent using a UE associated message or a non-UE associated message, and the UE associated message is associated with the IAB node.

[0311] In some aspects, the traffic comprises F1-application protocol messages, flow control transmission protocol messages, or internet protocol packets.

[0312] In some aspects, traffic is sent to establish or re-establish an IAB node-to-central unit connection with a first central unit of a first network node.

[0313] In some aspects, the first network node is a first base station or a first IAB donor node, or the second network node is a second base station or a second IAB donor node.

[0314] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1120 may support wireless communication at a core network node. In some aspects, the service relay component 1140 may be configured to or otherwise support a component for receiving control information from a first network node, the control information indicating that the core network node will forward one or more containers of the IAB node of the IAB node to the central unit connection, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with the second network node. In some aspects, the network node communication component 1135 may be configured to or otherwise support a component for sending one or more containers to the second network node based on the second identifier being included in the control information. The cache component 1155 may be configured to or otherwise support a component for caching control information, a first identifier, a second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward one or more containers. The network node capability component 1160 may be configured to or otherwise support a component for sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0315] In some aspects, to support receiving control information, relay request component 1170 may be configured or otherwise support means for receiving a request to forward one or more containers to or from a second network node based on the second identifier being included in the control information.

[0316] In some aspects, confirmation component 1175 may be configured or otherwise support means for sending a confirmation message in response to a request.

[0317] In some aspects, to support sending one or more containers or one or more other containers, the network node communicating component 1135 may be configured or otherwise support means for sending one or more containers or one or more other containers based on the confirmation message.

[0318] In some aspects, the network node capability component 1160 may be configured to or otherwise support means for sending a message indicating the ability of the core network node to relay traffic to the first network node or the second network node via the IAB node to central unit connection, wherein communication of control information, one or more containers, or one or more other containers is based on the capabilities of the core network node.

[0319] In some aspects, the network node capability component 1160 may be configured to or otherwise support means for receiving a message indicating an ability of a second network node to relay traffic via an IAB node to a central unit connection, wherein control information, one or more containers, or one or more other containers are relayed to the second network node based on the ability of the second network node.

[0320] In some aspects, the service interruption component 1180 may be configured to or otherwise support means for receiving a release message from the first network node or the second network node, the release message instructing the core network node to release the buffered information, wherein the release message includes an identifier associated with one or more containers or the first identifier.

[0321] In some aspects, traffic relay component 1140 may be configured as or otherwise support means for relaying a release message to the first network node or the second network node.

[0322] In some aspects, the first network node is a source node for a handover procedure in which the IAB node is handed over from the first network node to the second network node.

[0323] In some aspects, the second network node is a source node for a handover procedure in which the IAB node is handed over from the second network node to the first network node.

[0324] In some aspects, the control information, one or more containers, or one or more other containers are included in a non-access stratum message.

[0325] In some aspects, the first network node corresponds to a network node type, or the second network node corresponds to a network node type, which is an IAB node type.

[0326] In some aspects, the first identifier associated with the IAB node is indicated by the first network node or the second network node.

[0327] In some aspects, the control information includes a handover required indicator, a request to create a UE context, a handover request confirmation indicator, a response to an indication to create a UE context, a notification of a handover procedure, a notification of receipt of a notification of a handover procedure, a confirmation associated with a notification of a handover procedure, or an indication of completion of release of the UE context.

[0328] In some aspects, the core network node is an access and mobility management function or a mobility management entity.

[0329] In some aspects, the first network node is a first base station or a first IAB donor node, or the second network node is a second base station or a second IAB donor node.

[0330] In some aspects, the first network node or the second network node is a second core network node.

[0331] Fig.12 A diagram of a system 1200 of a device 1205 supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is shown. The device 1205 may be an example of a device 905, a device 1005, or a network entity 105 as described herein, or include components thereof. The device 1205 may communicate with one or more network entities 105, one or more UEs 115, or any combination thereof, which may include communication through one or more wired interfaces, through one or more wireless interfaces, or any combination thereof. The device 1205 may include components that support output and obtain communication, such as a communication manager 1220, a transceiver 1210, an antenna 1215, a memory 1225, a code 1230, and a processor 1235. These components may be electronically communicated or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., bus 1240).

[0332] The transceiver 1210 may support bidirectional communication via a wired link, a wireless link, or both, as described herein. In some aspects, the transceiver 1210 may include a wired transceiver and may communicate bidirectionally with another wired transceiver. Additionally or alternatively, in some aspects, the transceiver 1210 may include a wireless transceiver and may communicate bidirectionally with another wireless transceiver. In some aspects, the device 1205 may include one or more antennas 1215 that may be capable of (e.g., concurrently) sending or receiving wireless transmissions. The transceiver 1210 may also include a modem for modulating a signal, for providing the modulated signal for transmission (e.g., via one or more antennas 1215, via a wired transmitter), for receiving the modulated signal (e.g., from one or more antennas 1215, from a wired receiver), and for demodulating a signal. The transceiver 1210 or the transceiver 1210 and one or more antennas 1215 or a wired interface (where applicable) may be an example of a transmitter 915, a transmitter 1015, a receiver 910, a receiver 1010, or any combination thereof or any component thereof as described herein. In some aspects, the transceiver may be operable to support communication via one or more communication links (e.g., communication link 125, backhaul communication link 120, midhaul communication link 162, fronthaul communication link 168).

[0333] Memory 1225 may include RAM and ROM. Memory 1225 may store computer-readable, computer-executable code 1230 including instructions that, when executed by processor 1235, cause device 1205 to perform various functions described herein. Code 1230 may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, code 1230 may not be directly executable by processor 1235, but may (e.g., when compiled and executed) cause a computer to perform the functions described herein. In some cases, memory 1225 may also include, among other things, a BIOS that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0334] Processor 1235 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA, a microcontroller, a programmable logic device, a discrete gate or transistor logic element, a discrete hardware component, or any combination thereof). In some cases, processor 1235 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated into processor 1235. Processor 1235 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1225) to enable device 1205 to perform various functions (e.g., various functions or tasks of supporting the F1 connection option in an IAB handover scenario). For example, device 1205 or a component of device 1205 may include processor 1235 and memory 1225 coupled to processor 1235, and processor 1235 and memory 1225 are configured to perform various functions described herein. Processor 1235 can be an example of a cloud computing platform (e.g., one or more physical nodes and supporting software (such as an operating system, virtual machine, or container instance)) that can host (e.g., by executing code 1230) functionality for performing the functions of device 1205.

[0335] In some aspects, bus 1240 may support communications of protocol layers (e.g., within a protocol layer) of a protocol stack. In some aspects, bus 1240 may support communications associated with logical channels of a protocol stack (e.g., between protocol layers of a protocol stack), which may include communications performed within components of device 1205, or between different components of device 1205 that may be co-located or located in different locations (e.g., where device 1205 may refer to a system in which one or more of communication manager 1220, transceiver 1210, memory 1225, code 1230, and processor 1235 may be located in one of the different components or divided between the different components).

