Architecture of a multi-hop relay network

Abstract

A method (700) by a relay node of a relay network includes, based on whether the relay node is at a first hop of the relay network, establishing (702) a connection with a core network for the relay node. When the relay node is not at the first hop of a relay network, the connection includes a data radio bearer, DRB, without a user plane tunnel. Alternatively, when the relay node is at the first hop of a relay network, the connection includes a DRB and a user plane tunnel.

Description

[0001] ARCHITECTURE OF A MULTI-HOP RELAY NETWORK

[0002] TECHNICAL FIELD

[0003] The present disclosure relates, in general, to wireless communications and, more particularly, systems and methods including an architecture for a multi-hop relay network.

[0004] BACKGROUND

[0005] Multi-hop connection via infrastructure-based wireless relay targets are used for rapid, temporary, flexible, and / or low-cost deployments. Examples deployments include:

[0006] • extending Enhanced Mobile Broadband (eMBB) service coverage such as, for example, to support Fixed Wireless Access (FWA), small cell backhauling in particular on high frequency, and / or temporary coverage (e.g., initial phase of network planning (trial of a possibly permanent site));

[0007] • providing emergency coverage during times of, for example, disasters, public safety, and / or defense;

[0008] • providing global coverage using Low Earth Orbit (LEO) satellites with intersatellite links; and

[0009] • improving capacity in, for example, sport / musical events with additional network nodes.

[0010] 3rdGeneration Partnership (3GPP) has standardized in both 4thGeneration (4G) and 5thGeneration (5G) two such technical solutions: Long Term Evolution (LTE) relay and Integrated Access and Backhaul (IAB), which rely on the principles of proxy and relaying / routing on the Layer 2 of the Radio Access Network (RAN) protocol stack, respectively. During the 4G standardization work leading to the LTE relay solution, different architectures were considered in the technical report 3GPP TR 36.806. During the 5G standardization leading to IAB 3GPP TR 38.874, vl6.0.0, which is a study report on IAB, was published. The study report discussed two solutions: serialized PDU session and tunneled Packet Data Unit (PDU) session were discussed, but neither was standardized in 5G. Relay Architectures for E-UTRA (3GPP PR 36.806)

[0011] The architectural approach discussed for LTE relaying is that relaying is achieved through a user plane connection which spans from a relay node (RN) to a Serving Gateway (SGW) / Packet Network Gateway (PGW). In order to avoid packets associated to relaying traffic having to always traverse two nodes (a Donor eNodeB (DeNB) and an PGW / SGW) and be processed twice, one of the architectural solutions considered for LTE, introduced the idea of integrating the SGW7PGW functionality associated to a relay node (RN) into the DeNB to which the RN is connected. This architectural solution is shown in FIGURE 1, which illustrates a user plane protocol stack for Alt. 3 of architecture A. In this way, the packets associated to relaying traffic are processed only in a single node, resulting in optimization of routing paths. Integrating the SGW7PGW functionality into the DeNB, among other things, means for example that the DeNB will classify packets into RN Evolved Packet System (EPS) bearer (functionality done in legacy 4G system by PGW) for traffic towards the RN, and that the RN’s bearer will terminate in the DeNB (instead of terminating at PGW).

[0012] Integrated Access Backhaul

[0013] Integrated access and backhaul (IAB) enables wireless relaying in Next Generation- Radio Access Network (NG-RAN) and is discussed in 3GPP TS 38.300, vl7.3.0 and 3GPP TS 36.300, vl7.3.0, clause 4.7. The relaying node, referred to as lAB-node, supports access and backhauling via New Radio (NR) (more relevantly, using the same radio interface as a baseline). The terminating node of NR backhauling on network side is referred to as the lAB-donor, which represents a gNodeB (gNB) with additional functionality to support IAB. Backhauling can occur via a single or via multiple hops. FIGURE 2 is a reproduction of Figure 4.7.1-1 from 3GPP TS 38.300 and illustrates the IAB architecture, which includes an lAB-node using standalone (SA) mode with Next Generation Core (NGC).

[0014] FIGURE 3 is a reproduction of Figure 4.7.1-2 from 3GPP TS 38.300 and illustrates the parent and child-node relationship for an lAB-node.

[0015] The overall architecture for IAB is based on the Centralized Unit (CU) / Distributed Unit (DU) split. The specifically DU contains Physical (PHY), Medium Access Control (MAC) and Radio Link Control (RLC) layers while CU contains Packet Data Convergence Protocol (PDCP) layer and Service Data Adaption Protocol (SDAP) CU-User Plane (CULT) or Radio Resource Control (RRC) CU-Control Plane (CU-CP). One IAB node has both a gNB-function side IAB -Distributed Unit (IAB-DU) and a User Equipment (UE)-function side lAB-Mobile Termination (IAB-MT). The IAB donor connects to the wired network and has both CU and DU. The standardized interface between the CU and the DU is the Fl interface. New Radio (NR) L2 lower layer protocols (RLC, MAC) and LI Uu interface (PHY), together with the lAB-specific routing protocol (i.e., Backhaul Adaptation Protocol (BAP) sublayer) for multi -hop, provides low layer connections to convey Fl messages.

[0016] Proposal in IAB Study Item

[0017] An idea similar to LTE relay Alt 3, which is discussed above, has been revealed in 3GPP IAB study item discussion in 5G. See, R3-180792, Section 2.2.2. It is described in that document that the IAB node 1 transmits a packet via backhaul link to IAB node 2. Upon receiving such packet, IAB node 2 detects the IP header. If the destination IP address is not for itself, IAB node 2 will route this packet to next node according to the pre- established routing table. Finally, the packet arrives anchor node, and anchor node forward it to UE’s User Plane Function (UPF).

[0018] FIGURE 4 is a reproduction of Figure 8 from R3-180792, which illustrates Layer 3 user plane radio protocol stack.

[0019] Serialized PDU Session

[0020] FIGURES 5A-5B illustrate a serialized PDU session. Specifically, FIGURE 5A illustrates Architecture 2a for serialized PDU session, as disclosed in Error! Reference source not found.. The principle is a serialization of user plane with Internet Protocol (IP) routing. Relay node is a combination of UE and gNB plus a UPF, with routing in between UE and UPF. In more detail, relay node connects to a UPF on upstream relay / network nodes and obtains an IP connectivity via this PDU session.

[0021] Each relay UE (rUE) establishes a PDU Session terminated in a UPF located at the relay node the rUE is connected to. When a PDU Session is established, the traffic between UPF and gNB is handled at level of Quality of Service (QoS) Flow of PDU Session. The traffic is exchanged using the N3 tunnel. The gNB is aware of which N3 tunnel termination to use for traffic of a QoS Flow towards the UPF, and the UPF is aware of which N3 tunnel termination to use for traffic of a QoS Flow towards the gNB. More precisely, in the uplink direction, the UE uses QoS rules to map uplink packets to their respective QoS Flows of the associated PDU Session. The UE transfers the traffic to the gNB by mapping QoS Flows into corresponding radio bearers. Finally, the gNB maps traffic received over Data Radio Bearers (DRBs) to the respective QoS Flows of the PDU Session and the traffic is put into the corresponding N3 tunnel towards the UPF. In the downlink direction (from network to the UE), the UPF uses Packet Detection Rules (PDRs) to map downlink packets to their respective QoS Flows of the PDU Session. Packets are put into the corresponding N3 tunnel towards the gNB, which maps the QoS Flow packets into the corresponding radio bearers to transfer the traffic to the UE.

