Techniques for inter-gnb migration for distributed units

Abstract

The present disclosure provides techniques for migrating an integrated access and backhaul (IAB) node from a source centralized unit (CU) to a target IAB-donor CU of a base station. Features of the present disclosure achieve such migration by configuring an IAB-distributed unit (IAB-DU) to establish an Fl connection (Fl-C) with the target IAB-donor CU via a source path prior to occurrence of a user equipment (UE) context transfer. To this end, the source IAB-donor CU can initiate Fl-C establishment between the IAB node DU and the target IAB-donor CU. The source IAB-donor CU can do so by acting as or appearing as an IAB node DU proxy for the target IAB-donor CU. At the same time, the source IAB-donor CU can act as or appear as a target IAB-donor CU proxy for the IAB node DU.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 090,052, filed October 9, 2020, entitled “TECHNIQUES FOR INTER-GNBMIGRATION OF DISTRUBTED UNIT,” and U.S. Patent Application No. 17 / 492,296, filed October 1, 2021, entitled “TECHNIQUES FOR INTER-GNBMIGRATION OF DISTRUBTED UNIT,” which have been assigned to the assignee of this application and are hereby expressly incorporated by reference. Technical Field

[0003] This disclosure relates to wireless communication systems, and more particularly to techniques for inter-gNB migration in distributed units. Background Technology

[0004] Wireless communication systems are widely deployed to provide a variety of telecommunications services such as telephone, video, data, messaging, and broadcasting. Typical wireless communication systems employ multiple access technologies that enable communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power). Examples of such multiple access technologies include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, and Single Carrier Frequency Division Multiple Access (SC-FDMA) systems.

[0005] These multiple access technologies have been adopted in various telecommunications standards to provide a common protocol enabling different wireless devices to communicate at the city, national, regional, and even global levels. For example, fifth-generation (5G) wireless communication technology (which may be referred to as New Radio (NR)) is designed to expand and support a diverse range of use cases and applications relative to current mobile network generations. In one aspect, 5G communication technologies can include: enhanced mobile broadband for human-centric use cases of accessing multimedia content, services, and data; ultra-reliable low latency communication (URLLC) with certain specifications regarding latency and reliability; and massive machine-type communication, which allows for a very large number of connected devices and the transmission of relatively small amounts of non-latency-sensitive information. However, with the continued growth in demand for mobile broadband access, further improvements to NR and ultra-NR communication technologies may be expected.

[0006] Overview

[0007] This disclosure provides techniques for migrating Integrated Access and Backhaul (IAB) nodes (particularly IAB Mobile Terminals (IAB-MTs), IAB Distributed Units (IAB-DUs), and / or User Equipment (UEs) connected to IAB nodes) from a source Centralized Unit (CU) to a target IAB donor CU of a base station. Features of this disclosure achieve such migration by configuring the IAB-DU to establish an F1 connection (F1-C) with the target IAB donor CU via the source path prior to a UE context transfer. For this purpose, the source IAB donor CU can initiate the F1-C establishment between the IAB node DU and the target IAB donor CU. The source IAB donor CU can do this by acting as or presenting itself as an IAB node DU proxy for the target IAB donor CU. Simultaneously, the source IAB donor CU can act as or present itself as a target IAB donor CU proxy for the IAB node DU. Thus, in some cases, the source IAB donor CU can present itself both as an IAB node DU proxy (of the target IAB donor CU) and as a target IAB donor CU proxy (of the IAB node DU). By establishing F1-C with the target IAB donor CU via the source path, the IAB node DU can establish a new transport network layer association (TNLA) with the target IAB donor CU for its F1-C signaling.

[0008] In one example, a method for wireless communication is disclosed. The method may include establishing a first signaling connection between a source IAB donor CU and at least one IAB-DU. The method may also include establishing a second signaling connection between the source IAB donor CU and a target IAB donor CU. The method may further include configuring the source IAB donor CU to act as a first proxy for the at least one IAB-DU to transmit state information associated with the at least one IAB-DU to the target IAB donor CU. The method may include receiving state update information from the target IAB donor CU at the IAB donor CU. The method may further include configuring the source IAB donor CU to act as a second proxy for the target IAB donor CU when transmitting the state update information to the at least one IAB-DU.

[0009] In another example, an apparatus for wireless communication. The apparatus may include a memory with instructions and a processor configured to execute these instructions to establish a first signaling connection between a source IAB donor CU and at least one IAB-DU. The processor may also be configured to execute these instructions to establish a second signaling connection between the source IAB donor CU and a target IAB donor CU. The processor may be further configured to execute instructions to configure the source IAB donor CU as a first proxy for the at least one IAB-DU to transmit status information associated with the at least one IAB-DU to the target IAB donor CU. The processor may be further configured to execute these instructions to receive status update information from the target IAB donor CU at the IAB donor CU. The processor may be further configured to execute these instructions to configure the source IAB donor CU as a second proxy for the target IAB donor CU when transmitting the status update information to the at least one IAB-DU.

[0010] In some aspects, a non-transient computer-readable medium storing instructions that, when executed by a processor, cause the processor to perform the step of establishing a first signaling connection between a source IAB donor CU and at least one IAB-DU. The processor may further perform the step of establishing a second signaling connection between the source IAB donor CU and a target IAB donor CU. The processor may further perform the step of configuring the source IAB donor CU to act as a first proxy for the at least one IAB-DU to transmit status information associated with the at least one IAB-DU to the target IAB donor CU. The processor may further perform the step of receiving status update information from the target IAB donor CU at the IAB donor CU. The processor may further perform the step of configuring the source IAB donor CU to act as a second proxy for the target IAB donor CU when transmitting the status update information to the at least one IAB-DU.

[0011] In some aspects, another apparatus for wireless communication is disclosed. This apparatus may include means for establishing a first signaling connection between a source IAB donor CU and at least one IAB-DU. The apparatus may further include means for establishing a second signaling connection between the source IAB donor CU and a target IAB donor CU. The apparatus may further include means for configuring the source IAB donor CU to act as a first proxy for the at least one IAB-DU to transmit status information associated with the at least one IAB-DU to the target IAB donor CU. The apparatus may include means for receiving status update information from the target IAB donor CU at the IAB donor CU. The apparatus may further include means for configuring the source IAB donor CU to act as a second proxy for the target IAB donor CU when transmitting the status update information to the at least one IAB-DU.

[0012] To achieve the foregoing and related objectives, these one or more aspects include the features fully described below and specifically pointed out in the claims. Certain illustrative features of these one or more aspects are set forth in detail in the following description and drawings. However, these features merely indicate a few of the various ways in which the principles of these various aspects may be employed, and this description is intended to cover all such aspects and their equivalents. Brief description of the attached diagram

[0014] The disclosed aspects will now be described in conjunction with the accompanying drawings, which are provided for illustrative purposes and not for limiting the scope of the disclosure, wherein similar reference numerals denote similar elements, and wherein:

[0015] Figure 1 These are schematic diagrams illustrating examples of wireless communication systems according to various aspects of this disclosure;

[0016] Figure 2 This is a call flow diagram of an example of an F1 connection that can be established between an IAB donor centralized unit (CU) and an IAB donor distributed unit (DU) and an IAB node DU, according to various aspects of this disclosure.

[0017] Figure 3A This is a schematic diagram of IAB donor topology adaptation based on various aspects of this disclosure;

[0018] Figure 3B This is a schematic diagram of an example IAB-DU migration based on various aspects of this disclosure;

[0019] Figure 4 These are schematic diagrams illustrating example implementations of various components of a base station according to various aspects of this disclosure; and

[0020] Figure 5 This is a flowchart illustrating an example of a wireless communication method implemented by a base station according to various aspects of this disclosure.

[0021] Detailed description

[0022] One aspect of 5G NR communication technology involves the use of high-frequency bands, such as those above 24 GHz, often referred to as millimeter-wave (mmW) bands. These bands enable significant improvements in extremely high data rates and data processing capabilities. However, compared to LTE, mmW bands are susceptible to rapid channel variations and suffer from severe free-space path loss and atmospheric absorption. Furthermore, mmW bands are highly susceptible to obstruction (e.g., penetration by hands, heads, bodies, leaves, and buildings). Particularly at mmW frequencies, even minor environmental changes, such as head turns, hand movements, or passing cars, can alter the channel conditions between the base station (BS) and user equipment (UE), thereby impacting communication performance.

[0023] Current mmW 5G NR systems utilize small wavelengths at higher frequencies (mmW) to create highly directional beams using multiple-input multiple-output (MIMO) antenna arrays. These highly directional beams focus the emitted radio frequency (RF) energy in an attempt to overcome propagation and path loss challenges in both the uplink and downlink. However, the omnidirectional path loss and propagation characteristics of millimeter-wave environments necessitate dense deployments of next-generation node base stations (gNBs) (i.e., base stations in NR technology) to guarantee line-of-sight links at any given time and reduce the probability of outages. In such deployments, equipping each gNB with a wired backhaul link (e.g., fiber optic) may be impractical due to the high costs involved. Therefore, network operators have considered wireless backhaul as a more cost-effective alternative solution for high-density deployment scenarios.

[0024] Facilitating wireless backhaul communication can include utilizing integrated access and backhaul (IAB) nodes (which may include “relay nodes”) that can have both gNB-type and user equipment (UE)-type functionalities. IAB nodes provide flexibility to wireless communication systems, allowing only a subset of gNBs to be equipped with conventional wired backhaul capabilities (e.g., using cables or fiber optics), while the remaining gNBs (or IAB nodes) can have direct or indirect (e.g., via relay nodes) wireless connections to the wired backhaul (e.g., possibly through multi-hops via one or more relay nodes).

[0025] Therefore, an IAB node can include gNB-type functionality, allowing the transmission and reception of signals to and from child nodes (e.g., a UE or another IAB node) via an access link. Additionally, an IAB node can also include UE-type functionality, allowing the transmission and reception of signals to and from a parent node (e.g., a gNB or another IAB node) via a backhaul link. By utilizing IAB nodes, shared architecture, waveforms, and procedures can be shared for access and backhaul links, thereby reducing system complexity. For example, IAB nodes can share the same radio resources (e.g., via TDM or FDM) between access and backhaul links.

