Communication related to dual registration

Abstract

One embodiment of the present specification provides a method by which an AMF performs communication. The method may comprise the steps of: receiving, from a UE, a registration request message including information related to dual registration; transmitting, to a UDM, a registration message including information related to the dual registration; receiving, from the UDM, a response message including information about whether the dual registration is permitted; and transmitting, to the UE, a registration response message including information about whether the dual registration is successful.

Description

Communication related to dual registration

[0001] This specification relates to mobile communications.

[0002] 3GPP (3rd Generation Partnership Project) LTE (Long-Term Evolution) is a technology designed to enable high-speed packet communications. Numerous approaches have been proposed to achieve LTE's goals of reducing costs for users and operators, improving service quality, expanding coverage, and increasing system capacity. 3GPP LTE's high-level requirements include reduced cost per bit, improved service availability, flexible use of frequency bands, a simple architecture, open interfaces, and adequate power consumption for terminals.

[0003] The International Telecommunication Union (ITU) and 3GPP have begun work on developing requirements and specifications for New Radio (NR) systems. 3GPP must identify and develop the technical components necessary to successfully standardize NR, meeting both urgent market needs and the longer-term requirements outlined by the ITU Radio communication sector (ITU-R) International Mobile Telecommunications (IMT)-2020 process. NR must also be able to utilize any spectrum band up to at least 100 GHz, ensuring that it remains available for wireless communications well into the future.

[0004] NR aims to be a single technology framework that addresses all deployment scenarios, usage scenarios, and requirements, including enhanced Mobile Broadband (eMBB), massive Machine Type Communications (mMTC), and Ultra-Reliable and Low Latency Communications (URLLC). NR must be inherently forward-compatible.

[0005] Dual registration, where a terminal registers via two 3GPP access points, is being discussed. However, prior art networks have a problem: they cannot support dual registration of terminals.

[0006] According to one embodiment of the present disclosure, a method for an AMF to perform communication is provided. The method may include the steps of: receiving a registration request message including information related to dual registration from a UE; transmitting a registration message including the information related to the dual registration to a UDM; receiving a response message from the UDM including information regarding whether the dual registration is permitted; and transmitting a registration response message including information regarding whether the dual registration is successful to the UE.

[0007] According to one embodiment, a device implementing the method is provided.

[0008] According to one embodiment of the present disclosure, a method for a UE to perform communication is provided. The method may include the steps of transmitting a registration request message including information related to dual registration to an AMF; and receiving a registration response message from the AMF including information regarding the success or failure of the dual registration.

[0009] According to one embodiment, a device implementing the method is provided.

[0010] According to one embodiment of the present disclosure, a method for a UDM to perform communication is provided. The method may include: receiving a first registration message related to a UE from a second AMF; receiving a second registration message from the second AMF, the second registration message including information related to dual registration for the UE; determining whether to allow the dual registration; and transmitting a response message to the second AMF, the response message including information regarding whether to allow the dual registration.

[0011] According to one embodiment, a device implementing the method is provided.

[0012] Figure 1 illustrates an example of a communication system to which the implementation of this specification is applied.

[0013] Figure 2 illustrates an example of a wireless device to which the implementation of the present specification is applied.

[0014] Figure 3 shows an example of a UE to which the implementation of this specification is applied.

[0015] Figure 4 shows an example of a 5G system structure to which the implementation of this specification is applied.

[0016] Figures 5 and 6 illustrate examples of registration procedures to which the implementation of the present specification applies.

[0017] Figure 7 is an example diagram showing an example of an architecture for implementing the concept of network slicing.

[0018] Figure 8 is an exemplary diagram showing another example of an architecture for implementing the concept of network slicing.

[0019] FIG. 9 illustrates an example of dual 5G satellite access according to one embodiment of the disclosure of the present specification.

[0020] FIG. 10 illustrates an example of traffic switching according to one embodiment of the disclosure of the present specification.

[0021] FIG. 11a illustrates a first example of multiple connections according to an embodiment of the disclosure of the present specification. FIG. 11b illustrates a second example of multiple connections according to an embodiment of the disclosure of the present specification. FIG. 11c illustrates a third example of multiple connections according to an embodiment of the disclosure of the present specification. FIG. 11d illustrates a fourth example of multiple connections according to an embodiment of the disclosure of the present specification.

[0022] FIG. 12 is an example of a single 3GPP access connection according to one embodiment of the disclosure of the present specification.

[0023] FIG. 13 is an example of a dual 3GPP access connection according to one embodiment of the disclosure of the present specification.

[0024] Figures 14a and 14b are a first example of a procedure according to the first example of the disclosure of the present specification.

[0025] Figure 15 is a second example of a procedure according to the first example of the disclosure of this specification.

[0026] Figure 16 is a first example of a procedure according to the fifth example of the disclosure of this specification.

[0027] Figure 17 is a second example of a procedure according to the fifth example of the disclosure of this specification.

[0028] FIG. 18 illustrates an example of operations according to one embodiment of the disclosure of the present specification.

[0029] The following techniques, devices, and systems can be applied to various wireless multiple access systems. Examples of multiple access systems include Code Division Multiple Access (CDMA) systems, Frequency Division Multiple Access (FDMA) systems, Time Division Multiple Access (TDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single Carrier Frequency Division Multiple Access (SC-FDMA) systems, and Multi-Carrier Frequency Division Multiple Access (MC-FDMA) systems. CDMA can be implemented using wireless technologies such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA can be implemented using wireless technologies such as Global System for Mobile communications (GSM), General Packet Radio Service (GPRS), or Enhanced Data rates for GSM Evolution (EDGE). OFDMA can be implemented using wireless technologies such as IEEE (Institute of Electrical and Electronics Engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, or Evolved UTRA (E-UTRA). UTRA is part of the Universal Mobile Telecommunications System (UMTS). 3GPP (3rd Generation Partnership Project) Long-Term Evolution (LTE) is part of E-UMTS (Evolved UMTS) that utilizes E-UTRA.3GPP LTE uses OFDMA in the downlink (DL) and SC-FDMA in the uplink (UL). Evolution of 3GPP LTE includes LTE-A (Advanced), LTE-A Pro, and / or 5G NR (New Radio).

[0030] For convenience of explanation, the implementation of this specification is primarily described in relation to a 3GPP-based wireless communication system. However, the technical features of this specification are not limited thereto. For example, the following detailed description is provided based on a mobile communication system corresponding to a 3GPP-based wireless communication system, but aspects of this specification that are not limited to a 3GPP-based wireless communication system can be applied to other mobile communication systems.

[0031] For terms and technologies used in this specification that are not specifically described, reference may be made to wireless communication standard documents published prior to this specification.

[0032] As used herein, "A or B" can mean "only A," "only B," or "both A and B." Alternatively, as used herein, "A or B" can be interpreted as "A and / or B." For example, as used herein, "A, B or C" can mean "only A," "only B," "only C," or "any combination of A, B and C."

[0033] As used herein, a slash ( / ) or a comma can mean "and / or." For example, "A / B" can mean "A and / or B." Accordingly, "A / B" can mean "only A," "only B," or "both A and B." For example, "A, B, C" can mean "A, B, or C."

[0034] In this specification, “at least one of A and B” may mean “only A,” “only B,” or “both A and B.” Additionally, in this specification, the expressions “at least one of A or B” or “at least one of A and / or B” may be interpreted identically to “at least one of A and B.”

[0035] Additionally, in this specification, “at least one of A, B and C” can mean “only A”, “only B”, “only C”, or “any combination of A, B and C”. Additionally, “at least one of A, B or C” or “at least one of A, B and / or C” can mean “at least one of A, B and C”.

[0036] Additionally, parentheses used herein may mean "for example." Specifically, when indicated as "control information (PDCCH)", "PDCCH" may be proposed as an example of "control information." In other words, "control information" in this specification is not limited to "PDCCH," and "PDCCH" may be proposed as an example of "control information." Furthermore, even when indicated as "control information (i.e., PDCCH)", "PDCCH" may be proposed as an example of "control information."

[0037] Technical features individually described in a single drawing in this specification may be implemented individually or simultaneously.

[0038] Although not limited thereto, the various descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein may be applied to various fields requiring wireless communication and / or connectivity between devices (e.g., 5G).

[0039] Hereinafter, the present specification will be described in more detail with reference to the drawings. In the following drawings and / or description, the same reference numbers may refer to the same or corresponding hardware blocks, software blocks, and / or functional blocks, unless otherwise indicated.

[0040] Figure 1 illustrates an example of a communication system to which the implementation of this specification is applied.

[0041] The 5G usage scenario shown in FIG. 1 is only an example, and the technical features of this specification can be applied to other 5G usage scenarios not shown in FIG. 1.

[0042] The three main requirement categories for 5G are (1) enhanced mobile broadband (eMBB), (2) massive machine type communication (mMTC), and (3) ultra-reliable and low latency communications (URLLC).

[0043] Referring to FIG. 1, a communication system (1) includes wireless devices (100a to 100f), a base station (BS; 200), and a network (300). FIG. 1 illustrates a 5G network as an example of a network of the communication system (1), but the implementation of the present disclosure is not limited to a 5G system and can be applied to future communication systems beyond the 5G system.

[0044] The base station (200) and the network (300) may be implemented as wireless devices, and a particular wireless device may operate as a base station / network node in relation to other wireless devices.

[0045] The wireless devices (100a to 100f) represent devices that perform communication using Radio Access Technology (RAT) (e.g., 5G NR or LTE) and may also be referred to as communication / wireless / 5G devices. The wireless devices (100a to 100f) may include, but are not limited to, a robot (100a), a vehicle (100b-1 and 100b-2), an extended reality (XR) device (100c), a portable device (100d), a home appliance (100e), an Internet-of-Things (IoT) device (100f), and an artificial intelligence (AI) device / server (400). For example, the vehicles may include vehicles having wireless communication capabilities, autonomous vehicles, and vehicles capable of performing vehicle-to-vehicle communication. The vehicles may include unmanned aerial vehicles (UAVs) (e.g., drones). XR devices may include AR (Augmented Reality) / VR (Virtual Reality) / MR (Mixed Reality) devices, and may be implemented in the form of HMD (Head-Mounted Device) and HUD (Head-Up Display) mounted on vehicles, televisions, smartphones, computers, wearable devices, home appliances, digital signs, vehicles, robots, etc. Portable devices may include smartphones, smart pads, wearable devices (e.g., smart watches or smart glasses), and computers (e.g., laptops). Home appliances may include TVs, refrigerators, and washing machines. IoT devices may include sensors and smart meters.

[0046] In this specification, wireless devices (100a to 100f) may be referred to as user equipment (UE). The UE may include, for example, a mobile phone, a smartphone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation system, a slate PC, a tablet PC, an ultrabook, a vehicle, a vehicle with autonomous driving function, a connected car, a UAV, an AI module, a robot, an AR device, a VR device, an MR device, a hologram device, a public safety device, an MTC device, an IoT device, a medical device, a fintech device (or a financial device), a security device, a weather / environmental device, a 5G service-related device, or a 4th industrial revolution-related device.

[0047] Wireless devices (100a to 100f) can be connected to a network (300) via a base station (200). AI technology can be applied to the wireless devices (100a to 100f), and the wireless devices (100a to 100f) can be connected to an AI server (400) via the network (300). The network (300) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, and a network after 5G. The wireless devices (100a to 100f) can communicate with each other via the base station (200) / network (300), but can also communicate directly (e.g., sidelink communication) without going through the base station (200) / network (300). For example, vehicles (100b-1, 100b-2) can communicate directly (e.g., vehicle-to-vehicle (V2V) / vehicle-to-everything (V2X) communication). Additionally, IoT devices (e.g., sensors) can communicate directly with other IoT devices (e.g., sensors) or other wireless devices (100a to 100f).

[0048] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (100a to 100f) and / or between wireless devices (100a to 100f) and a base station (200) and / or between base stations (200). Here, the wireless communication / connection can be established through various RATs (e.g., 5G NR), such as uplink / downlink communication (150a), sidelink communication (150b) (or, D2D (Device-To-Device) communication), and base station-to-base station communication (150c) (e.g., relay, IAB (Integrated Access and Backhaul)). Through the wireless communication / connection (150a, 150b, 150c), the wireless devices (100a to 100f) and the base station (200) can transmit / receive wireless signals to / from each other. For example, wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, at least some of the various configuration information setting processes for transmitting / receiving wireless signals, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), and resource allocation processes can be performed based on various proposals of the present specification.

[0049] NR supports multiple numerologies, or subcarrier spacings (SCS), to support diverse 5G services. For example, an SCS of 15 kHz supports wide areas in traditional cellular bands; an SCS of 30 kHz / 60 kHz supports dense urban areas, lower latency, and wider carrier bandwidth; and an SCS of 60 kHz or higher supports bandwidths greater than 24.25 GHz to overcome phase noise.

[0050] The NR frequency band can be defined by two types of frequency ranges (FR1 and FR2). The numerical values ​​of the frequency ranges can be changed. For example, the two types of frequency ranges (FR1 and FR2) can be as shown in Table 1 below. For convenience of explanation, among the frequency ranges used in the NR system, FR1 can mean the "sub 6 GHz range," and FR2 can mean the "above 6 GHz range," which can be called millimeter wave (mmW).

