WO2025118648A9

WO2025118648A9 - User plane function selection

Info

Publication number: WO2025118648A9
Application number: PCT/CN2024/108863
Authority: WO
Inventors: Haiyan Luo; Genadi Velev; Lizhuo ZHENG; Yibin ZHUO
Original assignee: Lenovo Beijing Ltd
Current assignee: Lenovo Beijing Ltd
Priority date: 2024-07-31
Filing date: 2024-07-31
Publication date: 2025-08-14
Anticipated expiration: 2027-01-31
Also published as: WO2025118648A1

Abstract

Various aspects of the present disclosure relate to methods, apparatuses, and systems that supports UPF selection. Some implementations of the method and apparatuses described herein may include a network node comprising a 5G Node-B (gNB) to be connected to a first network and a user equipment (UE) connected to a second network, wherein the UE comprises: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the UE to: send, to a session management function (SMF) of the second network, an establishment request for a Protocol Data Unit (PDU) session between the UE and a user plane function (UPF) of the second network along with first information associated with the first network, so that the gNB is capable of connecting to the first network.

Description

USER PLANE FUNCTION SELECTION

TECHNICAL FIELD

The present disclosure relates to wireless communications, and more specifically to User Plane Function (UPF) selection.

BACKGROUND

A wireless communications system may include one or multiple network communication devices, such as base stations, which may be otherwise known as an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. Each network communication devices, such as a base station may support wireless communications for one or multiple user communication devices, which may be otherwise known as user equipment (UE) , or other suitable terminology. The wireless communications system may support wireless communications with one or multiple user communication devices by utilizing resources of the wireless communication system (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) . Additionally, the wireless communications system may support wireless communications across various radio access technologies including third generation (3G) radio access technology, fourth generation (4G) radio access technology, fifth generation (5G) radio access technology, among other suitable radio access technologies beyond 5G (e.g., sixth generation (6G) ) .

This disclosure targets UPF selection.

SUMMARY

An article “a” before an element is unrestricted and understood to refer to “at least one” of those elements or “one or more” of those elements. The terms “a, ” “at least one, ” “one or more, ” and “at least one of one or more” may be interchangeable. As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” or “one or both of” ) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. Further, as used herein, including in the claims, a “set” may include one or more elements.

The present disclosure relates to methods, apparatuses, and systems that support UPF selection.

Some implementations of the method and apparatuses described herein may include a network node, comprising a 5G Node-B (gNB) to be connected to a first network and a user equipment (UE) connected to a second network, wherein the UE comprises: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the UE to: send, to a session management function (SMF) of the second network, an establishment request for a Protocol Data Unit (PDU) session between the UE and a user plane function (UPF) of the second network along with first information associated with the first network, so that the gNB is capable of connecting to the first network.

Some implementations of the method and apparatuses described herein may include a method performed by a user equipment (UE) in a network node, wherein the network node comprises a 5G Node-B (gNB) to be connected to a first network and the UE connected to a second network, the method comprising: sending, to a session management function (SMF) of the second network, an establishment request for a Protocol Data Unit (PDU) session between the UE and a user plane function (UPF) of the second network along with first information associated with the first network, so that the gNB is capable of connecting to the first network.

In some implementations of the method and apparatuses described herein, the first information associated with the first network comprises single network slice selection assistance information (S-NSSAI) or a combination of data network name (DNN) and S-NSSAI, of the second network.

In some implementations of the method and apparatuses described herein, the processor is further configured to cause the UE to receive, from the gNB, second information associated with the first network. The processor may be further configured to cause the UE to derive the first information associated with the first network from the second information associated with the first network.

In some implementations of the method and apparatuses described herein, the first information associated with the first network relates either to public land mobile network (PLMN) information of the first network, or to single network slice selection assistance information (S-NSSAI) , or a combination of data network name (DNN) and single network slice selection assistance information (S-NSSAI) , of the second network that can be mapped to the PLMN information of the first network. The PLMN information of the first network includes at least one of PLMN ID and operations and management (OAM) information. The OAM information of the first network includes at least one of internet protocol (IP) address, IP domain, and Fully Qualified Domain Name (FQDN) .

In some embodiment, the second information associated with the first network is either PLMN information of the first network, or S-NSSAI or a combination of DNN and S-NSSAI of the second network, that can be mapped to the PLMN information of the first network. The mapping of the S-NSSAI, or the combination of DNN and S-NSSAI, of the second network to the PLMN information of the first network is based on UE Route Selection Policy (URSP) rule.

In some embodiment, the at least one processor is configured to cause the UE to: check whether the first network is the same as the second network, and only when the first network is different from the second network, send the first information associated with the first network to the SMF of the second network.

Some implementations of the method and apparatuses described herein may include a session management function (SMF) of a second network, comprising: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the SMF to: receive, from a user equipment (UE) of a network node comprising the UE and a 5G Node-B (gNB) , an establishment request for a protocol data unit (PDU) session between the UE and a user plane function (UPF) of the second network, along with information associated with a first network to which the gNB of the network node is to be connected; and select, based on at least the information associated with the first network, the UPF of the second network that is capable of connecting to the first network.

Some implementations of the method and apparatuses described herein may include a method performed by a SMF of a second network, the method comprising: receiving, from a user equipment (UE) of a network node comprising the UE and a 5G Node-B (gNB) , an establishment request for a protocol data unit (PDU) session between the UE and a user plane function (UPF) of the second network, along with information associated with a first network to which the gNB of the network node is to be connected; and selecting, based on at least the information associated with the first network, the UPF of the second network that is capable of connecting to the first network.

In some implementations of the method and apparatuses described herein, the information associated with the first network relates to S-NSSAI, or a combination of DNN and S-NSSAI, of the second network.

In some implementations of the method and apparatuses described herein, the information associated with the first network relates to a public land mobile network (PLMN) information of the first network, or S-NSSAI, or a combination of DNN and S-NSSAI, of the second network that can be mapped to the PLMN information of the first network.

Some implementations of the method and apparatuses described herein may include an access and mobility function (AMF) of a second network, comprising: at least one memory; and at least one processor coupled with the at least one memory and configured to cause the AMF to: receive, from a user equipment (UE) of a network node comprising the UE and a 5G Node-B (gNB) , an establishment request for a protocol data unit (PDU) session between the UE and a user plane function (UPF) of the second network, along with first information associated with a first network to which the gNB of the network node is to be connected; and send, to a session management function (SMF) of the second network, the establishment request for the PDU session along with second information associated with the first network for the SMF to select the UPF that is capable of connecting to the first network, based on at least the second information associated with the first network.

Some implementations of the method and apparatuses described herein may include a method performed by an AMF of a second network, the method comprising: receiving, from a user equipment (UE) of a network node comprising the UE and a 5G Node-B (gNB) , an establishment request for a protocol data unit (PDU) session between the UE and a user plane function (UPF) of the second network, along with first information associated with a first network to which the gNB of the network node is to be connected; and sending, to a session management function (SMF) of the second network, the establishment request for the PDU session along with second information associated with the first network for the SMF to select the UPF that is capable of connecting to the first network, based on at least the second information associated with the first network.

In some implementations of the method and apparatuses described herein, the at least one processor is configured to cause the AMF to: derive the second information associated with the first network from the first information associated with the first network.

In some implementations of the method and apparatuses described herein, the first information associated with the first network relates to a public land mobile network (PLMN) information of the first network, or to S-NSSAI, or a combination of DNN and S-NSSAI, of the second network that can be mapped to the PLMN information of the first network.