[0026] In an IAB network architecture, one or more base stations may include centralized units (CUs) and distributed units (DUs), and may be referred to as donor base stations (e.g., IAB donors). One or more DUs associated with a donor base station may be partially controlled by one or more CUs associated with that donor base station. Base station CUs may be components of a database, data center, core network, or network cloud. Network nodes associated with a radio access network (RAT) may communicate with the donor base station CU via a backhaul link (e.g., wired backhaul or wireless backhaul). One or more donor base stations (e.g., IAB donors) may also communicate with one or more additional base stations (e.g., IAB nodes or relay nodes) and user equipment (UEs). IAB nodes may support MT functionality controlled and scheduled by the IAB donor and / or parent IAB node relative to IAB nodes supported by a mobile terminal (MT), and DU operability relative to additional entities (e.g., IAB nodes, UEs, etc.) within the access network's relay chain or configuration (e.g., downstream). For example, an IAB network architecture may include a chain of connected radio devices (e.g., starting with a donor base station and ending with a user equipment (UE), with any number of IAB relay nodes in between) via link resources that support NR access and backhaul capabilities (e.g., wired backhaul or wireless backhaul).

[0027] In some respects, a relay node may refer to an intermediary node in a relay (e.g., an IAB relay) chain. For example, a relay node may relay communication between a parent network device (e.g., an IAB donor, or an IAB node located upstream or higher in the relay chain) and a child network device (e.g., an IAB node located downstream or lower in the relay chain). In some cases, a relay node may refer to the DU or Access Node Function (AN-F) of an intermediary IAB node. A child node may refer to an IAB node (e.g., the CU / MT of an IAB node), or a child node may refer to a UE that is a child node of another IAB node (e.g., a relay node) or an IAB donor (e.g., the DU / ANF of an IAB node or an IAB donor). A parent node communicating with a relay node may refer to an upstream IAB node or an IAB donor (e.g., the DU / ANF of an IAB node or an IAB donor). In some cases, a parent node may be referred to as a control node (e.g., a control node may refer to a parent node or a DU that is in communication with the relay node or other intermediary IAB node's MT).

[0028] Therefore, as mentioned above, the access node or base station can be split into DU and CU. The interface between DU and CU can be referred to as the F1 interface. Specifically, an F1 connection (F1-C) can be established between the IAB donor CU and each of the IAB donor DU and IAB node DU. The F1-AP / SCTP connection can be used to exchange control plane (CP) messages. During the F1 setup procedure, the gNB-DU can send an F1 setup request message to the gNB-CU, which includes a list of cells configured and ready to be activated. Furthermore, the gNB-CU can send an F1 setup response message to the gNB-DU, which may optionally include a list of cells to be activated. Each served cell on the gNB-DU can be identified by an NR Cell Global Identity (NR CGI) and / or an NR Physical Cell ID (NR PCI) pair. In some aspects, F1AP services can be divided into non-UE associated services and UE associated services.

[0029] In an IAB network system, when a mobile terminal (MT) of an IAB node performs a handover from a source CU (e.g., CU-a) to a target CU (e.g., CU-b), the DU associated with that IAB node should also migrate to the target CU (e.g., CU-b), and the IAB node may need to establish an F1-C with the target CU. However, for such a handover to be performed, the IAB-DU may require target path availability to the target CU. Similarly, when an MT switches from a source CU (e.g., CU-a) to a target CU (e.g., CU-b), a UE connected to the IAB node may need to perform a handover to the target CU-b. However, for such a handover to be performed, the delivery of the handover command may require source path availability. Therefore, in the current system, attempting to migrate IAB-MT, IAB-DU, and UE from the source CU to the target IAB donor CU may result in a deadlock scenario.

[0030] This disclosure provides techniques for overcoming such deadlocks. Specifically, in some aspects, the IAB-DU can establish F1-C with the target IAB donor CU via a source path before a UE 104 context transfer occurs. To this end, the source IAB donor CU can initiate the establishment of F1-C between the IAB node DU and the target IAB donor CU. The source IAB donor CU can do this by acting as or presenting itself as an IAB node DU proxy for the target IAB donor CU. Simultaneously, the source IAB donor CU can act as or present itself as a target IAB donor CU proxy for the IAB node DU. Thus, in some cases, the source IAB donor CU can present itself both as an IAB node DU proxy (of the target IAB donor CU) and as a target IAB donor CU proxy (of the IAB node DU). By establishing F1-C with the target IAB donor CU via the source path, the IAB node DU can establish its new transport network layer association (TNLA) with the target IAB donor CU for its F1-C signaling.

[0031] Now refer to Figure 1-5 The various aspects are described in more detail below. Numerous specific details are set forth for illustrative purposes to provide a thorough understanding of one or more aspects. However, it is obvious that such aspects can be practiced without these specific details. Furthermore, as used herein, the term "component" can refer to one of the parts that make up a system, can be hardware, firmware, and / or software stored on a computer-readable medium, and can be divided into other components.

[0032] The following description provides examples and is not intended to limit the scope, applicability, or examples set forth in the claims. Changes may be made to the function and arrangement of the elements discussed without departing from the scope of this disclosure. Various procedures or components may be appropriately omitted, substituted, or added to the examples. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Furthermore, features described with reference to some examples may be combined in other examples.

[0033] Figure 1 This is a diagram illustrating an example of a wireless communication system and access network 100. The wireless communication system (also known as a wireless wide area network (WWAN)) may include base station 102, UE 104, evolved packet core (EPC) 160, and / or 5G core (5GC) 190. Base station 102 may include macrocells (high-power cellular base stations) and / or small cells (low-power cellular base stations). Macrocells may include base stations. Small cells may include femtocells, picocells, and microcells. In one example, base station 102 may also include gNB 180, as further described herein.

[0034] In one example, base station 102 may be an IAB node (IAB donor node or IAB node), which includes a centralized unit (CU), a distributed unit (DU), and / or an IAB mobile terminal (MT). Base station 102 may have a modem 514 and a communication management module 450 (see...). Figure 4 This disclosure discloses a technique for migrating Integrated Access and Backhaul (IAB) nodes (particularly IAB Mobile Terminals (IAB-MTs), IAB Distributed Units (IAB-DUs), and / or User Equipment (UEs) connected to IAB nodes) from a source Centralized Unit (CU) to a target IAB donor CU at a base station. The features of this disclosure achieve this migration by configuring the IAB-DU to establish an F1 connection (F1-C) with the target IAB donor CU via the source path prior to a UE context transfer. For this purpose, the source IAB donor CU can initiate the F1-C establishment between the IAB node DU and the target IAB donor CU. The source IAB donor CU can do this by acting as or presenting itself as an IAB node DU proxy for the target IAB donor CU. Simultaneously, the source IAB donor CU can act as or present itself as a target IAB donor CU proxy for the IAB node DU. Thus, in some cases, the source IAB donor CU can present itself both as an IAB node DU proxy (of the target IAB donor CU) and as a target IAB donor CU proxy (of the IAB node DU). By establishing F1-C with the target IAB donor CU via the source path, the IAB node DU can establish a new transport network layer association (TNLA) with the target IAB donor CU for its F1-C signaling.

[0035] Base station 102 can also be configured for 4G LTE (which may be collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)), and can interface with EPC 160 via backhaul link 132 (e.g., using the S1 interface). Base station 102 configured for 5G NR (which may be collectively referred to as Next Generation RAN (NG-RAN)) can interface with 5GC 190 via backhaul link 184. Among other functions, base station 102 can also perform one or more of the following functions: user data delivery, radio channel cryptography and cryptography decoding, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, distribution of Non-Access Stratum (NAS) messages, NAS node selection, synchronization, Radio Access Network (RAN) sharing, Multimedia Broadcast Multicast Service (MBMS), subscriber and equipment tracking, RAN Information Management (RIM), paging, location, and delivery of alarm messages. Base stations 102 can communicate directly or indirectly (e.g., via EPC 160 or 5GC 190) on backhaul link 134 (e.g., using an X2 interface). Backhaul link 134 can be wired or wireless.

[0036] Base station 102 can wirelessly communicate with one or more UEs 104. Each base station 102 can provide communication coverage for its respective geographical coverage area 110. Overlapping geographical coverage areas 110 may exist. For example, a small cell 102' may have a coverage area 110' that overlaps with the coverage areas 110 of one or more macro base stations 102. A network that includes both small cells and macro cells may be referred to as a heterogeneous network. The heterogeneous network may also include a Home Evolved B Node (eNB) (HeNB), which can provide services to a restricted group (which may be referred to as a Closed Subscriber Group (CSG)). The communication link 120 between base station 102 and UE 104 may include uplink (UL) (also referred to as reverse link) transmission from UE 104 to base station 102 and / or downlink (DL) (also referred to as forward link) transmission from base station 102 to UE 104. The communication link 120 may use multiple-input multiple-output (MIMO) antenna technologies, including spatial multiplexing, beamforming, and / or transmit diversity. These communication links may use one or more carriers. For each carrier allocated in a total of up to Yx MHz (e.g., for x component carriers) used for transmission in the DL and / or UL directions, base station 102 / UE 104 may use a spectrum with a bandwidth of up to Y MHz (e.g., 5, 10, 15, 20, 100, 400 MHz, etc.). These carriers may or may not be adjacent to each other. Carrier allocation may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated to DL compared to UL). Component carriers may include primary component carriers and one or more secondary component carriers. The primary component carrier may be referred to as the primary cell (PCell), and the secondary component carriers may be referred to as secondary cells (SCells).

[0037] In another example, some UEs 104 may communicate with each other using a device-to-device (D2D) communication link 158. The D2D communication link 158 may use DL / UL WWAN spectrum. The D2D communication link 158 may use one or more sidelink channels, such as the Physical Sidelink Broadcast Channel (PSBCH), Physical Sidelink Discovery Channel (PSDCH), Physical Sidelink Shared Channel (PSSCH), and Physical Sidelink Control Channel (PSCCH). D2D communication can be achieved through a wide variety of wireless D2D communication systems, such as, for example, FlashLinQ, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the IEEE 802.11 standard, LTE, or NR.

[0038] The wireless communication system may further include a Wi-Fi access point (AP) 150 communicating with a Wi-Fi station (STA) 152 via a communication link 154 in the 5 GHz unlicensed spectrum. When communicating in the unlicensed spectrum, the STA 152 / AP 150 may perform a clear channel assessment (CCA) before communication to determine whether the channel is available.

[0039] Small cell 102' can operate in licensed and / or unlicensed spectrum. When operating in unlicensed spectrum, small cell 102' can employ NR and use the same 5 GHz unlicensed spectrum as that used by Wi-Fi AP 150. Small cell 102' employing NR in unlicensed spectrum can enhance access network coverage and / or increase access network capacity.