[0051] Frequency Range DefinitionFrequency RangeSubcarrier SpacingFR1450MHz - 6000MHz15, 30, 60kHzFR224250MHz - 52600MHz60, 120, 240kHz

[0052] As described above, the numerical value of the frequency range of the NR system can be changed. For example, FR1 may include a band from 410 MHz to 7125 MHz, as shown in Table 2 below. That is, FR1 may include frequency bands above 6 GHz (or 5850, 5900, 5925 MHz, etc.). For example, the frequency bands above 6 GHz (or 5850, 5900, 5925 MHz, etc.) included within FR1 may include unlicensed bands. Unlicensed bands may be used for various purposes, such as for communications for vehicles (e.g., autonomous driving).

[0053] Frequency Range DefinitionFrequency RangeSubcarrier SpacingFR1410MHz - 7125MHz15, 30, 60kHzFR224250MHz - 52600MHz60, 120, 240kHz

[0054] Here, the wireless communication technology implemented in the wireless device of the present specification may include not only LTE, NR, and 6G, but also Narrowband IoT (NB-IoT) for low-power communication. For example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology and may be implemented with standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the wireless device of the present specification may perform communication based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and may be called by various names such as eMTC (enhanced MTC). For example, LTE-M technology can be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (Non-Bandwidth Limited), 5) LTE-MTC, 6) LTE MTC, and / or 7) LTE M, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the wireless device of the present specification can include at least one of ZigBee, Bluetooth, and / or LPWAN considering low-power communication, and is not limited to the above-described names. For example, ZigBee technology can create PANs (Personal Area Networks) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and can be called by various names.

[0055] Figure 2 illustrates an example of a wireless device to which the implementation of the present specification is applied.

[0056] In FIG. 2, the first wireless device (100) and / or the second wireless device (200) may be implemented in various forms depending on the use case / service. For example, {the first wireless device (100) and the second wireless device (200)} may correspond to at least one of {the wireless devices (100a to 100f) and the base station (200)}, {the wireless devices (100a to 100f) and the wireless devices (100a to 100f)}, and / or {the base station (200) and the base station (200)} of FIG. 1. The first wireless device (100) and / or the second wireless device (200) may be configured by various components, devices / parts, and / or modules.

[0057] The first wireless device (100) may include at least one transceiver, such as a transceiver (106), at least one processing chip, such as a processing chip (101), and / or one or more antennas (108).

[0058] The processing chip (101) may include at least one processor, such as a processor (102), and at least one memory, such as a memory (104). Additionally and / or alternatively, the memory (104) may be located external to the processing chip (101).

[0059] The processor (102) may control the memory (104) and / or the transceiver (106) and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein. For example, the processor (102) may process information in the memory (104) to generate first information / signal and transmit a wireless signal including the first information / signal via the transceiver (106). The processor (102) may receive a wireless signal including second information / signal via the transceiver (106) and store information obtained by processing the second information / signal in the memory (104).

[0060] A memory (104) may be operatively connected to the processor (102). The memory (104) may store various types of information and / or instructions. The memory (104) may store firmware and / or software code (105) that implements code, instructions and / or sets of instructions that, when executed by the processor (102), perform the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed herein. For example, the firmware and / or software code (105) may implement instructions that, when executed by the processor (102), perform the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed herein. For example, the firmware and / or software code (105) may control the processor (102) to perform one or more protocols. For example, the firmware and / or software code (105) may control the processor (102) to perform one or more air interface protocol layers.

[0061] Here, the processor (102) and memory (104) may be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). A transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals via one or more antennas (108). Each transceiver (106) may include a transmitter and / or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present specification, the first wireless device (100) may represent a communication modem / circuit / chip.

[0062] The second wireless device (200) may include at least one transceiver, such as a transceiver (206), at least one processing chip, such as a processing chip (201), and / or one or more antennas (208).

[0063] The processing chip (201) may include at least one processor, such as a processor (202), and at least one memory, such as a memory (204). Additionally and / or alternatively, the memory (204) may be located external to the processing chip (201).

[0064] The processor (202) may control the memory (204) and / or the transceiver (206) and may be configured to implement the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein. For example, the processor (202) may process information in the memory (204) to generate third information / signal and transmit a wireless signal including the third information / signal via the transceiver (206). The processor (202) may receive a wireless signal including fourth information / signal via the transceiver (206) and store information obtained by processing the fourth information / signal in the memory (204).

[0065] A memory (204) may be operatively connected to the processor (202). The memory (204) may store various types of information and / or instructions. The memory (204) may store firmware and / or software code (205) that implements code, instructions and / or sets of instructions that, when executed by the processor (202), perform the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed herein. For example, the firmware and / or software code (205) may implement instructions that, when executed by the processor (202), perform the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed herein. For example, the firmware and / or software code (205) may control the processor (202) to perform one or more protocols. For example, the firmware and / or software code (205) may control the processor (202) to perform one or more air interface protocol layers.

[0066] Here, the processor (202) and memory (204) may be part of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). A transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via one or more antennas (208). Each transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with the RF unit. In the present specification, the second wireless device (200) may represent a communication modem / circuit / chip.

[0067] Hereinafter, hardware elements of the wireless device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as a physical (PHY) layer, a Media Access Control (MAC) layer, a Radio Link Control (RLC) layer, a Packet Data Convergence Protocol (PDCP) layer, a Radio Resource Control (RRC) layer, and a Service Data Adaptation Protocol (SDAP) layer). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs), one or more Service Data Units (SDUs), messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein.

[0068] The one or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, and / or a microcomputer. The one or more processors (102, 202) may be implemented by hardware, firmware, software, and / or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), and / or one or more Field Programmable Gate Arrays (FPGAs) may be included in the one or more processors (102, 202). For example, the one or more processors (102, 202) may be configured by a set of a communication control processor, an Application Processor (AP), an Electronic Control Unit (ECU), a Central Processing Unit (CPU), a Graphic Processing Unit (GPU), and a Memory Control Processor. One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions and / or commands. The one or more memories (104, 204) may be configured as random access memory (RAM), dynamic RAM (DRAM), read-only memory (ROM), erasable programmable ROM (EPROM), flash memory, volatile memory, nonvolatile memory, hard drive, register, cache memory, computer readable storage media and / or combinations thereof.One or more memories (104, 204) may be located internally and / or externally to one or more processors (102, 202). Additionally, one or more memories (104, 204) may be connected to one or more processors (102, 202) via various technologies, such as wired or wireless connections.

[0069] One or more transceivers (106, 206) can transmit user data, control information, wireless signals / channels, etc., referred to in the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals / channels, etc., referred to in the descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed herein from one or more other devices. For example, one or more transceivers (106, 206) can be coupled to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, wireless signals, etc., to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, wireless signals, etc. from one or more other devices.

[0070] One or more transceivers (106, 206) may be coupled to one or more antennas (108, 208). Additionally and / or alternatively, one or more transceivers (106, 206) may include one or more antennas (108, 208). One or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals / channels, etc., as described in the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein via one or more antennas (108, 208). In the present disclosure, one or more antennas (108, 208) may be multiple physical antennas or multiple logical antennas (e.g., antenna ports).

[0071] One or more transceivers (106, 206) may convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using one or more processors (102, 202). One or more transceivers (106, 206) may convert processed user data, control information, wireless signals / channels, etc. from baseband signals to RF band signals using one or more processors (102, 202). For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or a filter. For example, one or more transceivers (106, 206) may up-convert an OFDM baseband signal to an OFDM signal via an (analog) oscillator and / or filter under the control of one or more processors (102, 202) and transmit the up-converted OFDM signal at a carrier frequency. One or more transceivers (106, 206) may receive an OFDM signal at a carrier frequency and down-convert the OFDM signal to an OFDM baseband signal via an (analog) oscillator and / or filter under the control of one or more processors (102, 202).

[0072] Although not illustrated in FIG. 2, the wireless device (100, 200) may further include additional components. The additional components (140) may be configured in various ways depending on the type of the wireless device (100, 200). For example, the additional components (140) may include at least one of a power unit / battery, an input / output (I / O) device (e.g., an audio I / O port, a video I / O port), a driving device, and a computing device. The additional components (140) may be connected to one or more processors (102, 202) via various technologies, such as a wired or wireless connection.

[0073] In the implementation of this specification, a UE can operate as a transmitter in the uplink and as a receiver in the downlink. In the implementation of this specification, a base station can operate as a receiver in the UL and as a transmitter in the DL. For the sake of convenience of description, it is mainly assumed below that the first wireless device (100) operates as a UE and the second wireless device (200) operates as a base station. For example, a processor (102) connected to, mounted on, or released in the first wireless device (100) can be configured to perform UE operations according to the implementation of this specification or to control a transceiver (106) to perform UE operations according to the implementation of this specification. A processor (202) connected to, mounted on, or released in the second wireless device (200) can be configured to perform base station operations according to the implementation of this specification or to control a transceiver (206) to perform base station operations according to the implementation of this specification.

[0074] In this specification, a base station may be referred to as a Node B, an eNode B (eNB), or a gNB.

[0075] Figure 3 shows an example of a UE to which the implementation of this specification is applied.

[0076] Referring to FIG. 3, the UE (100) can correspond to the first wireless device (100) of FIG. 2.

[0077] The UE (100) includes a processor (102), memory (104), a transceiver (106), one or more antennas (108), a power management module (141), a battery (142), a display (143), a keypad (144), a SIM (Subscriber Identification Module) card (145), a speaker (146), and a microphone (147).

[0078] The processor (102) may be configured to implement the descriptions, functions, procedures, proposals, methods and / or flowcharts disclosed herein. The processor (102) may be configured to control one or more other components of the UE (100) to implement the descriptions, functions, procedures, proposals, methods and / or flowcharts disclosed herein. A layer of a radio interface protocol may be implemented in the processor (102). The processor (102) may include an ASIC, other chipsets, logic circuits and / or data processing devices. The processor (102) may be an application processor. The processor (102) may include at least one of a DSP, a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), and a modem (modulator and demodulator). An example of the processor (102) is the SNAPDRAGON manufactured by Qualcomm®. TM Series processors, EXYNOS made by Samsung® TM Series processors, A-series processors made by Apple®, HELIO made by MediaTek® TM ATOM series processors made by Intel® TM It can be found in the series processors or the corresponding next-generation processors.

[0079] Memory (104) is operatively coupled to the processor (102) and stores various information for operating the processor (102). Memory (104) may include ROM, RAM, flash memory, memory cards, storage media, and / or other storage devices. When the implementation is implemented in software, the techniques described herein may be implemented using modules (e.g., procedures, functions, etc.) that perform the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed herein. The modules may be stored in memory (104) and executed by the processor (102). Memory (104) may be implemented within the processor (102) or external to the processor (102), in which case it may be communicatively coupled to the processor (102) via various methods known in the art.

[0080] A transceiver (106) is operably coupled to the processor (102) and transmits and / or receives a radio signal. The transceiver (106) includes a transmitter and a receiver. The transceiver (106) may include a baseband circuit for processing a radio frequency signal. The transceiver (106) controls one or more antennas (108) to transmit and / or receive a radio signal.

[0081] The power management module (141) manages the power of the processor (102) and / or the transceiver (106). The battery (142) supplies power to the power management module (141).

[0082] The display (143) outputs the results processed by the processor (102). The keypad (144) receives input to be used by the processor (102). The keypad (144) can be displayed on the display (143).

[0083] A SIM card (145) is an integrated circuit that securely stores an International Mobile Subscriber Identity (IMSI) and associated keys, and is used to identify and authenticate subscribers in mobile devices such as mobile phones and computers. Additionally, many SIM cards can store contact information.

[0084] The speaker (146) outputs sound-related results processed by the processor (102). The microphone (147) receives sound-related input to be used by the processor (102).

[0085] Figure 4 shows an example of a 5G system structure to which the implementation of this specification is applied.

[0086] The 5G system (5GS; 5G system) structure consists of the following network functions (NF; Network Function).

[0087] - AUSF (Authentication Server Function)

[0088] -AMF (Access and Mobility Management Function)

[0089] - DN (Data Network), for example, operator services, Internet access, or third-party services.

[0090] - USDF (Unstructured Data Storage Function)

[0091] - NEF (Network Exposure Function)

[0092] - I-NEF (Intermediate NEF)

[0093] - NRF (Network Repository Function)

[0094] - NSSF (Network Slice Selection Function)

[0095] - PCF (Policy Control Function)

[0096] - SMF (Session Management Function)

[0097] - UDM (Unified Data Management)

[0098] - UDR (Unified Data Repository)

[0099] - UPF (User Plane Function)

[0100] - UCMF (UE radio Capability Management Function)

[0101] - AF (Application Function)

[0102] - UE (User Equipment)

[0103] - (R)AN ((Radio) Access Network)

[0104] - 5G-EIR (5G-Equipment Identity Register)

[0105] - NWDAF (Network Data Analytics Function)

[0106] - CHF (CHarging Function)

[0107] 또한, 다음과 같은 네트워크 기능이 고려될 수 있다.

[0108] - N3IWF (Non-3GPP InterWorking Function)

[0109] - TNGF (Trusted Non-3GPP Gateway Function)

[0110] - W-AGF (Wireline Access Gateway Function)

[0111] Figure 4 illustrates the 5G system architecture for a non-roaming case using a reference point representation showing how various network functions interact with each other.

[0112] For clarity of the point-to-point diagram in Figure 4, UDSF, NEF, and NRF are not illustrated. However, all network functions shown can interact with UDSF, UDR, NEF, and NRF as needed.

[0113] For clarity, the connection between UDR and other NFs (e.g., PCF) is not shown in Fig. 4. For clarity, the connection between NWDAF and other NFs (e.g., PCF) is not shown in Fig. 4.

[0114] The 5G system architecture includes the following benchmarks:

[0115] - N1: Reference point between UE and AMF.

[0116] - N2: Reference point between (R)AN and AMF.