[0022] FIGURE 5B illustrates a graphical representation of the traffic exchange among the different entities, including a Relay node 1, a Relay node 2, a donor node, and the Core network. UPF and rUE delivers IP packets to IP layer for routing. Each relay node (both the gNB part and the UE part) can be reached by IP.

[0023] This solution can re-use legacy gNB-implementation at the relay node. There is a direct path for IP connectivity among relay nodes, as the IP connectivity is terminated at a UPF co-located with the gNB part of the relay node which offers connectivity to other relay nodes. In other words, there is no need to reach the UPF donor for Xn between nodes on the same branch (i.e., associated to the same donor).

[0024] Tunneled PDU Session

[0025] FIGURE 6 illustrates a Tunneled PDU Session, which was discussed as option 2b in TR 38.874, vl6.0.0. The principle is that IP connectivity of the relay node is realized by an IP PDU session, which is tunneled in its upstream nodes’ IP PDU sessions. For this approach, there is no need for an additional 3GPP component (UPFs) at each relay node. Rather, UPFs are located in a “centralized “place, instead of being distributed to each relay node.

[0026] This approach results in a tunnel -over-tunnel problem, where the number of tunneled sessions depends on the number of hops. Additionally to reach relay node (either rUE or gNB), the IP packets need to first reach the relevant UPF in the core. This implies that there is an inefficient traffic route for Xn interface among nodes associated to the same branch and donor. For example, for two adjacent child-parent nodes, Xn traffic needs to reach UPF donor and other UPFs and then back to the destination relay node. This further means that it is not possible to support distributed user plane topologies for end-users, if needed (i.e., no support for local breakout at relay nodes).

[0027] Certain problems exist, however. For example, the previously discussed relay architecture solutions (e.g., LTE Relay Alt. 3 architecture, serialized PDU session, IAB and solution) are too costly to run and to implement or suffer from some technical shortcomings (e.g., tunneled PDU session): • For the LTE Relay Alt. 3, the DeNB needs to integrate functionalities of SGW7PGW. This means that the DeNB is a different node than a legacy eNB. The consequence is that the operator, in addition to deploying RNs, must deploy new network nodes (DeNBs) or to change the functionality of already deployed eNB (to be updated to become DeNB), which comes with extra costs.

[0028] • The IAB solution relies on CU-DU split (i.e., a form of higher layer split). With the possibility to introduce lower layer split in the 6G, the need to have such a higher layer split is questionable. More importantly, the IAB solution requires implementation of the IAB-MT with the new Backhaul Adaptation Protocol (BAP) layer (i.e., it is not possible to re-use an off-the-shelf UE chipset implementation). The additional implementation cost has shown to be significant to hinder IAB commercialization.

[0029] • For the serialized PDU session, the relay node needs to have a core network entity (UPF) on board, which means more processing needs at the relay node. Potentially, one could extend the approach used in LTE Relay Alt. 3 architecture where the gNB at the relay node integrates the functionalities of UPF. In the 5G system, it would mean that the relay node establishes a PDU Session without a N3 tunnel towards the parent node. This would involve the same issue discussed above for LTE Relay that an operator needs to change already deployed gNB to be updated to become “gNB integrating UPF functionalities.” Overall, such solutions have side effects of being complicated and may be costly to run for a relay node and a donor node.

[0030] • For tunneled PDU session, there is an overhead associated with tunnel-over- tunnel, which scales with number of hops. Additionally, there is no direct IP connectivity to each relay node (i.e., the Xn traffic between two relay nodes need to first via the UPFs in the core network).

[0031] On the other hand, there are still business opportunities in infrastructure-based relay solutions in the case of flexible deployment scenarios for increased coverage such as, for example, for public safety and / or defense. As such, there is a need to find an alternative solution that is easy to implement and deploy. SUMMARY

[0032] To address the foregoing problems with existing solutions, disclosed is systems and methods for providing an architecture for a multi -hop relay network. For example, methods and systems are provided for selecting a type of PDU Session to establish for a rUE depending on whether it connects to a relay node or to a donor node.

[0033] According to certain embodiments, a method by a relay node of a relay network includes establishing a connection with a core network based on whether the relay node is at a first hop of the relay network. Specifically, when the relay node is not at the first hop of a relay network, the connection includes a DRB without a user plane tunnel. Alternatively, when the relay node is at the first hop of a relay network, the connection includes a DRB and a user plane tunnel.

[0034] According to certain embodiments, a relay node of a relay network is adapted to establish a connection with a core network based on whether the relay node is at a first hop of the relay network. Specifically, when the relay node is not at the first hop of a relay network, the connection includes a DRB without a user plane tunnel. Alternatively, when the relay node is at the first hop of a relay network, the connection includes a DRB and a user plane tunnel.

[0035] According to certain embodiments, a method by a core network node of a relay network includes establishing a connection for a relay node based on whether the relay node is at a first hop of the relay network. Specifically, when the relay node is not at a first hop of a relay network, the connection includes a DRB without a user plane tunnel. Alternatively, when the relay node is at the first hop of a relay network, the connection includes a DRB and a user plane tunnel.

[0036] According to certain embodiments, a core network node of a relay network is adapted to establish a connection for a relay node based on whether the relay node is at a first hop of the relay network. Specifically, when the relay node is not at a first hop of a relay network, the connection includes a DRB without a user plane tunnel. Alternatively, when the relay node is at the first hop of a relay network, the connection includes a DRB and a user plane tunnel.

[0037] Certain embodiments of the present disclosure may provide one or more technical advantages. For example, certain embodiments may provide a technical advantage of supporting a relaying architecture where there is no need to have core network functions (e.g., UPF) at relay nodes As another example, certain embodiments may provide a technical advantage of not requiring changes to already deployed gNBs. Accordingly, an already deployed gNB may start acting as a donor gNB and support relay nodes without the need of being updated with extra functionalities. Thus certain embodiments may be expected to provide benefits in terms of lower costs to deploy relay solutions as it eases the cost at donor gNB side. Other advantages may be readily apparent to one having skill in the art. Certain embodiments may have none, some, or all of the recited advantages.

[0038] BRIEF DESCRIPTION OF THE DRAWINGS

[0039] For a more complete understanding of the disclosed embodiments and their features and advantages, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:

[0040] FIGURE 1 illustrates a user plane protocol stack for Alt. 3 of architecture A;

[0041] FIGURE 2 illustrates the IAB architecture, which includes an lAB-node using standalone (SA) mode with Next Generation Core (NGC);

[0042] FIGURE 3 illustrates the parent and child-node relationship for an lAB-node;

[0043] FIGURE 4 illustrates a Layer 3 user plane radio protocol stack;

[0044] FIGURES 5A-5B illustrate a serialized PDU session;

[0045] FIGURE 6 illustrates a Tunneled PDU Session;

[0046] FIGURE 7 illustrates a network relay with concatenation via IP routing between legacy PDU Session and PDU Session without N3 tunnel, according to certain embodiments;

[0047] FIGURES 8A-8B illustrate an example protocol stack and communication channel, respectively, according to certain embodiments;

[0048] FIGURE 9 illustrates an example communication system, according to certain embodiments;

[0049] FIGURE 10 illustrates an example UE, according to certain embodiments;

[0050] FIGURE 11 illustrates an example network node, according to certain embodiments;

[0051] FIGURE 12 illustrates a block diagram of a host, according to certain embodiments;

[0052] FIGURE 13 illustrates a virtualization environment in which functions implemented by some embodiments may be virtualized, according to certain embodiments;

[0053] FIGURE 14 illustrates a host communicating via a network node with a UE over a partially wireless connection, according to certain embodiments;

[0054] FIGURE 15 illustrates a method by a relay node of a relay network, according to certain embodiments; and

[0055] FIGURE 16 illustrates a method by a core network node of a relay network, according to certain embodiments. DETAILED DESCRIPTION

[0056] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.