[0040] Whether it's a small cell 102' or a large cell (e.g., a macro base station), base station 102 can include an eNB, a gB node (gNB), or other types of base stations. Some base stations (such as gNB 180) can operate one or more frequency bands within the electromagnetic spectrum. The electromagnetic spectrum is typically subdivided into various classes, bands, channels, etc., based on frequency / wavelength. In 5G NR, two initial operating frequency bands have been identified as the frequency range designations FR1 (410MHz–7.125GHz) and FR2 (24.25GHz–52.6GHz). The frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Although a portion of FR1 is greater than 6GHz, in various documents and articles, FR1 is often (interchangeably) referred to as the "sub-6GHz" band. Similar naming issues sometimes arise with FR2. Although it is different from the Very High Frequency (EHF) band (30 GHz–300 GHz) which is identified by the International Telecommunication Union (ITU) as the “millimeter wave” (mmW) band, FR2 is generally (interchangeably) referred to as the “millimeter wave” band in various documents and articles.

[0041] Considering the above aspects, unless otherwise stated, it should be understood that, as used herein, the term "sub-6GHz" and the like can broadly refer to frequencies less than 6GHz, within FR1, or including intermediate frequency band frequencies. Furthermore, unless otherwise stated, it should be understood that, as used herein, the term "millimeter wave" and the like can broadly refer to frequencies including intermediate frequency band frequencies, within FR2, or within the EHF band. However, communication using the mmW radio frequency band has extremely high path loss and short range. The mmW base station 180 can utilize beamforming 182 with the UE 104 to compensate for the high path loss and short range.

[0042] EPC 160 may include Mobility Management Entity (MME) 162, other MMEs 164, Serving Gateway 166, Multimedia Broadcast Multicast Service (MBMS) Gateway 168, Broadcast Multicast Service Center (BM-SC) 170, and Packet Data Network (PDN) Gateway 172. MME 162 may communicate with Home Subscriber Server (HSS) 174. MME 162 is the control node that handles signaling between UE 104 and EPC 160. Generally, MME 162 provides bearer and connection management. All user Internet Protocol (IP) packets are delivered through Serving Gateway 166, which is itself connected to PDN Gateway 172. PDN Gateway 172 provides UE IP address allocation and other functions. PDN Gateway 172 and BM-SC 170 are connected to IP Service 176. IP Service 176 may include the Internet, intranet, IP Multimedia Subsystem (IMS), PS streaming service, and / or other IP services. The BM-SC 170 provides functionality for MBMS user service provisioning and delivery. The BM-SC 170 can serve as an entry point for content provider MBMS transmissions, authorize and initiate MBMS bearer services within a Public Land Mobile Network (PLMN), and schedule MBMS transmissions. The MBMS gateway 168 can be used to distribute MBMS traffic to base station 102 within a Broadcast-Specific Service Single Frequency Network (MBSFN) area, and can be responsible for session management (start / stop) and collecting eMBMS-related billing information.

[0043] 5GC 190 may include Access and Mobility Management Functions (AMF) 192, other AMFs 193, Session Management Functions (SMF) 194, and User Plane Functions (UPF) 195. AMF 192 may communicate with Unified Data Management (UDM) 196. AMF 192 may be a control node handling signaling between UE 104 and 5GC 190. Generally, AMF 192 provides QoS streaming and session management. User Internet Protocol (IP) packets (e.g., from one or more UEs 104) may be transmitted via UPF 195. UPF 195 provides UE IP address allocation for one or more UEs, as well as other functions. UPF 195 connects to IP service 197. IP service 197 may include the Internet, intranet, IP Multimedia Subsystem (IMS), PS streaming service, and / or other IP services.

[0044] The base station may also be referred to as a gNB, B-node, evolved B-node (eNB), access point, base transceiver station, radio base station, radio transceiver, transceiver function, basic service set (BSS), extended service set (ESS), transmit / receive point (TRP), or any other suitable term. Base station 102 provides UE 104 with access to EPC 160 or 5GC 190. Examples of UE 104 include cellular phones, smartphones, Session Initiation Protocol (SIP) phones, laptop devices, personal digital assistants (PDAs), satellite radios, GPS devices, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablet devices, smart devices, wearable devices, vehicles, electricity meters, gas pumps, large or small kitchen appliances, healthcare devices, implants, sensors / actuators, displays, or any other similar functional devices. Some UE 104 devices may be referred to as IoT devices (e.g., parking timers, oil pumps, ovens, vehicles, heart monitors, etc.). IoT UEs may include Machine Type Communication (MTC) / Enhanced MTC (eMTC, also known as Category (CAT)-M, Cat M1) UEs, NB-IoT (also known as CAT NB1) UEs, and other types of UEs. In this disclosure, eMTC and NB-IoT may refer to technologies that may evolve from or be based on these technologies. For example, eMTC may include FeMTC (Further eMTC), eFeMTC (Further Enhanced eMTC), mMTC (Massively Multi-Level MTC), etc., while NB-IoT may include eNB-IoT (Enhanced NB-IoT), FeNB-IoT (Further Enhanced NB-IoT), etc. UE 104 may also be referred to as a station, mobile station, subscriber station, mobile unit, subscriber unit, radio unit, remote unit, mobile device, radio device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, radio terminal, remote terminal, handheld device, user agent, mobile client, client, or some other suitable term.

[0045] Figure 2This is a timing diagram 200 illustrating an example of an F1 connection that can be established between an IAB donor CU 210 and IAB donor DUs and IAB node DUs. As mentioned above, in an IAB network architecture, one or more base stations may include centralized unit (CU) 210 and distributed unit (DU) 205, and may be referred to as donor base stations (e.g., IAB donors). One or more DUs 205 associated with a donor base station may be partially controlled by one or more CUs 210 associated with that donor base station. Base station CU 210 may be a component of a database, data center, core network, or network cloud. One or more donor base stations (e.g., IAB donors) may communicate with one or more additional base stations (e.g., IAB nodes or relay nodes) and UEs.

[0046] The interface between DU 205 and CU 210 is generally referred to as the F1 interface. Specifically, an F1 connection (F1-C) can be established between the IAB donor CU 210 and each of the IAB donor DU 205 and IAB node DU 205. The F1-AP / SCTP connection can be used to exchange control plane (CP) messages. During the F1 setup procedure, gNB-DU 205 can send an F1 setup request message to gNB-CU 210, which includes a list of cells configured and ready to be activated. Then, gNB-CU 210 can send an F1 setup response message to gNB-DU 205, which may optionally include a list of cells to be activated. Each served cell on gNB-DU 205 can be identified by an NR Cell Global Identity (NR CGI) and / or an NR Physical Cell ID (NR PCI) pair. In some respects, F1AP services can be divided into non-UE-associated services and UE-associated services.

[0047] In some aspects, Flow Control Transport Protocol (SCTP) can be supported as the transport layer for F1-C signaling bearers. In such cases, gNB-DU and gNB-CU can support configurations with a single SCTP association per gNB-DU / gNB-CU pair. Configurations with multiple SCTP endpoints per gNB-DU / gNB-CU pair can also be supported. When configurations with multiple SCTP associations are supported, gNB-CU / gNB-DU can request the dynamic addition / removal of SCTP associations between gNB-DU / gNB-CU pairs. Transport network redundancy can be achieved through SCTP multihoming between two endpoints, one or both of which are assigned multiple IP addresses. SCTP endpoints can also support multihomed remote SCTP endpoints.

[0048] Figure 3AThis is a schematic diagram 300 illustrating topology adaptation between IAB donors. Specifically, in an IAB network system, when a mobile terminal (MT) 320 of IAB node 351 performs a handover from a source CU 305 (e.g., CU-a) to a target CU 310 (e.g., CU-b), a DU 325 associated with IAB node 315 may need to migrate to the target CU 310 (e.g., CU-b). In some examples, a first DU 325-a may be associated with the source CU 305, and a second DU 325-b may be associated with the target CU 310. The second DU 325-b may refer to the migrated DU of IAB node 315, and IAB node 315 may need to establish an F1-C with the target CU. However, in order to perform such a handover, IAB-DU 325 may require the availability of a target path to the target CU 310, which may only be available to DU 325 after IAB-MT 320 has switched to the parent DU 325. Similarly, when MT 320 switches from source CU 305 (e.g., CU-a) to target CU 310 (e.g., CU-b), UE 104 connected to IAB node 315 may also need to perform a handover to target CU-b 310. However, for such a handover to occur, handover command delivery requires the availability of the source path, which may only be available to the UE before IAB-MT 320 switches to parent Dub 325. Therefore, in the current system, attempting to migrate IAB-MT 320, IAB-DU 325, and UE 104 from source CU 305 to target IAB donor CU 310 could result in a deadlock scenario.

[0049] This disclosure provides techniques for overcoming such deadlocks. Specifically, in some aspects, IAB-DU325 can establish an F1-C with the target IAB donor CU 310 before a parent handover occurs at IAB-MT 320, so that handover commands to UE 104 can still be forwarded along the source path. To this end, the source IAB donor CU 305 can initiate the establishment of an F1-C between IAB node DU 325 and the target IAB donor CU 310. The source IAB donor CU 305 can do this by acting as or presenting itself as an IAB node DU proxy of the target IAB donor CU 310. At the same time, the source IAB donor CU 305 can act as or present itself as a target IAB donor CU proxy of IAB node DU 325. Thus, in some cases, the source IAB donor CU 305 can present itself both as an IAB node DU proxy (of the target IAB donor CU) and as a target IAB donor CU proxy (of the IAB node DU). By establishing F1-C with the target IAB donor CU 310 via the source path, the IAB node DU 325 can subsequently establish its new TNLA for F1-C signaling with the target IAB donor CU 310.

[0050] Figure 3B This is a schematic diagram 350 illustrating an example IAB-DU migration technique that migrates an IAB-DU from a source CU 305 to a target CU 310. The IAB donor CU (source CU 305 and / or target CU 310) may be a gNB-CU. In some examples, the first IAB donor CU 305 (or "source CU") may establish a first signaling connection 355 to an IAB node 315 (described as having an IAB-DU 325). In some aspects, the DU 325 may be an IAB donor DU or a gNB-DU. In some aspects, the first signaling connection may be an F1-C or Radio Resource Control (RRC) connection.