[0336] In some aspects, the communication manager 1220 can manage aspects of communications with the core network 130 (e.g., via one or more wired or wireless backhaul links). For example, the communication manager 1220 can manage the delivery of data communications for client devices, such as one or more UEs 115. In some aspects, the communication manager 1220 can manage communications with other network entities 105 and can include a controller or scheduler for controlling communications with the UE 115 in coordination with the other network entities 105. In some aspects, the communication manager 1220 can support an X2 interface within an LTE / LTE-A wireless communication network technology to provide communications between network entities 105.

[0337] According to aspects as disclosed herein, the communication manager 1220 may support wireless communication at an IAB node. For example, the communication manager 1220 may be configured to or otherwise support a component for establishing an RRC connection with a first central unit of a first network node. The communication manager 1220 may be configured to or otherwise support a component for receiving from the first network node an indication that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The communication manager 1220 may be configured to or otherwise support a component for communicating with the second network node via an IAB node-to-central unit connection using the RRC connection between the IAB node and the first network node.

[0338] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1220 may support wireless communication at the first network node. For example, the communication manager 1220 may be configured to or otherwise support a component for establishing an RRC connection with an IAB node, wherein the RRC connection is between a first central unit of the first network node and the IAB node. The communication manager 1220 may be configured to or otherwise support a component for sending an indication to the IAB node that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The communication manager 1220 may be configured to or otherwise support a component for relaying (e.g., forwarding) traffic via an IAB node-to-central unit connection between the second network node and the IAB node using the RRC connection between the IAB node and the first network node.

[0339] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1220 may support wireless communication at the first network node. For example, the communication manager 1220 may be configured to or otherwise support a component for receiving an indication of a handover of the IAB node between the second network node and the first network node. The communication manager 1220 may be configured to or otherwise support a component for determining, based on the indication, an address for forwarding traffic from the first network node to the IAB node via the second network node using an IAB node-to-central unit connection between the first central unit of the first network node and the IAB node, wherein the address is different from the IAB node address of the indicating IAB node. The communication manager 1220 may be configured to or otherwise support a component for sending traffic to an address determined by the first network node.

[0340] Additionally or alternatively, according to aspects as disclosed herein, the communication manager 1220 may support wireless communication at a core network node. For example, the communication manager 1220 may be configured to or otherwise support a component for receiving control information from a first network node, the control information indicating that the core network node will forward one or more containers of the IAB node of the IAB node to the central unit connection, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with the second network node. The communication manager 1220 may be configured to or otherwise support a component for sending one or more containers to the second network node based on the second identifier being included in the control information. The communication manager 1220 may be configured to or otherwise support a component for caching control information, a first identifier, a second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward one or more containers. The communication manager 1220 may be configured to or otherwise support a component for sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0341] By including or configuring a communications manager 1220 according to aspects as described herein, the device 1205 can support techniques for improving communications reliability, reducing latency, improving coordination between devices, extending battery life, and improving utilization of processing power.

[0342] In some aspects, the communication manager 1220 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with the transceiver 1210, one or more antennas 1215 (e.g., where applicable), or any combination thereof. Although the communication manager 1220 is illustrated as a separate component, in some aspects, one or more functions described with reference to the communication manager 1220 may be supported or performed by the processor 1235, the memory 1225, the code 1230, the transceiver 1210, or any combination thereof. For example, the code 1230 may include instructions executable by the processor 1235 to cause the device 1205 to perform various aspects of the F1 connection option in the IAB handover scenario as described herein, or the processor 1235 and the memory 1225 may be otherwise configured to perform or support such operations.

[0343] Fig.13 1 is a flowchart illustrating a method 1300 for supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure. The operations of the method 1300 may be implemented by a network entity or a component thereof as described herein. For example, the operations of the method 1300 may be implemented by a network entity or a component thereof as described herein. Figures 1 to 12In some aspects, the network entity may execute an instruction set to control the functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform various aspects of the described functions.

[0344] At 1305, the method may include establishing an RRC connection with a first central unit of a first network node. The operations of 1305 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1305 may be performed as described in reference to Fig.11 The RRC connection component 1125 is used to perform.

[0345] At 1310, the method may include receiving an indication from the first network node that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of the second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The operations of 1310 may be performed according to various aspects as disclosed herein. In some aspects, aspects of the operations of 1310 may be performed as described with reference to Fig.11 The IAB node to central unit connection component 1130 is implemented.

[0346] At 1315, the method may include communicating with the second network node via the IAB node to central unit connection using the RRC connection between the IAB node and the first network node. The operations of 1315 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1315 may be performed as described in reference to Fig.11 The described network node communication component 1135 executes.

[0347] Fig.14 1400 is a flowchart illustrating a method 1400 for supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure. The operations of the method 1400 may be implemented by a network entity or a component thereof as described herein. For example, the operations of the method 1400 may be implemented by a network entity or a component thereof as described herein. Figures 1 to 12 In some aspects, the network entity may execute an instruction set to control the functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform various aspects of the described functions.

[0348] At 1405, the method may include establishing an RRC connection with the IAB node, wherein the RRC connection is between the first central unit of the first network node and the IAB node. The operations of 1405 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1405 may be performed as described in reference to Fig.11 The RRC connection component 1125 is used to perform.

[0349] At 1410, the method may include sending an indication to the IAB node that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via an RRC connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node. The operations of 1410 may be performed according to various aspects as disclosed herein. In some aspects, aspects of the operations of 1410 may be performed as described with reference to Fig.11 The described IAB node to central unit connection component 1130 performs.

[0350] At 1415, the method may include relaying traffic via an IAB node to central unit connection between the second network node and the IAB node using an RRC connection between the IAB node and the first network node. The operations of 1415 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1415 may be performed as described in reference to Fig.11 The described service relay component 1140 executes.

[0351] Fig.15 A flow chart illustrating a method 1500 for supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure is shown. The operations of the method 1500 may be implemented by a network entity or a component thereof as described herein. For example, the operations of the method 1500 may be implemented by a network entity or a component thereof as described herein. Figures 1 to 12 In some aspects, the network entity may execute an instruction set to control the functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform various aspects of the described functions.

[0352] At 1505, the method may include receiving an indication of a handover of the IAB node between the second network node and the first network node. The operations of 1505 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1505 may be performed as described in reference to Fig.11 The handover procedure component 1145 described executes.

[0353] At 1510, the method may include determining, based on the indication, an address for forwarding traffic from the first network node to the IAB node via the second network node using an IAB node-to-central unit connection between the first central unit of the first network node and the IAB node, wherein the address is different from the IAB node address of the indicated IAB node. The operations of 1510 may be performed according to various aspects as disclosed herein. In some aspects, aspects of the operations of 1510 may be performed as described with reference to Fig.11 The business address component 1150 described above performs the above.

[0354] At 1515, the method may include sending the traffic to an address determined by the first network node. The operations of 1515 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1515 may be performed as described in reference to Fig.11 The described network node communication component 1135 executes.

[0355] Fig.16 1 is a flowchart illustrating a method 1600 for supporting an F1 connection option in an IAB handover scenario according to one or more aspects of the present disclosure. The operations of the method 1600 may be implemented by a network entity or a component thereof as described herein. For example, the operations of the method 1600 may be implemented by a network entity or a component thereof as described herein. Figures 1 to 12 In some aspects, the network entity may execute an instruction set to control the functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform various aspects of the described functions.