In some implementations of the method and apparatuses described herein, the first information associated with the first network is S-NSSAI, or a combination of DNN and S-NSSAI, of the second network.

In some implementations of the method and apparatuses described herein, the processor is further configured to cause the AMF to: check whether the first network is the same as the second network; and only when the first network is different from the second network, send the second information associated with the first network to the SMF of the second network along with the establishment request for the PDU session.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 illustrates an example of a wireless communications system in accordance with aspects of the present disclosure.

Figure 2 illustrates an example of a user equipment (UE) 200 in accordance with aspects of the present disclosure.

Figure 3 illustrates an example of a processor 300 in accordance with aspects of the present disclosure.

Figure 4 illustrates an example of a network equipment (NE) 400 in accordance with aspects of the present disclosure.

Figure 5 illustrates an example architecture for the MWAB (mobile gNB with wireless access backhauling) operation.

Figure 6 illustrates protocol stacks of backhaul link to support N2 interface for MWAB node.

Figure 7 illustrates an implementation of the first embodiment.

Figure 8 illustrates an implementation of the second embodiment.

Figure 9 illustrates an implementation of obtaining URSP (UE Route Selection Policy) rule (s) .

Figure 10 illustrates an implementation of the third embodiment

Figure 11 illustrates an example architecture for roaming with Home Routed that supports MWAB operation.

Figure 12 illustrates a flowchart of method performed by a MWAB node in accordance with aspects of the present disclosure.

Figure 13 illustrates a flowchart of method performed by an SMF (Session Management Function) in accordance with aspects of the present disclosure.

Figure 14 illustrates a flowchart of method performed by an AMF (Access and Mobility Management Function) in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

Aspects of the present disclosure are described in the context of a wireless communications system.

Figure 1 illustrates an example of a wireless communications system 100 in accordance with aspects of the present disclosure. The wireless communications system 100 may include one or more NE 102, one or more UE 104, and a core network (CN) 106. The wireless communications system 100 may support various radio access technologies. In some implementations, the wireless communications system 100 may be a 4G network, such as an LTE (Long Term Evolution) network or an LTE-Advanced (LTE-A) network. In some other implementations, the wireless communications system 100 may be a New Radio (NR) network, such as a 5G network, a 5G-Advanced (5G-A) network, or a 5G ultrawideband (5G-UWB) network. In other implementations, the wireless communications system 100 may be a combination of a 4G network and a 5G network, or other suitable radio access technology including Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, etc. The wireless communications system 100 may support radio access technologies beyond 5G, for example, 6G. Additionally, the wireless communications system 100 may support technologies, such as time division multiple access (TDMA) , frequency division multiple access (FDMA) , or code division multiple access (CDMA) , etc.

The one or more NE 102 may be dispersed throughout a geographic region to form the wireless communications system 100. One or more of the NE 102 described herein may be or include or may be referred to as a network node, a base station, a network element, a network function, a network entity, a radio access network (RAN) , a NodeB, an eNodeB (eNB) , a next-generation NodeB (gNB) , or other suitable terminology. An NE 102 and a UE 104 may communicate via a communication link 110, which may be a wireless or wired connection. For example, an NE 102 and a UE 104 may perform wireless communication (e.g., receive signaling, transmit signaling) over a Uu interface.

An NE 102 may provide a geographic coverage area for which the NE 102 may support services for one or more UEs 104 within the geographic coverage area. For example, an NE 102 and a UE 104 may support wireless communication of signals related to services (e.g., voice, video, packet data, messaging, broadcast, etc. ) according to one or multiple radio access technologies. In some implementations, an NE 102 may be moveable, for example, a satellite associated with a non-terrestrial network (NTN) . In some implementations, different geographic coverage areas 112 associated with the same or different radio access technologies may overlap, but the different geographic coverage areas may be associated with different NE 102.

The one or more UE 104 may be dispersed throughout a geographic region of the wireless communications system 100. A UE 104 may include or may be referred to as a remote unit, a mobile device, a wireless device, a remote device, a subscriber device, a transmitter device, a receiver device, or some other suitable terminology. In some implementations, the UE 104 may be referred to as a unit, a station, a terminal, or a client, among other examples. Additionally, or alternatively, the UE 104 may be referred to as an Internet-of-Things (IoT) device, an Internet-of-Everything (IoE) device, or machine-type communication (C) device, among other examples.

A UE 104 may be able to support wireless communication directly with other UEs 104 over a communication link. For example, a UE 104 may support wireless communication directly with another UE 104 over a device-to-device (D2D) communication link. In some implementations, such as vehicle-to-vehicle (V2V) deployments, vehicle-to-everything (V2X) deployments, or cellular-V2X deployments, the communication link 114 may be referred to as a sidelink. For example, a UE 104 may support wireless communication directly with another UE 104 over a PC5 interface.

An NE 102 may support communications with the CN 106, or with another NE 102, or both. For example, an NE 102 may interface with other NE 102 or the CN 106 through one or more backhaul links 116 (e.g., S1, N2, or another network interface) . The network entities 102 may communicate with each other over the backhaul links 116 (e.g., via an X2, Xn, or another network interface) . In some implementations, the NE 102 may communicate with each other directly. In some other implementations, the NE 102 may communicate with each other or indirectly (e.g., via the CN 106) . In some implementations, one or more NE 102 may include subcomponents, such as an access network entity, which may be an example of an access node controller (ANC) . An ANC may communicate with the one or more UEs 104 through one or more other access network transmission entities, which may be referred to as a radio heads, smart radio heads, or transmission-reception points (TRPs) .

The CN 106 may support user authentication, access authorization, tracking, connectivity, and other access, routing, or mobility functions. The CN 106 may be an evolved packet core (EPC) , or a 5G core (5GC) , which may include a control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management functions (AMF) ) and a user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . In some implementations, the control plane entity may manage non-access stratum (NAS) functions, such as registration management, mobility management, connection management, access authentication/authorization, etc. for the one or more UEs 104 served by the one or more NE 102 associated with the CN 106.

The CN 106 may communicate with a packet data network 108 over one or more backhaul links (e.g., via an S1, N2, or another network interface) . The packet data network 108 may include an application server 118. In some implementations, one or more UEs 104 may communicate with the application server 118. A UE 104 may establish a session (e.g., a protocol data unit (PDU) session, or the like) with the CN 106 via an NE 102. The CN 106 may route traffic (e.g., control information, data, and the like) between the UE 104 and the application server 118 using the established session (e.g., the established PDU session) . The PDU session may be an example of a logical connection between the UE 104 and the CN 106 (e.g., one or more network functions of the CN 106) .

In the wireless communications system 100, the NEs 102 and the UEs 104 may use resources of the wireless communications system 100 (e.g., time resources (e.g., symbols, slots, subframes, frames, or the like) or frequency resources (e.g., subcarriers, carriers) ) to perform various operations (e.g., wireless communications) . In some implementations, the NEs 102 and the UEs 104 may support different resource structures. For example, the NEs 102 and the UEs 104 may support different frame structures. In some implementations, such as in 4G, the NEs 102 and the UEs 104 may support a single frame structure. In some other implementations, such as in 5G and among other suitable radio access technologies, the NEs 102 and the UEs 104 may support various frame structures (i.e., multiple frame structures) . The NEs 102 and the UEs 104 may support various frame structures based on one or more numerologies.