[0051] The first IAB donor 305 may subsequently establish a second connection 360 to the second IAB donor CU 310 (or “target CU”). In such an instance, the second connection 360 may be F-1C ​​signaling. Once the first IAB donor CU 305 has established the second signaling connection 360 with the second IAB CU 310, the first IAB donor CU 305 may act as a proxy 365 for the distributed unit of IAB node 315 and forward the status of IAB node DU 325 to the second IAB donor CU 310.

[0052] In some examples, forwarding the status of IAB node DU to the second IAB donor CU may include forwarding the configuration sent by IAB node DU325 to the first IAB donor CU305 and / or forwarding the configuration sent by the first IAB donor CU305 to IAB node DU325. In some aspects, the first IAB donor CU305 may further forward a second status update between IAB node DU325 and the second IAB donor CU310. Forwarding status / status updates to the second IAB donor CU310 may also utilize an F1 setup request message, a gNB-DU configuration update message, or a gNB-CU configuration update acknowledgement message. Furthermore, forwarding status updates to IAB node DU325 may utilize one or more of an F1 setup response message, a gNB-DU configuration update acknowledgement message, or a gNB-CU configuration update message.

[0053] In some respects, the IAB Node DU status information forwarded by the first IAB donor CU 305 to the second IAB donor CU 210 may include one or more of the following: the configuration of the cell served by the IAB Node DU, transport layer information about SCTP connections carrying UE-associated and / or non-UE-associated F1-C signaling, transport layer information about F1-U GTP-U tunnels used to connect to the child nodes of the IAB Node DU, or the context of the child nodes connected to the IAB Node DU, the connection between the IAB-DU and the IAB donor CU, the gNB-CU, the tunnel endpoint identifier between the gNB-DU and the gNB-CU, the flow between the gNB-DU and the gNB-CU, or the identifier associated with the child nodes connected to the IAB Node DU.

[0054] In some examples, the first IAB donor CU 305 may also indicate the same gNB-DU-ID as the gNB-DU-ID of the IAB node DU 325 when establishing the second signaling connection 360. In some examples, the first IAB donor CU 305 may indicate a TNL endpoint for the second IAB donor CU 380 to the IAB-DU 325. CU 305 may achieve this by providing an additional TNL endpoint that will be used by the IAB-DU 325 to establish a new TNLA for the first signaling connection to the IAB-DU. This is possible according to aspects of this disclosure because CU 305 may have multiple TNL endpoints that CU 305 can select from for the first signaling connection. However, since the TNL endpoint newly indicated by CU-a 305 to the IAB-DU is configured as a TNL endpoint of Cub 310, rather than an additional CU-a TNL endpoint for the first signaling connection, aspects of this disclosure allow for the establishment of a direct TNLA between the second CU 310 and the IABDU 325. The additional TNL endpoint 380 configured on the second IAB donor CU 310 may include Internet Protocol (IP) address information about the second IAB donor CU 310. The first IAB donor CU 305 may also use a gNB-CU configuration update message to indicate the TNLA 375 to be added. In some aspects, the gNB-CU configuration update message may be sent using the TNLA 370. In some aspects, the first IAB donor CU 305 may request the IAB node 315 to acknowledge (ACK) the TNLA establishment on the TNLA-b 375 using the IP address of the second IAB donor CU 315.

[0055] In some respects, IAB node DU 325 can establish a second TNLA 375 (e.g., SCTP association) with second IAB donor CU 310 by adding a TNL endpoint 380 to second IAB donor CU 310 based on first IAB donor CU 305. In such an instance, first IAB donor CU 305 can instruct IAB node DU 325 to use the second TNLA 375 for the first signaling connection. After establishing the second TNLA 375, first IAB donor CU can instruct IAB node DU 325 to remove the first TNLA 370 used for the first signaling connection. IAB node DU 325 can then include the gNB-DU ID in the F1-C signaling using the second TNLA 375. IAB node DU 325 can also send a gNB-CU configuration update acknowledgment message or a gNB-DU configuration update message to second IAB donor CU 310 after the second TNLA 375 becomes operational.

[0056] In some respects, the first IAB donor CU 305 may indicate to the IAB node 315 that it is acting as a proxy for the second IAB donor CU 310. The first IAB donor CU 305 may also provide the IAB node 315 with the identifier of the second IAB donor CU 310. In some examples, the first IAB donor CU 305 may request the IAB node DU 325 to include the gNB-DU ID in the F1-C signaling using the new TNLA.

[0057] In some examples, the first IAB donor CU 305 may subsequently indicate to the second IAB donor CU 310 that it is acting as a proxy for the IAB node DU 325. The first IAB donor CU 305 may subsequently transmit the context of the corresponding IAB node MT 320 to the second IAB donor CU 310, or indicate the corresponding IAB node MT 320 to the second IAB donor CU 310. The first IAB donor CU 305 may indicate to the second IAB donor CU 310 that a second TNLA 375 will be established for the IAB node 315 to use for a second signaling connection. To this end, the second IAB donor CU 310 may request the first IAB donor CU 305 to remove the third TNLA used for the second signaling connection after the IAB node establishes the second TNLA 375. Thus, the first IAB donor CU 305 may remove the third TNLA for the second signaling connection after instructing the IAB node 315 to establish the second TNLA 375 and / or after receiving an instruction from the IAB node 315 or the second IAB donor CU 310 that the second TNLA 375 has become operational.

[0058] In some scenarios, the second IAB donor CU 310 may provide a new gNB-CU identifier to the first IAB donor CU 305, which may then send an update to the IAB node 315. This gNB-CU identifier can be a gNB-CU name. Alternatively, it can be a gNB-ID; based on this gNB-ID, the first IAB donor CU reconfigures the cell ID for the cell served by the IAB node DU. The first IAB donor CU 305 may request a new gNB-CU identifier from the second IAB donor CU 310.

[0059] In some examples, the second IAB donor CU 310 may provide a new gNB-CU identifier to the IAB node 315 after the IAB node 315 establishes a TNLA 375 with the second IAB donor CU 310. Additionally or alternatively, the first IAB donor CU 305 may instruct the second IAB donor CU 310 to provide a new gNB-CU identifier to the IAB node after the second TNLA 375 becomes operational. The first IAB donor CU 305 may request the second IAB donor CU 310 to use the old gNB-CU identifier for the second signaling connection.

[0060] Figure 4 Hardware components and sub-components of an apparatus (which may be base station 102) for implementing one or more methods (e.g., method 500) described herein, according to various aspects of this disclosure, are explained. For example, an example implementation of base station 102 may include a wide variety of components, some of which have already been described above, but also components such as one or more processors 412, memory 416, and transceiver 402 communicating via one or more buses 444, which may operate in conjunction with communication management component 4505 to implement the functions described herein in relation to one or more methods (e.g., 500) including this disclosure. In some examples, base station 102 may be an IAB node (IAB donor node or IAB node) that includes a centralized unit (CU), a distributed unit (DU), and / or an IAB mobile terminal (MT).

[0061] Specifically, the communication management component 450 implements techniques for migrating Integrated Access and Backhaul (IAB) nodes (especially IAB Mobile Terminals (IAB-MTs), IAB Distributed Units (IAB-DUs), and / or User Equipment (UEs) connected to IAB nodes) from a source Centralized Unit (CU) to a target IAB donor CU of a base station. The features of this disclosure achieve this migration by configuring the IAB-DU to establish an F1 connection (F1-C) with the target IAB donor CU via the source path prior to a UE context transfer. For this purpose, the source IAB donor CU can initiate the F1-C establishment between the IAB node DU and the target IAB donor CU. The source IAB donor CU can do this by acting as or presenting itself as an IAB node DU proxy for the target IAB donor CU. Simultaneously, the source IAB donor CU can act as or present itself as a target IAB donor CU proxy for the IAB node DU. Therefore, in some cases, the source IAB donor CU can appear as both an IAB node DU proxy (of the target IAB donor CU) and a target IAB donor CU proxy (of the IAB node DU). By establishing F1-C with the target IAB donor CU via the source path, the IAB node DU can establish a new transport network layer association (TNLA) with the target IAB donor CU for its F1-C signaling.

[0062] One or more processors 412, modems 414, memory 416, transceivers 402, RF front-ends 488, and one or more antennas 465 may be configured to support voice and / or data calls (simultaneously or asynchronously) in one or more radio access technologies. In one aspect, the one or more processors 412 may include modems 414 using one or more modem processors. Various functions associated with the communication management component 450 may be included in modems 414 and / or processors 412, and in one aspect may be performed by a single processor, while in other aspects, different functions may be performed by a combination of two or more different processors. For example, in one aspect, the one or more processors 412 may include any one or any combination of: a modem processor, or a baseband processor, or a digital signal processor, or a transmitter processor, or a receiver processor, or a transceiver processor associated with transceiver 402. In other aspects, some features of one or more processors 412 and / or modems 414 associated with the initial access module 450 may be performed by transceiver 402.

[0063] Memory 416 may be configured to store data used herein and / or a local version of application 475, or one or more of communication management component 450 and / or its sub-components executed by at least one processor 412. Memory 416 may include any type of computer-readable medium that can be used by a computer or at least one processor 412, such as random access memory (RAM), read-only memory (ROM), tape, magnetic disk, optical disk, volatile memory, non-volatile memory, and any combination thereof. In one aspect, for example, when base station 102 is operating at least one processor 412 to execute communication management component 450 and / or one or more of its sub-components, memory 416 may be a non-transient computer-readable storage medium storing one or more computer-executable codes defining communication management component 450 and / or one or more of its sub-components and / or associated data.

[0064] Transceiver 402 may include at least one receiver 406 and at least one transmitter 408. Receiver 406 may include hardware, firmware, and / or processor-executable software code for receiving data, the code comprising instructions and stored in memory (e.g., a computer-readable medium). Receiver 406 may be, for example, a radio frequency (RF) receiver. In one aspect, receiver 406 may receive signals transmitted by at least one UE 104. Additionally, receiver 406 may process such received signals and may also obtain measurements of the signals, such as, but not limited to, Ec / Io, SNR, RSRP, RSSI, etc. Transmitter 408 may include hardware, firmware, and / or processor-executable software code for transmitting data, the code comprising instructions and stored in memory (e.g., a computer-readable medium). Suitable examples of transmitter 408 may include, but are not limited to, RF transmitters.