[0356] At 1605, the method may include receiving control information from a first network node, the control information instructing the core network node to forward one or more containers of the IAB node of the IAB node to the central unit connection, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with the second network node. The operations of 1605 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1605 may be performed as described in reference Fig.11 The described service relay component 1140 executes.

[0357] At 1610, the method may include sending one or more containers to the second network node based on the second identifier being included in the control information. The operations of 1610 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1610 may be performed as described in reference Fig.11 The described network node communication component 1135 executes.

[0358] At 1615, the method may include caching control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node is to forward one or more containers. The operations of 1615 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1615 may be performed as described in reference Fig.11 The described cache component 1155 performs.

[0359] At 1620, the method may include sending one or more other containers associated with the first identifier to a first network node associated with the third identifier or to a second network node associated with the second identifier. The operations of 1620 may be performed according to various aspects as disclosed herein. In some aspects, various aspects of the operations of 1620 may be performed as described in reference to Fig.11 The network node capability component 1160 is used to execute.

[0360] Fig.17 A flow chart illustrating a method 1700 for supporting the f1 connection option in an IAB handover scenario according to aspects of the present disclosure is shown. The operations of the method 1700 may be implemented by a network entity or a component thereof as described herein. For example, the operations of the method 1700 may be implemented by a network entity or a component thereof as described herein. Figures 1 to 12 The network entity performs. In some examples, the network entity may execute an instruction set to control the functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform various aspects of the described functions.

[0361] At 1705, the method may include participating in establishing a communication path between the IAB node and a central unit of the second network node via the core network node, wherein the communication path is an IAB node to central unit connection. The operations of block 1705 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1705 may be performed as described in reference to Fig.11 The described IAB node to central unit connection component 1130 performs.

[0362] At 1710, the method may include forwarding traffic between the IAB node and the central unit via the core network node using the IAB node to central unit connection. The operations of block 1710 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1710 may be performed as described in reference to Fig.11 The described service relay component 1140 executes.

[0363] The following provides an overview of various aspects of the disclosure:

[0364] Aspect 1: A method for wireless communication at an integrated access and backhaul (IAB) node, the method comprising: establishing a radio resource control connection with a first central unit of a first network node; receiving an indication from the first network node that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and communicating with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node.

[0365] Aspect 2: According to the method of Aspect 1, the method also includes: establishing the IAB node to central unit connection of the second central unit of the second network node via the radio resource control connection between the IAB node and the first network node; and after establishing the IAB node to central unit connection, performing a handover procedure from the first network node to the second network node.

[0366] Aspect 3: According to the method described in any one of Aspects 1 to 2, the method further includes: performing a handover procedure from the second network node to the first network node; and after the handover procedure, establishing the IAB node-to-central unit connection with the second central unit of the second network node via the radio resource control connection between the IAB node and the first network node.

[0367] Aspect 4: A method according to any one of Aspects 1 to 3, wherein receiving the indication further comprises: before establishing the radio resource control connection with the first central unit of the first network node, receiving a handover command indicating that the IAB node will establish the radio resource control connection with the first central unit of the first network node, wherein the first network node is a target node of the handover and the second network node is a source node of the handover, and wherein the handover command is the indication.

[0368] Aspect 5: A method according to any one of Aspects 1 to 4, wherein receiving the indication further comprises: receiving a configuration message instructing the IAB node to communicate services via the IAB node-to-central unit connection with the second central unit of the second network node using the radio resource control connection between the IAB node and the first network node, wherein the configuration message is the indication.

[0369] Aspect 6: A method according to Aspect 5, wherein the configuration message includes an Internet Protocol address configuration; and the IAB node selects an Internet Protocol address based on the Internet Protocol address configuration, and uses the Internet Protocol address to communicate via the IAB node to central unit connection with the second central unit of the second network node.

[0370] Aspect 7: The method according to any one of Aspects 1 to 6, wherein communicating via the IAB node to central unit connection further comprises: communicating a service via the IAB node to central unit connection, wherein the service is included in a non-access stratum container corresponding to the radio resource control connection.

[0371] Aspect 8: A method according to any one of Aspects 1 to 7, wherein communicating via the IAB node to the central unit connection also includes: conveying services via the IAB node to the central unit connection, wherein the services include F1-application protocol messages, flow control transmission protocol messages, or Internet protocol packets.

[0372] Aspect 9: The method according to aspect 8, wherein communicating via the IAB node to central unit connection further comprises: communicating the traffic to establish or re-establish the IAB node to central unit connection with the second central unit of the second network node.

[0373] Aspect 10: A method according to any one of Aspects 1 to 9, wherein communicating via the IAB node to central unit connection further comprises: sending an F1-C protocol data unit for the second network node to the first network node using the radio resource control connection, wherein the F1-C protocol data unit is encapsulated in a protocol data unit corresponding to the radio resource control connection.

[0374] Aspect 11: A method according to any one of Aspects 1 to 10, wherein communicating via the IAB node to central unit connection also includes: receiving an F1-C protocol data unit from the second network node from the first network node using the radio resource control connection; and decapsulating the F1-C protocol data unit from the protocol data unit corresponding to the radio resource control connection.

[0375] Aspect 12: The method according to any one of aspects 1 to 11, wherein the communication via the IAB node to central unit connection using the radio resource control connection includes an identifier associated with the second network node.

[0376] Aspect 13: The method according to any one of aspects 1 to 12, wherein the first network node is a first base station or a first IAB donor node, or the second network node is a second base station or a second IAB donor node.

[0377] Aspect 14: A method for wireless communication at a first network node, the method comprising: establishing a radio resource control connection with an integrated access and backhaul (IAB) node, wherein the radio resource control connection is between a first central unit of the first network node and the IAB node; sending an indication to the IAB node that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and relaying traffic via the IAB node-to-central unit connection between the second network node and the IAB node using the radio resource control connection between the IAB node and the first network node.

[0378] Aspect 15: According to the method of Aspect 14, the method also includes: after establishing the IAB node to the central unit connection, executing a handover procedure to hand over the IAB node from the first network node to the second network node, wherein the first network node is the source node of the handover and the second network node is the target node of the handover procedure.

[0379] Aspect 16: According to the method described in any one of Aspects 14 to 15, the method further includes: before establishing the IAB node to the central unit connection, executing a handover procedure to hand over the IAB node from the second network node to the first network node, wherein the first network node is the target node of the handover and the second network node is the source node of the handover procedure.

[0380] Aspect 17: According to the method according to any one of aspects 14 to 16, the method further includes: preparing to hand over the IAB node from the second network node to the first network node, or preparing to hand over the IAB node from the first network node to the second network node.

[0381] Aspect 18: According to the method according to Aspect 17, the method also includes: determining a first identifier of the second network node and a second identifier of a core network node associated with the IAB node based on handover preparation, wherein the service is relayed via the core network node through the IAB node to the central unit connection based on the first identifier or the second identifier.

[0382] Aspect 19: The method according to any one of aspects 17 to 18, wherein in order to prepare for the handover, the first node is configured to prepare for the handover via a base station interface or a core network node interface.