[0057] As used herein, ‘node’ can be a network node or a UE. Examples of network nodes are NodeB, base station (BS), multi-standard radio (MSR) radio node such as MSR BS, eNodeB (eNB), gNodeB (gNB), Master eNB (MeNB), Secondary eNB (SeNB), integrated access backhaul (IAB) node, network controller, radio network controller (RNC), base station controller (BSC), relay, donor node controlling relay, base transceiver station (BTS), Centralized Unit (e.g., in a gNB), Distributed Unit (e.g., in a gNB), Baseband Unit, Centralized Baseband, C-RAN, access point (AP), transmission points, transmission nodes, Remote Radio Unit (RRU), Remote Radio Head (RRH), nodes in distributed antenna system (DAS), core network node (e.g., Mobile Switching Center (MSC), Mobility Management Entity (MME), etc.), Operations & Maintenance (O&M), Operations Support System (OSS), Self Organizing Network (SON), positioning node (e.g., Evolved-Serving Mobile Location Centre (E-SMLC)), etc.

[0058] Another example of a node is user equipment (UE), which is a non-limiting term and refers to any type of wireless device communicating with a network node and / or with another UE in a cellular or mobile communication system. Examples of UE are target device, device to device (D2D) UE, vehicular to vehicular (V2V), machine type UE, Machine Type Communication (MTC) UE or UE capable of machine to machine (M2M) communication, Personal Digital Assistant (PDA), Tablet, mobile terminals, smart phone, laptop embedded equipment (LEE), laptop mounted equipment (LME), Unified Serial Bus (USB) dongles, etc.

[0059] The term radio access technology (RAT), may refer to any RAT such as, for example, Universal Terrestrial Radio Access Network (UTRA), Evolved Universal Terrestrial Radio Access Network (E-UTRA), narrow band internet of things (NB-IoT), WiFi, Bluetooth, next generation RAT, NR, 4G, 5G, etc. Any of the equipment denoted by the terms node, network node or radio network node may be capable of supporting a single or multiple RATs.

[0060] The term signal or radio signal used herein can be any physical signal or physical channel. Examples of downlink physical signals are reference signal (RS) such as Primary Synchronization Signal (PSS), Secondary Synchronization Signal (SSS), Channel State Information-Reference Signal (CSLRS), Demodulation Reference Signal (DMRS) in SS / PBCH block (SSB), discovery reference signal (DRS), Cell-Specific Reference Signal (CRS), Positioning Reference Signal (PRS), etc. Examples of uplink physical signals are reference signal such as SRS, DMRS, etc. The term physical channel refers to any channel carrying higher layer information (e.g., data, control, etc.). Examples of physical channels are Physical Broadcast Channel (PBCH), Narrowband-PBCH (NPBCH), Physical Downlink Control Channel (PDCCH), Physical Downlink Shared Channel (PDSCH), Physical Uplink Shared Channel (PUSCH), Physical Uplink Control Channel (PUCCH), short Physical Uplink Control Channel (sPUCCH), short Physical Downlink Shared Channel (sPDSCH), short Physical Uplink Shared Channel (sPUSCH), MTC PDCCH (MPDCCH), Narrowband PDCCH (NPDCCH), Narrowband PDSCH (NPDSCH), Enhanced PDCCH (E-PDCCH), Narrowband PUSCH (NPUSCH), etc.

[0061] According to certain embodiments, systems and methods are provided for selecting a type of communication session such as, for example, a PDU Session, to establish for a rUE depending on whether the rUE connects to a relay node or to a donor node. In a particular embodiment, for example, when a rUE of a relay node establishes connectivity to a mobile network and connects to the gNB of a relay node (i.e., the relay node is not at the first hop of a relay network), the rUE establishes a PDU Session with only a DRB (or more DRBs) component terminated at the gNB and backhaul traffic is carried on this DRB to the gNB and routed by IP in the gNB. Alternatively, when a rUE of a relay node establishes connectivity to a mobile network and connects to the donor gNB (i.e., the relay node is at the first hop of a relay network), the rUE establishes a legacy PDU Session with the legacy PDU Session being terminated at a UPF.

[0062] FIGURE 7 illustrates a network relay 100 with concatenation via IP routing between legacy PDU Session 105 and PDU Session without N3 tunnel 110, according to certain embodiments.

[0063] As used herein, a relay node 115 is composed of rUE 120 with a UE as a baseline and gNB as a baseline. The relaying of traffic from / to relay nodes is achieved by concatenating a legacy PDU Session (composed of both DRB and N3 tunnel) with a PDU Session without an N3 tunnel (composed of only DRB), as shown in FIGURE 7.

[0064] As used herein, the donor node (donor gNB 125) is a classical network node with wired connection, and handling user plane traffic of rUE 120 as a legacy gNB (i.e., mapping traffic from / to N3 tunnel). On the other hand, the gNB of a relay node has additional functionalities that allow the gNB to directly terminate user plane traffic.

[0065] It is noted that, as used herein, rUE does not refer to a mobile phone, but rather a chipset implementation of a legacy UE with potentially external antennas and power amplifiers. gNB here refers to a legacy gNB implementation but with necessary modifications to support the functionalities described herein when it comes to relay node.

[0066] According to certain embodiments, an architecture is proposed that uses IP routing at relay nodes and includes the relay node obtaining an IP address with connectivity on the transport network level. A legacy PDU Session is used to obtain connecting towards the core network (where there are AMF / UPF / etc. associated to end-user UEs connected via relay nodes) via the donor gNB.

[0067] FIGURES 8A and 8B illustrate an example protocol stack 200 and communication channel 205, respectively, according to certain embodiments. Specifically, FIGURES 8A- 8B demonstrate how backhauling traffic of an rUE of a relay node reaches the core network using concatenation of IP transport solutions and legacy PDU session.

[0068] For example, as depicted, the traffic of end UE 210 is IP -based, where the traffic of the end UE reaches gNB2 215 of relay node-2 220 and it is carried over N2 / N3 interfaces towards the core network (AMF / UPF associated to the end UE). Traffic of N2 / N3 interfaces of via gNB2 215 of relay node-2 220 is routed via rUE2 225, gNBl 230, rUEl 235, gNB donor 240, and UPF donor 245. Backhauling connectivity for rUE2 225 is terminated directly at gNBl 230, which may include a gNB extended with extra functionalities. Instead, backhauling connectivity for rUEl 235 is terminated at UPF donor 245 as in a legacy PDU Session.

[0069] According to certain embodiments, systems and methods are disclosed for selecting a type of PDU Session to establish for a rUE depending on whether it connects to a relay node or to a donor node.

[0070] In more detail, taking gNBl 230 as an example, the gNBl 230of a relay nodel 250 behaves as follows:

[0071] 1. If gNBl 230 receives the IP packet from rUE2 225 via the wireless / air interface, the gNBl 230 delivers the IP packet to the upper layer to perform IP routing (instead of providing the packets to GTP-U layer / mapping to N3 tunnel).