[0065] Furthermore, in one aspect, the transmitting device may include an RF front-end 488, which is communicatively operable with one or more antennas 465 and a transceiver 402 for receiving and transmitting radio transmissions, such as wireless communications transmitted by at least one base station 102 or wireless transmissions transmitted by a UE 104. The RF front-end 488 may be connected to one or more antennas 465 and may include one or more low-noise amplifiers (LNAs) 490, one or more switches 492, one or more power amplifiers (PAs) 498, and one or more filters 496 for transmitting and receiving RF signals.

[0066] On one hand, the LNA 490 can amplify the received signal to a desired output level. On another hand, each LNA 490 can have specified minimum and maximum gain values. On yet another hand, the RF front end 488 can use one or more switches 492 to select a particular LNA 490 and its specified gain value based on the desired gain value for a particular application.

[0067] Furthermore, for example, one or more PAs 498 may be used by the RF front end 488 to amplify signals to obtain an RF output with a desired output power level. In one aspect, each PA 498 may have specified minimum and maximum gain values. In another aspect, the RF front end 488 may use one or more switches 492 to select a particular PA 498 and its specified gain value based on the desired gain value for a particular application.

[0068] Furthermore, for example, one or more filters 496 may be used by the RF front end 488 to filter the received signal to obtain the input RF signal. Similarly, in one aspect, for example, a corresponding filter 496 may be used to filter the output from a corresponding PA 498 to produce an output signal for transmission. In one aspect, each filter 496 may be connected to a specific LNA 490 and / or PA 498. In one aspect, the RF front end 488 may use one or more switches 492 to select the transmit or receive path using a specified filter 496, LNA 490, and / or PA 498 based on a configuration as specified by the transceiver 402 and / or processor 412.

[0069] Thus, transceiver 402 can be configured to transmit and receive wireless signals via RF front end 488 through one or more antennas 465. In one aspect, transceiver 402 can be tuned to operate at a specified frequency so that the transmitting device can, for example, communicate with one or more UEs 104. In another aspect, for example, modem 414 can configure transceiver 402 to operate at a specified frequency and power level based on the configuration of the transmitting device and the communication protocol used by modem 414.

[0070] In one aspect, modem 414 may be a multi-band, multi-mode modem capable of processing digital data and communicating with transceiver 402 to enable the use of transceiver 402 to transmit and receive digital data. In another aspect, modem 414 may be multi-band and configured to support multiple frequency bands for a specific communication protocol. In another aspect, modem 414 may be multi-mode and configured to support multiple operating networks and communication protocols. In one aspect, modem 414 may control one or more components of the transmitting device (e.g., RF front-end 488, transceiver 402) to enable signal transmission and / or reception with the network based on a specified modem configuration. In one aspect, the modem configuration may be based on the mode and frequency band used by modem 414. In another aspect, the modem configuration may be based on UE configuration information associated with the transmitting device, such as information provided by the network during cell selection and / or cell reselection.

[0071] Reference Figure 5Example methods 500 for wireless communication according to various aspects of this disclosure can be found by reference. Figure 1-2 One or more base stations 102 under discussion perform the procedure. Although method 500 is described below with respect to the various elements of base station 102, other components may also be used to implement one or more of the steps described herein.

[0072] In block 505, method 500 may include establishing a first signaling connection between a source IAB donor CU and at least one IAB-DU. In some examples, the first signaling connection between the source IAB donor CU and at least one IAB-DU may be one of an F1 connection (F1-C) or a Radio Resource Control (RRC) connection. The at least one IAB-DU may be one of an IAB donor DU or an IAB node DU. Aspects of block 505 may be referenced from... Figure 4 The transceiver 402, modem 414, and communication management component 450 described herein shall be used to perform this action. Thus, the communication management component 450, modem 414, processor 412, transceiver 402, and / or base station or one of its sub-components may define means for establishing a first signaling connection between the source IAB donor CU and at least one IAB-DU of the base station.

[0073] In block 510, method 500 may include establishing a second signaling connection between a source IAB donor CU and a target IAB donor CU. In some examples, the second signaling connection between the source IAB donor CU and the target IAB donor CU may be an F1 connection. In some examples, the IAB donor CU may be a base station CU. Aspects of block 510 may be derived from, as referenced... Figure 4 The transceiver 402, modem 414, and communication management component 450 described herein shall perform this action. Thus, the communication management component 450, modem 414, processor 412, transceiver 402, and / or base station or one of its sub-components may define means for establishing a second signaling connection between a source IAB donor CU and a target IAB donor CU.

[0074] In block 515, method 500 may include configuring a source IAB donor CU to act as a first agent for the at least one IAB-DU to transmit status information associated with the at least one IAB-DU to a target IAB donor CU. In some aspects, the status information associated with the at least one IAB-DU may include one or more of the following: the configuration of the cell served by the at least one IAB-DU, the context of a child node connected to the at least one IAB-DU, transport layer information regarding a Flow Control Transport Protocol (SCTP) connection carrying associated F1 connection signaling, transport layer information regarding a child node connected to the IAB-DU, or an identifier of one of the following: a base station DU, a base station CU, a connection between a base station DU and a base station CU, a flow between a base station DU and a base station CU, or a child node connected to the at least one IAB-DU. The status information may include transport layer information about the connection between the IAB donor CU and the at least one IAB-DU, an identifier of the connection between the IAB donor CU and the at least one IAB-DU, and an identifier of one or more of the following: the at least one IAB-DU, the IAB donor CU, or a child node connected to the at least one IAB-DU that is used on the connection between the IAB donor CU and the at least one IAB-DU.

[0075] The status information associated with the at least one IAB-DU transmitted from the source IAB donor CU to the target IAB donor CU may also include forwarding configuration information associated with the at least one IAB-DU that the source IAB donor CU had previously transmitted to the at least one IAB-DU. The status information associated with the at least one IAB-DU transmitted from the source IAB donor CU to the target IAB donor CU may also include forwarding configuration information of the at least one IAB-DU received from the at least one IAB-DU at the source IAB donor CU.

[0076] Configuring a source IAB donor CU to act as a first proxy for at least one IAB-DU may include determining an identifier of an IAB mobile terminal (IAB-MT) associated with the at least one IAB-DU, and transmitting the identifier of the IAB-MT to a target IAB donor CU to proxy the at least one IAB-DU. In other examples, configuring a source IAB donor CU to act as a first proxy for at least one IAB-DU may include determining an identifier associated with the at least one IAB-DU, and representing the source IAB donor CU as the at least one IAB-DU to the target IAB donor CU by using the identifier of the at least one IAB-DU to communicate with the target IAB donor CU.

[0077] All aspects of frame 515 can be referenced. Figure 4The transceiver 402, modem 414, and communication management component 450 described herein shall perform this action. Thus, the communication management component 450, modem 414, processor 412, transceiver 402, and / or base station or one of their sub-components may define means for configuring a source IAB donor CU to act as a first agent for at least one IAB-DU in order to transmit status information associated with that at least one IAB-DU to a target IAB donor CU.

[0078] In block 520, method 500 may include receiving state update information from a target IAB donor CU at an IAB donor CU. In some examples, receiving state update information from the target IAB donor CU may include receiving an updated base station CU identifier from the target IAB-CU at a source IAB-CU, and reconfiguring the cell identity (ID) for the cell served by the at least one IAB-DU at the source IAB-CU based at least in part on the updated base station CU identifier received from the target IAB-CU. The method may also include generating associated state update information based at least in part on the cell ID. Aspects of block 520 may be referenced from [reference needed]. Figure 4 The transceiver 402, modem 414, and communication management component 450 described herein shall perform this action. Thus, the communication management component 450, modem 414, processor 412, transceiver 402, and / or base station or one of its sub-components may define means for receiving state update information from a target IAB donor CU at the IAB donor CU. In block 525, method 500 may include configuring the source IAB donor CU to act as a second agent for the target IAB donor CU when transmitting state update information to the at least one IAB-DU. In some examples, the target IAB donor CU and the at least one IAB-DU may use one or both of state information or state update information to establish a TNLA directly between the target IAB donor CU and the at least one IAB-DU. In other examples, the source IAB donor CU may indicate a transport network layer (TNL) endpoint for the target IAB donor CU to the at least one IAB-DU, enabling the at least one IAB-DU to establish a transport network layer association (TNLA) between the target IAB donor CU and the at least one IAB-DU.

[0079] In some aspects, configuring a source IAB donor CU to act as a second agent for a target IAB donor CU may include determining an identifier associated with the target IAB donor CU, and representing the source IAB donor CU as the target IAB donor CU to the at least one IAB DU by employing the identifier of the target IAB donor CU to conduct communication with at least one IAB DU.

[0080] All aspects of frame 525 can be referenced. Figure 4 The transceiver 402, modem 414, and communication management component 450 described herein shall be used to perform this action. Thus, the communication management component 450, modem 414, processor 412, transceiver 402, and / or base station or any of its sub-components may define means for configuring a source IAB donor CU to act as a second agent for a target IAB donor CU when transmitting status update information to at least one IAB-DU.

[0081] Some additional example terms

[0082] Examples of implementations are described in the following numbered clauses.

[0083] 1. A method for wireless communication, comprising:

[0084] Establish a first signaling connection between the Source Integration Access and Backhaul (IAB) donor centralized unit (CU) and at least one IAB distributed unit (DU);

[0085] Establish a second signaling connection between the source IAB donor CU and the target IAB donor CU;

[0086] Configure the source IAB donor CU to act as the first agent of the at least one IAB-DU to transmit status information associated with the at least one IAB-DU to the target IAB donor CU;

[0087] Receive state update information from the target IAB donor CU at the source IAB donor CU; and

[0088] Configure the source IAB donor CU to act as a second agent of the target IAB donor CU when transmitting the status update information to the at least one IAB-DU.

[0089] 2. The method as described in Clause 1, wherein configuring the source IAB donor CU to act as a second agent for the target IAB donor CU comprises:

[0090] Determine the identifier associated with the target IAB donor CU; and

[0091] The source IAB donor CU is represented as the target IAB donor CU to the at least one IAB DU by using the identifier of the target IAB donor CU to communicate with the at least one IAB DU.

[0092] 3. The method as described in any of the preceding clauses 1-2, wherein configuring the source IAB donor CU to act as the first agent of the at least one IAB-CU comprises:

[0093] Determine the identifier associated with at least one IAB-DU; and

[0094] The source IAB donor CU is represented as the target IAB donor CU by using the identifier of the at least one IAB-DU to communicate with the target IAB donor CU.