[0383] Aspect 20: A method according to any one of Aspects 14 to 19, wherein sending the indication further comprises: sending a handover command, the handover command instructing the IAB node to establish the radio resource control connection with the first central unit of the first network node, wherein the first network node is the target node of the handover and the second network node is the source node of the handover, and wherein the handover command is the indication.

[0384] Aspect 21: A method according to any one of Aspects 14 to 20, wherein sending the indication further comprises: sending a configuration message instructing the IAB node to communicate services via the IAB node to central unit connection with the second central unit of the second network node using the radio resource control connection between the IAB node and the first network node, wherein the configuration message is the indication.

[0385] Aspect 22: The method according to aspect 21, wherein the configuration message includes an Internet Protocol address configuration, the Internet Protocol address configuration being used to select an Internet Protocol address for communication via the IAB node-to-central unit connection with the second central unit of the second network node.

[0386] Aspect 23: According to the method described in any one of Aspects 14 to 22, the method further includes: receiving a request from the second network node, the IAB node or the core network node to relay the service via the IAB node to the central unit connection; and sending a positive confirmation in response to the request, wherein the first network node relays the service based on sending the positive confirmation.

[0387] Aspect 24: According to the method according to any one of Aspects 14 to 23, the method further comprises: sending a message indicating that the service is interrupted to the second network node or the core network node through which the service is relayed.

[0388] Aspect 25: The method according to aspect 24, wherein the message includes an indication to release an identifier associated with the IAB node.

[0389] Aspect 26: According to the method described in any one of Aspects 14 to 25, the method further includes: receiving a message indicating the ability of the core network node to relay the service via the IAB node to the central unit connection, wherein the service is relayed via the core network node based on the ability of the core network node.

[0390] Aspect 27: According to the method of any one of Aspects 14 to 26, the method also includes: communicating with the second network node an Internet Protocol address configuration for the connection of the IAB node to the central unit, or communicating a request for the Internet Protocol address configuration for the connection of the IAB node to the central unit.

[0391] Aspect 28: The method according to any one of aspects 14 to 27, the method further comprising: configuring an Internet Protocol address for the IAB node for use in the IAB node-to-central unit connection with the second central unit of the second network node.

[0392] Aspect 29: The method according to any one of aspects 14 to 28, wherein the service includes a first identifier of the second network node, a second identifier of a core network node associated with the IAB node, or a third identifier of the IAB node.

[0393] Aspect 30: The method according to any one of aspects 14 to 29, wherein the traffic is relayed using a UE-associated message or a non-UE-associated message, and the UE-associated message is associated with the IAB node.

[0394] Aspect 31: The method according to any one of aspects 14 to 30, wherein the service is relayed via a base station interface or a core network node interface with the second network node.

[0395] Aspect 32: The method according to any one of aspects 14 to 31, wherein the service is included in a non-access stratum container corresponding to the radio resource control connection.

[0396] Aspect 33: A method according to any one of Aspects 14 to 32, wherein the service comprises an F1-application protocol message, a flow control transmission protocol message or an Internet protocol packet.

[0397] Aspect 34: The method according to any one of aspects 14 to 33, wherein the traffic is related to establishing or re-establishing the IAB node-to-central unit connection with the second central unit of the second network node.

[0398] Aspect 35: The method according to any one of aspects 14 to 34, wherein the first network node is a first base station or a first IAB donor node, or the second network node is a second base station or a second IAB donor node.

[0399] Aspect 36: A method for performing wireless communication at a first network node, the method comprising: receiving an indication of a handover of an integrated access and backhaul (IAB) node between a second network node and the first network node; determining, based on the indication, an address for forwarding a service from the first network node to the IAB node via the second network node using an IAB node-to-central unit connection between a first central unit of the first network node and the IAB node, wherein the address is different from the IAB node address indicating the IAB node; and sending the service to the address determined by the first network node.

[0400] Aspect 37: According to the method of Aspect 36, the method also includes: before establishing the IAB node to the central unit connection, executing a handover procedure to hand over the IAB node from the first network node to the second network node, wherein the first network node is the source node of the handover and the second network node is the target node of the handover procedure.

[0401] Aspect 38: According to the method described in any one of Aspects 36 to 37, the method further includes: after establishing the IAB node to the central unit connection, executing a handover procedure to hand over the IAB node from the second network node to the first network node, wherein the first network node is the target node of the handover and the second network node is the source node of the handover procedure.

[0402] Aspect 39: According to the method according to any one of aspects 36 to 38, the method further includes: preparing to hand over the IAB node from the second network node to the first network node, or preparing to hand over the IAB node from the first network node to the second network node.

[0403] Aspect 40: According to the method described in Aspect 39, the method also includes: determining a first identifier of the first network node and a second identifier of a core network node associated with the IAB node based on handover preparation, wherein the service is sent via the core network node based on the first identifier or the second identifier.

[0404] Aspect 41: A method according to any one of aspects 39 to 40, wherein the first network node prepares for handover via a base station interface with the second network node, and the first network node determines to send the service via the second network node based on the address of the second network node.

[0405] Aspect 42: The method according to any one of aspects 39 to 41, wherein the first network node prepares for handover via a core network node interface, and the first network node determines to send the service via the core network node based on the address of the core network node.

[0406] Aspect 43: According to the method described in any one of Aspects 36 to 42, the method further includes: sending a request to the second network node or the core network node for the second network node to relay the service via the IAB node to the central unit connection; and receiving a positive confirmation in response to the request, wherein the service is sent based on the positive confirmation, and the first network node receives the service based on the positive confirmation.

[0407] Aspect 44: According to the method according to any one of Aspects 36 to 43, the method further comprises: sending a message indicating that the service is interrupted to the second network node or the core management network node via which the service is sent.

[0408] Aspect 45: The method according to aspect 44, wherein the message includes an indication to release an identifier associated with the IAB node.

[0409] Aspect 46: According to the method described in any one of Aspects 36 to 45, the method further includes: receiving a message indicating the ability of the core network node to relay the service via the IAB node to the central unit connection, wherein the service is sent via the core network node based on the ability of the core network node.

[0410] Aspect 47: The method according to any one of Aspects 36 to 46, the method further comprising: communicating with the second network node an Internet Protocol address configuration for the connection of the IAB node to the central unit, or a request for the Internet Protocol address configuration for the connection of the IAB node to the central unit.

[0411] Aspect 48: The method according to any one of Aspects 36 to 47, further comprising: configuring an Internet Protocol address for the IAB node for use in the IAB node-to-central unit connection between the first central unit of the first network node and the IAB node.

[0412] Aspect 49: According to the method according to any one of Aspects 36 to 48, the method further comprises: receiving a protocol data unit of the service from the address.

[0413] Aspect 50: The method according to any one of aspects 36 to 49, wherein the service comprises a first identifier of the first network node, a second identifier of a core network node associated with the IAB node, or a third identifier of the IAB node.

[0414] Aspect 51: The method according to any one of aspects 36 to 50, wherein the service is sent using a UE associated message or a non-UE associated message, and the UE associated message is associated with the IAB node.

[0415] Aspect 52: A method according to any one of Aspects 36 to 51, wherein the service comprises an F1-application protocol message, a flow control transmission protocol message or an Internet protocol packet.

[0416] Aspect 53: The method according to any one of aspects 36 to 52, wherein the traffic is sent to establish or re-establish the IAB node-to-central unit connection with the first central unit of the first network node.