[0072] 2. If gNBl 230 receives the IP packet from the upper layer IP routing protocol (instead of receiving user plane packets from GTP-U layer / N3 tunnel), the gNBl 230 delivers the IP packet to the lower layer for transmission via the wireless / air interface.

[0073] Setup of a PDU Session without N3 tunnel When a rUE establishes connectivity towards the mobile network, the network decides whether to establish a PDU Session without N3 tunnel or a legacy PDU Session.

[0074] In one embodiment, the rUE requests to establish its PDU Session using previously disclosed methods and solution such as, for example, via NAS signalling. In this case, it is the core network 255 (e.g., SMF) that decides whether to establish a PDU Session without N3 tunnel or a legacy PDU Session. Examples of how the SMF decides this are:

[0075] • Based on UE location information included in the PDU Session establishment request, e.g., cell-IDs or gNB-IDs'. The SMF can be configured to establish a PDU Session without N3 tunnel for certain set of cell-IDs or gNB-IDs. For other cases (rUE connected via a donor gNB), SMF establishes a legacy PDU Session.

[0076] • Based on information provided by the other network entity. In one example, the gNB of a relay node is configured to include a flag “relay node” when it sends the PDU Session establishment request to the AMF, and the AMF provides such information to SMF. For other cases (rUE connected via a donor gNB), donor gNB is not configured to include the “relay node” flag. Thus, SMF will establish a legacy PDU Session. In another example, the AMF is aware whether the gNB to which the PDU Session establishment request is associated is a “relay node”, e.g., as part of the information provided by the gNB when it registers to AMF and informs accordingly the SMF during the PDU Session establishment.

[0077] In another embodiment, the establishment of the PDU Session without N3 tunnel is done without involvement of the core network 255 and it is handled directly by the gNB of the relay node.

[0078] In one example, it is not a “PDU Session”, but something related to a new RAN- level functionality. For instance, this new functionality can be called something like “Connectivity request for backhauling” and is a new functionality on the RRC layer. It can also be called “PDU Session without N3 tunnel”. An example of this embodiment includes the following steps:

[0079] • The gNB of a relay node is extended with the “Connectivity request for backhauling” functionality. To support this functionality, it is configured with information on how to handle user plane for this session (e.g., how to map incoming IP packets to QoS Flows, policies related to the traffic, and so on).

[0080] • When the rUE connects to the gNB of a relay node, the rUE uses the “connectivity request for backhauling” functionality when the rUE wants to establish user plane for backhauling (instead of initiating the legacy establishment of a PDU Session via NAS signalling). This can be achieved by an explicit gNB configuration to the said the rUE, which implies that the gNB needs to be aware that it is an “rUE” which is connected to it, e.g., indicated by the rUE in its initial connection request message. This can also be achieved by an explicit rUE request. This implies that this gNB broadcasts information indicating that the rUE is a relay node and so can accept such request. Note that the gNB of a donor node is not configured with the functionality related to a connectivity request for backhauling.

[0081] • The rUE uses the new functionality “Session request for backhauling” to connect towards the respective gNB of a relay node.

[0082] In another example of the above embodiment without core network, it is a normal PDU Session from both rUE and core network point of view. However, the gNB at the relay node performs necessary proxy-like functions. The gNB at the relay node also needs to be aware that it is a request of a rUE at the relay node but not a legacy UE.

[0083] Upstream Traffic Mapping at gNB of a Relay Node

[0084] After the gNB at the relay node receives PDUs from the air interface using Uu interface, the gNB directly delivers the PDUs to the IP layer at the relay node to perform routing instead of wrapping it in an N3 tunnel (as in the legacy).

[0085] Various conditions relating to which PDUs are to be delivered to the IP layers are possible and described in more detail below. Likewise, various methods may be used to enable a gNB of a relay node to be aware of these conditions.

[0086] For example, according to a particular embodiment, only PDUs received from a specific DRB / QoS Flow of a PDU Session are delivered to the IP layer. When establishing the PDU Session for a relay UE (e.g., rUE2), its upstream gNB (e.g., gNBl) is configured by SMF that (a certain) QoS Flow (mapped to specific DRB by the gNB) from rUE2 be given to IP. It could be an indication like “no N3 tunnel for this QoS Flow,” for example. Or, the gNB may be pre-configured with such information if it is the gNB which directly handles the establishment of the DRBs used for backhauling. In a further particular embodiment, a specific QoS Flow Identifier (QFI) is introduced (e.g., standardized) which is used to identify backhauling traffic that a gNB delivers to the IP layer. In another particular embodiment, a new Boolean parameter (e.g., “no N3 tunnel for this QoS Flow”) is introduced to set of parameters associated to a QoS Flow.

[0087] As another example, according to a particular embodiment, a field in the SDAP header is used to indicate that the PDU is to be delivered to the IP layer. When establishing the PDU Session, rUE2 is configured to populate a field in SDAP header to indicate “IP relay”, gNBl checks this field and understands that the packet should be given to IP. The rUE can be configured in different ways. In a particular embodiment, for example, the standard defines that a UE adds the SDAP header indication for the traffic belonging to a certain type of PDU Session (e.g., No N3 termination PDU Session type) or to a certain QFI or to QFIs that include the parameter “no N3 tunnel for this QoS Flow.” In another particular embodiment, the gNB configures the rUE to add the indication “IP relay” in SDAP header for traffic associated to relevant QoS Flows / DRBs.

[0088] For rUEs (which co-locate with a gNB at a relay node), after receiving the routed IP packets from upper layers, the rUE marks the PDUs according to the specific conditions so that further upstream gNBs can route the PDUs correspondingly. In a particular embodiment, rUEs put received routed IP packets into the specific DRBs. In another embodiment, rUEs mark the filed in the SDAP header of the received routed IP packets.

[0089] Downstream Traffic Mapping at gNB

[0090] After the relay node receives IP packets from the network interface, the packets that are not destined to the relay node (e.g., the destination address is not the IP address of the gNB or the rUE of the relay node) are provided to the gNB, which wraps them as a PDUs for transmission on the Uu interface. The gNB is extended with functionalities of mapping the IP packets to relevant QoS Flows / DRBs to use for transmission. According to previous techniques, the gNB receives packets over N3 tunnel, and the packets are already mapped to QoS Flows. The gNB retrieves the IP packet from the N3 tunnel (e.g., removing GTP-U header, etc.) and continues with the processing of RAN stack (e.g., mapping to DRB, ciphering, etc.).

[0091] According to various embodiments, the gNB may be made aware of conditions for mapping the IP packets to be transmitted on the Uu interface as follows: 1. In a particular embodiment, the SMF provides the gNB of a relay node with QoS rules or Packet Detection Rules to determine mapping between downlink User Plane traffic and QoS Flows. Rules can be provided (e.g., at PDU Session Establishment or Modification)that indicate that mapping is performed based on source IP address, destination IP address, 3 -tuple, 5- tuple, etc.