[0117] - N3: Reference point between (R)AN and UPF.

[0118] - N4: Reference point between SMF and UPF.

[0119] - N6: Reference point between UPF and data network.

[0120] - N9: Reference point between two UPFs.

[0121] The following benchmarks illustrate the interactions that exist between NF services in NF.

[0122] - N5: Reference point between PCF and AF.

[0123] - N7: Reference point between SMF and PCF.

[0124] - N8: Reference point between UDM and AMF.

[0125] - N10: Reference point between UDM and SMF.

[0126] - N11: Reference point between AMF and SMF.

[0127] - N12: Reference point between AMF and AUSF.

[0128] - N13: Reference point between UDM and AUSF.

[0129] - N14: Reference point between two AMFs.

[0130] - N15: Reference point between PCF and AMF for non-roaming scenarios, and reference point between PCF and AMF of visited network for roaming scenarios.

[0131] - N16: Reference point between two SMFs (in case of roaming, between the SMF of the visited network and the SMF of the home network)

[0132] - N22: Reference point between AMF and NSSF.

[0133] In some cases, two NFs may need to be interconnected to serve a UE.

[0134] Describes the registration procedure. See section 4.2.2.2 of 3GPP TS 23.502 V16.3.0 (2019-12).

[0135] Figures 5 and 6 illustrate examples of registration procedures to which the implementation of the present specification applies.

[0136] A UE must register with the network to receive services, enable mobility tracking, and enable reachability. The UE initiates the registration process using one of the following registration types:

[0137] - Initial registration for 5GS; or

[0138] - mobility registration update; or

[0139] - Periodic registration update; or

[0140] - Emergency registration

[0141] The general registration procedures of Figures 5 and 6 apply to all registration procedures described above, but periodic registration updates do not need to include all parameters used in other registration procedures.

[0142] The general registration procedures of Figures 5 and 6 can also be used to register a UE for a 3GPP connection when it is already registered for a non-3GPP connection, and vice versa. Registering a UE for a 3GPP connection when it is already registered for a non-3GPP connection scenario may require an AMF change.

[0143] First, the procedure of Fig. 5 is described.

[0144] (1) Step 1: The UE transmits a Registration Request message to the (R)AN. The Registration Request message corresponds to an AN message.

[0145] The registration request message may include AN parameters. For NG-RAN, the AN parameters include, for example, the 5G SAE temporary mobile subscriber identity (5G-S-TMSI) or globally unique AMF ID (GUAMI), the selected public land mobile network (PLMN) ID (or PLMN ID and network identifier (NID)), and the requested network slice selection assistance information (NSSAI). The AN parameters also include an establishment cause. The establishment cause provides the reason for requesting establishment of an RRC connection. Whether and how the UE includes the requested NSSAI as part of the AN parameters depends on the value of the access stratum connection establishment NSSAI inclusion mode parameter.

[0146] A registration request message may include a registration type. The registration type indicates whether the UE wants to perform an initial registration (i.e., the UE is in RM-DEREGISTERED state), or a mobility registration update (i.e., the UE is in RM-REGISTERED state and the registration procedure is initiated because the UE moves, or the UE wants to update its capabilities or protocol parameters, or because the UE requests a change in the set of network slices it is allowed to use), or a periodic registration update (i.e., the UE is in RM-REGISTERED state and the registration procedure is initiated because the periodic registration update timer has expired), or an emergency registration (i.e., the UE is in restricted service state).

[0147] When a UE performs initial registration, the UE indicates its UE ID in the registration request message, listed in decreasing priority order.

[0148] i) If the UE has a valid evolved packet system (EPS) globally unique temporary identifier (GUTI), 5G-GUTI mapped from the EPS GUTI;

[0149] ii) Native 5G-GUTI (if available) allocated by the PLMN in which the UE is attempting to register;

[0150] iii) Native 5G-GUTI allocated by a PLMN equivalent to the PLMN in which the UE is attempting to register;

[0151] iv) Native 5G-GUTI allocated by another PLMN (if available);

[0152] v) Otherwise, the UE includes a subscriber concealed identifier (SUCI) in the registration request message.

[0153] If a UE performing initial registration has both a valid EPS GUTI and a native 5G-GUTI, the UE also indicates the native 5G-GUTI as an additional GUTI. If more than one native 5G-GUTI is available, the UE selects a 5G-GUTI from items (ii)-(iv) in decreasing priority order in the list above.

[0154] When the UE performs initial registration with native 5G-GUTI, the UE indicates the relevant GUAMI information in the AN parameters. When the UE performs initial registration with SUCI, the UE does not indicate the GUAMI information in the AN parameters.

[0155] For emergency registration, if the UE does not have a valid 5G-GUTI, the SUCI is included. If the UE does not have a subscriber permanent identifier (SUPI) and does not have a valid 5G-GUTI, the PEI (Permanent Equipment Identifier) ​​is included. Otherwise, the 5G-GUTI is included, indicating the last serving AMF.

[0156] The registration request message may also include security parameters, PDU session status, etc. Security parameters are used for authentication and integrity protection. The PDU session status indicates a previously established PDU session in the UE. When the UE is connected to two AMFs belonging to different PLMNs via a 3GPP connection and a non-3GPP connection, the PDU session status indicates the PDU session currently established in the PLMN in the UE.

[0157] (2) Step 2: (R)AN selects AMF.

[0158] If 5G-S-TMSI or GUAMI is not included, or if 5G-S-TMSI or GUAMI does not indicate a valid AMF, the (R)AN selects an AMF based on the (R)AT and the requested NSSAI, if available.

[0159] When the UE is in CM-CONNECTED state, (R)AN can forward a registration request message to AMF based on the UE's N2 connection.

[0160] If the (R)AN cannot select an appropriate AMF, the (R)AN performs AMF selection by forwarding a registration request message to the AMF configured in the (R)AN.

[0161] (3) Step 3: (R)AN sends a registration request message to the new AMF. The registration request message corresponds to the N2 message.

[0162] The registration request message may contain all of the information and / or part of the information contained in the registration request message received from the UE described in step 1.

[0163] The registration request message may include an N2 parameter. When NG-RAN is used, the N2 parameter includes the selected PLMN ID (or PLMN ID and NID), location information and cell ID related to the cell where the UE is camping, and a UE context request indicating that a UE context including security information should be established in the NG-RAN. When NG-RAN is used, the N2 parameter also includes an establishment cause.

[0164] If the registration type indicated by the UE is periodic registration update, steps 4-19 described below may be omitted.

[0165] (4) Step 4: If the UE's 5G-GUTI is included in the registration request message and the serving AMF has changed since the last registration procedure, the new AMF may invoke the Namf_Communication_UEContextTransfer service operation to the previous AMF, including the full registration request non-access stratum (NAS) message to request the UE's SUPI and UE context.

[0166] (5) Step 5: The old AMF can respond to the new AMF for the Namf_Communication_UEContextTransfer call including the UE's SUPI and UE context.

[0167] (6) Step 6: If SUCI is not provided by the UE or not retrieved from the previous AMF, the new AMF may initiate an ID request procedure by sending an Identity Request message to request SUCI from the UE.

[0168] (7) Step 7: The UE may respond with an Identity Response message including the SUCI. The UE derives the SUCI using the provided public key of the home PLMN (HPLMN).

[0169] (8) Step 8: The new AMF may decide to initiate UE authentication by calling the AUSF. In this case, the new AMF selects the AUSF based on SUPI or SUCI.

[0170] (9) Step 9: Authentication / security can be established by UE, new AMF, AUSF and / or UDM.

[0171] (10) Step 10: If the AMF has changed, the new AMF may call the Namf_Communication_RegistrationCompleteNotify service operation to notify the old AMF that the UE registration with the new AMF is complete. If the authentication / security procedure fails, the registration is rejected and the new AMF may call the Namf_Communication_RegistrationCompleteNotify service operation with a reject indication reason code to the old AMF. The old AMF may continue as if the UE context transfer service operation was not received.

[0172] (11) Step 11: If the PEI was not provided by the UE or was not retrieved from the previous AMF, the new AMF may initiate the ID request procedure by sending an Identity Request message to the UE to retrieve the PEI. The PEI is transmitted encrypted, except when the UE performs emergency registration and cannot be authenticated.

[0173] (12) Step 12: Optionally, the new AMF can initiate ME ID checking by calling the N5g-eir_EquipmentIdentityCheck_Get service operation.

[0174] Now, the procedure of Fig. 6 following the procedure of Fig. 5 is described.

[0175] (13) Step 13: When step 14 below is performed, the new AMF can select a UDM based on SUPI, and the UDM can select a UDR instance.

[0176] (14) Step 14: New AMFs can be registered with UDM.

[0177] (15) Step 15: New AMF can select PCF.

[0178] (16) Step 16: The new AMF may optionally perform AM policy association establishment / modification.

[0179] (17) Step 17: The new AMF can send update / release SM context messages (e.g., Nsmf_PDUSession_UpdateSMContext and / or Nsmf_PDUSession_ReleaseSMContext) to the SMF.

[0180] (18) Step 18: If the new AMF and the old AMF are in the same PLMN, the new AMF may send a UE context modification request to the N3IWF / TNGF / W-AGF.

[0181] (19) Step 19: N3IWF / TNGF / W-AGF may send a UE context modification response to the new AMF.

[0182] (20) Step 20: After the new AMF receives the response message from N3IWF / TNGF / W-AGF in step 19, the new AMF can register with UDM.

[0183] (21) Step 21: The new AMF sends a Registration Accept message to the UE.

[0184] The new AMF sends the UE a Registration Accept message indicating that the registration request has been accepted. If the new AMF allocates a new 5G-GUTI, it includes the 5G-GUTI. If the UE is already in the RM-REGISTERED state through another connection to the same PLMN, the UE uses the 5G-GUTI received in the Registration Accept message for both registrations. If the Registration Accept message does not include a 5G-GUTI, the UE uses the 5G-GUTI assigned to the existing registration for the new registration. If the new AMF allocates a new registration area, it sends the registration area to the UE in the Registration Accept message. If the Registration Accept message does not include a registration area, the UE considers the previous registration area to be valid. Mobility Restrictions are included if mobility restrictions apply to the UE and the registration type is not emergency registration. The new AMF indicates the PDU sessions established for the UE in the PDU Session State. The UE locally removes internal resources associated with PDU sessions that are not marked as established in the received PDU Session State. When a UE is connected to two AMFs belonging to different PLMNs via a 3GPP connection and a non-3GPP connection, the UE locally removes internal resources associated with PDU sessions in the current PLMN that are not marked as established in the received PDU session status. If PDU session status information is present in the Registration Accept message, the new AMF indicates the PDU session status to the UE.

[0185] The Allowed NSSAI provided in the Registration Accept message is valid for the registration area and applies to all PLMNs that have a tracking area included in the registration area. The Mapping of Allowed NSSAIs maps HPLMN S-NSSAIs to each S-NSSAI of the Allowed NSSAIs. The Mapping of Configured NSSAIs maps HPLMN S-NSSAIs to each S-NSSAI of the Configured NSSAI for the serving PLMN.

[0186] Additionally, optionally, the new AMF performs UE policy association establishment.

[0187] (22) Step 22: If the UE successfully updates itself, it can send a Registration Complete message to the new AMF.

[0188] The UE may send a registration complete message to the new AMF to confirm that a new 5G-GUTI has been allocated.

[0189] (23) Step 23: In case of registration via 3GPP connection, if the new AMF does not release the signaling connection, the new AMF may send RRC Inactive Assistance information to the NG-RAN. In case of registration via non-3GPP connection, if the UE is in CM-CONTENED state on the 3GPP connection, the new AMF may send RRC Inactive Assistance information to the NG-RAN.

[0190] (24) Step 24: AMF can perform information updates on UDM.

[0191] (25) Step 25: The UE may execute a network slice-specific authentication and authorization (NSSAA) procedure.

[0192] Network Slice

[0193] Below, we explain network slicing to be introduced in next-generation mobile communications.

[0194] Next-generation mobile communications introduce the concept of network slicing to provide diverse services through a single network. Here, a network slicing refers to a combination of network nodes with the functions necessary to provide a specific service. The network nodes that make up a slice instance can be either hardware-independent or logically independent.

[0195] Each slice instance can be composed of any combination of nodes required to form the entire network. In this case, a single slice instance can provide services to a UE independently.

[0196] Alternatively, a slice instance may be composed of a combination of nodes within the network. In this case, the slice instance may not provide services to the UE independently, but may instead collaborate with other existing network nodes to provide services to the UE. Furthermore, multiple slice instances may collaborate to provide services to the UE.

[0197] Slice instances differ from dedicated core networks in that the entire network, including the core network (CN) nodes and the RAN, can be separated. Furthermore, slice instances differ from dedicated core networks in that network nodes can be logically separated.

[0198] Note that for network slices, quotas can be used.

[0199] For example, a quota associated with a network slice may include a quota for a maximum number of UEs. The quota for the maximum number of UEs may refer to the maximum number of terminals that can simultaneously use the network slice. For example, each network slice information may include quota information for a maximum number of UEs (e.g., 10, 1,000,000, etc.).

[0200] For example, a quota associated with a network slice may include a quota for the maximum number of PDU sessions. The quota for the maximum number of PDU sessions may refer to the maximum number of concurrent PDU sessions supported by the network slice. For example, the maximum number of concurrent PDU sessions supported by the network slice may refer to the maximum number of PDU sessions that can be simultaneously established within a network slice associated with a Data Network Name (DNN) defined by the S-NSSAI.