One or more numerologies may be supported in the wireless communications system 100, and a numerology may include a subcarrier spacing and a cyclic prefix. A first numerology (e.g., μ=0) may be associated with a first subcarrier spacing (e.g., 15 kHz) and a normal cyclic prefix. In some implementations, the first numerology (e.g., μ=0) associated with the first subcarrier spacing (e.g., 15 kHz) may utilize one slot per subframe. A second numerology (e.g., μ=1) may be associated with a second subcarrier spacing (e.g., 30 kHz) and a normal cyclic prefix. A third numerology (e.g., μ=2) may be associated with a third subcarrier spacing (e.g., 60 kHz) and a normal cyclic prefix or an extended cyclic prefix. A fourth numerology (e.g., μ=3) may be associated with a fourth subcarrier spacing (e.g., 120 kHz) and a normal cyclic prefix. A fifth numerology (e.g., μ=4) may be associated with a fifth subcarrier spacing (e.g., 240 kHz) and a normal cyclic prefix.

A time interval of a resource (e.g., a communication resource) may be organized according to frames (also referred to as radio frames) . Each frame may have a duration, for example, a 10 millisecond (ms) duration. In some implementations, each frame may include multiple subframes. For example, each frame may include 10 subframes, and each subframe may have a duration, for example, a 1 ms duration. In some implementations, each frame may have the same duration. In some implementations, each subframe of a frame may have the same duration.

Additionally or alternatively, a time interval of a resource (e.g., a communication resource) may be organized according to slots. For example, a subframe may include a number (e.g., quantity) of slots. The number of slots in each subframe may also depend on the one or more numerologies supported in the wireless communications system 100. For instance, the first, second, third, fourth, and fifth numerologies (i.e., μ=0, μ=1, μ=2, μ=3, μ=4) associated with respective subcarrier spacings of 15 kHz, 30 kHz, 60 kHz, 120 kHz, and 240 kHz may utilize a single slot per subframe, two slots per subframe, four slots per subframe, eight slots per subframe, and 16 slots per subframe, respectively. Each slot may include a number (e.g., quantity) of symbols (e.g., OFDM symbols) . In some implementations, the number (e.g., quantity) of slots for a subframe may depend on a numerology. For a normal cyclic prefix, a slot may include 14 symbols. For an extended cyclic prefix (e.g., applicable for 60 kHz subcarrier spacing) , a slot may include 12 symbols. The relationship between the number of symbols per slot, the number of slots per subframe, and the number of slots per frame for a normal cyclic prefix and an extended cyclic prefix may depend on a numerology. It should be understood that reference to a first numerology (e.g., μ=0) associated with a first subcarrier spacing (e.g., 15 kHz) may be used interchangeably between subframes and slots.

In the wireless communications system 100, an electromagnetic (EM) spectrum may be split, based on frequency or wavelength, into various classes, frequency bands, frequency channels, etc. By way of example, the wireless communications system 100 may support one or multiple operating frequency bands, such as frequency range designations FR1 (410 MHz - 7.125 GHz) , FR2 (24.25 GHz - 52.6 GHz) , FR3 (7.125 GHz - 24.25 GHz) , FR4 (52.6 GHz - 114.25 GHz) , FR4a or FR4-1 (52.6 GHz - 71 GHz) , and FR5 (114.25 GHz - 300 GHz) . In some implementations, the NEs 102 and the UEs 104 may perform wireless communications over one or more of the operating frequency bands. In some implementations, FR1 may be used by the NEs 102 and the UEs 104, among other equipment or devices for cellular communications traffic (e.g., control information, data) . In some implementations, FR2 may be used by the NEs 102 and the UEs 104, among other equipment or devices for short-range, high data rate capabilities.

FR1 may be associated with one or multiple numerologies (e.g., at least three numerologies) . For example, FR1 may be associated with a first numerology (e.g., μ=0) , which includes 15 kHz subcarrier spacing; a second numerology (e.g., μ=1) , which includes 30 kHz subcarrier spacing; and a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing. FR2 may be associated with one or multiple numerologies (e.g., at least 2 numerologies) . For example, FR2 may be associated with a third numerology (e.g., μ=2) , which includes 60 kHz subcarrier spacing; and a fourth numerology (e.g., μ=3) , which includes 120 kHz subcarrier spacing.

Figure 2 illustrates an example of a UE 200 in accordance with aspects of the present disclosure. The UE 200 may include a processor 202, a memory 204, a controller 206, and a transceiver 208. The processor 202, the memory 204, the controller 206, or the transceiver 208, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. These components may be coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces.

The processor 202, the memory 204, the controller 206, or the transceiver 208, or various combinations or components thereof may be implemented in hardware (e.g., circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , or other programmable logic device, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure.

The processor 202 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, or any combination thereof) . In some implementations, the processor 202 may be configured to operate the memory 204. In some other implementations, the memory 204 may be integrated into the processor 202. The processor 202 may be configured to execute computer-readable instructions stored in the memory 204 to cause the UE 200 to perform various functions of the present disclosure.

The memory 204 may include volatile or non-volatile memory. The memory 204 may store computer-readable, computer-executable code including instructions when executed by the processor 202 cause the UE 200 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such the memory 204 or another type of memory. Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer.

In some implementations, the processor 202 and the memory 204 coupled with the processor 202 may be configured to cause the UE 200 to perform one or more of the functions described herein (e.g., executing, by the processor 202, instructions stored in the memory 204) . For example, the processor 202 may support wireless communication at the UE 200 in accordance with examples as disclosed herein. The UE 200 may be configured to support a means for determining that a Physical Uplink Shared Channel (PUSCH) transmission is associated with a plurality of Phase-Tracking Reference Signal (PTRS) ports; and transmitting the PUSCH transmission together with the plurality of PTRS ports.

The controller 206 may manage input and output signals for the UE 200. The controller 206 may also manage peripherals not integrated into the UE 200. In some implementations, the controller 206 may utilize an operating system such as or other operating systems. In some implementations, the controller 206 may be implemented as part of the processor 202.

In some implementations, the UE 200 may include at least one transceiver 208. In some other implementations, the UE 200 may have more than one transceiver 208. The transceiver 208 may represent a wireless transceiver. The transceiver 208 may include one or more receiver chains 210, one or more transmitter chains 212, or a combination thereof.

A receiver chain 210 may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receiver chain 210 may include one or more antennas for receive the signal over the air or wireless medium. The receiver chain 210 may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receiver chain 210 may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receiver chain 210 may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

A transmitter chain 212 may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmitter chain 212 may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmitter chain 212 may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmitter chain 212 may also include one or more antennas for transmitting the amplified signal into the air or wireless medium.

Figure 3 illustrates an example of a processor 300 in accordance with aspects of the present disclosure. The processor 300 may be an example of a processor configured to perform various operations in accordance with examples as described herein. The processor 300 may include a controller 302 configured to perform various operations in accordance with examples as described herein. The processor 300 may optionally include at least one memory 304, which may be, for example, an L1/L2/L3 cache. Additionally, or alternatively, the processor 300 may optionally include one or more arithmetic-logic units (ALUs) 306. One or more of these components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces (e.g., buses) .

The processor 300 may be a processor chipset and include a protocol stack (e.g., a software stack) executed by the processor chipset to perform various operations (e.g., receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) in accordance with examples as described herein. The processor chipset may include one or more cores, one or more caches (e.g., memory local to or included in the processor chipset (e.g., the processor 300) or other memory (e.g., random access memory (RAM) , read-only memory (ROM) , dynamic RAM (DRAM) , synchronous dynamic RAM (SDRAM) , static RAM (SRAM) , ferroelectric RAM (FeRAM) , magnetic RAM (MRAM) , resistive RAM (RRAM) , flash memory, phase change memory (PCM) , and others) .