[0417] Aspect 54: The method according to any one of aspects 36 to 53, wherein the first network node is a first base station or a first IAB donor node, or the second network node is a second base station or a second IAB donor node.

[0418] Aspect 55: A method for performing wireless communication at a core network node, the method comprising: receiving control information from a first network node, the control information indicating that the core network node will forward one or more containers connected to an integrated access and backhaul (IAB) node of an IAB node to a central unit, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; sending the one or more containers to the second network node based on the second identifier being included in the control information; caching the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node will forward the one or more containers; and sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0419] Aspect 56: The method according to aspect 55, wherein receiving the control information further comprises: receiving a request to forward the one or more containers to or from the second network node based on the second identifier being included in the control information.

[0420] Aspect 57: According to the method of Aspect 56, the method also includes: sending a confirmation message in response to the request.

[0421] Aspect 58: The method according to aspect 57, wherein sending the one or more containers or the one or more other containers further comprises: sending the one or more containers or the one or more other containers based on the confirmation message.

[0422] Aspect 59: According to the method described in any one of Aspects 55 to 58, the method also includes: sending a message indicating the ability of the core network node to relay services to the first network node or the second network node via the IAB node to the central unit connection, wherein the communication of the control information, the one or more containers, or the one or more other containers is based on the ability of the core network node.

[0423] Aspect 60: According to any one of Aspects 55 to 59, the method also includes: receiving a message indicating the ability of the second network node to relay services via the IAB node to the central unit connection, wherein the control information, the one or more containers, or the one or more other containers are relayed to the second network node based on the ability of the second network node.

[0424] Aspect 61: According to the method described in any one of Aspects 55 to 60, the method also includes: receiving a release message from the first network node or the second network node, the release message instructing the core network node to release the cached information, wherein the release message includes an identifier associated with the one or more containers or the first identifier.

[0425] Aspect 62: The method according to aspect 61, further comprising: relaying the release message to the first network node or the second network node.

[0426] Aspect 63: The method according to any one of aspects 55 to 62, wherein the first network node is a source node of a handover procedure, in which the IAB node is handed over from the first network node to the second network node.

[0427] Aspect 64: The method according to any one of aspects 55 to 63, wherein the second network node is a source node of a handover procedure, in which the IAB node is handed over from the second network node to the first network node.

[0428] Aspect 65: A method according to any one of aspects 55 to 64, wherein the control information, the one or more containers or the one or more other containers are included in a non-access stratum message.

[0429] Aspect 66: A method according to any one of aspects 55 to 65, wherein the first network node corresponds to a network node type, or the second network node corresponds to the network node type, and the network node type is an IAB node type.

[0430] Aspect 67: The method according to any one of aspects 55 to 66, wherein the first identifier associated with the IAB node is indicated by the first network node or the second network node.

[0431] Aspect 68: A method according to any one of Aspects 55 to 67, wherein the control information includes a handover requirement indicator, a request to create a UE context, a handover request confirmation indicator, a response to an indication to create a UE context, a notification of a handover procedure, a notification of receiving a notification of a handover procedure, a confirmation associated with a notification of a handover procedure, or an indication of completion of the release of the UE context.

[0432] Aspect 69: A method according to any one of aspects 55 to 68, wherein the core network node is an access and mobility management function or a mobility management entity.

[0433] Aspect 70: The method according to any one of aspects 55 to 69, wherein the first network node is a first base station or a first IAB donor node, or the second network node is a second base station or a second IAB donor node.

[0434] Aspect 71: The method according to any one of aspects 55 to 70, wherein the first network node or the second network node is a second core network node.

[0435] Aspect 72: An integrated access and backhaul (IAB) node (e.g., an apparatus for wireless communication at an IAB node), the IAB node comprising a memory and at least one processor coupled to the memory, wherein the at least one processor is configured to perform a method according to any one of Aspects 1 to 13.

[0436] Aspect 73: An apparatus for wireless communication at an integrated access and backhaul (IAB) node, the apparatus comprising at least one means for performing a method according to any one of aspects 1 to 13.

[0437] Aspect 74: A non-transitory computer-readable medium having stored thereon code for wireless communication, the code, when executed by an integrated access and backhaul (IAB) node, causes the network node to perform the method according to any one of aspects 1 to 13.

[0438] Aspect 75: A first network node for wireless communication (e.g., an apparatus for wireless communication at a first network node), the first network node comprising a memory and at least one processor, the at least one processor being coupled to the memory, wherein the at least one processor is configured to perform a method according to any one of Aspects 14 to 35.

[0439] Aspect 76: An apparatus for wireless communication at a first network node, the apparatus comprising at least one means for performing a method according to any one of aspects 14 to 35.

[0440] Aspect 77: A non-transitory computer readable medium having stored thereon code for wireless communication, the code, when executed by a first network node, causes the network node to perform a method according to any one of aspects 14 to 35.

[0441] Aspect 78: A first network node for wireless communication (e.g., an apparatus for wireless communication at a first network node), the first network node comprising a memory and at least one processor, the at least one processor being coupled to the memory, wherein the at least one processor is configured to perform a method according to any one of Aspects 36 to 54.

[0442] Aspect 79: An apparatus for wireless communication at a first network node, the apparatus comprising at least one means for performing a method according to any one of aspects 36 to 54.

[0443] Aspect 80: A non-transitory computer readable medium having stored thereon code for wireless communication, the code, when executed by a first network node, causes the network node to perform a method according to any one of aspects 36 to 54.

[0444] Aspect 81: A core network node for wireless communications (e.g., a device for performing wireless communications at a core network node), the core network node comprising a memory and at least one processor, the at least one processor being coupled to the memory, wherein the at least one processor is configured to perform a method according to any one of Aspects 55 to 71.

[0445] Aspect 82: An apparatus for wireless communication at a core network node, the apparatus comprising at least one means for performing a method according to any one of aspects 55 to 71.

[0446] Aspect 83: A non-transitory computer readable medium having stored thereon code for wireless communication, the code, when executed by a core network node, causes the network node to perform a method according to any one of aspects 55 to 71.

[0447] Aspect 84: A method for wireless communication performed by a first network node, the method comprising: participating in establishing a communication path between an integrated access and backhaul (IAB) node and a central unit of a second network node via a core network node, wherein the communication path is an IAB node to central unit connection; and using the IAB node to central unit connection to forward traffic between the IAB node and the central unit via the core network node.

[0448] Aspect 85: A method according to Aspect 84, wherein the second network node is different from the first network node, and the central unit of the second network node is a second central unit, and wherein participating in establishing the communication path also includes: establishing a radio resource control connection with the IAB node, wherein the radio resource control connection is located between the first central unit of the first network node and the IAB node; and sending first control information to the IAB node, the first control information indicating that the IAB node will establish the IAB node to central unit connection with the second central unit of the second network node via the radio resource control connection between the IAB node and the first network node, wherein the first control information is associated with the handover of the IAB node between the first network node and the second network node.

[0449] Aspect 86: According to the method of Aspect 85, the method also includes: after establishing the connection between the IAB node and the central unit, executing a first handover procedure to hand over the IAB node from the first network node to the second network node, or before establishing the connection between the IAB node and the central unit, executing a second handover procedure to hand over the IAB node from the second network node to the first network node.