[0201] In 5G mobile communications, network slice quota event notifications may be supported within a network slice. For example, event notifications regarding quotas related to a network slice may be supported. For example, an AF may request an event notification regarding quotas related to a network slice from 5GS. Then, the AF may receive quota notifications for attributes related to the network slice from 5GS. For example, the 5GS may notify the AF whether the quota for a specific attribute has reached a specified threshold. Then, the AF may influence 5GS routing decisions.

[0202] Figure 7 is an example diagram showing an example of an architecture for implementing the concept of network slicing.

[0203] As can be seen from Figure 7, a core network (CN) can be divided into multiple slice instances. Each slice instance can include one or more CP functional nodes and UP functional nodes.

[0204] Each UE can use a network slice instance suitable for its service through the RAN.

[0205] Unlike the example shown in FIG. 7, each slice instance may share one or more of the CP function nodes and UP function nodes with other slice instances. This is described below with reference to FIG. 8.

[0206] Figure 8 is an exemplary diagram showing another example of an architecture for implementing the concept of network slicing.

[0207] Referring to FIG. 8, multiple UP function nodes are clustered, and similarly multiple CP function nodes are clustered.

[0208] And, referring to FIG. 8, slice instance #1 (or referred to as instance #1) within the core network includes a first cluster of UP functional nodes. And, the slice instance #1 shares a cluster of CP functional nodes with slice #2 (or referred to as instance #2). The slice instance #2 includes a second cluster of UP functional nodes.

[0209] The illustrated NSSF selects a slice (or instance) that can accommodate the UE's service.

[0210] The illustrated UE can use service #1 through slice instance #1 selected by the NSSF, and can also use service #2 through slice instance #2 selected by the N.

[0211] In 3GPP, a study called FS_DualSteer (Study on Upper layer traffic steering, switching, and split over dual 3GPP access - SP-220445) is being discussed. Dual Steer can include use cases and service requirements related to steering, splitting, and switching UE traffic over two 3GPP access links, for example. Specifically, the study is being conducted for the following objectives. For examples of use cases and service requirements, please refer to TR 22.841 V1.1.0 "Study on Upper layer traffic steer, switch, and split over dual 3GPP access."

[0212] Examples of Objectives related to dual steering include:

[0213] Additional use cases and potential service requirements that could benefit from UE traffic support for higher layer steering, split and switching (e.g., related to the same data session) in 5GS are studied, assuming only a single subscription to two 3GPP access links, including the following scenarios:

[0214] - Single PLMN, PLMN plus (standalone) NPN, 2 PLMNs

[0215] - Same or different 3GPP RAT (add NR or NTN, or NR, NTN, or LTE)

[0216] Note: NTN can refer to NR-based satellite access, including various orbits (e.g., GEO / MEO / LEO), which stand for Geostationary Earth Orbit (GEO), Medium Earth Orbit (MEO), and Low Earth Orbit (LEO), respectively.

[0217] For the PLMN plus PLMN / NPN scenario, the two networks can be managed by the same operator or by different operators (assuming there is a business agreement between the operators).

[0218] The study related to dual steering includes a gap analysis regarding the support of use cases identified by existing service requirements and functions, including the potential applicability of existing multi-NW requirements (e.g., TS 22.261 V19.3.0 Sections 6.1, 6.3, 6.18, 6.41).

[0219] An example use case for TR 22.841 V1.1.0 is as follows:

[0220] Describes an example of a dual 5G satellite access use case in a maritime scenario.

[0221] This use case describes a scenario where an autonomous ship is remotely controlled from shore. The ship has UEs served by two satellite RANs (GEO and LEO) belonging to the same PLMN managed by a 5G satellite operator. The ship's UEs have a single PLMN subscription.

[0222] Dual 5G satellite access will be deployed to accommodate the massive data traffic for remote control operations. To improve the performance of autonomous ship operations, delay-sensitive applications (e.g., remote control operations, collision / accident prevention, emergency management, etc.) will utilize LEO satellite links, which have lower UE-to-ground propagation delays than GEO satellite links (LEO up to 30 ms vs. GEO up to 280 ms, TS 22.261 V19.3.0, Section 7.4.1). Other delay-sensitive applications (e.g., sensor data monitoring, video surveillance, etc.) can utilize GEO satellite links or aggregate traffic across both accesses.

[0223] The following prerequisites may apply for this use case:

[0224] An example of an autonomous ship is the Korean Autonomous Surface Ship (KASS). This autonomous ship can support dual 5G satellite connectivity (GEO and LEO).

[0225] UEs installed on autonomous ships have subscriptions to use GEO and LEO satellite services from 5G satellite operators.

[0226] UEs installed on autonomous ships register and connect to GEO and LEO satellite RANs.

[0227] According to the service agreement between the autonomous vessel management company and the 5G satellite operator, the 5G satellite network has the following policies for the autonomous vessel's UE:

[0228] - Data traffic for latency-sensitive applications is routed over LEO satellite links whenever available.

[0229] - Data traffic for delay-tolerant applications is aggregated across LEO and GEO satellite links.

[0230] For use cases related to autonomous ships, a service flow like the example below can be applied.

[0231] Referring to FIG. 9, a specific example of dual 5G satellite access in autonomous vessel operation is illustrated.

[0232] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0233] FIG. 9 illustrates an example of dual 5G satellite access according to one embodiment of the disclosure of the present specification.

[0234] 1. The autonomous vessel is at sea and can be remotely controlled by a shore control center. The autonomous vessel can have two active data sessions: one for remote control operations and one for sensor data monitoring. According to agreed-upon policies, remote control operation traffic (e.g., delay-sensitive traffic) is routed via LEO satellite links, while sensor data monitoring traffic (e.g., delay-tolerant traffic) is aggregated across LEO and GEO satellite links.

[0235] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0236] FIG. 10 illustrates an example of traffic switching according to one embodiment of the disclosure of the present specification.

[0237] The example in Figure 10 illustrates an example of traffic diversion due to a loss of connection with a LEO satellite access network.

[0238] 2. If LEO satellite access becomes unavailable (e.g., due to loss of line of sight between the UE and the satellite), all traffic routed via LEO satellite access will be shifted to GEO satellite access while maintaining data session continuity. Applications for ship remote control (delay-sensitive) will detect increased communication latency and adjust their operations accordingly.

[0239] 3. After a while, LEO satellite access becomes available again. Therefore, the traffic distribution between the two satellite accesses returns to the same state as in Step 1.

[0240] The postconditions are as follows: the remote control center controls the autonomous ship throughout the route, and the autonomous ship successfully reaches its destination.

[0241] Describes an example of an existing feature that encompasses some or all of the use case functionality.

[0242] The ATSSS feature specified in TS 23.501 V17.2.2 section 5.32 supports dual user plane connectivity between the UE and the data network using one 3GPP access network and one non-3GPP access network.

[0243] 5G systems should be able to dynamically offload portions of traffic based on operator policies, taking into account traffic load and traffic type (e.g., offloading from 3GPP RATs to non-3GPP access technologies).

[0244] Depending on operator policy, 5G systems must be able to provide simultaneous data transmission over different access technologies (e.g., NR, E-UTRA, non-3GPP) to access one or more 3GPP services.

[0245] When a UE uses two or more access technologies simultaneously, the 5G system must be able to optimally distribute user traffic by selecting one of the access technologies in use, taking into account the service, traffic characteristics, radio characteristics, and the UE's movement speed.

[0246] 5G systems must support UEs with multi-radio and single-radio capabilities.

[0247] 5G systems must be able to provide services using satellite access.

[0248] A 5G system capable of satellite access must support a variety of configurations where the radio access network is a satellite NG-RAN, a non-3GPP satellite access network, or both.

[0249] Potential new requirements needed to support use cases could include, for example: The 5G system must support mechanisms to steer, split, and switch user plane traffic across two 5G satellite access networks belonging to the same PLMN, with the user plane traffic anchored to the 5GC.

[0250] A use case for NTN-based dual 3GPP access is described.

[0251] By integrating two 3GPP access links simultaneously, one of which is a non-terrestrial network, the following 5G services can be provided. This could be particularly useful in remote areas where bandwidth is limited or access links are unreliable:

[0252] - Expanded mobile broadband

[0253] - Ultra Reliable Service Communication

[0254] Several service scenarios (e.g., residential users in remote areas, users on vehicles, high-speed trains, ships, or airplanes) may benefit from combining terrestrial and non-terrestrial access, or combining two types of non-terrestrial access (e.g., based on GSO and NGSO), to meet target service performance in terms of data rate and / or reliability.

[0255] In areas where service is unavailable, the bandwidth provided by terrestrial-based access (e.g., NR or LTE) may be limited at the cell edge. Adding NTN-based NG-RAN can help achieve the desired perceived data rates.

[0256] In some scenarios, such as on high-speed trains, the service area may not be completely uniform along the track, and the targeted reliability can be provided through multiple connections including NTN-based NG-RAN.

[0257] Therefore, one UE can be connected and served simultaneously by the following examples:

[0258] - One NTN-based 3GPP access and one terrestrial-based 3GPP access

[0259] - One NTN-based 3GPP access (NGSO) and another NTN-based 3GPP access (GSO).

[0260] - One NTN-based 3GPP access (NGSO) via two different satellites of the same constellation.

[0261] Dual access bonding can occur on the uplink, downlink, or both.

[0262] The same or different gNBs can serve NR cells via terrestrial access networks and satellite access networks (e.g., transparent payloads from onboard satellites).

[0263] NTN-based NG-RAN can refer to transparent payload satellites as well as regenerative payload satellites equipped with, for example, some gNB functionality.

[0264] Referring to the following Figures 11a to 11d, examples of a) to d) are described.

[0265] a) Multi-connectivity including transparent payload NTN-based NG-RAN and terrestrial NG-RAN;

[0266] The UE connects to the 5GCN simultaneously via two access points (e.g., a transparent NTN-based NG-RAN and a cellular NG-RAN). It is assumed that the NTN gateway is located in the PLMN area of ​​the cellular access network.

[0267] Referring to the examples of FIGS. 11a and 11b, an example of multi-connectivity including a transparent payload NTN-based NG-RAN and a terrestrial NG-RAN is described.

[0268] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0269] FIG. 11A is a first example of multiple connections according to one embodiment of the disclosure of the present specification.

[0270] In the example of Figure 11a, different operators may manage two PLMNs for multi-connectivity (assuming there is a business agreement between the two operators).

[0271] The example in Fig. 11a is an example of multi-connectivity including different PLMNs of transparent NTN-based NG-RAN and cellular NG-RAN.

[0272] As illustrated in Figure 11a, the UE may be connected to access based on a transparent NTN-based NG-RAN (e.g., access via a satellite, NTN gateway, gNB, or 5G CN of a first operator). Additionally, the UE may be connected to access based on a terrestrial NG-RAN connected to a 5G CN of a second operator.

[0273] Alternatively, as in the example of Figure 11b, the two accesses for multi-connectivity may be managed by the same operator.

[0274] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0275] FIG. 11b is a second example of multiple connections according to one embodiment of the disclosure of the present specification.

[0276] In the example of Figure 11b, PLMNs may be managed by the same operator. Figure 11b illustrates multi-connectivity (same PLMN) including a transparent NTN-based NG-RAN and a cellular NG-RAN.

[0277] b) Multi-connectivity including two transparent NTN-based NG-RAN accesses.

[0278] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0279] FIG. 11c is a third example of multiple connections according to one embodiment of the disclosure of the present specification.

[0280] The example in Fig. 11c shows multi-connectivity between two transparent NTN-based NG-RANs.

[0281] For example, referring to Figure 11c, multi-connectivity may include a combination of two transparent NTN-based NG-RANs (e.g., GSO and NGSO-based). This may be useful for providing service to UEs in areas where services are not available. The example of Figure 11c may utilize a relatively low-latency NGSO-based NG-RAN to support delay-sensitive traffic, and a GSO-based NG-RAN that provides additional bandwidth to meet target throughput requirements.

[0282] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0283] FIG. 11d is a fourth example of multiple connections according to one embodiment of the disclosure of the present specification.

[0284] Figure 11d shows an example of multi-connectivity between two regenerative NTN-based NG-RANs (e.g., onboard gNBs).

[0285] An example according to Fig. 11d is an example of a case where two regenerative NTN-based NG-RANs (gNB on board) are combined with an inter-satellite link via two satellites of the same constellation.

[0286] Note that Figure 11d is for illustrative purposes only. Other architectures (e.g., a split NG-RAN architecture between satellite and terrestrial) may be considered. SRI represents the satellite radio interface in Figure 11d.

[0287] Examples of preconditions relevant to this use case include:

[0288] There may be some coverage overlap between the two NG-RAN access links involved.

[0289] If the PLMN of both access links is the same, the UE connects to the 5GC that provides both access links.

[0290] 5GC knows the characteristics of each of the two access links.

[0291] When different PLMNs are used for each access link, the UE gains access to other networks through roaming agreements. Information about each access link's characteristics can be exchanged between the two networks.

[0292] The UE is in connected mode on one or more of the access links.

[0293] Slices can be deployed and managed on both access links.

[0294] An example service flow related to this use case is as follows:

[0295] A UE may establish a VoIP, video, or data service over a single 3GPP access link, but its QoS (e.g., throughput, latency, etc.) may be inadequate. If another 3GPP access link becomes available, it will be activated and combined with the first link to support the required QoS for the service.

[0296] Depending on the target QoS of the service, the user plane traffic of the connection can be intelligently steered, split and switched bidirectionally between two 3GPP NG-RAN access links based on the specific performance of each access link, such as latency, throughput, jitter and error rate.