[0092] 2. In another particular embodiment, the gNB of a relay node performs a sort of “reflective mapping” based on the traffic received in uplink from the rUEs. In this case, the gNB monitors the PDUs that are received from an rUE and delivered to the IP layer. In particular, the monitoring consists of understanding which traffic (based on source IP address, destination IP address, 3-tuple, 5-tuple, etc.) is mapped to a certain QoS Flow. For example, the gNB may know that an IP packet from source IP address X.X.X.X is mapped to QoS Flow Y. In downlink, the gNB performs the reflecting mapping, for example, by mapping IP packets with destination IP address X.X.X.X to QoS Flow Y. In various particular embodiments, the gNB may be aware that it has to perform “reflective mapping” for certain traffic in uplink based on one or more of: a. The standard specifies that the gNB is to perform “reflecting mapping” for certain QFIs / 5QIs. b. Information is provided by, for example, the SMF indicates that the gNB is to perform “reflective mapping.” If SMF provides the information that a QFI is marked with “no N3 tunnel for this QoS Flow”, gNB performs “reflecting mapping” for the uplink traffic of that QoS Flow. c. The gNB determines to perform reflective mapping based on marking on PDUs received in uplink. For example, the gNB performs “reflecting mapping” for PDUs where SDAP header includes the indication of “IP relay”.

[0093] FIGURE 9 shows an example of a communication system 300 in accordance with some embodiments. In the example, the communication system 300 includes a telecommunication network 302 that includes an access network 304, such as a radio access network (RAN), and a core network 306, which includes one or more core network nodes 308. The access network 304 includes one or more access network nodes, such as network nodes 310a and 310b (one or more of which may be generally referred to as network nodes 310), or any other similar 3rdGeneration Partnership Project (3GPP) access node or non- 3GPP access point. The network nodes 310 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 312a, 312b, 312c, and 312d (one or more of which may be generally referred to as UEs 312) to the core network 306 over one or more wireless connections.

[0094] Example wireless communications over a wireless connection include transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 300 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that may facilitate or participate in the communication of data and / or signals whether via wired or wireless connections. The communication system 300 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0095] The UEs 312 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and / or operable to communicate wirelessly with the network nodes 310 and other communication devices. Similarly, the network nodes 310 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 312 and / or with other network nodes or equipment in the telecommunication network 302 to enable and / or provide network access, such as wireless network access, and / or to perform other functions, such as administration in the telecommunication network 302.

[0096] In the depicted example, the core network 306 connects the network nodes 310 to one or more hosts, such as host 316. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 306 includes one more core network nodes (e.g., core network node 308) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and / or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 308. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-concealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and / or a User Plane Function (UPF).

[0097] The host 316 may be under the ownership or control of a service provider other than an operator or provider of the access network 304 and / or the telecommunication network 302, and may be operated by the service provider or on behalf of the service provider. The host 316 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio / video content, data collection services such as retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.

[0098] As a whole, the communication system 300 of FIGURE 9 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and / or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and / or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and / or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox.

[0099] In some examples, the telecommunication network 302 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 302 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 302. For example, the telecommunications network 302 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and / or Massive Machine Type Communication (mMTC)ZMassive loT services to yet further UEs. In some examples, the UEs 312 are configured to transmit and / or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 304 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 304. Additionally, a UE may be configured for operating in single- or multi -RAT or multi -standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN-DC).

[0100] In the example, the hub 314 communicates with the access network 304 to facilitate indirect communication between one or more UEs (e.g., UE 312c and / or 312d) and network nodes (e.g., network node 310b). In some examples, the hub 314 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 314 may be a broadband router enabling access to the core network 306 for the UEs. As another example, the hub 314 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 310, or by executable code, script, process, or other instructions in the hub 314. As another example, the hub 314 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 314 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 314 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 314 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 314 acts as a proxy server or orchestrator for the UEs, in particular in if one or more of the UEs are low energy loT devices.

[0101] The hub 314 may have a constant / persistent or intermittent connection to the network node 310b. The hub 314 may also allow for a different communication scheme and / or schedule between the hub 314 and UEs (e.g., UE 312c and / or 312d), and between the hub 314 and the core network 306. In other examples, the hub 314 is connected to the core network 306 and / or one or more UEs via a wired connection. Moreover, the hub 314 may be configured to connect to an M2M service provider over the access network 304 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 310 while still connected via the hub 314 via a wired or wireless connection. In some embodiments, the hub 314 may be a dedicated hub - that is, a hub whose primary function is to route communications to / from the UEs from / to the network node 310b. In other embodiments, the hub 314 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 310b, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0102] FIGURE 10 shows a UE 400 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged and / or operable to communicate wirelessly with network nodes and / or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless cameras, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop- embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehicle-mounted or vehicle embedded / integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-IoT) UE, a machine type communication (MTC) UE, and / or an enhanced MTC (eMTC) UE.

[0103] A UE may support device-to-device (D2D) communication, for example by implementing a 3 GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and / or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).

[0104] The UE 400 includes processing circuitry 402 that is operatively coupled via a bus 404 to an input / output interface 406, a power source 408, a memory 410, a communication interface 412, and / or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in FIGURE 10. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0105] The processing circuitry 402 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 410. The processing circuitry 402 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 402 may include multiple central processing units (CPUs).

[0106] In the example, the input / output interface 406 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and / or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 400. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.

[0107] In some embodiments, the power source 408 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 408 may further include power circuitry for delivering power from the power source 408 itself, and / or an external power source, to the various parts of the UE 400 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 408. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 408 to make the power suitable for the respective components of the UE 400 to which power is supplied.

[0108] The memory 410 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 410 includes one or more application programs 414, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 416. The memory 410 may store, for use by the UE 400, any of a variety of various operating systems or combinations of operating systems.

[0109] The memory 410 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and / or ISIM, other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’ The memory 410 may allow the UE 400 to access instructions, application programs and the like, stored on transitory or non- transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory 410, which may be or comprise a device-readable storage medium.

[0110] The processing circuitry 402 may be configured to communicate with an access network or other network using the communication interface 412. The communication interface 412 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 422. The communication interface 412 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network). Each transceiver may include a transmitter 418 and / or a receiver 420 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 418 and receiver 420 may be coupled to one or more antennas (e.g., antenna 422) and may share circuit components, software or firmware, or alternatively be implemented separately.

[0111] In the illustrated embodiment, communication functions of the communication interface 412 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented in according to one or more communication protocols and / or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol / internet protocol (TCP / IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

[0112] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 412, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient).

[0113] As another example, a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or to a robotic arm performing a medical procedure according to the received input.

[0114] A UE, when in the form of an Internet of Things (loT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare. Non-limiting examples of such an loT device are a device which is or which is embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door / window sensor, a flood / moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head -mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an loT device comprises circuitry and / or software in dependence of the intended application of the loT device in addition to other components as described in relation to the UE 400 shown in FIGURE 10.

[0115] As yet another specific example, in an loT scenario, a UE may represent a machine or other device that performs monitoring and / or measurements, and transmits the results of such monitoring and / or measurements to another UE and / or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and / or reporting on its operational status or other functions associated with its operation.

[0116] In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’ s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone’s speed. The first and / or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.

[0117] FIGURE 11 shows a network node 500 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged and / or operable to communicate directly or indirectly with a UE and / or with other network nodes or equipment, in a telecommunication network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)).

[0118] Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units and / or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).

[0119] Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi- cell / multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and / or Minimization of Drive Tests (MDTs).

[0120] The network node 500 includes a processing circuitry 502, a memory 504, a communication interface 506, and a power source 508. The network node 500 may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 500 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node 500 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 504 for different RATs) and some components may be reused (e.g., a same antenna 510 may be shared by different RATs). The network node 500 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 500, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 500.

[0121] The processing circuitry 502 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and / or encoded logic operable to provide, either alone or in conjunction with other network node 500 components, such as the memory 504, to provide network node 500 functionality.