[0450] Aspect 87: According to the method described in any one of Aspects 85 to 86, the method further includes: preparing to hand over the IAB node from the second network node to the first network node, or preparing to hand over the IAB node from the first network node to the second network node; determining a first identifier of the second network node and a second identifier of the core network node based on the handover preparation; and forwarding the service via the core network node through the IAB node to the central unit connection based on the first identifier or the second identifier.

[0451] Aspect 88: A method according to any one of Aspects 85 to 87, wherein sending the first control information also includes: sending a configuration message instructing the IAB node to use the radio resource control connection between the IAB node and the first network node to communicate services via the IAB node to central unit connection with the second central unit of the second network node, wherein the configuration message is the first control information and includes an Internet Protocol address configuration, the Internet Protocol address configuration is used to select an Internet Protocol address for communication via the IAB node to central unit connection with the second central unit of the second network node; and configuring the Internet Protocol address for the IAB node for use with the IAB node to central unit connection with the second central unit of the second network node.

[0452] Aspect 89: According to the method described in any one of Aspects 85 to 88, the method further includes: receiving a request from the second network node, the IAB node or the core network node to forward the service via the IAB node to the central unit connection; and sending a positive confirmation in response to the request, wherein forwarding the service is based on sending the positive confirmation.

[0453] Aspect 90: According to the method described in any one of Aspects 85 to 89, the method further includes: sending a message indicating that the service is interrupted to the second network node or the core network node via which the service is forwarded, the message including an indication of releasing the identifier associated with the IAB node.

[0454] Aspect 91: According to the method according to any one of Aspects 85 to 90, the method also includes: communicating with the second network node an Internet Protocol address configuration for the connection of the IAB node to the central unit, or communicating a request for the Internet Protocol address configuration for the connection of the IAB node to the central unit.

[0455] Aspect 92: A method according to Aspect 84, wherein the second network node is the first network node, and wherein participating in establishing the communication path further includes: receiving an indication of a handover of the IAB node between the first network node and a third network node; and determining, based on the indication, an address for forwarding the service from the first network node to the IAB node via the third network node using the IAB node to the central unit connection, wherein the address is different from the IAB node address indicating the IAB node.

[0456] Aspect 93: According to the method of Aspect 92, the method also includes: before establishing the connection between the IAB node and the central unit, executing a first handover procedure to hand over the IAB node from the first network node to the third network node, or after establishing the connection between the IAB node and the central unit, executing a second handover procedure to hand over the IAB node from the third network node to the first network node.

[0457] Aspect 94: According to the method described in any one of Aspects 92 to 93, the method also includes: preparing to hand over the IAB node from the third network node to the first network node, or preparing to hand over the IAB node from the first network node to the third network node; determining a first identifier of the first network node and a second identifier of the core network node based on the handover preparation; and forwarding the service via the core network node based on the first identifier or the second identifier.

[0458] Aspect 95: The method according to aspect 94, wherein preparing for handover further comprises: preparing for handover via a network node interface with the third network node; and determining to forward the traffic via the third network node based on the second address of the third network node.

[0459] Aspect 96: A method according to any one of Aspects 94 to 95, wherein preparing for handover further comprises: preparing for handover via a core network node interface; and determining to forward the service via the core network node based on the second address of the core network node.

[0460] Aspect 97: According to the method described in any one of Aspects 92 to 96, the method further includes: sending a request to the third network node or the core network node for the third network node to forward the service via the IAB node to the central unit connection; receiving a positive confirmation in response to the request; forwarding the service based on the positive confirmation; and receiving the service based on the positive confirmation.

[0461] Aspect 98: According to the method described in any one of Aspects 92 to 97, the method further includes: sending a message indicating that the service is interrupted to the third network node or the core network node via which the service is forwarded, the message including a second indication of releasing the identifier associated with the IAB node.

[0462] Aspect 99: According to the method described in any one of Aspects 92 to 98, the method further includes: communicating with the third network node an Internet Protocol address configuration for the connection of the IAB node to the central unit, or communicating a request for the Internet Protocol address configuration for the connection of the IAB node to the central unit; and configuring an Internet Protocol address for the IAB node for use in the connection of the IAB node to the central unit.

[0463] Aspect 100: According to any one of aspects 92 to 99, the method further comprises: receiving a protocol data unit of the service from the address.

[0464] Aspect 101: According to the method described in any one of Aspects 84 to 100, the method further includes: receiving a message indicating the ability of the core network node to relay services via the IAB node to the central unit connection; and relaying the services via the core network node based on the ability of the core network node.

[0465] Aspect 102: A method according to any one of Aspects 84 to 101, wherein the service includes a first identifier of the first network node, a second identifier of the second network node, a third identifier of a core network node associated with the IAB node, or a fourth identifier of the IAB node.

[0466] Aspect 103: A method according to any one of aspects 84 to 102, wherein forwarding the service further comprises: forwarding the service using a UE-associated message or a non-UE-associated message, wherein the UE-associated message is associated with the IAB node.

[0467] Aspect 104: A method according to any one of Aspects 84 to 103, wherein the service includes an F1 application protocol message, a flow control transmission protocol message or an Internet Protocol packet, and the method further includes: establishing or re-establishing the IAB node to central unit connection with the central unit of the second network node.

[0468] Aspect 105: A method for wireless communication by a core network node, the method comprising: receiving control information from a first network node, the control information indicating that the core network node will forward one or more containers connected to an integrated access and backhaul (IAB) node of an IAB node to a central unit, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; sending the one or more containers to the second network node based on the second identifier being included in the control information; caching the control information, the first identifier, the second identifier and a third identifier associated with the first network node, the control information indicating that the core network node will forward the one or more containers; and sending one or more other containers associated with the first identifier to the first network node associated with the third identifier or to the second network node associated with the second identifier.

[0469] Aspect 106: The method according to aspect 105, wherein receiving the control information further comprises: receiving a request to forward the one or more containers to or from the second network node based on the second identifier being included in the control information.

[0470] Aspect 107: According to the method described in any one of Aspects 105 to 106, the method also includes: sending a message indicating the ability of the core network node to relay services to the first network node or the second network node via the IAB node to the central unit connection, wherein the communication of the control information, the one or more containers, or the one or more other containers is based on the ability of the core network node.

[0471] Aspect 108: According to the method described in any one of Aspects 105 to 107, the method further includes: receiving a message indicating the ability of the second network node to relay services via the IAB node to the central unit connection; and relaying the control information, the one or more containers, or the one or more other containers to the second network node based on the ability of the second network node.

[0472] Aspect 109: According to the method described in any one of Aspects 105 to 108, the method also includes: receiving a release message from the first network node or the second network node, the release message instructing the core network node to release the cached information, wherein the release message includes an identifier associated with the one or more containers or the first identifier; and relaying the release message to the first network node or the second network node.

[0473] Aspect 110: A method according to any one of Aspects 105 to 109, wherein the first network node is the source node of a first handover procedure, in which the IAB node is handed over from the first network node to the second network node, or the second network node is the source node of a second handover procedure, in which the IAB node is handed over from the second network node to the first network node.