[0297] QoS requirements for user plane traffic can be determined through specific policies associated with different data flows or different traffic types within the same data flow.

[0298] Traffic is steered / segmented between access links based on QoS requirements (e.g., latency, throughput, jitter, error rate), traffic characteristics, wireless link conditions, and the UE's mobility speed. For example, traffic requiring low latency may be best steered / segmented to the access link with the lowest latency characteristics.

[0299] In the event of a handover, temporary radio link failure, or congestion on one access link, user plane traffic can be switched to the remaining active access link. Once the radio link is re-established, user plane traffic is split and steered across the two access links based on QoS.

[0300] Data volume and other traffic statistics reported on each access link are used for billing purposes.

[0301] According to the postcondition, due to appropriate steering, splitting and switching of user plane traffic, dual NG-RAN access connections with minimal NTNs can support targeted QoS that a single access cannot support.

[0302] Examples of existing features that partially or fully encompass the use case functionality include:

[0303] This use case can leverage and extend some of the existing service requirements, including:

[0304] - Multiple access technology (see TS 22.261 V19.3.0 S6.3)

[0305] - Multi-network connection and service provision between operators (refer to TS 22.261 V19.3.0 S6.18)

[0306] -NW slice (see S6.1 of TS 22.261 V19.3.0)

[0307] - Efficient user plane (see S6.5 of TS 22.261 V19.3.0)

[0308] Potential new requirements needed to support use cases include, for example:

[0309] Based on the use of at least one NR satellite RAT, the 5G system should be able to support simultaneous data transmissions by UEs associated with the same data session on two 3GPP 5G access networks, subject to operator policy. Based on the connection conditions (e.g., radio characteristics, mobility, congestion) of the two access networks and the UE's movement speed, the 5G system can optimally distribute user traffic between the two access networks.

[0310] When two 5G access networks are used simultaneously for the same data session, the 5G system can collect charging information for both links simultaneously.

[0311] Note that if the two 5G access networks belong to different PLMNs, single subscription and data anchoring on the HPLMN 5G CN is assumed.

[0312] Hereinafter, with reference to FIGS. 12 and 13, the use cases of the PLMN-to-PLMN scenario or the PLMN-SNPN scenario will be described.

[0313] This example scenario illustrates a stadium scenario where an ad-hoc / in-venue 5G NR deployment (high-capacity) is provided by one SNPN or PLMN network (MNO-A) and 5G NR coverage is provided by another PLMN outside the stadium (MNO-B). There is no network sharing between the two 5G networks. In this case, the MNO is the Mobile Network Operator.

[0314] The above example can be similarly applied to other local business locations such as campuses, companies, shopping malls, and factories.

[0315] MNO-B has a business and roaming partnership with MNO-A, which includes an agreement to lease additional capacity (from MNO-A) to provide ultra-broadband experiences to certain MNO-B special customers (e.g., "golden" customers). The agreement between MNO-A and B includes the ability for MNO-B users' data traffic to utilize additional NR connection links in PLMN-A, enabling them to connect at higher data rates (including anchoring and aggregation in the CN of the HPLMN). This capability is assumed to be supported by both PLMN CNs and the UEs (of the golden MNO-B users) and is associated with a set of traffic policies and conditions negotiated by the MNO. This capability is controlled by the HPLMN and can be provisioned (to UEs and CN entities).

[0316] Examples of preconditions relevant to this use case include:

[0317] Alice and Bob have arrived at a stadium to watch a concert by their favorite singer. Alice is a golden subscriber to MNO-B, and Bob is a "regular" MNO-B customer. Referring to the examples in Figures 12 and 13, Bob's UE, Bob UE, and Alice's UE, Alice UE, are depicted.

[0318] Both UEs are camped and registered with the MNO-B NW and are in the Idle state. Alice's UE supports dual (NR) radios.

[0319] Alice's specific traffic policy, part of the MNO-B "Golden User" contract, includes dual access usage for high-quality video calls, depending on QoS or traffic type. Otherwise, Alice's UE must use a single access / link from the MNO-B.

[0320] The service flow of FIG. 12 and FIG. 13 is as follows:

[0321] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0322] FIG. 12 is an example of a single 3GPP access connection according to one embodiment of the disclosure of the present specification.

[0323] Referring to Figure 12, Bob UE and Alice UE are illustrated. In Figure 12, both Bob UE and Alice UE are connected to a data network in PLMN-B based on 3GPP Access 1.

[0324] 1) Before the concert begins, Alice and Bob make a voice call to their best friend, describing the stadium atmosphere and promising to share a video of the concert later. Both are using a single 3GPP access connection (via PLMN-B).

[0325] Figure 12 is an example of an Alice & Bob data session using a single 3GPP access connection, according to step 1.

[0326] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0327] FIG. 13 is an example of a dual 3GPP access connection according to one embodiment of the disclosure of the present specification.

[0328] Referring to Figure 13, Alice UE uses both a connection based on 3GPP Access 1 and a connection based on 3GPP Access 2.

[0329] 2) When the concert begins, Alice and Bob decide to initiate a video call (with their friends) to share the live experience (with high-quality video settings). Alice's UE registers with NW-A and establishes a dual-access connection across the two networks. Bob's UE continues to use single-access through PLMN-B.

[0330] Figure 13 illustrates Alice's data session scenario using dual 3GPP access connections, according to step 2.

[0331] 3) Alice and Bob hang up the video call and continue enjoying the concert.

[0332] According to the use cases referenced in Figures 12 and 13, Alice's video quality was much better than Bob's video.

[0333] Describes an example of an existing feature that partially or fully encompasses the use case feature.

[0334] A) Steps 2 and 3 include a feature called Access Traffic Steering, Switching, and Splitting (ATSS). A similar feature described in this use case is supported by TS 25.301 V17.0.0 Section 5.3.2, but is limited to 3GPP access and non-3GPP dual access.

[0335] B) Existing service requirements (e.g., TS 22.261 V19.3.0 S6.18 and S6.41) capture some common multi-NW connectivity requirements and do not fully address or satisfy specific target use cases and capabilities. For example, in the prior art, for a user subscribed to a single operator, the use of multiple service networks operated by different operators is under the control of the home operator. For example, in the prior art, if multiple operators provide the same service, the UE should receive the subscribed service preferentially on the home operator's network, unless the home operator's network instructs otherwise. In this case, if the service is unavailable on the home operator's network (e.g., due to insufficient network coverage), the UE can receive the service on the network of another operator. In the prior art, the QoS provided on the partner operator's network for the same service may vary depending on the contract between the two operators and may differ from that provided on the domestic operator's network.

[0336] Examples of potential new requirements needed to support use cases include:

[0337] The 5G system shall be able to support mechanisms to coordinate, split and switch the user plane traffic of a UE for a single data session between two 5G networks belonging to two different PLMN operators (e.g., both using NR connectivity) or between an HPLMN and a SNPN.

[0338] It is assumed that an HPLMN subscription is used to access both networks, data traffic is anchored to HPLMN, and there are appropriate business agreements in place between the two network operators, including specific traffic routing policies based on geographic location, subscription, and traffic type.

[0339] Describes example use cases for UEs using terrestrial and satellite access.

[0340] Satellite access, known for its wide coverage, can improve service availability in areas with poor terrestrial access network coverage or poor radio conditions (e.g., multipath interference). When a fast-moving UE requests real-time services, such as IMS voice / video conferencing, it can simultaneously connect to the 5G system via terrestrial and satellite access, minimizing the impact of terrestrial network outages while providing continuous, stable service.

[0341] Eric is traveling to Saudi Arabia on business. He travels from Makkah to Madinah on the Haramain high-speed train, crossing 450 kilometers of desert at 300 kilometers per hour, to visit clients. He must handle urgent business via online video conferencing while on the road and resolve any issues before his arrival.

[0342] Examples of preconditions include:

[0343] TerrA's terrestrial access network offers good coverage in urban areas, suburban areas, and railway stops, but has limited coverage in rural areas and deserts between stops. SatA's satellite access network (e.g., LEO) provides nationwide coverage, and SatA can provide its own communications services. Note that TerrA is a terrestrial network operator, while SatA is a satellite network operator.

[0344] Based on this Agreement, TerrA may direct, divert or split User traffic onto the data path of the SatA network and consolidate it into TerrA's 5GC, taking into account SatA's service availability or coverage.

[0345] Eric's UE (e.g. mobile phone or wireless network card) is capable of dual 3GPP radio access, including satellite access, and is subscribed to a service-approved TerrA (PLMN NetA).

[0346] By default, only terrestrial access functions are activated.

[0347] An example of a service flow is as follows:

[0348] Eric activates the UE's satellite access feature while waiting to check in at the Macca train station.

[0349] UEs register with NetA based on their service preferences (e.g., instant chat when terrestrial access is preferred, HD TV when satellite access is preferred) over terrestrial access and satellite access networks.

[0350] After Eric connects, the online video conference begins via the terrestrial access network. During the one-hour conference, UE traffic is autonomously steered, switched, or split between the terrestrial and satellite network traffic paths with the help of TerrA's core network, and then converged on TerrA's core network to ensure uninterrupted video conference.

[0351] When the train reaches its destination, Eric disables satellite access and the UE updates its registration with NetA.

[0352] The postconditions associated with the example use case are as follows: For example, the video conference is completed smoothly and without interruption. The user is unaware of any navigation, transitions, or splits during the video conference.

[0353] Examples of existing features that partially or fully encompass the use case functionality are described below.

[0354] 5G systems must support UEs with multi-radio and single-radio capabilities.

[0355] 5G systems must support the ability to steer UEs to select specific 3GPP access networks based on operator policy.

[0356] Depending on operator policy, 5G systems must be able to provide simultaneous data transmission over different access technologies (e.g., NR, E-UTRA, non-3GPP) to access one or more 3GPP services.

[0357] A UE can use two or more access technologies simultaneously. In this case, the 5G system must be able to optimally distribute user traffic by selecting one of the access technologies in use, taking into account factors such as the service, traffic characteristics, radio characteristics, and the UE's movement speed.

[0358] 5G systems must be able to support data transmission optimized for different access technologies (e.g., 3GPP, non-3GPP) for UEs simultaneously accessing the network through different connections.

[0359] Service continuity between 5G terrestrial access networks and 5G satellite access networks owned by the same operator or by different operators under contract must be supported by the 5G system.

[0360] Examples of potential new requirements needed to support use cases include:

[0361] For example, a 5G system should support a mechanism to coordinate user traffic of a UE between different 3GPP access networks and the core network for a UE using dual 3GPP access, taking into account service preferences, traffic characteristics, radio characteristics, QoS, etc. For example, a 5G system should support seamless service continuity by switching and splitting user traffic paths between different 3GPP access networks and the core network for a UE using dual 3GPP access (e.g., NR and satellite access) based on network availability, service preferences, etc.

[0362] Looking at the above use cases, services can be provided to the UE through two 3GPP accesses (or 3GPP access links). For example, the UE may receive services from two 3GPP accesses connected to a single CN (Core Network) (or from two 3GPP accesses belonging to the same network). Alternatively, the UE may receive services from two 3GPP accesses connected to different CNs (or from two 3GPP accesses belonging to different networks). In the above, the network may be a PLMN or an NPN.

[0363] And, for some services, traffic may be steered, switched, and split through a PDU Session formed through two 3GPP accesses. Here, this PDU Session may be referred to as a Multi-Access (MA) PDU Session. In the prior art, an MA PDU Session was established through a 3GPP access and a non-3GPP access, but in the disclosure of this specification, a PDU Session may be established through two 3GPP accesses.

[0364] For some services, traffic may be transmitted through a PDU Session established via a single 3GPP access.

[0365] In the dual-steering example described above, it is assumed that the UE has a single subscription. Conventional technology has the problem of the UE registering with only one 5G CN for 3GPP access. Furthermore, conventional technology has not defined a method for providing services to the UE via two 3GPP accesses.

[0366] However, a UE may need to register with two 5G CNs to receive services over two 3GPP accesses. Furthermore, a UE may need to perform separate registration procedures for each 3GPP access, even for a single 5G CN, to receive services over two 3GPP accesses.

[0367] Additionally, if a UE is registered to two 5G CNs, the UE may need to select and / or decide on which 5G CN to establish a PDU Session for which service and to which 5G CN to transmit traffic.

[0368] To achieve this, UEs must simultaneously register using two 3GPP RATs on a single network (PLMN or SNPN). Alternatively, UEs must simultaneously register on different networks for each 3GPP RAT (both PLMNs, both SNPNs, or one PLMN and the other SNPN). Furthermore, the 3GPP RATs must be able to support various formats, such as NR+NR, NR+E-UTRA, TN-NTN, and NTN-NTN.

[0369] The DualSteer item defines the use cases and service requirements for providing services to UEs using two 3GPP accesses simultaneously in 5GS (TR 22.841 "Study on Upper layer traffic steer, switch, and split over dual 3GPP access"). Previously, a UE with a single subscription registered with only one 5G CN for 3GPP access. However, a UE may need to register with two 5G CNs to receive services through two 3GPP accesses. Furthermore, to receive services through two 3GPP accesses, a UE may need to register separately for each of the two 3GPP accesses within one 5G CN.

[0370] Meanwhile, 5GC manages terminal registration on a per-access basis. Therefore, if a terminal registers through one 3GPP access and then re-registers through a different 3GPP access, the registration initially performed through that 3GPP access cannot be maintained.

[0371] Therefore, a method to solve this problem is needed for one terminal to provide service through two 3GPP accesses.