[0095] 4. The method as described in any of the preceding clauses 1-3, wherein configuring the source IAB donor CU to act as the first agent of the at least one IAB-CU comprises:

[0096] Determine the identifier of the IAB mobile terminal (IAB-MT) associated with the at least one IAB-DU; and

[0097] The identifier of the IAB-MT is transmitted to the target IAB donor CU to act as an agent for the at least one IAB-DU.

[0098] 5. The method as described in any of the preceding clauses 1-4, wherein the status information associated with the at least one IAB-DU includes one or more of the following:

[0099] The configuration of the cellular cells served by at least one IAB-DU,

[0100] The context connected to the child node of at least one IAB-DU,

[0101] Transport layer information regarding the connection between the IAB donor CU and the at least one IAB-DU, the identifier of the connection between the IAB donor CU and the at least one IAB-DU, or

[0102] The identifier of one or more of the following: the at least one IAB-DU, the IAB donor CU, or a child node connected to the at least one IAB-DU used on the connection between the IAB donor CU and the at least one IAB-DU.

[0103] 6. The method as described in any of the preceding clauses 1-5, wherein the status information associated with the at least one IAB-DU transmitted from the IAB donor CU to the target IAB donor includes:

[0104] Forward the configuration information of the at least one IAB-DU received from the at least one IAB-DU at the source IAB donor CU.

[0105] 7. The method as described in any of the preceding clauses 1-6, wherein the status information associated with the at least one IAB-DU transmitted from the IAB donor CU to the target IAB donor CU includes:

[0106] Forward the configuration information associated with the at least one IAB-DU that the source IAB donor CU has previously transmitted to the at least one IAB-DU to the target IAB donor CU.

[0107] 8. The method as described in any of the preceding clauses 1-7, wherein receiving the status update information from the target IAB donor CU includes:

[0108] Receive the updated base station CU identifier from the target IAB-CU at the source IAB-CU;

[0109] The cell identity (ID) of the cell served by the at least one IAB-DU is reconfigured at the source IAB-CU, at least in part, based on the updated base station CU identifier received from the target IAB-CU; and

[0110] The associated status update information is generated at least in part based on the cell ID.

[0111] 9. The method as described in any of the preceding clauses 1-8, wherein the first signaling connection between the source IAB donor CU and the at least one IAB-DU is one of an F1 connection (F1-C) or a Radio Resource Control (RRC) connection, and

[0112] The second signaling connection between the source IAB donor CU and the target IAB donor CU is the F1 connection.

[0113] 10. The method as described in any of the preceding clauses 1-9, wherein the at least one IAB-DU is one of an IAB donor DU or an IAB node DU.

[0114] 11. The method as described in any of the preceding clauses 1-10, wherein the target IAB donor CU and the at least one IAB-DU use one or both of the status information or the status update information to establish a transport network layer association (TNLA) directly between the target IAB donor CU and the at least one IAB-DU.

[0115] 12. The method as described in any of the preceding clauses 1-11, wherein the source IAB donor CU instructs the at least one IAB-DU to have a transport network layer (TNL) endpoint for the target IAB donor CU such that the at least one IAB-DU is able to establish a transport network layer association (TNLA) between the target IAB donor CU and the at least one IAB-DU.

[0116] 13. The method as described in any of the preceding clauses 1-12, wherein the IAB donor CU is a base station CU.

[0117] 14. An apparatus for wireless communication, comprising:

[0118] At least one processor;

[0119] and a memory coupled to the at least one processor, the memory including instructions executable by the at least one processor to cause the device to:

[0120] Establish a first signaling connection between the Source Integration Access and Backhaul (IAB) donor centralized unit (CU) and at least one IAB distributed unit (DU);

[0121] Establish a second signaling connection between the source IAB donor CU and the target IAB donor CU;

[0122] Configure the source IAB donor CU to act as the first agent of the at least one IAB-DU to transmit status information associated with the at least one IAB-DU to the target IAB donor CU;

[0123] Receive state update information from the target IAB donor CU at the source IAB donor CU; and

[0124] Configure the source IAB donor CU to act as a second agent of the target IAB donor CU when transmitting the status update information to the at least one IAB-DU.

[0125] 15. The apparatus of Clause 14, wherein instructions for configuring the source IAB donor CU to act as a second agent of the target IAB donor CU can be further executed by the at least one processor to enable the apparatus to:

[0126] Determine the identifier associated with the target IAB donor CU; and

[0127] The source IAB donor CU is represented as the target IAB donor CU to the at least one IAB DU by using the identifier of the target IAB donor CU to communicate with the at least one IAB DU.

[0128] 16. The apparatus as described in any of the preceding clauses 14-15, wherein the instructions for configuring the source IAB donor CU to act as a first agent of the at least one IAB-DU can be further executed by the at least one processor to cause the apparatus to:

[0129] Determine the identifier associated with at least one IAB-DU; and

[0130] The source IAB donor CU is represented as the target IAB donor CU by using the identifier of the at least one IAB-DU to communicate with the target IAB donor CU.

[0131] 17. The apparatus as described in any of the preceding clauses 14-16, wherein the instructions for configuring the source IAB donor CU to act as the first agent of the at least one IAB-DU can be further executed by the at least one processor to cause the apparatus to:

[0132] Determine the identifier of the IAB mobile terminal (IAB-MT) associated with the at least one IAB-DU; and

[0133] The identifier of the IAB-MT is transmitted to the target IAB donor CU to act as an agent for the at least one IAB-DU.

[0134] 18. The device as described in any of the preceding clauses 14-17, wherein the status information associated with the at least one IAB-DU includes one or more of the following:

[0135] The configuration of the cellular cells served by at least one IAB-DU,

[0136] The context connected to the child node of at least one IAB-DU,

[0137] Transport layer information regarding the connection between the IAB donor CU and the at least one IAB-DU, the identifier of the connection between the IAB donor CU and the at least one IAB-DU, or

[0138] The identifier of one or more of the following: the at least one IAB-DU, the IAB donor CU, or a child node connected to the at least one IAB-DU used on the connection between the IAB donor CU and the at least one IAB-DU.

[0139] 19. The apparatus as described in any of the preceding clauses 14-18, wherein the status information associated with the at least one IAB-DU transmitted from the IAB donor CU to the target IAB donor includes:

[0140] Forward the configuration information of the at least one IAB-DU received from the at least one IAB-DU at the source IAB donor CU.

[0141] 20. The apparatus as described in any of the preceding clauses 14-19, wherein the status information associated with the at least one IAB-DU transmitted from the IAB donor CU to the target IAB donor CU includes:

[0142] Forward the configuration information associated with the at least one IAB-DU that the source IAB donor CU has previously transmitted to the at least one IAB-DU to the target IAB donor CU.

[0143] 21. The apparatus of any of the preceding clauses 14-20, wherein the instructions for receiving the status update information from the target IAB donor CU can be executed by the at least one processor to cause the apparatus to:

[0144] Receive the updated base station CU identifier from the target IAB-CU at the source IAB-CU;

[0145] The cell identity (ID) of the cell served by the at least one IAB-DU is reconfigured at the source IAB-CU, at least in part, based on the updated base station CU identifier received from the target IAB-CU; and

[0146] The associated status update information is generated at least in part based on the cell ID.

[0147] 22. The apparatus as described in any of the preceding clauses 14-21, wherein the first signaling connection between the source IAB donor CU and the at least one IAB-DU is either an F1 connection (F1-C) or a Radio Resource Control (RRC) connection, and

[0148] The second signaling connection between the source IAB donor CU and the target IAB donor CU is the F1 connection.

[0149] 23. The apparatus as described in any of the preceding clauses 14-22, wherein the at least one IAB-DU is one of an IAB donor DU or an IAB node DU.

[0150] 24. The apparatus described in any of the preceding clauses 14-23, wherein the target IAB donor CU and the at least one IAB-DU use one or both of the status information or the status update information to establish a transport network layer association (TNLA) directly between the target IAB donor CU and the at least one IAB-DU.

[0151] 25. The apparatus of any of the preceding clauses 14-24, wherein the source IAB donor CU instructs the at least one IAB-DU to have a transport network layer (TNL) endpoint for the target IAB donor CU such that the at least one IAB-DU is able to establish a transport network layer association (TNLA) between the target IAB donor CU and the at least one IAB-DU.

[0152] 26. The apparatus as described in any of the preceding clauses 14-25, wherein the IAB donor CU is a base station CU.

[0153] 27. A non-transient computer-readable medium storing instructions executable by a processor for wireless communication, comprising instructions for the following operations:

[0154] A first signaling connection is established between the source integrated access and backhaul (IAB) donor centralized unit (CU) of the base station and at least one IAB distributed unit (DU);

[0155] Establish a first signaling connection between the Source Integration Access and Backhaul (IAB) donor centralized unit (CU) and at least one IAB distributed unit (DU);

[0156] Establish a second signaling connection between the source IAB donor CU and the target IAB donor CU;

[0157] Configure the source IAB donor CU to act as the first agent of the at least one IAB-DU to transmit status information associated with the at least one IAB-DU to the target IAB donor CU;

[0158] Receive state update information from the target IAB donor CU at the source IAB donor CU; and

[0159] Configure the source IAB donor CU to act as a second agent of the target IAB donor CU when transmitting the status update information to the at least one IAB-DU.

[0160] 28. The non-transient computer-readable medium as described in Clause 27, wherein the second agent configuring the source IAB donor CU to act as the target IAB donor CU further includes instructions for the following operations:

[0161] Determine the identifier associated with the target IAB donor CU; and

[0162] The source IAB donor CU is represented as the target IAB donor CU to the at least one IAB DU by using the identifier of the target IAB donor CU to communicate with the at least one IAB DU.

[0163] 29. The non-transient computer-readable medium as described in Clause 27 or 28, wherein configuring the source IAB donor CU to act as the first agent of the at least one IAB-DU further includes instructions for the following operations:

[0164] Determine the identifier associated with at least one IAB-DU; and

[0165] The source IAB donor CU is represented as the target IAB donor CU by using the identifier of the at least one IAB-DU to communicate with the target IAB donor CU.