The controller 302 may be configured to manage and coordinate various operations (e.g., signaling, receiving, obtaining, retrieving, transmitting, outputting, forwarding, storing, determining, identifying, accessing, writing, reading) of the processor 300 to cause the processor 300 to support various operations in accordance with examples as described herein. For example, the controller 302 may operate as a control unit of the processor 300, generating control signals that manage the operation of various components of the processor 300. These control signals include enabling or disabling functional units, selecting data paths, initiating memory access, and coordinating timing of operations.

The controller 302 may be configured to fetch (e.g., obtain, retrieve, receive) instructions from the memory 304 and determine subsequent instruction (s) to be executed to cause the processor 300 to support various operations in accordance with examples as described herein. The controller 302 may be configured to track memory address of instructions associated with the memory 304. The controller 302 may be configured to decode instructions to determine the operation to be performed and the operands involved. For example, the controller 302 may be configured to interpret the instruction and determine control signals to be output to other components of the processor 300 to cause the processor 300 to support various operations in accordance with examples as described herein. Additionally, or alternatively, the controller 302 may be configured to manage flow of data within the processor 300. The controller 302 may be configured to control transfer of data between registers, arithmetic logic units (ALUs) , and other functional units of the processor 300.

The memory 304 may include one or more caches (e.g., memory local to or included in the processor 300 or other memory, such RAM, ROM, DRAM, SDRAM, SRAM, MRAM, flash memory, etc. In some implementations, the memory 304 may reside within or on a processor chipset (e.g., local to the processor 300) . In some other implementations, the memory 304 may reside external to the processor chipset (e.g., remote to the processor 300) .

The memory 304 may store computer-readable, computer-executable code including instructions that, when executed by the processor 300, cause the processor 300 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. The controller 302 and/or the processor 300 may be configured to execute computer-readable instructions stored in the memory 304 to cause the processor 300 to perform various functions. For example, the processor 300 and/or the controller 302 may be coupled with or to the memory 304, the processor 300, the controller 302, and the memory 304 may be configured to perform various functions described herein. In some examples, the processor 300 may include multiple processors and the memory 304 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions herein.

The one or more ALUs 306 may be configured to support various operations in accordance with examples as described herein. In some implementations, the one or more ALUs 306 may reside within or on a processor chipset (e.g., the processor 300) . In some other implementations, the one or more ALUs 306 may reside external to the processor chipset (e.g., the processor 300) . One or more ALUs 306 may perform one or more computations such as addition, subtraction, multiplication, and division on data. For example, one or more ALUs 306 may receive input operands and an operation code, which determines an operation to be executed. One or more ALUs 306 be configured with a variety of logical and arithmetic circuits, including adders, subtractors, shifters, and logic gates, to process and manipulate the data according to the operation. Additionally, or alternatively, the one or more ALUs 306 may support logical operations such as AND, OR, exclusive-OR (XOR) , not-OR (NOR) , and not-AND (NAND) , enabling the one or more ALUs 306 to handle conditional operations, comparisons, and bitwise operations.

The processor 300 may support wireless communication in accordance with examples as disclosed herein. The processor 300 may be configured to or operable to support a means for determining that a Physical Uplink Shared Channel (PUSCH) transmission is associated with a plurality of Phase-Tracking Reference Signal (PTRS) ports; and transmitting the PUSCH transmission together with the plurality of PTRS ports.

Figure 4 illustrates an example of a NE 400 in accordance with aspects of the present disclosure. The NE 400 may include a processor 402, a memory 404, a controller 406, and a transceiver 408. The processor 402, the memory 404, the controller 406, or the transceiver 408, or various combinations thereof or various components thereof may be examples of means for performing various aspects of the present disclosure as described herein. These components may be coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more interfaces.

The processor 402, the memory 404, the controller 406, or the transceiver 408, or various combinations or components thereof may be implemented in hardware (e.g., circuitry) . The hardware may include a processor, a digital signal processor (DSP) , an application-specific integrated circuit (ASIC) , or other programmable logic device, or any combination thereof configured as or otherwise supporting a means for performing the functions described in the present disclosure.

The processor 402 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, or any combination thereof) . In some implementations, the processor 402 may be configured to operate the memory 404. In some other implementations, the memory 404 may be integrated into the processor 402. The processor 402 may be configured to execute computer-readable instructions stored in the memory 404 to cause the NE 400 to perform various functions of the present disclosure.

The memory 404 may include volatile or non-volatile memory. The memory 404 may store computer-readable, computer-executable code including instructions when executed by the processor 402 cause the NE 400 to perform various functions described herein. The code may be stored in a non-transitory computer-readable medium such the memory 404 or another type of memory. Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer.

In some implementations, the processor 402 and the memory 404 coupled with the processor 402 may be configured to cause the NE 400 to perform one or more of the functions described herein (e.g., executing, by the processor 402, instructions stored in the memory 404) . For example, the processor 402 may support wireless communication at the NE 400 in accordance with examples as disclosed herein. The NE 400 may be configured to support a means for determining that a Physical Uplink Shared Channel (PUSCH) transmission is associated with a plurality of Phase-Tracking Reference Signal (PTRS) ports; and receiving the PUSCH transmission together with the plurality of PTRS ports.

The controller 406 may manage input and output signals for the NE 400. The controller 406 may also manage peripherals not integrated into the NE 400. In some implementations, the controller 406 may utilize an operating system such as or other operating systems. In some implementations, the controller 406 may be implemented as part of the processor 402.

In some implementations, the NE 400 may include at least one transceiver 408. In some other implementations, the NE 400 may have more than one transceiver 408. The transceiver 408 may represent a wireless transceiver. The transceiver 408 may include one or more receiver chains 410, one or more transmitter chains 412, or a combination thereof.

A receiver chain 410 may be configured to receive signals (e.g., control information, data, packets) over a wireless medium. For example, the receiver chain 410 may include one or more antennas for receive the signal over the air or wireless medium. The receiver chain 410 may include at least one amplifier (e.g., a low-noise amplifier (LNA) ) configured to amplify the received signal. The receiver chain 410 may include at least one demodulator configured to demodulate the receive signal and obtain the transmitted data by reversing the modulation technique applied during transmission of the signal. The receiver chain 410 may include at least one decoder for decoding the processing the demodulated signal to receive the transmitted data.

A transmitter chain 412 may be configured to generate and transmit signals (e.g., control information, data, packets) . The transmitter chain 412 may include at least one modulator for modulating data onto a carrier signal, preparing the signal for transmission over a wireless medium. The at least one modulator may be configured to support one or more techniques such as amplitude modulation (AM) , frequency modulation (FM) , or digital modulation schemes like phase-shift keying (PSK) or quadrature amplitude modulation (QAM) . The transmitter chain 412 may also include at least one power amplifier configured to amplify the modulated signal to an appropriate power level suitable for transmission over the wireless medium. The transmitter chain 412 may also include one or more antennas for transmitting the amplified signal into the air or wireless medium.

This disclosure relates to MWAB (mobile gNB with wireless access backhauling) . A mobile wireless backhaul node is defined as MWAB node consisting of a gNB component (MWAB-gNB) and a UE component (MWAB-UE) that are co-located. The MWAB node can be used as a Vehicle-Mounted Relay (VMR) .