[0372] Additionally, Dual Steer across two different PLMNs (e.g., HPLMN and VPLMN) needs to be supported. Scenarios where Dual Steer-related services can be provided to terminals even if the other VPLMN doesn't support Dual Steer need to be supported. If this is supported, the HPLMN network alone can be upgraded to provide services even if the VPLMN network doesn't support Dual Steer. This allows HPLMN operators to introduce Dual Steer services regardless of whether other operators' networks support Dual Steer.

[0373] Dual steer, where 5GS provides services to terminals using two 3GPP accesses simultaneously, is being discussed.

[0374] Meanwhile, 5GC manages terminal registration on a per-access basis. Therefore, if a terminal registers with one 3GPP access and then re-registers with a different 3GPP access, the UDM sends a message to the AMF deregistering the previous registration.

[0375] In other words, there is a problem in that the terminal cannot complete registration for two 3GPP accesses according to the prior art.

[0376] In the various examples disclosed in this specification, specific methods are needed to support UEs to receive dual steering services.

[0377] Various examples disclosed in this specification propose methods for supporting NSSRG when a UE performs dual 3GPP registration. Note that the methods disclosed in this specification can be applied in the same manner when a UE registers to different PLMNs for both 3GPP access and non-3GPP access.

[0378] According to various examples of the disclosure of this specification, a method for supporting registration in dual 3GPP access is comprised of a combination of one or more of the operations / configurations / steps described below.

[0379] In this specification, UE (User Equipment) and terminal may be used as terms with the same meaning.

[0380] In this specification, the terms “Subscriber” and “User” may be used interchangeably.

[0381] In this specification, Application Function (AF) and Application Server (AS) may be used as terms with the same meaning.

[0382] The methods presented below may be performed or used in combination or complementary manner.

[0383] In the explanation below, PLMN can be interpreted as SNPN, Equivalent PLMN, etc., and SNPN can be interpreted as PLMN.

[0384] 1. First example of disclosure of this specification

[0385] A first example of the disclosure of this specification includes an example of Dual 3GPP access Registration.

[0386] The examples described in this disclosure include operations based on the use of two 3GPP accesses, but these are merely examples. The scope of the disclosure in this disclosure is equally applicable to registration using two non-3GPP accesses.

[0387] According to the prior art, when a terminal registered in one network performs registration in another network, the new AMF performs Nudm_UECM_Registration with the UDM. Upon receiving Nudm_UECM_Registration, the UDM transmits Nudm_UECM_DeregistrationNotification to the old AMF.

[0388] An old AMF that receives Nudm_UECM_DeregistrationNotification can delete the terminal's context. Additionally, if the terminal has a PDU session, the old AMF requests the release of the PDU session.

[0389] Therefore, in order to support dual registration, these prior art operations must be prevented from being performed.

[0390] To address this issue, in the first example disclosed in this specification, the terminal may transmit a registration request message containing information indicating dual registration while performing registration. The information indicating dual registration may be, for example, a new registration type or a separate indication. Note that the information indicating dual registration may also be expressed as information related to dual registration.

[0391] However, the term "dual registration" is used here for illustrative purposes only. The scope of the disclosure of this specification is not limited by the term "dual registration." For example, other names (e.g., "additional registration," "second registration," "addition of the second 3GPP access," etc.) may be used in addition to the term "dual registration."

[0392] AMF can receive information that a terminal is performing dual registration. AMF can notify UDM that a terminal is performing dual registration by performing Nudm_UECM_Registration. For example, AMF can send UDM a Nudm_UECM_Registration message containing information related to dual registration.

[0393] Based on the fact that the terminal performs dual registration, the UDM may not send the Nudm_UECM_DeregistratioNotification to the old AMF. For example, based on receiving information that the terminal performs dual registration, the UDM may decide not to send the Nudm_UECM_DeregistratioNotification to the old AMF.

[0394] For example, when performing a registration procedure for a single network, a terminal may follow conventional behavior. That is, when transmitting a registration request message for the first network, information related to dual registration may not be included. When performing registration for dual registration for another network, the terminal may include information indicating that dual registration is being performed in the registration request message.

[0395] When a terminal performs a registration procedure due to mobility or a periodic registration procedure, the terminal transmits information that it is performing dual registration.

[0396] Information that a terminal has performed dual registration can be stored in the UDM via the AMF. The UDM can store and manage both the AMF / network where the terminal is registered without dual registration information and the AMF / network where the terminal is registered with dual registration information.

[0397] A terminal can also perform a registration procedure based on mobility. In this case, the modified AMF can perform Nudm_UECM_Registration with UDM. Based on information related to dual registration, UDM can determine which network to send Nudm_UECM_DeregistrationNotification to.

[0398] For example, in PLMN1, a terminal can perform registration according to the conventional procedure. In PLMN2, a terminal can transmit a registration request message including dual registration information and perform registration. In this case, since the Nudm_UECM_Registration message transmitted by the AMF of PLMN2 includes dual registration information, the UDM transmits Nudm_UECM_DeregistrationNotification to the old AMF stored with the dual registration information in PLMN2. For example, the terminal may have performed registration for AMF 1 of PLMN1 and then performed dual registration for AMF2 of PLMN2. If the serving AMF of PLMN2 changes from AMF2 to AMF3 due to terminal mobility, the new AMF, AMF3, performs Nudm_UECM_Registraiton to the UDM. Then, the UDM performs deregistration for AMF2 by transmitting a notification to the old AMF, AMF2. Additionally, UDM does not send Nudm_UECM_DeregistrationNotification to AMF of PLMN1 because deregistration should not be performed for AMF of PLMN1.

[0399] The terminal's access type may also be considered. Dual registration in 3GPP access does not affect registration in non-3GPP access.

[0400] AMF can request authentication from AUSF for terminal authentication. When performing an authentication request, AMF can notify AUSF that the terminal has requested dual registration.

[0401] After AUSF's terminal authentication is successful, AUSF can notify UDM of the terminal's authentication results. Based on the dual registration request information provided by AMF, AUSF can also notify UDM that the terminal has completed authentication during the dual registration process.

[0402] When AMF performs Nudm_UECM_Registration on UDM, UDM can decide whether to accept Nudm_UECM_Registration. For example, UDM can decide whether to accept AMF's request based on information transmitted by AUSF (e.g., information indicating that authentication was performed during dual registration).

[0403] AMF can send a Registration Accept message to the terminal containing information about whether dual registration was successful.

[0404] To support dual registration across two networks (HPLMN and VPLMN), a terminal can support dual registration through HPLMN alone, even if the VPLMN does not support dual registration. For example, a terminal may determine that the VPLMN does not support dual registration based on the following (e.g., one or more of the following combinations):

[0405] - If the terminal sends a registration request message containing information related to dual registration to the VPLMN, but the registration Accept message received by the terminal does not include whether dual registration was successful; and / or

[0406] - If the 5GS network feature support included in the Registration Accept message received by the terminal includes information that dual registration support is not supported or does not include information related to dual registration support.

[0407] If at least one of the two cases above applies, the terminal can perform a registration procedure for dual registration with another network (e.g., HPLMN). After the AMF receives the registration request message, it can notify the UDM that the terminal is performing dual registration by performing Nudm_UECM_Registration.

[0408] Then, the UDM can recognize that the terminal has performed dual registration. The UDM may receive a Nudm_UECM_Registration request for the same terminal from an AMF in another network (e.g., VPLMN). In this case, the UDM may not send a Nudm_UECM_DeregistrationNotification to the network with which dual registration has been performed (e.g., HPLMN).

[0409] Based on this behavior, dual registration of the UE can be supported even if the VPLMN does not support dual registration.

[0410] In the example described above, the UE performed the registration procedure with the VPLMN and then with the HPLMN. However, the reverse situation may also occur, or two registration procedures may be performed with the VPLMN. For example, after registering with the visited network, the UE may perform another registration based on 3GPP access with the visited network.

[0411] After performing dual registration with the HPLMN, a UE may then register with a VPLMN that does not support dual registration. In this case, if the UE is permitted / authorized to perform dual registration, the UDM may delay sending the Nudm_UECM_DeregistrationNotification message to the old AMF in the HPLMN based on a timer. This action may also be performed based on the UDM's local policy / configuration.

[0412] Before the above timer expires, if the UE performs a registration procedure for dual registration with another network (e.g., HPLMN), the UDM may stop the timer. If the registration procedure for dual registration with another network (e.g., HPLMN) is not performed by the timer expires, the UDM may send a Nudm_UECM_DeregistrationNotification to the old AMF of the HPLMN.

[0413] The old AMF of the HPLMN can receive Namf_Communication_RegistrationStatusUpdate from the AMF of another PLMN. If the old AMF of the HPLMN is also allowed / authorized for the UE to perform dual registration, the old AMF of the HPLMN may not perform the task of clearing the UE's PDU Session for a certain period of time based on a timer. This action may be performed based on the AMF's local policy / configuration. After the UE performs the registration procedure for dual registration, the old AMF of the HPLMN stops the timer and maintains the UE's context, thereby preventing the UE's service from being interrupted.

[0414] Hereinafter, with reference to FIGS. 14a, 14b and 15, the first and second examples of the procedure according to the first example of the disclosure of the present specification will be described.

[0415] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0416] Figures 14a and 14b are a first example of a procedure according to the first example of the disclosure of the present specification.

[0417] A first example according to the examples of FIGS. 14a and 14b describes operations based on different networks (e.g., PLMN + PLMN, PLMN + SNPN, SNPN + SNPN).

[0418] In the examples of FIGS. 14a and 14b, descriptions of operations identical to those in the prior art are omitted, and descriptions are focused on matters proposed in this specification.

[0419] Referring to FIGS. 14a and 14b, an example is shown where a UE performs dual registration through another network.

[0420] 1. The terminal can perform the registration procedure in PLMN1.

[0421] For example, a UE can initiate a registration procedure by sending a registration request message to the AMF. The UE can send a Registration Request message that includes UE MM Core Network Capability. The UE can inform the AMF whether the UE supports dual registration through the UE MM Core Network Capability. Upon receiving this information, the AMF can send the UE a registration acceptance message that includes 5GS network feature support related to dual registration. By sending the 5GS network feature support, the AMF can inform the UE whether the network supports dual registration.

[0422] At this time, based on the subscriber information obtained from the UDM and the operator policy set in the AMF, the AMF may inform the terminal whether it supports 5GS network feature support related to dual registration only when dual registration can be allowed to the terminal.

[0423] Alternatively, 5GS network feature support may only include the capability to indicate whether the network supports dual registration. In addition to 5GS network feature support, AMF may also indicate whether dual registration is allowed for the terminal through a separate indication.

[0424] 2. The terminal can send a registration request message to PLMN2. The registration request message may be a registration request message for initial registration.

[0425] For example, a terminal performs registration in PLMN2. At this time, the terminal may transmit a registration request message that includes an indication of dual registration or a new registration type indicating dual registration.

[0426] In this process, an operation to exchange capabilities between the terminal and the network can be performed, similar to step 1.

[0427] 3. The AMF of PLMN2 can perform authentication for the terminal. While requesting authentication from the AUSF, the AMF can also inform the AUSF that the terminal has requested dual registration.

[0428] For example, AMF may send an authentication request message to AUSF containing information related to dual registration.

[0429] 4-9. EAP authentication can be performed according to the conventional procedure. For reference, steps 3 to 7 are examples of the authentication process for the terminal. Steps 8 to 9 are examples of the process in which the AMF notifies the AUSF that authentication for the terminal has been successful. For example, the AUSF can send a request message related to authentication to the UDM and receive a response message from the UDM. The AUSF can send an authentication response message to the AMF. The AMF can exchange authentication request / response messages related to EAP authentication with the UE. The AMF can send an authentication request message related to dual registration to the AUSF and receive a response message from the AUSF.

[0430] 10-11. The AUSF can notify the UDM that the terminal has successfully authenticated. For example, the AUSF can send a request message to the UDM containing information about the authentication result. This request message can include information indicating that the terminal has requested dual registration. Furthermore, this request message can include information indicating that the terminal has successfully authenticated, information related to the time of successful authentication, the serving network name, and information indicating that dual registration has been requested. The AUSF can notify the UDM that the terminal has requested dual registration. The UDM can then send a response message to the AUSF.

[0431] 12. AMF can signal successful authentication by sending a Security Mode Command to the terminal. The terminal responds to the Security Mode Command by sending a Security Mode Complete message to AMF.

[0432] 13. AMF sends Nudm_UECM_Registration to UDM. At this time, AMF can also notify that the terminal has requested dual registration. For example, AMF can send a message containing information related to dual registration to UDM.

[0433] The UDM can determine whether to allow dual registration for a terminal. For example, the UDM can consider the information transmitted by the AUSF in step 10 (information indicating successful terminal authentication, the time of success, the serving network name, and information indicating that dual registration was requested).

[0434] For example, if information is received from the AUSF that the terminal has successfully authenticated without requesting dual registration, the UDM may send an error to the AMF in response to the request.

[0435] If the UDM does not allow dual registration for the terminal, the UDM can perform the following actions. For example, i) the UDM can return an error in response to the Nudm_UECM_Registration from the AMF and additionally send a reason for the error. For example, ii) the UDM can process the Nudm_UECM_Registration normally and send a Nudm_UECM_DeregistrationNotification to the AMF of the PLMN1 where the UDM is already registered. The UDM can inform the AMF whether or not it allows dual registration for the terminal.

[0436] 14-15. AMF can retrieve subscriber information for a terminal from the UDM by performing Nudm_SDM_Get. To receive updates to the terminal's subscriber information (i.e., to receive information on changes to subscriber information), AMF can perform Nudm_SDM_Subscribe. If the terminal's subscriber information includes information on whether dual registration is permitted, AMF can determine whether to allow registration of the terminal based on this information.