[0122] In some embodiments, the processing circuitry 502 includes a system on a chip (SOC). In some embodiments, the processing circuitry 502 includes one or more of radio frequency (RF) transceiver circuitry 512 and baseband processing circuitry 514. In some embodiments, the radio frequency (RF) transceiver circuitry 512 and the baseband processing circuitry 514 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 512 and baseband processing circuitry 514 may be on the same chip or set of chips, boards, or units.

[0123] The memory 504 may comprise any form of volatile or non-volatile computer- readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and / or any other volatile or non-volatile, non-transitory device- readable and / or computer-executable memory devices that store information, data, and / or instructions that may be used by the processing circuitry 502. The memory 504 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and / or other instructions capable of being executed by the processing circuitry 502 and utilized by the network node 500. The memory 504 may be used to store any calculations made by the processing circuitry 502 and / or any data received via the communication interface 506. In some embodiments, the processing circuitry 502 and memory 504 is integrated.

[0124] The communication interface 506 is used in wired or wireless communication of signaling and / or data between a network node, access network, and / or UE. As illustrated, the communication interface 506 comprises port(s) / terminal(s) 516 to send and receive data, for example to and from a network over a wired connection. The communication interface 506 also includes radio front-end circuitry 518 that may be coupled to, or in certain embodiments a part of, the antenna 510. Radio front-end circuitry 518 comprises filters 520 and amplifiers 522. The radio front-end circuitry 518 may be connected to an antenna 510 and processing circuitry 502. The radio front-end circuitry may be configured to condition signals communicated between antenna 510 and processing circuitry 502. The radio front-end circuitry 518 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 518 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 520 and / or amplifiers 522. The radio signal may then be transmitted via the antenna 510. Similarly, when receiving data, the antenna 510 may collect radio signals which are then converted into digital data by the radio front-end circuitry 518. The digital data may be passed to the processing circuitry 502. In other embodiments, the communication interface may comprise different components and / or different combinations of components.

[0125] In certain alternative embodiments, the network node 500 does not include separate radio front-end circuitry 518, instead, the processing circuitry 502 includes radio front-end circuitry and is connected to the antenna 510. Similarly, in some embodiments, all or some of the RF transceiver circuitry 512 is part of the communication interface 506. In still other embodiments, the communication interface 506 includes one or more ports or terminals 516, the radio front-end circuitry 518, and the RF transceiver circuitry 512, as part of a radio unit (not shown), and the communication interface 506 communicates with the baseband processing circuitry 514, which is part of a digital unit (not shown).

[0126] The antenna 510 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna 510 may be coupled to the radio front-end circuitry 518 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 510 is separate from the network node 500 and connectable to the network node 500 through an interface or port.

[0127] The antenna 510, communication interface 506, and / or the processing circuitry 502 may be configured to perform any receiving operations and / or certain obtaining operations described herein as being performed by the network node. Any information, data and / or signals may be received from a UE, another network node and / or any other network equipment. Similarly, the antenna 510, the communication interface 506, and / or the processing circuitry 502 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and / or signals may be transmitted to a UE, another network node and / or any other network equipment.

[0128] The power source 508 provides power to the various components of network node 500 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 508 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 500 with power for performing the functionality described herein. For example, the network node 500 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 508. As a further example, the power source 508 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.

[0129] Embodiments of the network node 500 may include additional components beyond those shown in FIGURE 11 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and / or any functionality necessary to support the subject matter described herein. For example, the network node 500 may include user interface equipment to allow input of information into the network node 500 and to allow output of information from the network node 500. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 500.

[0130] FIGURE 12 is a block diagram of a host 600, which may be an embodiment of the host 316 of FIGURE 9, in accordance with various aspects described herein. As used herein, the host 600 may be or comprise various combinations hardware and / or software, including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host 600 may provide one or more services to one or more UEs.

[0131] The host 600 includes processing circuitry 602 that is operatively coupled via a bus 604 to an input / output interface 606, a network interface 608, a power source 610, and a memory 612. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figures 4 and 5, such that the descriptions thereof are generally applicable to the corresponding components of host 600. The memory 612 may include one or more computer programs including one or more host application programs 614 and data 616, which may include user data, e.g., data generated by a UE for the host 600 or data generated by the host 600 for a UE. Embodiments of the host 600 may utilize only a subset or all of the components shown. The host application programs 614 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAC, Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, heads-up display systems). The host application programs 614 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host 600 may select and / or indicate a different host for over-the-top services for a UE. The host application programs 614 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), etc.

[0132] FIGURE 13 is a block diagram illustrating a virtualization environment 700 in which functions implemented by some embodiments may be virtualized.

[0133] In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments 700 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host. Further, in embodiments in which the virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized.

[0134] Applications 702 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment Q400 to implement some of the features, functions, and / or benefits of some of the embodiments disclosed herein. Hardware 704 includes processing circuitry, memory that stores software and / or instructions executable by hardware processing circuitry, and / or other hardware devices as described herein, such as a network interface, input / output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 706 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 708a and 708b (one or more of which may be generally referred to as VMs 708), and / or perform any of the functions, features and / or benefits described in relation with some embodiments described herein. The virtualization layer 706 may present a virtual operating platform that appears like networking hardware to the VMs 708.

[0135] The VMs 708 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 706. Different embodiments of the instance of a virtual appliance 702 may be implemented on one or more of VMs 708, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment.

[0136] In the context of NFV, a VM 708 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 708, and that part of hardware 704 that executes that VM, be it hardware dedicated to that VM and / or hardware shared by that VM with others of the VMs, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs 708 on top of the hardware 704 and corresponds to the application 702.

[0137] Hardware 704 may be implemented in a standalone network node with generic or specific components. Hardware 704 may implement some functions via virtualization. Alternatively, hardware 704 may be part of a larger cluster of hardware (e.g. such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 710, which, among others, oversees lifecycle management of applications 702. In some embodiments, hardware 704 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station. In some embodiments, some signaling can be provided with the use of a control system 712 which may alternatively be used for communication between hardware nodes and radio units.

[0138] FIGURE 14 shows a communication diagram of a host 802 communicating via a network node 804 with a UE 806 over a partially wireless connection in accordance with some embodiments.

[0139] Example implementations, in accordance with various embodiments, of the UE (such as a UE 312a of FIGURE 9 and / or UE 400 of FIGURE 10), network node (such as network node 310a of FIGURE 9 and / or network node 500 of FIGURE 11), and host (such as host 316 of FIGURE 9 and / or host 600 of FIGURE 12) discussed in the preceding paragraphs will now be described with reference to FIGURE 14.

[0140] Like host 600, embodiments of host 802 include hardware, such as a communication interface, processing circuitry, and memory. The host 802 also includes software, which is stored in or accessible by the host 802 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the UE 806 connecting via an over-the-top (OTT) connection 850 extending between the UE 806 and host 802. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 850.

[0141] The network node 804 includes hardware enabling it to communicate with the host 802 and UE 806. The connection 860 may be direct or pass through a core network (like core network 306 of FIGURE 9) and / or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet.

[0142] The UE 806 includes hardware and software, which is stored in or accessible by UE 806 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via UE 806 with the support of the host 802. In the host 802, an executing host application may communicate with the executing client application via the OTT connection 850 terminating at the UE 806 and host 802. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection 850 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 850. The OTT connection 850 may extend via a connection 860 between the host 802 and the network node 804 and via a wireless connection 870 between the network node 804 and the UE 806 to provide the connection between the host 802 and the UE 806. The connection 860 and wireless connection 870, over which the OTT connection 850 may be provided, have been drawn abstractly to illustrate the communication between the host 802 and the UE 806 via the network node 804, without explicit reference to any intermediary devices and the precise routing of messages via these devices.