[0474] Aspect 111: The method according to any one of aspects 105 to 110, wherein the control information, the one or more containers or the one or more other containers are included in a non-access stratum message.

[0475] Aspect 112: A method for wireless communication by an integrated access and backhaul (IAB) node, the method comprising: establishing a radio resource control connection with a first central unit of a first network node; receiving an indication from the first network node that the IAB node will establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; and communicating with the second network node via the IAB node-to-central unit connection using the radio resource control connection between the IAB node and the first network node.

[0476] Aspect 113: A first network node for wireless communication (e.g., an apparatus for wireless communication performed by the first network node), the first network node comprising a memory and at least one processor, the at least one processor coupled to the memory, wherein the first network node is configured to perform a method according to any one of Aspects 84 to 104.

[0477] Aspect 114: An apparatus for wireless communication performed by a first network node, the apparatus comprising at least one means for performing the method according to any one of aspects 84 to 104.

[0478] Aspect 115: A non-transitory computer-readable medium storing code for wireless communication performed by a first network node, the code comprising instructions executable by a processor to perform the method according to any one of aspects 84 to 104.

[0479] Aspect 116: A core network node for wireless communications (e.g., an apparatus for wireless communications by a core network node), the first network node comprising a memory and at least one processor, the at least one processor coupled to the memory, wherein the core network node is configured to perform a method according to any one of Aspects 105 to 111.

[0480] Aspect 117: An apparatus for wireless communication performed by a core network node, the apparatus comprising at least one means for performing a method according to any one of aspects 105 to 111.

[0481] Aspect 118: A non-transitory computer-readable medium storing code for wireless communication performed by a core network node, the code comprising instructions executable by a processor to perform the method according to any one of aspects 105 to 111.

[0482] Aspect 119: An integrated access and backhaul (IAB) node for wireless communication (e.g., an apparatus for wireless communication performed by an integrated access and backhaul (IAB) node), the integrated access and backhaul (IAB) node comprising a memory and at least one processor, the at least one processor being coupled to the memory, wherein the integrated access and backhaul (IAB) node is configured to perform a method according to any one of Aspects 112 to 112.

[0483] Aspect 120: An apparatus for wireless communication performed by an integrated access and backhaul (IAB) node, the apparatus comprising at least one means for performing the method according to any one of aspects 112 to 112.

[0484] Aspect 121: A non-transitory computer-readable medium storing code for wireless communication performed by an integrated access and backhaul (IAB) node, the code comprising instructions executable by a processor to perform the method according to any one of aspects 112 to 112.

[0485] The methods described herein describe possible implementations, and the operations and steps may be rearranged or otherwise modified, and other implementations are possible. In addition, aspects from two or more methods may be combined.

[0486] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein may also be applicable to networks other than LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may be applicable to various other wireless communication systems, such as Ultra Mobile Broadband (UMB), Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and radio technologies not explicitly mentioned herein.

[0487] The information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the specification may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0488] The various illustrative blocks and components described in conjunction with the disclosure herein may be implemented or performed using a general purpose processor, DSP, ASIC, CPU, FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in an alternative, the processor may be any processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0489] The functions described herein may be implemented using hardware, software executed by a processor, firmware, or any combination thereof. When implemented using software executed by a processor, the functions may be stored as one or more instructions or codes of a computer-readable medium or sent using one or more instructions or codes of a computer-readable medium. Other aspects and specific implementations are within the scope of the present disclosure and claims. For example, due to the nature of software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these items. Features that implement the functions may also be physically located at different locations, including being distributed so that various parts of the functions are implemented at different physical locations.

[0490] Computer-readable medium includes both non-transient computer storage medium and communication medium, and the communication medium includes any medium that promotes the transfer of computer program from one place to another place.Non-transient storage medium can be any available medium that can be accessed by general or special-purpose computer.By way of example and not limitation, non-transient computer-readable medium can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc (CD) ROM or other optical disc storage device, disk storage device or other magnetic storage device, or can be used for carrying or storing desired program code components and any other non-transient medium that can be accessed by general or special-purpose computer or general or special-purpose processor in the form of instruction or data structure.In addition, any connection is appropriately referred to as computer-readable medium.For example, if software is sent from website, server or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technology such as infrared, radio and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL or wireless technology such as infrared, radio and microwave are included in the definition of computer-readable medium. Disks and optical disks used herein include CDs, laser discs, optical discs, digital versatile discs (DVDs), floppy disks, and Blu-ray discs, and magnetic disks can reproduce data magnetically and optical discs can reproduce data optically using lasers. Combinations of the above are also included within the scope of computer-readable media.

[0491] As used herein (including in the claims), "or" used in a list of items (e.g., a list of items preceded by a phrase such as "at least one of" or "one or more of") indicates an inclusive list, so that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Moreover, as used herein, the phrase "based on" should not be interpreted as referring to a closed set of information, one or more conditions, one or more factors, etc. In other words, the phrase "based on A" (where "A" can be information, a condition, a factor, etc.) should be interpreted as "based on at least A" unless specifically stated differently.

[0492] As used herein, the term "or" is an inclusive "or" unless restrictive language is used with respect to the listed alternatives. For example, ...

Claims

1. A first network node for wireless communication, the first network node comprising: Memory; and at least one processor coupled to the memory, wherein the first network node is configured to: participating in establishing a communication path between an integrated access and backhaul (IAB) node and a central unit of a second network node via a core network node, wherein the communication path is an IAB node to central unit connection; and Traffic between the IAB node and the central unit is forwarded via the core network node using the IAB node to central unit connection.

2. The first network node according to claim 1, wherein the second network node is different from the first network node and the central unit of the second network node is a second central unit, and wherein in order to participate in establishing the communication path, the first network node is configured to: establishing a radio resource control connection with the IAB node, wherein the radio resource control connection is between a first central unit of the first network node and the IAB node; and sending first control information to the IAB node, the first control information indicating that the IAB node is to establish the IAB node-to-central unit connection with the second central unit of the second network node via the radio resource control connection between the IAB node and the first network node, wherein the first control information is associated with a handover of the IAB node between the first network node and the second network node.

3. The first network node according to claim 2, wherein the first network node is further configured to: Before establishing the IAB node to central unit connection, a first handover procedure is performed to handover the IAB node from the first network node to the second network node, or a second handover procedure is performed to handover the IAB node from the second network node to the first network node.

4. The first network node according to claim 2, wherein the first network node is further configured to: preparing to hand over the IAB node from the second network node to the first network node, or preparing to hand over the IAB node from the first network node to the second network node; and A first identifier of the second network node and a second identifier of the core network node are determined based on handover preparation, wherein, to forward the traffic, the first network node is configured to forward the traffic through the IAB node to central unit connection via the core network node based on the first identifier or the second identifier.

5. The first network node according to claim 2, wherein in order to send the first control information, the first network node is configured to: sending a configuration message instructing the IAB node to communicate traffic via the IAB node-to-central unit connection with the second central unit of the second network node using the radio resource control connection between the IAB node and the first network node, wherein the configuration message is the first control information and includes an Internet Protocol address configuration for selecting an Internet Protocol address for communicating via the IAB node-to-central unit connection with the second central unit of the second network node; and The Internet Protocol address is configured for the IAB node for use in the IAB node-to-central unit connection with the second central unit of the second network node.