Figure 5 illustrates an example architecture for the MWAB operation. MWAB-UE of the MWAB node connects to NG-RAN (Next Generation Radio Access Network) of PLMN#1 (public land mobile network #1) , and establishes PDU session (s) , which can be referred to as Backhauling (BH) PDU session (s) , with PLMN#1 (e.g., with MWAB-UPF) .

The BH PDU session (s) are used to transfer message and/or data between MWAB-gNB of the MWAB node and PLMN#2 (public land mobile network #2) , e.g., the message between MWAB-gNB and OAM (Operation Administration and Maintenance) node (which may be referred to as OAM server) (not shown in Figure 5) of PLMN#2; the N2 message between MWAB-gNB and UE-AMF; and the N3 data between MWAB-gNB and UE-UPF. In this way, UE connected to the MWAB-gNB is able to be served by PLMN#2 via the BH PDU session (s) provided by MWAB-UE from PLMN#1.

It can be seen that two PLMNs (i.e., PLMN#1 and PLMN#2) are present, where PLMN#1 serves MWAB-UE; and PLMN#2 serves UEs connected to MWAB-gNB. Since there is no direct connection between MWAB-gNB and PLMN#2, the connection between MWAB-gNB and PLMN#2 is achieved by BH PDU session (s) between MWAB-UE and PLMN#1 (e.g., between MWAB-UE and MWAB-UPF) . That is, MWAB-gNB to be connected to PLMN#2 is able to connect to PLMN#2 via BH PDU session (s) between MWAB-UE and PLMN#1.

Figure 6 illustrates protocol stacks of backhaul link to support the N2 interface for the MWAB node. MWAB-UE connects to BH-gNB (i.e., NG-RAN in Figure 5) . A PDU session between MWAB-UE and MWAB-UPF is established as a backhaul link to support the N2 interface between MWAB-gNB and UE-AMF, which includes NGAP (Next Generation Application Protocol) layer and (Stream Control Transmission Protocol) SCTP/IP layer between them. Thus, there is a connection between MWAB-UPF and UE-AMF. It means that when a MWAB-UPF is selected for the BH PDU session (which is used for the connection between MWAB-gNB and PLMN#2) between MWAB-UE and the MWAB-UPF, only the MWAB-UPF that can connect to UE-AMF of PLMN#2 can be selected. Similarly, the BH PDU session (s) between MWAB-UE and MWAB-UPF also support the connection of MWAB-gNB to UE-UPF and to the OAM server. As a whole, when an MWAB UPF is selected upon a BH PDU session (used for the connection between MWAB-gNB and PLMN#2) being established between MWAB-UE and the MWAB-UPF, only the MWAB UPF that can connect to PLMN#2 (e.g., to UE-AMF, UE-UPF and the OAM server of PLMN#2) can be selected. As a whole, MWAB-gNB can connect to PLMN#2 through the MWAB-UPF that can connect to PLMN#2.

The problem is: since MWAB-UE establishes BH PDU session (s) with MWAB-UPF before MWAB-gNB establishes connection with the OAM server (as well as the N2 interface towards UE-AMF and the N3 interface towards UE-UPF) of PLMN#2, how could MWAB-SMF, when it selects MWAB-UPF, knows that the BH PDU session will be used to connect with PLMN#2 (e.g., OAM server, UE-AMF, UE-UPF of PLMN#2) . That is, how could MWAB-SMF be able to select MWAB-UPF to provide for the connection between MWAB-gNB and the OAM server of PLMN#2, for N2 interface between MWAB-gNB and UE-AMF of PLMN#2, and for N3 interface between MWAB-gNB and UE-UPF of PLMN#2? This application aims to solve the above problem. Depending on deployment requirement, a security gateway may be required between the MWAB-UPF and the OAM server or core network of PLMN#2. In that case, the MWAB-gNB needs to connect to the security gateway based on pre-configured security credentials. In that case, the traffic between MWAB-gNB and the PLMN#2 goes inside the security tunnel established via the security gateway.

According to a first embodiment, MWAB-UE provides PLMN info (e.g., of PLMN#2) to MWAB-SMF, so that MWAB-SMF is able to select, based on the PLMN info, appropriate MWAB-UPF for the BH PDU session between MWAB-UE and MWAB-UPF. That is, the selected MWAB-UPF is able to connect to PLMN#2 (e.g., OAM server, UE-AMF, UE-SMF of PLMN#2) .

PLMN info may include at least one of PLMN ID (e.g., ID of PLMN#2) and OAM info (e.g., of PLMN#2) . The OAM info may be at least one of OAM IP address (e.g., OAM server address) , IP domain (s) , FQDN (Fully Qualified Domain Name) . It is assumed that the PLMN ID can be inferred based on the OAM info, for example, since MWAB-SMF is preconfigured with mapping relation between OAM info and PLMN ID. In case that MWAB-gNB supports MOCN (Multi-Operator Core Network) RAN sharing, PLMN info may be a list of PLMN info, e.g., a list of PLMN IDs.

It is assumed that MWAB-gNB is pre-configured with PLMN info (e.g., PLMN ID) of PLMN#2, i.e., the PLMN that serves the UE connected to MWAB-gNB.

Figure 7 illustrates an implementation of the first embodiment.

In step 710, MWAB-gNB sends target PLMN info to MWAB-UE. The target PLMN info is the target PLMN info of MWAB-gNB, that is, the PLMN info of the PLMN (e.g., PLMN#2) that serves UEs connected to MWAB-gNB.

Steps 720, 730, 740, 750, 760 and 770 are basically the steps of PDU session establishment procedure. The new parameter “target PLMN info of MWAB-gNB” proposed in this application is added in the PDU session establishment procedure.

In step 720, MWAB-UE sends PDU session establishment request to MWAB-AMF. Along with the PDU session establishment request, the target PLMN info (e.g., PLMN info of PLMN#2) is also sent to MWAB-AMF. One implementation of sending the target PLMN info is by containing the target PLMN info in the PDU session establishment request. Alternatively, the target PLMN info can be sent to MWAB-AMF in parallel with the PDU session establishment request. For example, MWAB-UE sends, to MWAB-AMF, a UL NAS message containing PDU Session Establishment request (which can be regarded as NAS-SM (Non Access Stratum Session Management) container) and the target PLMN info.

Besides, MWAB-UE also provides UE requested DNN (Data Network Name) , S-NSSAI (Single Network Slice Selection Assistance Information) and etc. together with PDU Session Establishment Request, as required by the existing specification for PDU session establishment procedure.

Incidentally, the first embodiment assumes that MWAB-UE and MWAB-gNB connect to different PLMNs. That is, the PLMN (e.g., PLMN#1) to which MWAB-UE connects and the PLMN (e.g., PLMN#2) to which MWAB-gNB connects are different PLMNs. Nevertheless, it is possible that PLMN#1 and PLMN#2 are the same PLMN. Accordingly, before step 720, MWAB-UE may check whether the target PLMN indicated by the target PLMN info is the PLMN that MWAB-UE is connected to. If the target PLMN is different from the PLMN that MWAB-UE is connected to, then proceed to step 720 and the following steps. If the target PLMN is the same as the PLMN that MWAB-UE is connected to, MWAB-UE may instead perform traditional PDU Session Establishment procedure, which means that MWAB-UE is not necessary to send the target PLMN info in step 720.

In step 730, MWAB-AMF selects SMF based on the existing specification defined in TS 23.501 6.3.2.