[0143] As an example of transmitting data via the OTT connection 850, in step 808, the host 802 provides user data, which may be performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE 806. In other embodiments, the user data is associated with a UE 806 that shares data with the host 802 without explicit human interaction. In step 810, the host 802 initiates a transmission carrying the user data towards the UE 806. The host 802 may initiate the transmission responsive to a request transmitted by the UE 806. The request may be caused by human interaction with the UE 806 or by operation of the client application executing on the UE 806. The transmission may pass via the network node 804, in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 812, the network node 804 transmits to the UE 806 the user data that was carried in the transmission that the host 802 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 814, the UE 806 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 806 associated with the host application executed by the host 802.

[0144] In some examples, the UE 806 executes a client application which provides user data to the host 802. The user data may be provided in reaction or response to the data received from the host 802. Accordingly, in step 816, the UE 806 may provide user data, which may be performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input / output interface of the UE 806. Regardless of the specific manner in which the user data was provided, the UE 806 initiates, in step 818, transmission of the user data towards the host 802 via the network node 804. In step 820, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 804 receives user data from the UE 806 and initiates transmission of the received user data towards the host 802. In step 822, the host 802 receives the user data carried in the transmission initiated by the UE 806. One or more of the various embodiments improve the performance of OTT services provided to the UE 806 using the OTT connection 850, in which the wireless connection 870 forms the last segment. More precisely, the teachings of these embodiments may improve one or more of, for example, data rate, latency, and / or power consumption and, thereby, provide benefits such as, for example, reduced user waiting time, relaxed restriction on file size, improved content resolution, better responsiveness, and / or extended battery lifetime.

[0145] In an example scenario, factory status information may be collected and analyzed by the host 802. As another example, the host 802 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 802 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host 802 may store surveillance video uploaded by a UE. As another example, the host 802 may store or control access to media content such as video, audio, VR or AR which it can broadcast, multicast or unicast to UEs. As other examples, the host 802 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing and / or transmitting data.

[0146] In some examples, a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 850 between the host 802 and UE 806, in response to variations in the measurement results. The measurement procedure and / or the network functionality for reconfiguring the OTT connection may be implemented in software and hardware of the host 802 and / or UE 806. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 850 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 850 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node 804. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency and the like, by the host 802. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 850 while monitoring propagation times, errors, etc.

[0147] FIGURE 15 illustrates an example method 700 by a relay node of a relay network, according to certain embodiments. In the illustrated embodiment, the method includes the relay node establishing, at step 702, a connection with a core network based on whether the relay node is at a first hop of the relay network. Specifically, when the relay node is not at the first hop of a relay network, the connection includes a DRB without a user plane tunnel. Alternatively, when the relay node is at the first hop of a relay network, the connection includes a DRB and a user plane tunnel.

[0148] In a particular embodiment, the relay node is at the first hop of the relay network when the relay node communicates with the core network via a donor node. Or, the relay node is not at the first hop of the relay network when the relay node communicates with the core network via another relay node.

[0149] In a particular embodiment, the relay node comprises a gNB component and a rUE, component. The relay node is at the first hop of the relay network when the connection with the core network is between the rUE component of the relay node and a donor node. Or the relay node is not at the first hop of the relay network when the connection with the core network is between the rUE component of the relay node and another gNB component of another relay node.

[0150] In a particular embodiment, when establishing the connection with the core network, the relay node transmits a user plane connectivity request to the core network and receives a user plane connectivity response from the core network.

[0151] In a further particular embodiment, the user plane connectivity request that is transmitted to the core network includes an indication that the relay node is at the first hop of the relay network or an indication that the relay node is not at the first hop of the relay network.

[0152] In a further particular embodiment, the user plane connectivity request that is transmitted to the core network includes an indication that the connection is to comprise the DRB without a user plane tunnel or an indication that the connection is to comprise the DRB with the user plane tunnel. In a further particular embodiment, a gNB component of the relay node receives a request to establish user plane connectivity from a r-UE component of the relay node. The request to establish user plane connectivity includes an indication that the relay node is not at the first hop of the relay network or an indication that the connection is to comprise the DRB without a user plane tunnel.

[0153] In a further particular embodiment, the gNB component of the relay node receives a request to establish user plane connectivity from a r-UE component of the relay node. The request to establish user plane connectivity includes an indication that the connection is between the r-UE and another relay node.

[0154] In a further particular embodiment, the request to establish user plane connectivity comprises at least one of: a connectivity request for backhauling, a session request for backhauling, and a request for a session without the user plane tunnel.

[0155] In a further particular embodiment, the relay node receives information for handling user plane traffic, and the information includes at least one of: a mapping of at least one IP packet to at least one QoS flow, and at least one policy for forwarding the user plane traffic.

[0156] In a particular embodiment, the user plane connectivity request includes information for determining by the core network whether or not the relay node is at the first hop of the relay network. The user plane connectivity response includes: an indication that the connection comprises the DRB without a user plane tunnel, or an indication that the connection comprises the DRB with the user plane tunnel.

[0157] In a particular embodiment, the information includes at least one of: a cell identifier associated with a cell in which the relay node is located, a relay node identifier, an identifier associated with an Application Management Function, AMF, and a flag indicating that the relay node is a relay node.

[0158] In a further particular embodiment, the user plane connectivity request incudes a session establishment request.

[0159] In a particular embodiment, the user plane tunnel comprises a N3 tunnel.

[0160] FIGURE 16 illustrates an example method 800 by a core network node of a relay network, according to certain embodiments. In the illustrated embodiment, the method includes establishing a connection for a relay node, at step 802. Specifically, when the relay node is not at a first hop of a relay network, the connection includes a DRB without a user plane tunnel. Alternatively, when the relay node is at the first hop of a relay network, the connection includes a DRB and a user plane tunnel. In a particular embodiment, the relay node is at the first hop of the relay network when the connection with the core network is between the relay node and a donor node, or the relay node is not at the first hop of the relay network when the connection with the core network is between the relay node and another relay node.

[0161] In a particular embodiment, the relay node includes a gNB component and a rUE component. The relay node is at the first hop of the relay network when the connection with the core network is between the rUE component of the relay node and a donor node. Or the relay node is not at the first hop of the relay network when the connection with the core network is between the rUE component of the relay node and another gNB component of another relay node.

[0162] In a particular embodiment, when establishing the connection with the core network for the relay node, the core network node receives a user plane connectivity request from the relay node and transmits a user plane connectivity response to the relay node.

[0163] In a further particular embodiment, the user plane connectivity request that is received from the relay node includes an indication that the relay node is at the first hop of the relay network or an indication that the relay node is not at the first hop of the relay network.

[0164] In a further particular embodiment, the user plane connectivity request that is received from the relay node includes an indication that the connection is to comprise the DRB without a user plane tunnel or an indication that the connection is to comprise the DRB with the user plane tunnel.

[0165] In a particular embodiment, the user plane connectivity comprises at least one of a connectivity request for backhauling, a session request for backhauling, and a request for a session without the user plane tunnel.

[0166] In a particular embodiment, the core network node transmits information for handling user plane traffic to the relay node. The information includes at least one of a mapping of at least one IP packet to at least one QoS flow, and at least one policy for forwarding the user plane traffic.