6. The first network node according to claim 2, wherein the first network node is further configured to: receiving a request from the second network node, the IAB node or the core network node to forward the traffic via the IAB node to a central unit connection; and A positive acknowledgement is sent in response to the request, wherein the first network node forwards the traffic based on sending the positive acknowledgement.

7. The first network node according to claim 2, wherein the first network node is further configured to: A message indicating that the service is interrupted is sent to the second network node or the core network node via which the service is forwarded, the message including an indication of releasing an identifier associated with the IAB node.

8. The first network node according to claim 2, wherein the first network node is further configured to: An internet protocol address configuration for the IAB node to connect to a central unit, or a request for the internet protocol address configuration for the IAB node to connect to a central unit, is communicated with the second network node.

9. The first network node according to claim 1, wherein the second network node is the first network node, and wherein in order to participate in establishing the communication path, the first network node is configured to: receiving an indication of a handover of the IAB node between the first network node and a third network node; and An address for forwarding the traffic from the first network node to the IAB node via the third network node using the IAB node to central unit connection is determined based on the indication, wherein the address is different from an IAB node address indicating the IAB node.

10. The first network node according to claim 9, wherein the first network node is further configured to: Before establishing the IAB node-to-central unit connection, a first handover procedure is performed to hand over the IAB node from the first network node to the third network node, or after establishing the IAB node-to-central unit connection, a second handover procedure is performed to hand over the IAB node from the third network node to the first network node.

11. The first network node according to claim 9, wherein the first network node is further configured to: preparing to hand over the IAB node from the third network node to the first network node, or preparing to hand over the IAB node from the first network node to the third network node; and A first identifier of the first network node and a second identifier of the core network node are determined based on handover preparation, wherein to forward the traffic, the first network node is configured to forward the traffic via the core network node based on the first identifier or the second identifier.

12. The first network node according to claim 11, wherein in order to prepare for the handover, the first network node is configured to: The handover is prepared via a network node interface with the third network node, and wherein the first network node is configured to determine to forward the traffic via the third network node based on a second address of the third network node.

13. The first network node according to claim 11, wherein in order to prepare for the handover, the first network node is configured to prepare for the handover by: via a core network node interface, and wherein the first network node is configured to determine to forward the traffic via the core network node based on a second address of the core network node.

14. The first network node according to claim 9, wherein the first network node is further configured to: sending a request to the third network node or the core network node for the third network node to forward the service via the IAB node to central unit connection; and Receiving a positive acknowledgement in response to the request, wherein: To forward the traffic, the first network node is configured to forward the traffic based on the positive acknowledgement; and The first network node is further configured to receive the traffic based on the positive acknowledgement.

15. The first network node according to claim 9, wherein the first network node is further configured to: A message indicating that the service is interrupted is sent to the third network node or the core network node via which the service is forwarded, the message including a second indication of releasing an identifier associated with the IAB node.

16. The first network node according to claim 9, wherein the first network node is further configured to: communicating with the third network node an internet protocol address configuration for the IAB node to connect to a central unit, or a request for the internet protocol address configuration for the IAB node to connect to a central unit; and An Internet Protocol address is configured for the IAB node for use in the connection of the IAB node to a central unit.

17. The first network node according to claim 9, wherein the first network node is further configured to: A protocol data unit of the service is received from the address.

18. The first network node according to claim 1, wherein the first network node is further configured to: A message is received indicating a capability of the core network node to relay traffic via the IAB node to central unit connection, wherein to relay the traffic, the first network node is configured to relay the traffic via the core network node based on the capability of the core network node.

19. The first network node of claim 1, wherein the service comprises a first identifier of the first network node, a second identifier of the second network node, a third identifier of the core network node associated with the IAB node, or a fourth identifier of the IAB node.

20. The first network node according to claim 1, wherein in order to forward the traffic, the first network node is configured to: The service is forwarded using a UE-associated message or a non-UE-associated message, wherein the UE-associated message is associated with the IAB node.

21. The first network node according to claim 1, wherein the traffic comprises an F1-application protocol message, a flow control transmission protocol message or an internet protocol packet, and wherein in order to forward the traffic, the first network node is configured to: The IAB node-to-central unit connection with the central unit of the second network node is established or re-established.

22. A core network node for wireless communication, the core network node comprising: Memory; and at least one processor coupled to the memory, wherein the core network node is configured to: receiving control information from a first network node, the control information instructing the core network node to forward an integrated access and backhaul (IAB) node of an IAB node to one or more containers connected by a central unit, wherein the control information includes a first identifier associated with the IAB node and a second identifier associated with a second network node; sending the one or more containers to the second network node based on the second identifier being included in the control information; cache the control information, the first identifier, the second identifier, and a third identifier associated with the first network node, the control information indicating that the core network node is to forward the one or more containers; as well as One or more other containers associated with the first identifier are sent to the first network node associated with the third identifier or to the second network node associated with the second identifier.

23. The core network node according to claim 22, wherein in order to receive the control information, the core network node is configured to: A request is received to forward the one or more containers to or from the second network node based on the second identifier being included in the control information.

24. The core network node according to claim 22, wherein the core network node is further configured to: and sending a message indicating an ability of the core network node to relay traffic to the first network node or the second network node via the IAB node to central unit connection, wherein the communication of the control information, the one or more containers, or the one or more other containers is based on the ability of the core network node.

25. The core network node according to claim 22, wherein the core network node is further configured to: receiving a message indicating a capability of the second network node to relay traffic via the IAB node to central unit connection, wherein the core network node is further configured to relay the control information, the one or more containers, or the one or more other containers to the second network node based on the capability of the second network node.

26. The core network node according to claim 22, wherein the core network node is further configured to: receiving a release message from the first network node or the second network node, the release message instructing the core network node to release the cached information, wherein the release message includes an identifier associated with the one or more containers or the first identifier; and The release message is relayed to the first network node or the second network node.

27. The core network node of claim 22, wherein the first network node is a source node of a first handover procedure, in which the IAB node is handed over from the first network node to the second network node, or the second network node is the source node of a second handover procedure, in which the IAB node is handed over from the second network node to the first network node.

28. The core network node of claim 22, wherein the control information, the one or more containers, or the one or more other containers are included in a non-access stratum message.

29. An integrated access and backhaul (IAB) node for wireless communication, the integrated access and backhaul (IAB) node comprising: Memory; and at least one processor coupled to the memory, wherein the IAB node is configured to: establishing a radio resource control connection with a first central unit of a first network node; receiving, from the first network node, an indication that the IAB node is to establish an IAB node-to-central unit connection with a second central unit of a second network node via the radio resource control connection between the IAB node and the first network node, wherein the indication is associated with a handover between the first network node and the second network node; as well as Communicating with the second network node via the IAB node to central unit connection using the radio resource control connection between the IAB node and the first network node.

30. A method of wireless communication performed by a first network node, the method comprising: participating in establishing a communication path between an integrated access and backhaul (IAB) node and a central unit of a second network node via a core network entity, wherein the communication path is an IAB node to central unit connection; and Traffic between the IAB node and the central unit is forwarded via the core network entity using the IAB node to central unit connection.

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