In step 740, MWAB-AMF sends, to the MWAB-SMF selected in step 730, PDU Session Establishment request and the target PLMN info. The target PLMN info can be sent to MWAB-AMF separately from the PDU Session Establishment request. For example, MWAB-AMF triggers Nsmf_PDUSession_CreateSMContext Request towards MWAB-SMF, which contains PDU Session Establishment request and the target PLMN info. Alternatively, the target PLMN info can be sent to MWAB-SMF by being included in the PDU Session Establishment request. In this condition, MWAB-AMF just contains PDU Session Establishment request including the target PLMN info in Nsmf_PDUSession_CreateSMContext Request.

Incidentally, before step 740, in the condition that the target PLMN info is received in step 720, MWAB-AMF may check whether the target PLMN indicated by the target PLMN info is the PLMN that MWAB-UE is connected to. If the target PLMN is different from the PLMN that MWAB-UE is connected to, then proceed to step 740 and the following steps. If the target PLMN is the same as the PLMN that MWAB-UE is connected to, MWAB-AMF may instead proceed to traditional PDU Session Establishment procedure, which means that MWAB-AMF is not necessary to send the target PLMN info in step 740.

In step 750, MWAB-SMF performs UPF selection at least based on the target PLMN info. It means that MWAB-SMF performs UPF selection based on the target PLMN info in addition to existing selection criteria. MWAB-SMF obtains the target PLMN info directly from Nsmf_PDUSession_CreateSMContext Request transmitted by MWAB-AMF or from PDU Session Establishment request contained in Nsmf_PDUSession_CreateSMContext Request. If the target PLMN info is provided in the form of OAM info, it is assumed that MWAB-SMF is pre-configured with the mapping of OAM info and the target PLMN info. Alternatively, MWAB-SMF obtains the mapping of OAM info and the target PLMN info from the subscription data. That is, MWAB-SMF selects, based on the target PLMN info, a MWAB-UPF that is able to provide the connection to the target PLMN, such as PLMN#2 (e.g., the OAM server, UE-AMF and UE-UPF of PLMN#2) .

In step 760, MWAB-SMF triggers N4 Session establishment procedure towards MWAB-UPF selected in step 750.

In step 770, MWAB-SMF sends PDU Session Establishment Accept to MWAB-UE.

As a whole, BH PDU session is established between MWAB-UE and the MWAB-UPF that is able to provide the connection to the target PLMN (e.g., PLMN#2) . When MWAB-gNB establishes the connection to the OAM server of the target PLMN (e.g., PLMN#2) by using the BH PDU session, the MWAB-UPF is able to provide the connection to the OAM server of the target PLMN (e.g., PLMN#2) . When MWAB-gNB establishes N2 interface to the target AMF (e.g., UE-AMF of PLMN#2) , MWAB-UPF is able to provide the connection to the target AMF. When MWAB-gNB establishes N3 interface to the target UPF (e.g., UE-UPF of the PLMN#2) , MWAB-UPF is able to provide the connection to the target UPF. Incidentally, OAM connection, N2 interface and N3 interface may share the same BH PDU session or use separate BH PDU sessions, respectively.

According to a second embodiment, MWAB-UE provides DNN (Data Network Name) and S-NSSAI (Single Network Slice Selection Assistance Information) of PLMN#1 that can be mapped to PLMN info of PLMN#2 to MWAB-SMF. MWAB-SMF is able to map DNN and S-NSSAI of PLMN#1 to target PLMN info of PLMN#2, and select, based on the target PLMN info, appropriate MWAB-UPF for the BH PDU session between MWAB-UE and MWAB-UPF. That is, the selected MWAB-UPF can connect to PLMN#2 (e.g., the OAM server, UE-AMF, UE-SMF of PLMN#2) .

Figure 8 illustrates an implementation of the second embodiment.

It is assumed that MWAB-SMF is pre-configured with the mapping of the target PLMN info of PLMN#2 and (DNN, S-NSSAI) of PLMN#1. (DNN, S-NSSAI) stands for ‘S-NSSAI’ or ‘DNN and S-NSSAI’ . If the target PLMN info is mapped only to S-NSSAI, DNN can be derived from S-NSSAI.

In step 810, MWAB-gNB provides the target PLMN info to MWAB-UE.

In step 820, MWAB-UE maps the target PLMN info (e.g., of PLMN#2) into (DNN, S-NSSAI) of PLMN#1. In this case, (DNN, S-NSSAI) are related with PLMN#1 (i.e., the PLMN that serves MWBA-UE) , while the target PLMN info is related with PLMN#2 (i.e., the PLMN that serves UEs connected to MWAB-gNB) .

At least three implementation options for the MWAB-UE to obtain the mapping of PLMN info and (DNN, S-NSSAI) are proposed.

In option#1, it is assumed that MWAB-UE is pre-configured with the mapping of the PLMN info of PLMN#2 and (DNN, S-NSSAI) of PLMN#1.

In option#2, it is assumed that MWAB-UE performs the mapping based on URSP rule. That is, URSP rule includes the mapping of the PLMN info of PLMN#2 and (DNN, S-NSSAI) of PLMN#1. Generally, URSP rule includes traffic descriptor and the corresponding Route Selection Descriptor (s) . In this case, it is assumed that traffic descriptor includes PLMN info (e.g., of PLMN#2) , and the corresponding Route Selection Descriptor (s) include (DNN, S-NSSAI) of PLMN#1.

In option#3, it is assumed that the mapping relationship may be contained as the subscription data of MWAB-UE in UDM (Unified Data Management) (e.g., in UDR (Unified Data Repository) ) . It means that the subscription data is stored in UDM while UDM may choose to store the subscription data in UDR. It is assumed that MWAB-AMF obtains the mapping relationship from UDM (e.g., from UDR) upon MWAB-UE registration or configuration update. Then, MWAB-AMF provides the mapping relationship to MWAB-UE via DL (downlink) NAS message.

Alternatively to steps 810 and 820, if it is assumed that MWAB-gNB is configured (e.g., by OAM server) with (DNN, S-NSSAI) (e.g., of PLMN#1) that can be mapped to the PLMN info (e.g., of PLMN#2) , then MWAB-gNB may directly send (DNN, S-NSSAI) to MWAB-UE.

In step 830, MWAB-UE sends the PDU Session Establishment request, DNN and S-NSSAI (s) to MWAB-AMF. DNN may be UE requested DNN (i.e., the DNN mapped in step 820) .

In step 840, MWAB-AMF selects SMF (i.e., MWAB-SMF) based on the existing specification defined in TS 23.501 6.3.2.

In step 850, MWAB-AMF sends, to MWAB-SMF selected in step 840, PDU Session Establishment request and selected DNN, UE requested DNN, S-NSSAI (s) . If DNN replacement is allowed, then MWAB-AMF may select a selected DNN subject for replacement, i.e., select the selected DNN instead of the UE requested DNN. If DNN replacement is not allowed, UE requested DNN is the same as the selected DNN. Although the selected DNN is intended to replace the UE requested DNN for the selection of UPF, both the selected DNN and the UE requested DNN may be sent in step 850, because the UE requested DNN may have other usage than UPF selection. Selected DNN or UE requested DNN, which is used for UPF selection, is referred to as DNN hereinafter.

In step 860, MWAB-SMF derives target PLMN info from (DNN, S-NSSAI) . It is assumed that MWAB-SMF is pre-configured with the mapping of PLMN info and (DNN, S-NSSAI) . Besides, it is assumed that either (UE Requested DNN, S-NSSAI) or (selected DNN, S-NSSAI) maps to the same PLMN info. Alternatively, it is assumed that the mapping relationship may be contained as the subscription data of MWAB-UE in UDM (e.g., in UDR) . It is assumed that MWAB-SMF obtains the mapping relationship from UDM (e.g., UDR) upon MWAB-UE registration or configuration update.