[0166] 30. A device for wireless communication, comprising:

[0167] A means for establishing a first signaling connection between a Source Integrated Access and Backhaul (IAB) donor centralized unit (CU) and at least one IAB distributed unit (DU);

[0168] A means for establishing a second signaling connection between the source IAB donor CU and the target IAB donor CU;

[0169] A means for configuring the source IAB donor CU to act as the first agent of the at least one IAB-DU, so as to transmit status information associated with the at least one IAB-DU to the target IAB donor CU;

[0170] A means for receiving status update information from the target IAB donor CU at the source IAB donor CU; and

[0171] A means for configuring the source IAB donor CU to act as a second agent of the target IAB donor CU when transmitting the status update information to the at least one IAB-DU.

[0172] 31. The apparatus as described in Clause 30, wherein the means for configuring the source IAB donor CU to act as a second agent of the target IAB donor CU comprises:

[0173] A means for determining an identifier associated with the target IAB donor CU; and

[0174] A means for representing the source IAB donor CU as the target IAB donor CU to the at least one IAB DU by employing the identifier of the target IAB donor CU to communicate with the at least one IAB-DU.

[0175] 32. The apparatus as described in any of the preceding clauses 30-31, wherein the means for configuring the source IAB donor CU to act as a first agent of the at least one IAB-CU comprises:

[0176] A means for determining an identifier associated with at least one IAB-DU; and

[0177] A means for representing the source IAB donor CU as the target IAB donor CU by employing the identifier of the at least one IAB-DU to communicate with the target IAB donor CU.

[0178] 33. The device as described in any of the preceding clauses 30-32, wherein configuring the source IAB donor CU to act as a first agent of the at least one IAB-CU includes:

[0179] A means for determining an identifier of an IAB mobile terminal (IAB-MT) associated with the at least one IAB-DU; and

[0180] A means for transmitting the identifier of the IAB-MT to the target IAB donor CU to proxy the at least one IAB-DU.

[0181] 34. The device as described in any of the preceding clauses 30-33, wherein the status information associated with the at least one IAB-DU includes one or more of the following:

[0182] The configuration of the cellular cells served by at least one IAB-DU,

[0183] The context connected to the child node of at least one IAB-DU,

[0184] Transport layer information regarding the connection between the IAB donor CU and the at least one IAB-DU, the identifier of the connection between the IAB donor CU and the at least one IAB-DU, or

[0185] The identifier of one or more of the following: the at least one IAB-DU, the IAB donor CU, or a child node connected to the at least one IAB-DU used on the connection between the IAB donor CU and the at least one IAB-DU.

[0186] 35. The apparatus as described in any of the preceding clauses 30-34, wherein the status information associated with the at least one IAB-DU transmitted from the IAB donor CU to the target IAB donor includes:

[0187] A means for forwarding configuration information of the at least one IAB-DU received at the source IAB donor CU from the at least one IAB-DU.

[0188] 36. The apparatus as described in any of the preceding clauses 30-36, wherein the status information associated with the at least one IAB-DU transmitted from the IAB donor CU to the target IAB donor CU includes:

[0189] A means for forwarding configuration information associated with the at least one IAB-DU that the source IAB donor CU has previously transmitted to the at least one IAB-DU.

[0190] 39. The device as described in any of the preceding clauses 30-38, wherein the means for receiving the status update information from the target IAB donor CU includes:

[0191] A means for receiving an updated base station CU identifier from the target IAB-CU at the source IAB-CU;

[0192] A means for reconfiguring the cell identity (ID) of the cell served by the at least one IAB-DU at the source IAB-CU based at least in part on the updated base station CU identifier received from the target IAB-CU; and

[0193] A means for generating associated status update information based at least in part on the cell ID.

[0194] 40. The equipment as described in any of the preceding clauses 30-39, wherein the first signaling connection between the source IAB donor CU and the at least one IAB-DU is either an F1 connection (F1-C) or a Radio Resource Control (RRC) connection, and

[0195] The second signaling connection between the source IAB donor CU and the target IAB donor CU is the F1 connection.

[0196] 41. The device as described in any of the preceding clauses 30-40, wherein the at least one IAB-DU is either an IAB donor DU or an IAB node DU.

[0197] 42. The device described in any of the preceding clauses 30-41, wherein the target IAB donor CU and the at least one IAB-DU use one or both of the status information or the status update information to establish a transport network layer association (TNLA) directly between the target IAB donor CU and the at least one IAB-DU.

[0198] 43. The device as described in any of the preceding clauses 30-42, wherein the source IAB donor CU instructs the at least one IAB-DU to have a transport network layer (TNL) endpoint for the target IAB donor CU such that the at least one IAB-DU is able to establish a transport network layer association (TNLA) between the target IAB donor CU and the at least one IAB-DU.

[0199] 44. The equipment as described in any of the preceding clauses 30-43, wherein the IAB donor CU is a base station CU.

[0200] The detailed description above, in conjunction with the accompanying drawings, describes examples and does not represent only examples that can be implemented or fall within the scope of the claims. The term "example" as used in this description means "serving as an example, instance, or illustration," and not "superior to" or "better than other examples." This detailed description includes specific details to provide an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0201] Information and signals can be represented using any of a wide variety of different techniques and technologies. For example, data, instructions, commands, information, signals, bits, symbols, and chips, which may be referred to throughout the above description, can be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or light particles, computer-executable code or instructions stored on a computer-readable medium, or any combination thereof.

[0202] The various explanatory frames and components described herein can be implemented or executed using specially programmed devices, such as, but not limited to, processors, digital signal processors (DSPs), ASICs, FPGAs, or other programmable logic devices designed to perform the functions described herein, discrete gate or transistor logic, discrete hardware components, or any combination thereof. A specially programmed processor may be a microprocessor, but in alternatives, the processor may be any conventional processor, controller, microcontroller, or state machine. A specially programmed processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors cooperating with a DSP core, or any other such configuration.

[0203] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored as one or more instructions or codes on or transmitted via a non-transient computer-readable medium. Other examples and implementations fall within the scope and spirit of this disclosure and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software, hardware, firmware, hardwired, or any combination thereof executed by a specially programmed processor. Features implementing the functions may also be physically located in various locations, including being distributed such that portions of the functions are implemented at different physical locations. Moreover, as used herein (including in the claims), the "or" used in a list of items followed by "at least one of" indicates a disjunctive enumeration, such that an enumeration such as "at least one of A, B, or C" represents A or B or C or AB or AC or BC or ABC (i.e., A and B and C).

[0204] Computer-readable media includes both computer storage media and communication media, encompassing any medium that facilitates the transfer of a computer program from one location to another. Storage media can be any available medium accessible to a general-purpose or special-purpose computer. By way of example and not limitation, computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disc storage, disk storage or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible to a general-purpose or special-purpose computer, or a general-purpose or special-purpose processor. Similarly, any connection is also legitimately referred to as computer-readable media. For example, if software is transmitted from a website, server, or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then that coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of media. As used in this article, disk and disc include compact discs (CDs), laser discs, optical discs, digital multi-purpose discs (DVDs), floppy disks, and Blu-ray discs. Disks often magnetically reproduce data, while discs optically reproduce data using lasers. Combinations of these media are also included within the scope of computer-readable media.

[0205] The detailed description above, taken in conjunction with the accompanying drawings, is intended to describe various configurations and is not intended to represent the only configuration in which the concepts described herein can be practiced. This detailed description includes specific details to provide a thorough understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts can be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form to avoid obscuring such concepts.

[0206] Various apparatuses and methods are also described with reference to several aspects of the telecommunications system. These apparatuses and methods are described in detail and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as “elements”). These elements can be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0207] As an example, an element, or any part of an element, or any combination of elements, may be implemented as a processing system comprising one or more processors. Examples of processors include: microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, system-on-a-chip (SoCs), baseband processors, field-programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuitry, and other suitable hardware configured to perform the various functionalities described throughout this disclosure. One or more processors in the processing system may execute software. Software should be broadly interpreted as instructions, instruction sets, code, code segments, program code, programs, subroutines, software components, applications, software applications, software packages, routines, subroutines, objects, executables, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description languages, or other terms.

[0208] It should be noted that the techniques described herein can be used in various wireless communication networks, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and other systems. The terms "system" and "network" are often used interchangeably. CDMA systems can implement radio technologies such as CDMA2000 and Universal Terrestrial Radio Access (UTRA). CDMA2000 encompasses the IS-2000, IS-95, and IS-856 standards. IS-2000 versions 0 and A are commonly referred to as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) is commonly referred to as CDMA2000 1xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. TDMA systems can implement radio technologies such as Global System for Mobile Communications (GSM). OFDMA systems can implement technologies such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE 902.11 (Wi-Fi), IEEE 902.16 (WiMAX), IEEE 902.20, and Flash-OFDM. TMRadio technologies such as UTRA and E-UTRA are part of the Universal Mobile Telecommunications System (UMTS). 3GPP Long Term Evolution (LTE) and LTE-A Advanced (LTE-A) are new UMTS versions using E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization called the Third Generation Partnership Project (3GPP). CDMA2000 and UMB are described in documents from an organization called the Third Generation Partnership Project 2 (3GPP2). The technologies described herein can be used with the systems and radio technologies mentioned above, as well as with other systems and radio technologies, including cellular (e.g., LTE) communications sharing a RF band. However, the following description describes LTE / LTE-A and / or 5G New Radio (NR) systems for illustrative purposes, and the terms LTE or 5G NR are used in most of the following description, but these technologies can also be applied beyond LTE / LTE-A and 5G NR applications (e.g., to other next-generation communication systems).

[0209] The prior description of this disclosure is provided to enable those skilled in the art to make or use it. Various modifications to this disclosure will readily be apparent to those skilled in the art, and the common principles defined herein can be applied to other variations without departing from the spirit or scope of this disclosure. Furthermore, although elements of the described aspects and / or embodiments may be described or claimed in the singular, the plural is also contemplated unless explicitly stated to be limited to the singular. Additionally, all or part of any aspect and / or embodiment may be used in conjunction with all or part of any other aspect and / or embodiment unless otherwise stated. Thus, this disclosure is not limited to the examples and designs described herein, but should be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication, comprising: establishing a first signaling connection between a source integrated access and backhaul (IAB) donor central unit (CU) and at least one IAB-distributed unit (DU); establishing a second signaling connection between the source IAB donor CU and a target IAB donor CU; configuring the source IAB donor CU to function as a first proxy for the at least one IAB-DU to communicate state information associated with the at least one IAB-DU to the target IAB donor CU; receiving, at the source IAB donor CU, state update information from the target IAB donor CU; and configuring the source IAB donor CU to function as a second proxy for the target IAB donor CU in communicating the state update information to the at least one IAB-DU, wherein configuring the source IAB donor CU to function as the second proxy for the target IAB donor CU comprises: determining an identifier associated with the target IAB donor CU; and representing the source IAB donor CU as the target IAB donor CU to the at least one IAB-DU by employing the identifier of the target IAB donor CU for communications with the at least one IAB-DU.