[0437] 16. AMF performs the AM Policy Association Establishment process for terminals.

[0438] 17. AMF can send a Registration Accept message containing dual registration-related information to the terminal. AMF can notify the terminal that the registration has been successfully completed.

[0439] 18. AMF can perform the UE Policy Association Establishment process for terminals.

[0440] 19. The UE may send a Registration Complete message if necessary.

[0441] Hereinafter, a second example of the disclosure of the present specification is described with reference to FIG. 15.

[0442] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0443] Figure 15 is a second example of a procedure according to the first example of the disclosure of this specification.

[0444] A second example according to the example of Fig. 15 describes an operation based on the same network.

[0445] In the example of Fig. 15, the description of the same operation as the prior art is omitted, and the description is centered on the matters proposed in this specification.

[0446] 1. The terminal can perform the registration procedure in the PLMN.

[0447] For example, a UE can initiate a registration procedure by sending a registration request message to the AMF. The UE can send a Registration Request message that includes UE MM Core Network Capability. The UE can inform the AMF whether the UE supports dual registration through the UE MM Core Network Capability. Upon receiving this information, the AMF can send the UE a registration acceptance message that includes 5GS network feature support related to dual registration. By sending the 5GS network feature support, the AMF can inform the UE whether the network supports dual registration.

[0448] At this time, based on the subscriber information obtained from the UDM and the operator policy set in the AMF, the AMF may inform the terminal whether it supports 5GS network feature support related to dual registration only when dual registration can be allowed to the terminal.

[0449] Alternatively, 5GS network feature support may only include the capability to indicate whether the network supports dual registration. In addition to 5GS network feature support, AMF may also indicate whether dual registration is allowed for the terminal through a separate indication.

[0450] 2. The terminal performs registration in the PLMN where registration was performed in step 1. For example, the terminal may transmit a registration request message. The registration request message may be a registration request message for initial registration.

[0451] At this time, the terminal can transmit a registration request message containing an indication indicating dual registration or a new registration type indicating dual registration. During this process, capabilities can be exchanged between the terminal and the network, similar to step 1.

[0452] The terminal can send a registration request message by including the 5G-GUTI allocated in step 1 in the Registration Request message.

[0453] The NG-RAN performs AMF selection based on the S-TMSI included in the AS signaling / RRC message by the UE. If there is an interface between AMF1 and the NG-RAN, the same AMF may be selected. Even if the same AMF is selected, different AMFs may be selected due to cell selection / reselection, handover, and other operations in each access network. To handle such cases, the AMF can create and manage separate contexts for each registration.

[0454] 3-4. AMF2 can retrieve the UE's context from the UE's current serving AMF (i.e., AMF1) based on the 5G-GUTI transmitted by the UE. For example, AMF2 can transmit a message containing information indicating that the UE is performing dual registration to AMF1. Upon receiving this message, AMF1 can recognize that the UE is performing dual registration. Based on recognizing dual registration, AMF1 may not start a timer to clear the UE's context. This process may be omitted if there is no interface between AMF2 and AMF1, or if the operator configures it not to retrieve the UE context during dual registration.

[0455] 5. AMF2 can perform the terminal authentication process. Based on the UE context obtained from AMF1, AMF2 can also reuse the security context in the UE context without authentication. Regardless of whether the security context is reused, the terminal can separately manage the security contexts used in the first and second registrations, as described in step 2.

[0456] 6. AMF2 sends Nudm_UECM_Registration to UDM. At this time, AMF2 can also notify that the terminal has requested dual registration. Based on this, UDM can decide not to send Nudm_UECM_DeregistrationNotification to AMF1.

[0457] 7-8. AMF can retrieve subscriber information for a terminal from the UDM by performing Nudm_SDM_Get. To receive updates to the terminal's subscriber information (i.e., to receive information on changes to subscriber information), AMF can perform Nudm_SDM_Subscribe. If the terminal's subscriber information includes information on whether dual registration is permitted, AMF can determine whether to allow registration of the terminal based on the subscriber information.

[0458] 9. AMF2 performs the AM Policy Association Establishment process for the terminal. If information regarding the AM Policy Association is received from AMF1, AMF1 selects the same PCF based on this information.

[0459] For reference, this process was previously performed optionally based on AMF2's decision. However, according to the first example disclosed in this specification, when performing dual registration, AMF2 must select the same AM PCF. By selecting the same AM PCF, AMF2 can transmit different RFSP indices to each AMF. Consequently, the same RAT may not be selected for each 3GPP access.

[0460] 10. AMF2 can send a Registration Accept message containing dual registration-related information to the terminal. AMF can notify the terminal that the registration has been successfully completed.

[0461] 11. AMF2 performs the UE Policy Association Establishment process for the terminal. If information regarding the UE Policy Association is received from AMF1, AMF2 selects the same PCF based on this information. While this process is currently optional and determined by AMF2, dual registration can ensure the selection of the same UE PCF.

[0462] 12. The UE sends a Registration Complete message if necessary.

[0463] 2. Second example of disclosure of this specification

[0464] A second example of the disclosure of this specification includes an example in which an AMF manages a UE contest.

[0465] AMF can manage UE context for each 3GPP access registration. To achieve this, AMF can store and manage UE context for each 3GPP access. For example, AMF can store and manage 5G-GUTI, RAN UE NGAP ID, AMF NGAP ID, etc. for each 3GPP access.

[0466] The terminal can perform mobility registration for each 3GPP access according to the conventional operation. At this time, the terminal may leave the registration area received from the network during the first registration procedure. In this case, the terminal may not transmit information indicating dual registration to the network while performing mobility registration. In the second registration procedure, the terminal may leave the registration area received from the network. In this case, the terminal transmits a Registration Request message containing information indicating dual registration while performing mobility registration. In addition, the terminal must transmit the 5G-GUTI allocated for each 3GPP access when performing mobility registration.

[0467] When the UE performs this action, the new AMF can perform the following actions. For example, the new AMF can request the old AMF to transmit the UE context. In this case, if the new AMF receives dual registration information, the AMF can transmit a request message containing the dual registration information (or the 5G-GUTI allocated by the corresponding access network) to the old AMF. This allows the old AMF to determine whether to transmit the UE context for the first registration or the UE context for the second registration when transmitting the UE context to the new AMF. For example, if the new AMF transmits dual registration information (or the 5G-GUTI allocated by the corresponding access network) to the old AMF, the old AMF forwards the UE context of the registered UE to the new AMF based on the registration request message containing the dual registration indication. Conversely, if the new AMF does not transmit dual registration information, the old AMF forwards the UE context of the registered UE to the old AMF based on the registration request message that does not contain the dual registration indication.

[0468] Additionally, if dual registration information is present, the new AMF can send Nudm_UECM_Registration containing the dual registration information to the UDM. Based on this, the UDM can decide to which AMF to send Nudm_UECM_DeregistrationNotification.

[0469] For example, if AMF performs Nudm_UECM_Registration without including dual registration information, UDM sends Nudm_UECM_DeregistrationNotification to the old AMF that performed Nudm_UECM_Registration without dual registration information. And, if AMF performs Nudm_UECM_Registration with dual registration information, UDM sends Nudm_UECM_DeregistrationNotification to the old AMF that performed Nudm_UECM_Registration with dual registration information.

[0470] Alternatively, the terminal or AMF can assign an ID that distinguishes each 3GPP access. Based on the assigned ID, the terminal or AMF can indicate which context the request / update is for.

[0471] 3. Third example of disclosure of this specification

[0472] A third example of the disclosure of this specification includes an example of using different NG-RAN resources when a terminal performs dual registration.

[0473] When transmitting data using two 3GPP accesses, the network may not want the terminals to use the same NG-RAN resources. For example, the network may want to improve reliability by performing duplication using dual 3GPP accesses. In this case, using the same NG-RAN resources creates dependencies on each 3GPP path, making it difficult to effectively improve reliability. Furthermore, the network may have priorities or preferences for each 3GPP access and may only want to use the other 3GPP access if the service is unavailable through that 3GPP access. In such cases, it is necessary to prevent the two 3GPP accesses from using the same NG-RAN resources. The following methods can be used to achieve this.

[0474] [3-1] Example based on RFSP Index

[0475] A terminal can be configured to select the same Access and Mobility Policy Control Function (AM-PCF) when performing registration using two 3GPP accesses. In this case, the AM-PCF can transmit a different Radio Frequency Selection Priority (RFSP) Index to the terminal for each registration. To achieve this, PCF information can be stored in the subscriber information of the UDM. Alternatively, the AM-PCF selected by the AMF in the first registration can be stored in the UDM.

[0476] In the case of roaming, there is no interface between the V-AM-PCF and the H-AM-PCF, and this interface may need to be supported. To this end, when the terminal registers with the AMF in the visited network, the terminal can send a registration request message containing information related to dual registration to the AMF. This information is passed on to the V-AM-PCF, and the V-AM-PCF, recognizing dual registration, can create an association with the H-AM-PCF. At this time, the AMF can pass on the H-AM-PCF information to the V-AM-PCF. If the V-AM-PCF has H-AM-PCF information, it can create an association between the V-AM-PCF and the H-AM-PCF regardless of the dual registration information. In addition, a Proxy-PCF or Intermediate-PCF can be deployed at the network border to connect the AM-PCF of its own network to the AM-PCF of another network. AM-PCFs belonging to different networks can also communicate through the Proxy-PCF or Intermediate-PCF. For example, a path of the form H-AM-PCF <-> H-Proxy-PCF <-> V-Proxy-PCF <-> V-AM-PCF can be used.

[0477] Additionally, the AM-PCF can consider the currently used service when determining the RFSP Index. This can be achieved by using the procedure in TS 23.502 V18.2.0 clause 4.16.14.2. Based on this, the AM-PCF can determine the RFSP Index according to the currently used service of the UE. In addition, by updating the existing procedure, the SM PCF can transmit information related to the steering policy used in the PDU Session created using dual 3GPP access (e.g., steering mode information) to the AM PCF. The AM PCF can refer to this information to determine the RFSP Index.

[0478] [3-2] Example based on UDM subscription

[0479] When AMF performs Nudm_UECM_Registration, UDM can transmit information such as RFSP Index, Service Area Restriction, and RAT restriction to AMF. In this case, UDM can set different RFSP Index, Service Area Restriction, and RAT restriction information and transmit them to AMF. Based on this, each 3GPP access uses different region / RAT / NG-RAN resources. For this purpose, UDM can remember the subscription information transmitted to each AMF. Based on this, when the terminal no longer uses dual registration, UDM can send updated subscription information.

[0480] 4. Fourth example of disclosure of this specification

[0481] A fourth example of the disclosure of this specification includes an example supporting non-3GPP access.

[0482] A terminal can perform additional registration for non-3GPP access while dual-registered for 3GPP access. Since the terminal is dual-registered for 3GPP access, it has two 5G-GUTIs used by 3GPP.

[0483] According to prior art, when registering with non-3GPP access, a terminal must include the 5G-GUTI assigned to 3GPP access in the registration request message. If a terminal is registered for dual 3GPP access on the same network, the terminal has difficulty determining which 5G-GUTI to include.

[0484] To inform the UE which 5G-GUTI information to use, the AMF can perform the following actions. For example, the AMF can allocate 5G-GUTI to a UE supporting dual registration in 3GPP access. In this case, the AMF can send the Registration Accept message including the primary 5G-GUTI information to the UE. For example, the AMF can include the 5G-GUTI in the Registration Accept message and inform the UE whether it is the primary 5G-GUTI / secondary 5G-GUTI based on a separate IE (or, the AMF can only inform the UE of the primary 5G-GUTI).

[0485] Based on the information related to 5G-GUTI, the terminal transmits a Registration Request including the 5G-GUTI set as primary in non-3GPP access.

[0486] The AMFs may be different. For example, the AMFs responsible for each 3GPP access may be different. In this case, since the different AMFs independently allocate GUTIs, a problem may arise where both AMFs allocate the primary GUTI. To address this, a method for allocating the primary 5G-GUTI / secondary 5G-GUTI when the AMFs are different is needed. For example, the AMF may request the UDM to store the allocated 5G-GUTI information and / or information indicating that the primary 5G-GUTI has been allocated. The stored information can then be forwarded by the UDM to the other AMF in the form of subscription data.

[0487] For example, AMF may notify the terminal of the secondary 5G-GUTI when the second registration procedure is performed based on the subscription information.

[0488] As another example, if a terminal transmits a registration request message containing dual registration information, the 5G-GUTI received by the terminal during the registration procedure may be considered a secondary 5G-GUTI. In other words, the 5G-GUTI allocated while performing registration without dual registration information may be set as the primary 5G-GUTI.

[0489] As another example, the terminal may consider the 5G-GUTI received in the first registration procedure or a preceding registration procedure as the primary 5G-GUTI.

[0490] As another example, the terminal may consider the most recently received 5G-GUTI as the primary 5G-GUTI.

[0491] Based on the various examples described above, when a terminal performs registration via non-3GPP access, the terminal can use the security context associated with the selected 5G-GUTI.

[0492] The operation according to the fourth example of the disclosure of this specification may be applied only when the terminal uses the same PLMN in 3GPP access and non-3GPP access.

[0493] In 3GPP access, a terminal may register through different networks. In this case, when registering in non-3GPP access, the terminal can select a 5G GUTI assigned to the same PLMN as the network it is registering in, regardless of the primary 5G GUTI.

[0494] 5. Fifth example of disclosure of this specification

[0495] A fifth example of the disclosure of this specification includes an example of using different AMFs in each 3GPP access when supporting dual registration in the same network.