[0167] In a further particular embodiment, the core network node determines, based on information in the user plane connectivity request, whether or not the relay node is at the first hop of the relay network.

[0168] In a further particular embodiment, the information in the user plane connectivity request comprises at least one of a cell identifier associated with a cell in which the relay node is located, a relay node identifier, an identifier associated with an AMF, and a flag indicating that the relay node is a relay node. In a further particular embodiment, the user plane connectivity request comprises a session establishment request.

[0169] In a particular embodiment, the user plane tunnel comprises a N3 tunnel.

[0170] Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and / or software needed to perform the tasks, features, functions and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and / or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and / or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.

[0171] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and / or by end users and a wireless network generally.

Claims

CLAIMS:

1. A method (700) by a relay node of a relay network, the method comprising: based on whether the relay node is at a first hop of the relay network, establishing (702) a connection with a core network for the relay node, wherein: when the relay node is not at the first hop of a relay network, the connection comprises a data radio bearer, DRB, without a user plane tunnel, or when the relay node is at the first hop of a relay network, the connection comprises a DRB and a user plane tunnel.

2. The method of Claim 1, wherein: the relay node is at the first hop of the relay network when the relay node communicates with the core network via a donor node, or the relay node is not at the first hop of the relay network when the relay node communicates with the core network via another relay node.

3. The method of any one of Claims 1 to 2, wherein the relay node comprises a gNodeB, gNB, component and a relay-User Equipment, rUE, component, and wherein: the relay node is at the first hop of the relay network when the connection with the core network is between the rUE component of the relay node and a donor node, or the relay node is not at the first hop of the relay network when the connection with the core network is between the rUE component of the relay node and another gNB component of another relay node.

4. The method of any one of Claims 1 to 3, wherein establishing the connection with the core network for the relay node comprises: transmitting, to the core network, a user plane connectivity request, and receiving, from the core network, a user plane connectivity response.

5. The method of Claim 4, wherein the user plane connectivity request that is transmitted to the core network comprises: an indication that the relay node is at the first hop of the relay network, or an indication that the relay node is not at the first hop of the relay network.

6. The method of Claim 4, wherein the user plane connectivity request that is transmitted to the core network comprises:an indication that the connection is to comprise the DRB without a user plane tunnel, or an indication that the connection is to comprise the DRB with the user plane tunnel.

7. The method of any one of Claims 5to 6, comprising: receiving, by a gNodeB, gNB, component of the relay node, a request to establish user plane connectivity from a relay -User Equipment, r-UE, component of the relay node, and wherein the request to establish user plane connectivity comprises: an indication that the relay node is not at the first hop of the relay network, or an indication that the connection is to comprise the DRB without a user plane tunnel.

8. The method of Claim 4, comprising: receiving, by a gNodeB, gNB, component of the relay node, a request to establish user plane connectivity from a relay -User Equipment, r-UE, component of the relay node, and wherein the request to establish user plane connectivity comprises an indication that the connection is between the r-UE and another relay node.

9. The method of Claim 8, wherein the request to establish user plane connectivity comprises at least one of: a connectivity request for backhauling, a session request for backhauling, and a request for a session without the user plane tunnel.

10. The method of any one of Claims 5 to 9, comprising receiving information for handling user plane traffic, wherein the information comprises at least one of: a mapping of at least one IP packet to at least one Quality of Service flow, and at least one policy for forwarding the user plane traffic.

11. The method of Claim 4, wherein: the user plane connectivity request comprises information for determining by the core network whether or not the relay node is at the first hop of the relay network, and the user plane connectivity response comprises:an indication that the connection comprises the DRB without a user plane tunnel, or an indication that the connection comprises the DRB with the user plane tunnel.

12. The method of Claim 11, wherein the information comprises at least one of: a cell identifier associated with a cell in which the relay node is located, a relay node identifier, an identifier associated with an Application Management Function, AMF, and a flag indicating that the relay node is a relay node.

13. The method of any one of Claims 11 to 12, wherein the user plane connectivity request comprises a session establishment request.

14. The method of any one of Claims 1 to 13, wherein the user plane tunnel comprises a N3 tunnel.

15. A method (800) by a core network node of a relay network, the method comprising: establishing (802) a connection for a relay node, and wherein: when the relay node is not at a first hop of a relay network, the connection comprises a data radio bearer, DRB, without a user plane tunnel, or when the relay node is at the first hop of a relay network, the connection comprises a DRB and a user plane tunnel.

16. The method of Claim 15, wherein: the relay node is at the first hop of the relay network when the connection with the core network is between the relay node and a donor node, or the relay node is not at the first hop of the relay network when the connection with the core network is between the relay node and another relay node.

17. The method of any one of Claims 15 to 16, wherein the relay node comprises a gNodeB, gNB, component and a relay-User Equipment, rUE, component, and wherein: the relay node is at the first hop of the relay network when the connection with the core network is between the rUE component of the relay node and a donor node, or the relay node is not at the first hop of the relay network when the connection with the core network is between the rUE component of the relay node and another gNB component of another relay node.

18. The method of any one of Claims 15 to 17, wherein establishing the connection with the core network for the relay node comprises: receiving, from the relay node, a user plane connectivity request, and transmitting, to the relay node, a user plane connectivity response.

19. The method of Claim 18, wherein the user plane connectivity request that is received from the relay node comprises: an indication that the relay node is at the first hop of the relay network, or an indication that the relay node is not at the first hop of the relay network.

20. The method of Claim 18, wherein the user plane connectivity request that is received from the relay node comprises: an indication that the connection is to comprise the DRB without a user plane tunnel, or an indication that the connection is to comprise the DRB with the user plane tunnel.

21. The method of any one of Claims 19 to 20, wherein the user plane connectivity comprises at least one of: a connectivity request for backhauling, a session request for backhauling, and a request for a session without the user plane tunnel.

22. The method of any one of Claims 20 to 21, comprising transmitting, to the relay node, information for handling user plane traffic, wherein the information comprises at least one of: a mapping of at least one IP packet to at least one Quality of Service flow, and at least one policy for forwarding the user plane traffic.

23. The method of Claim 18, comprising: determining, based on information in the user plane connectivity request, whether or not the relay node is at the first hop of the relay network.

24. The method of Claim 23, wherein the information in the user plane connectivity request comprises at least one of: a cell identifier associated with a cell in which the relay node is located, a relay node identifier, an identifier associated with an Application Management Function, AMF, and a flag indicating that the relay node is a relay node.

25. The method of any one of Claims 23 to 24, wherein the user plane connectivity request comprises a session establishment request.

26. The method of any one of Claims 15 to 25, wherein the user plane tunnel comprises a N3 tunnel.

27. A relay node of a relay network configured to: based on whether or not the relay node is at a first hop of the relay network, establish a connection with the core network for the relay node, wherein: when the relay node is not at the first hop of a relay network, the connection comprises a data radio bearer, DRB, without a user plane tunnel, or when the relay node is at the first hop of a relay network, the connection comprises a DRB and a user plane tunnel.

28. The relay node of Claim 27, wherein the relay node is configured to perform any of the methods of claims 2 to 14.

29. A core network node of a relay network configured to: establish a connection for a relay node, wherein: when the relay node is not at a first hop of a relay network, the connection comprises a data radio bearer, DRB, without a user plane tunnel, or when the relay node is at the first hop of a relay network, the connection comprises a DRB and a user plane tunnel.

30. The relay node of Claim 29, wherein the relay node is configured to perform any of the methods of claims 16 to 26.

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