2. The method of claim 1, wherein, configuring the source IAB donor CU to function as the first proxy for the at least one IAB-CU comprises: determining an identifier associated with at least one IAB-DU; and representing the source IAB donor CU as the at least one IAB-DU to the target IAB donor CU by employing the identifier of the at least one IAB-DU for communications with the target IAB donor CU.

3. The method of claim 1, wherein, configuring the source IAB donor CU to function as the first proxy for the at least one IAB-CU comprises: determining an identifier of an IAB-mobile termination (IAB-MT) associated with the at least one IAB-DU; and communicating the identifier of the IAB-MT to the target IAB donor CU to proxy the at least one IAB-DU.

4. The method of claim 1, wherein, the state information associated with the at least one IAB-DU comprises one or more of: a configuration of a cell served by the at least one IAB-DU, a context of a child node connected to the at least one IAB-DU, transport layer information about a connection between the IAB donor CU and the at least one IAB-DU, an identifier of a connection between the IAB donor CU and the at least one IAB-DU, or an identifier of one or more of: the at least one IAB-DU, the IAB donor CU, or a child node connected to the at least one IAB-DU used on a connection between the IAB donor CU and the at least one IAB-DU.

5. The method of claim 1, wherein, the state information associated with the at least one IAB-DU communicated from the IAB donor CU to the target IAB donor comprises: forwarding configuration information of the at least one IAB-DU received at the source IAB-donor CU from the at least one IAB-DU.

6. The method of claim 1, wherein, the state information associated with the at least one IAB-DU communicated from the IAB-donor CU to the target IAB-donor CU includes: forwarding configuration information associated with the at least one IAB-DU that the source IAB-donor CU has previously communicated to the at least one IAB-DU to the target IAB-donor CU.

7. The method of claim 1, wherein, receiving the state update information from the target IAB-CU includes: receiving an updated base station CU identifier at the source IAB-CU from the target IAB-CU; reconfiguring a cell identity (ID) for a cell served by the at least one IAB-DU at the source IAB-CU based at least in part on the updated base station CU identifier received from the target IAB-CU; and generating associated state update information based at least in part on the cell ID.

8. The method of claim 1, wherein, the first signaling connection between the source IAB-donor CU and the at least one IAB-DU is one of an Fl connection (Fl-C) or a radio resource control (RRC) connection, and wherein the second signaling connection between the source IAB-donor CU and the target IAB-donor CU is the Fl connection.

9. The method of claim 1, wherein, the at least one IAB-DU is one of an IAB-donor DU or an IAB-node DU.

10. The method of claim 1, wherein, the target IAB-donor CU and the at least one IAB-DU use one or both of the state information or the state update information to establish a transport network layer association (TNLA) directly between the target IAB-donor CU and the at least one IAB-DU.

11. The method of claim 1, wherein, the source IAB-donor CU indicates a transport network layer (TNL) endpoint for the target IAB-donor CU to the at least one IAB-DU to enable the at least one IAB-DU to establish a transport network layer association (TNLA) TNLA between the target IAB-donor CU and the at least one IAB-DU.

12. The method of claim 1, wherein, the IAB-donor CU is a base station CU.

13. An apparatus for wireless communication, comprising: at least one processor; and a memory coupled to the at least one processor comprising instructions executable by the at least one processor to cause the apparatus to: establish a first signaling connection between a source integrated access and backhaul (IAB) donor centralized unit (CU) and at least one IAB-distributed unit (DU); establish a second signaling connection between the source IAB-donor CU and a target IAB-donor CU; configure the source IAB-donor CU to function as a first proxy for the at least one IAB-DU to communicate state information associated with the at least one IAB-DU to the target IAB-donor CU; receive state update information at the source IAB-donor CU from the target IAB-donor CU; and configuring the source IAB-donor CU to act as a second proxy for the target IAB-donor CU in communicating the state information to the at least one IAB-DU, wherein the instructions to configure the source IAB-donor CU to act as the second proxy for the target IAB-donor CU can be further executed by the at least one processor to cause the apparatus to: determine an identifier associated with the target IAB-donor CU; and represent the source IAB-donor CU to the at least one IAB-DU as the target IAB-donor CU by employing the identifier of the target IAB-donor CU in communications with the at least one IAB-DU. the instructions to configure the source IAB-donor CU to act as the first proxy for the at least one IAB-DU can be further executed by the at least one processor to cause the apparatus to:

14. The apparatus of claim 13, wherein, determine an identifier associated with at least one IAB-DU; and represent the source IAB-donor CU to the target IAB-donor CU as the at least one IAB-DU by employing the identifier of the at least one IAB-DU in communications with the target IAB-donor CU. the instructions to configure the source IAB-donor CU to act as the first proxy for the at least one IAB-DU can be further executed by the at least one processor to cause the apparatus to: determine an identifier of an IAB-mobile termination (IAB-MT) associated with the at least one IAB-DU; and 15. The apparatus of claim 13, wherein, transmit the identifier of the IAB-MT to the target IAB-donor CU to proxy the at least one IAB-DU. the state information associated with the at least one IAB-DU includes one or more of: a configuration of a cell served by the at least one IAB-DU, 16. The apparatus of claim 13, wherein, a context of a child node connected to the at least one IAB-DU, transport layer information regarding a connection between the IAB-donor CU and the at least one IAB-DU, an identifier of a connection between the IAB-donor CU and the at least one IAB-DU, or an identifier of one or more of: the at least one IAB-DU, the IAB-donor CU, or a child node connected to the at least one IAB-DU used on a connection between the IAB-donor CU and the at least one IAB-DU. transmitting, from the IAB-donor CU to the target IAB-donor, the state information associated with the at least one IAB-DU includes: forwarding configuration information of the at least one IAB-DU received at the source IAB-donor CU from the at least one IAB-DU.

17. The apparatus of claim 13, wherein, transmitting, from the IAB-donor CU to the target IAB-donor CU, the state information associated with the at least one IAB-DU includes: forwarding, to the target IAB-donor CU, configuration information associated with the at least one IAB-DU that the source IAB-donor CU has previously transmitted to the at least one IAB-DU.

18. The apparatus of claim 13, wherein, ​ ​ 19. The apparatus of claim 13, wherein, instructions to receive the state update information from the target IAB-donor CU can be executed by the at least one processor to cause the apparatus to: receive, at the source IAB-CU, an updated base station CU identifier from the target IAB-CU; reconfigure, at the source IAB-CU, a cell identity (ID) for a cell served by the at least one IAB-DU based at least in part on the updated base station CU identifier received from the target IAB-CU; and generate associated state update information based at least in part on the cell ID.

20. The apparatus of claim 13, wherein, the first signaling connection between the source IAB-donor CU and the at least one IAB-DU is one of an F1 connection (F1-C) or a radio resource control (RRC) connection, and wherein the second signaling connection between the source IAB-donor CU and the target IAB-donor CU is the F1 connection.

21. The apparatus of claim 13, wherein, the at least one IAB-DU is one of an IAB-donor DU or an IAB-node DU.

22. The apparatus of claim 13, wherein, the target IAB-donor CU and the at least one IAB-DU use one or both of the state information or the state update information to establish a transport network layer association (TNLA) directly between the target IAB-donor CU and the at least one IAB-DU.

23. The apparatus of claim 13, wherein, the source IAB-donor CU indicates to the at least one IAB-DU a transport network layer (TNL) endpoint for the target IAB-donor CU to enable the at least one IAB-DU to establish a transport network layer association (TNLA) TNLA between the target IAB-donor CU and the at least one IAB-DU.

24. The apparatus of claim 13, wherein, the IAB-donor CU is a base station CU.

25. A non-transitory computer-readable medium storing instructions executable by a processor for wireless communication, comprising instructions for: establishing a first signaling connection between a source integrated access and backhaul (IAB) donor centralized unit (CU) and at least one IAB distributed unit (DU) of a base station; establishing a first signaling connection between a source integrated access and backhaul (IAB) donor centralized unit (CU) and at least one IAB distributed unit (DU); establishing a second signaling connection between the source IAB-donor CU and a target IAB-donor CU; configuring the source IAB-donor CU to function as a first proxy for the at least one IAB-DU to communicate state information associated with the at least one IAB-DU to the target IAB-donor CU; receiving, at the source IAB-donor CU, state update information from the target IAB-donor CU; and configuring the source IAB-donor CU to function as a second proxy for the target IAB-donor CU in communicating the state update information to the at least one IAB-DU, wherein configuring the source IAB-donor CU to function as the second proxy for the target IAB-donor CU further comprises instructions for: determining an identifier associated with the target IAB-donor CU; and representing the source IAB-donor CU to the at least one IAB-DU as the target IAB-donor CU by employing the identifier associated with the target IAB-donor CU for communication with the at least one IAB-DU.

26. The non-transitory computer readable medium of claim 25, wherein, configuring the source IAB-donor CU to function as the first proxy for the at least one IAB-DU further includes instructions for: determining an identifier associated with at least one IAB-DU; and representing the source IAB-donor CU to the at least one IAB-DU as the target IAB-donor CU by employing the identifier associated with the target IAB-donor CU for communication with the at least one IAB-DU.

27. An apparatus for wireless communication, comprising: means for establishing a first signaling connection between a source integrated access and backhaul (IAB) donor centralized unit (CU) and at least one IAB-distributed unit (DU); means for establishing a second signaling connection between the source IAB-donor CU and a target IAB-donor CU; means for configuring the source IAB-donor CU to function as a first proxy for the at least one IAB-DU to communicate state information associated with the at least one IAB-DU to the target IAB-donor CU; means for receiving state update information at the source IAB-donor CU from the target IAB-donor CU; and means for configuring the source IAB-donor CU to function as a second proxy for the target IAB-donor CU when communicating the state update information to the at least one IAB-DU, wherein the means for configuring the source IAB-donor CU to function as the second proxy for the target IAB-donor CU includes: means for determining an identifier associated with the target IAB-donor CU; and means for representing the source IAB-donor CU to the at least one IAB-DU as the target IAB-donor CU by employing the identifier associated with the target IAB-donor CU for communication with the at least one IAB-DU.

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