In step 870, MWAB-SMF performs UPF selection at least based on target PLMN info. It means that MWAB-SMF performs UPF selection based on the target PLMN info in addition to existing selection criteria. That is, MWAB-SMF selects MWAB-UPF that is able to provide the connection to the OAM server, UE-AMF and UE-UPF of the target PLMN (e.g., PLMN#2) .

In step 880, MWAB-SMF triggers N4 Session establishment procedure towards the MWAB-UPF selected in step 870.

In step 890, MWAB-SMF sends PDU Session Establishment Accept to MWAB-UE.

As a whole, according to the second embodiment, BH PDU session is established between MWAB-UE and MWAB-UPF that is able to provide the connection to the target PLMN.

Figure 9 illustrates option#2 in step 820, that is, an implementation of obtaining URSP rule (s) including mapping of PLMN info and (DNN, S-NSSAI) .

In step 910, MWAB-UE sends registration request to MWAB-AMF via BH gNB.

In step 920, MWAB-AMF requests MWAB-UDM for MWAB-UE’s subscription data. For example, MWAB-AMF sends, to MWAB-UDM, Nudm_UECM_Registration or Nudm_SDM_Get or Nudm_SDM_Subscribe. MWAB- UDM responses with MWAB-UE’s subscription data which may contain MWAB-operation-allowed indication. For example, MWAB-operation-allowed indication may be contained in Access and Mobility Subscription data, or SMF Selection Subscription data, or UE context in SMF data.

In step 930, MWAB-AMF triggers UE Policy Association Establishment with MWAB-PCF (Policy Control Function) . For example, MWAB-AMF sends, to MWAB-PCF, a Npcf_UEPolicyControl Create Request, which includes SUPI (Subscription Permanent Identifier) , PLMN ID (e.g., PLMN#1) , and MWAB-indication (which is optional) . MWAB-PCF sends, to MWAB-AMF, a Npcf_UEPolicyControl Create Response.

In step 940, MWAB-PCF sends, to MWAB-UDR, Nudr_UDM_Query which includes SUPI, PLMN ID and the MWAB-indication (which is optional) .

In step 950, MWAB-UDR responds to MWAB-PCF with the mapping of PLMN info (e.g., PLMN info and (DNN, S-NSSAI) ) . In one case, MWAB-UDR provides the mapping upon receiving the MWAB-indication. Alternatively, MWAB-UDR provides the mapping as long as the mapping is contained in the subscription data of the MWAB-UE.

In step 960, MWAB-PCF sends, to MWAB-UE, URSP rule including the mapping of PLMN info (e.g., of PLMN#2) and (DNN, S-NSSAI) (e.g., of PLMN#1) .

According to a third embodiment, MWAB-UE provides (DNN, S-NSSAI) (e.g., of PLMN#1) to MWAB-AMF. MWAB-AMF is able to map (DNN, S-NSSAI) (e.g., of PLMN#1) to target PLMN info (e.g., of PLMN#2) , and send the target PLMN info to MWAB-SMF. MWAB-SMF selects, based on the target PLMN info provided by MWAB-AMF, appropriate MWAB-UPF for the BH PDU session between MWAB-UE and MWAB-UPF. That is, the selected MWAB-UPF can connect to PLMN#2 (e.g., the OAM server, UE-AMF, UE-SMF of PLMN#2) .

Figure 10 illustrates an implementation of the third embodiment.

It is assumed that MWAB-AMF is pre-configured with the mapping of the target PLMN info (e.g., of PLMN#2) and (DNN, S-NSSAI) (e.g., of PLMN#1) .

Steps 1010-1040 are the same as steps 810-840, respectively. Thus, the detailed descriptions of steps 1010-1040 are omitted.

In step 1050, MWAB-AMF maps (DNN, S-NSSAI) (e.g., of PLMN#1) to target PLMN info (e.g., of PLMN#2) , where the DNN can be UE requested DNN or selected DNN. It is assumed that MWAB-AMF is pre-configured with the mapping of PLMN info (e.g., of PLMN#2) and (DNN, S-NSSAI) (e.g., of PLMN#1) . Besides, it is assumed that either (UE Requested DNN, S-NSSAI) or (selected DNN, S-NSSAI) maps to the same PLMN info. Alternatively, it is assumed that the mapping relationship may be contained as the subscription data of MWAB-UE in UDM (e.g., in UDR) , and MWAB-AMF obtains the mapping relationship from UDM (e.g., from UDR) upon MWAB-UE registration or configuration update.

In step 1060, MWAB-AMF sends, to MWAB-SMF, PDU Session Establishment request and target PLMN info.

In step 1070, MWAB-SMF performs UPF selection at least based on the target PLMN info. It means that MWAB-SMF performs UPF selection based on the target PLMN info in addition to existing selection criteria. That is, MWAB-SMF selects MWAB-UPF that is able to provide the connection to the OAM server, UE-AMF and UE-UPF of the target PLMN (e.g., PLMN#2) .

Steps 1080 and 1090 are the same as steps 880 and 980, respectively.

As a whole, according to the third embodiment, BH PDU session is established between MWAB-UE and MWAB-UPF that is able to provide the connection to the target PLMN.

According to all of the first, the second and the third embodiments, an PLMN indication (e.g., PLMN info (e.g., of PLMN#2) , or (DNN, S-NSSAI) (e.g., of PLMN#1) that can be mapped to PLMN info (e.g., of PLMN#2) ) that indicates the PLMN (e.g., PLMN#2) that serves the UEs connected to MWAB-gNB is provided to MWAB-SMF when an PDU session is established between MWAB-UE and MWAB-UPF, so that MWAB-SMF is able to select MWAB-UPF that is able to provide the connection to the target PLMN (i.e., the PLMN that serves the UEs connected to MWAB-gNB) , that is, MWAB-gNB is able to connect to the target PLMN (e.g., PLMN#2) .

According to a fourth embodiment, it is assumed that MWAB-UE may be configured with a dedicated (DNN, S-NSSAI) (e.g., of PLMN#1) for the BH PDU session (e.g., for PLMN#2) , e.g., by Local Configuration or URSP rules. It means that MWAB-gNB is not necessary to send any information related to PLMN#2 to MWAB-UE. Instead, accordingly to the fourth embodiment, only if MWAB-UE sends the dedicated (DNN, S-NSSAI) along with a PDU session establishment request, MWAB-SMF knows that the PDU session established in response to the PDU session establishment request is a BH PDU session (e.g., for PLMN#2) . That is, MWAB-SMF performs UPF selection at least based on the dedicated (DNN, S-NSSAI) (e.g., based on the dedicated (DNN, S-NSSAI) and existing selection criteria) , so that the selected MWAB-UPF is able to provide the connection to the target PLMN, such as PLMN#2 (e.g., the OAM server, UE-AMF and UE-UPF of PLMN#2) . Moreover, the selected MWAB-UPF may be a UPF that can connect to other PLMNs (e.g., in addition to PLMN#2) .

Figure 11 illustrates an example architecture for roaming with Home Routed that supports MWAB operation. In this case, PDU session of the MWAB-UE is routed by PLMN#1 (visiting PLMN) to the HPLMN (Home PLMN, e.g., PLMN#3) of the MWAB. MWAB-UE of the MWAB node connects to NG-RAN of the visiting PLMN#1, and establishes PDU session (s) , which can be referred to as Backhauling (BH) PDU session (s) , with MWAB HPLMN (e.g., with MWAB H-UPF) . NG-RAN, MWAB-UPF, V-SMF, MWAB AMF and MWAB PCF belong to the visiting PLMN#1. In this case, PLMN#1 may access the HPLMN UDM in MWAB HPLMN for the subscription information. V-SMF in PLMN#1 connects to H-SMF in MWAB HPLMN. It is the MWAB H-UPF in MWAB HPLMN connects to PLMN#2 (e.g., to UE-AMF, UE-UPF and the OAM server of PLMN#2) . In this case, V-SMF obtains target PLMN info (e.g., of PLMN#2) as shown in Figure 7 or Figure 10, or derives the target PLMN info (e.g., of PLMN#2) from (DNN, S-NSSAI) (e.g., of PLMN#1) as shown in Figure 8. V-SMF informs H-SMF of the target PLMN info or the (DNN, S-NSSAI) of the BH PDU session. If target PLMN info is provided, H-SMF then is able to select MWAB H-UPF to connect to PLMN#2 based on the target PLMN info. If the (DNN, S-NSSAI) of the BH PDU session is provided, H-SMF first maps the (DNN, S-NSSAI) into target PLMN info, then it is able to select MWAB H-UPF to connect to PLMN#2 based on the target PLMN info.

Figure 12 illustrates a flowchart of a method 1200 in accordance with aspects of the present disclosure. The operations of the method may be implemented by a network node (e.g., MWAB node) consisting of a gNB and a UE that are co-located as described herein. In some implementations, the UE may execute a set of instructions to control the function elements of the UE to perform the described functions.

At 1202, sending, to a session management function (SMF) of the second network, an establishment request for a Protocol Data Unit (PDU) session between the UE and a user plane function (UPF) of the second network along with first information associated with the first network, so that the gNB is capable of connecting to the first network.

Figure 13 illustrates a flowchart of a method 1300 in accordance with aspects of the present disclosure. The operations of the method may be implemented by a network node (e.g., SMF) of a second network as described herein. In some implementations, the network node may execute a set of instructions to control the function elements of the network node to perform the described functions.

At 1302, receiving, from a user equipment (UE) of a network node comprising the UE and a 5G Node-B (gNB) , an establishment request for a protocol data unit (PDU) session between the UE and a user plane function (UPF) of the second network, along with information associated with a first network to which the gNB of the network node is to be connected; and at 1304, selecting, based on at least the information associated with the first network, the UPF of the second network that is capable of connecting to the first network.

Figure 14 illustrates a flowchart of a method 1400 in accordance with aspects of the present disclosure. The operations of the method may be implemented by a network node (e.g., AMF) of a second network as described herein. In some implementations, the network node may execute a set of instructions to control the function elements of the network node to perform the described functions.

At 1402, receiving, from a user equipment (UE) of a network node comprising the UE and a 5G Node-B (gNB) , an establishment request for a protocol data unit (PDU) session between the UE and a user plane function (UPF) of the second network, along with first information associated with a first network to which the gNB of the network node is to be connected; and at 1404, sending, to a session management function (SMF) of the second network, the establishment request for the PDU session along with second information associated with the first network for the SMF to select the UPF that is capable of connecting to the first network, based on at least the second information associated with the first network.

It should be noted that the method described herein describes a possible implementation, and that the operations and the steps may be rearranged or otherwise modified and that other implementations are possible.

The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.

Claims

A network node, comprising a 5G Node-B (gNB) to be connected to a first network and a user equipment (UE) connected to a second network, wherein the UE comprises:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the UE to:

send, to a session management function (SMF) of the second network, an establishment request for a Protocol Data Unit (PDU) session between the UE and a user plane function (UPF) of the second network along with first information associated with the first network, so that the gNB is capable of connecting to the first network.
The network node of claim 1, wherein the first information associated with the first network comprises single network slice selection assistance information (S-NSSAI) or a combination of data network name (DNN) and S-NSSAI, of the second network.
The network node of claim 1, wherein the processor is further configured to cause the UE to

receive, from the gNB, second information associated with the first network.
The network node of claim 3, wherein the processor is further configured to cause the UE to

derive the first information associated with the first network from the second information associated with the first network.
The network node of claim 1, wherein the first information associated with the first network relates either to public land mobile network (PLMN) information of the first network, or to single network slice selection assistance information (S-NSSAI) , or a combination of data network name (DNN) and single network slice selection assistance information (S-NSSAI) , of the second network that can be mapped to the PLMN information of the first network.
The network node of claim 5, wherein the PLMN information of the first network includes at least one of PLMN ID and operations and management (OAM) information.
The network node of claim 6, wherein the OAM information of the first network includes at least one of internet protocol (IP) address, IP domain, and Fully Qualified Domain Name (FQDN) .
The network node of claim 4, wherein, the second information associated with the first network is either PLMN information of the first network, or S-NSSAI or a combination of DNN and S-NSSAI of the second network, that can be mapped to the PLMN information of the first network.
The network node of claim 8, wherein the mapping of the S-NSSAI, or the combination of DNN and S-NSSAI, of the second network to the PLMN information of the first network is based on UE Route Selection Policy (URSP) rule.
The network node of claim 1, wherein the at least one processor is configured to cause the UE to:

check whether the first network is the same as the second network, and

only when the first network is different from the second network, send the first information associated with the first network to the SMF of the second network.
A session management function (SMF) of a second network, comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the SMF to:

receive, from a user equipment (UE) of a network node comprising the UE and a 5G Node-B (gNB) , an establishment request for a protocol data unit (PDU) session between the UE and a user plane function (UPF) of the second network, along with information associated with a first network to which the gNB of the network node is to be connected; and

select, based on at least the information associated with the first network, the UPF of the second network that is capable of connecting to the first network.
The SMF of claim 11, wherein the information associated with the first network relates to S-NSSAI, or a combination of DNN and S-NSSAI, of the second network.
The SMF of claim 11, wherein the information associated with the first network relates to a public land mobile network (PLMN) information of the first network, or S-NSSAI, or a combination of DNN and S-NSSAI, of the second network that can be mapped to the PLMN information of the first network.
An access and mobility function (AMF) of a second network, comprising:

at least one memory; and

at least one processor coupled with the at least one memory and configured to cause the AMF to:

receive, from a user equipment (UE) of a network node comprising the UE and a 5G Node-B (gNB) , an establishment request for a protocol data unit (PDU) session between the UE and a user plane function (UPF) of the second network, along with first information associated with a first network to which the gNB of the network node is to be connected; and

send, to a session management function (SMF) of the second network, the establishment request for the PDU session along with second information associated with the first network for the SMF to select the UPF that is capable of connecting to the first network, based on at least the second information associated with the first network.
The AMF of claim 14, wherein the at least one processor is configured to cause the AMF to:

derive the second information associated with the first network from the first information associated with the first network.
The AMF of claim 14, wherein the first information associated with the first network relates to a public land mobile network (PLMN) information of the first network, or to S-NSSAI, or a combination of DNN and S-NSSAI, of the second network that can be mapped to the PLMN information of the first network.
The AMF of claim 14, wherein the first information associated with the first network is S-NSSAI, or a combination of DNN and S-NSSAI, of the second network.
The AMF of claim 14, wherein, the processor is further configured to cause the AMF to:

check whether the first network is the same as the second network; and

only when the first network is different from the second network, send the second information associated with the first network to the SMF of the second network along with the establishment request for the PDU session.