[0496] The fifth example of the disclosure in this specification assumes that it is used when a terminal performs dual 3GPP registration in the same network or an equivalent network. However, the scope of the disclosure in this specification is not limited thereto. For example, the fifth example of the disclosure in this specification may also be applied when dual 3GPP registration is performed through different networks.

[0497] [5-1] Operation based on core network

[0498] This method ensures that when a terminal performs dual registration on the same network, it always uses a different serving AMF. Specifically, a terminal can perform registration on one 3GPP access and then on another 3GPP access. In this case, if the RAN selects the same AMF to perform registration, the AMF can redirect the corresponding Registration Request message to the other AMF. Based on this redirection, the terminal can always be registered with two different AMFs.

[0499] If different AMFs serve a terminal due to terminal mobility, then a single AMF may serve the terminal again (e.g., when AMF reselection occurs due to a handover process or idle mode mobility of the terminal). In this case, the AMF may relocate the serving AMF of one 3GPP access. In addition, when the terminal performs mobility registration, the terminal may transmit a registration request message including GUTI information allocated by the AMF of each 3GPP access. Currently, the terminal can perform only one registration at a time, but this restriction can be lifted in the case of dual registration. That is, in the case of mobility registration, the terminal can perform registration in parallel.

[0500] Referring to the example of FIG. 16, a first example of a procedure according to the fifth example of the disclosure of the present specification based on [5-1] is described.

[0501] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0502] Figure 16 is a first example of a procedure according to the fifth example of the disclosure of this specification.

[0503] Referring to Figure 16, an example of AMF performing redirection when dual registration is performed within the same network is described.

[0504] Referring to Fig. 16, an example is described in which a different AMF is always selected based on AMF redirection when a terminal performs dual registration through the same network.

[0505] 1. It can be performed in the same manner as step 1 of Fig. 15.

[0506] 2. The terminal performs registration in the PLMN where registration was performed in step 1. For example, the terminal may transmit a registration request message. The registration request message may be a registration request message for initial registration.

[0507] At this time, the terminal can transmit a registration request message containing an indication indicating dual registration or a new registration type indicating dual registration. During this process, capabilities can be exchanged between the terminal and the network, similar to step 1.

[0508] The terminal can send a registration request message by including the 5G-GUTI allocated in step 1 in the Registration Request message.

[0509] The NG-RAN performs AMF selection based on the S-TMSI included in the AS signaling / RRC message by the terminal. If there is an interface between the NG-RAN and AMF1, the same AMF can be selected.

[0510] At this time, the terminal can transmit the AS signaling / RRC message without including GUAMI and S-TMSI in the AS signaling / RRC message so that an AMF different from AMF1 is selected.

[0511] Based on the UE Context, 5G-GUTI, and dual registration information stored in AMF#1, AMF#1 can recognize that this is the second registration for the same terminal. AMF#1 can then decide to redirect to another AMF.

[0512] Based on whether an interface exists between AMF#1 and Target AMF, step 3 or steps 4a and 4b may be performed.

[0513] 3. If AMF#1 decides to redirect to another AMF, AMF#1 selects the target AMF (AMF#2 in this example). At this time, AMF selection can be performed based on terminal capability, AMF capability, slice information, and information that dual registration is performed. If there is an interface between the target AMF and AMF#1, AMF#1 can use Namf_CommunicationN1MessageNotify to forward the terminal's Registration Request message to the target AMF. During this process, AMF#1 can send information to AMF#2 notifying that the terminal is performing dual registration.

[0514] If there is no interface between AMF#1 and Target AMF, AMF#1 can perform redirection via NG-RAN, in which case steps 4a and 4b are performed.

[0515] 4a. AMF#1 sends a Reroute NAS Request message to the target AMF. To inform the target AMF, AMF#1 can include the AMF Pointer as well as the AMF Set ID in this message.

[0516] For example, AMF can select a target AMF through NRF or based on local configuration. To support target AMF selection through NRF, AMF#1 can notify NRF whether it supports dual registration when performing Register. Also, AMF can notify NRF that it is performing AMF discovery for dual registration when performing discovery. In this case, NRF can select a target AMF instance and notify AMF#1 of the selected target AMF instance. In other words, it can notify AMF#1 of the AMF Pointer. In addition, AMF#1 can add information indicating that the terminal performs dual registration to the Source to Target AMF Information Reroute IE and notify the target AMF through a Reroute NAS Request message.

[0517] 4b. NG-RAN transmits a message to the target AMF based on the target AMF information transmitted by AMF#1.

[0518] 5. AMF#2 performs the remaining registration procedures.

[0519] [5-2] RAN-based operation

[0520] When a terminal performs registration, the terminal may add information to the AS signaling / RRC message indicating that it is performing dual registration with GUAMI and S-TMSI. Alternatively, instead of the information indicating that it is performing dual registration, information indicating that it is performing AMF selection other than the terminal's serving AMF (the AMF identified by GUAMI and S-TMSI) may be included.

[0521] The NG-RAN, upon receiving this information from the terminal, can perform AMF selection. The NG-RAN may select an AMF other than the one identified based on the GUAMI and S-TMSI transmitted by the terminal. Based on the NG-RAN's selection, the AMF selected in the first registration may differ from the AMF selected in the second registration.

[0522] As another example, when performing a second registration, the UE may transmit a Registration Request without including the GUAMI and S-TMSI information received in the first registration in the AS signaling / RRC message. In this case, since there is no information about the AMF selected in the first registration, a new AMF or the same AMF may be selected in the second registration. If the same AMF is selected, redirection to a different AMF may be performed based on the operation according to the example in [5-1].

[0523] Referring to the example of FIG. 17, a second example of the procedure according to the fifth example of the disclosure of the present specification based on [5-2] is described.

[0524] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0525] Figure 17 is a second example of a procedure according to the fifth example of the disclosure of this specification.

[0526] The example in Figure 17 illustrates an example of NR-RAN selecting an AMF when dual registration is performed in the same network. NG-RAN may select a different AMF.

[0527] 1. It can be performed in the same manner as step 1 of Fig. 15.

[0528] 2. The terminal performs registration in the PLMN where registration was performed in step 1. For example, the terminal may transmit a registration request message. The registration request message may be a registration request message for initial registration.

[0529] At this time, the terminal can transmit a registration request message containing an indication indicating dual registration or a new registration type indicating dual registration. During this process, capabilities can be exchanged between the terminal and the network, similar to step 1.

[0530] At this time, the terminal can send a registration request message by including the 5G-GUTI allocated in step 1 in the Registration Request message. The terminal can include information indicating that dual registration is performed in the AS signaling / RRC message and send the AS signaling / RRC message together with 5G-GUTI and S-TMSI. The NG-RAN that receives this selects an AMF (e.g., AMF#2) different from the AMF (e.g., AMF#1) selected by GUAMI and S-TMSI.

[0531] 3. The NG-RAN transmits a Registration Request message to the selected AMF. During this process, information indicating that the terminal is performing dual registration (transmitted via AS signaling / RRC message) can also be transmitted to the AMF.

[0532] 4. AMF#2 performs the remaining registration procedures.

[0533] 6. Sixth example of disclosure of this specification

[0534] According to the sixth example of the disclosure of this specification, when dual registration is supported in the same network, the same AMF can always be used in each 3GPP access.

[0535] For example, when performing dual registration on the same network, the same serving AMF can always be used.

[0536] To this end, when a terminal performs registration using another 3GPP access after performing registration in one 3GPP access, the terminal can include the 5G-GUTI allocated by the other 3GPP access in the Registration Request message. By including the 5G-GUTI allocated by the other 3GPP access, the network can use the same AMF.

[0537] Additionally, the terminal can enable the base station to select the same AMF by including GUAMI or S-TMSI in the AS signaling / RRC message. If the same AMF cannot be used due to the absence of an N2 connection, one AMF can act as a relay node to transmit signaling from another AMF.

[0538] For reference, the first to sixth examples of the disclosure of the present specification described above may be applied independently, or one or more examples may be applied in combination.

[0539] Hereinafter, with reference to FIG. 18, an example of operations according to an embodiment of the disclosure of the present specification is described. The example of FIG. 18 may include operations based on an example including at least one of Examples 1 to 6 of the disclosure of the present specification.

[0540] The following drawings are intended to illustrate specific examples of the present specification. The names of specific devices and the names of specific signals, messages, and fields depicted in the drawings are provided for illustrative purposes only, and the technical features of this specification are not limited to the specific names used in the drawings.

[0541] FIG. 18 illustrates an example of operations according to one embodiment of the disclosure of the present specification.

[0542] For reference, the procedure illustrated in FIG. 18 is merely an example, and the scope of the disclosure of this specification is not limited by the example in FIG. 18.

[0543] For example, with respect to the example of FIG. 18, the operations described in the examples of FIGS. 1 to 17 may also be applied. For example, even if operations, contents, etc. are not directly described in the example of FIG. 18, operations, contents, etc. described in various examples of the disclosure of this specification may be applied.

[0544] The operations illustrated in FIG. 18 are merely examples, and the scope of the disclosure of this specification is not limited to the operations illustrated in FIG. 18.

[0545] In step (S1801), the UE may transmit a registration request message to the AMF.

[0546] The registration request message may contain information related to dual registration.

[0547] For example, the UE may receive capability information from one or more AMFs, including the AMF. Based on the capability information received from the one or more AMFs, the UE may determine to which AMF to send a registration request message containing information related to dual registration.

[0548] For example, the AMF may send an authentication request message to the AUSF requesting authentication for the UE. The authentication request message may include information related to dual registration. The AMF may receive an authentication response message from the AUSF.

[0549] For example, if AUSF's authentication for the UE is successful, based on information related to dual registration, AUSF may transmit information to UDM that the UE has requested dual registration.

[0550] For example, when the AMF receives an authentication response message, the AMF may send a security mode command message to the UE. The AMF may receive a security mode complete message from the UE.

[0551] For example, the registration request message may be a message based on mobility registration. In this case, the AMF may send a request message requesting a UE context to the other AMF. This request message may include information related to dual registration.

[0552] In step (S1802), the AMF may transmit a request message to the UDM. For example, the request message may be a registration message related to the UDM.

[0553] The request message (or registration message) may contain information related to dual registration.

[0554] For example, before performing step (S1802), the UDM may receive a first request message (or first registration message) from another AMF, the first AMF. The AMF in step (S1802) may also be referred to as the second AMF, and the request message (or registration message) may also be referred to as the second registration message.

[0555] For example, information related to dual registration may prevent the UDM from sending a deregistration message to another AMF associated with the UE (e.g., the first AMF) if the UDM allows dual registration.

[0556] For example, UDM can decide whether to allow dual registration.

[0557] For example, before performing step (S1802), the UDM may receive a request message from the AUSF, which includes information related to authentication for the UE, a serving network name, and information related to the dual registration. Based on the request message received from the AUSF and the registration message received from the AMF, the UDM may determine whether to allow dual registration for the UE.

[0558] In step (S1803), the UDM may transmit a response message to the AMF. For example, the response message may be a response message to a registration message related to the UDM.

[0559] The response message may include information about whether dual registration is allowed.

[0560] For example, if UDM does not allow the above double registration, the response message may include error information.

[0561] For example, the AMF may determine whether to allow dual registration based on information about whether dual registration is allowed and subscriber information about the UE obtained from the UDM. For example, even if the UDM allows dual registration, the AMF may not allow dual registration.

[0562] For example, if the UDM does not allow the above dual registration, the UDM may send a deregistration message to the other AMF.

[0563] In step (S1804), the AMF may transmit a registration response message to the UE. The registration response message may be, for example, a registration acceptance message.

[0564] For example, the registration response message may include information regarding the success or failure of dual registration. For example, the registration response message may include information indicating that dual registration was successful.

[0565] For example, the AMF may transmit information to the UE regarding whether the AMF supports dual registration. For example, information regarding whether the AMF supports dual registration may be included in the registration response message.

[0566] For example, the registration response message may include information indicating the primary 5G-GUTI among the multiple 5G-GUTIs allocated to the UE. For example, after completing dual registration, the UE may perform a registration procedure via a non-3GPP access. In this case, the UE may transmit a registration request message including the primary 5G-GUTI to the non-3GPP access.

[0567] For example, the AMF may be the AMF of the VPLMN. In this case, the UE can determine whether the VPLMN supports dual registration. For example, the registration response message may not include information regarding the success or failure of the dual registration, or may include information indicating that dual registration is not supported. In this case, the UE can determine that the VPLMN does not support dual registration. If the VPLMN does not support dual registration, the UE can send a registration request message containing information related to dual registration to the AMF of the HPLMN.

[0568] According to one embodiment of the disclosure of the present specification, when a terminal performs dual registration, the following actions may be performed to prevent Nudm_UECM_DeregistrationNotification from being transmitted to an AMF managing other 3GPP access. For example, the terminal may notify the AMF that it performs dual registration, and the AMF may notify the UDM that it is dual registration.

[0569] According to one embodiment of the disclosure of this specification, a terminal can consider the dual registration capability of each network. Accordingly, the terminal can determine which network to transmit information indicating that it is performing dual registration.

[0570] According to one embodiment of the disclosure of the present specification, a terminal may perform mobility registration on each 3GPP access while performing dual registration. In this case, UE context transmission may be performed between AMFs. In this case, in order to transmit only the UE context for a specific 3GPP access of the terminal, when the AMF requests the UE context, information indicating dual registration may be transmitted, or a 5G-GUTI allocated to the terminal through a specific 3GPP access may be transmitted.

[0571] According to one embodiment of the disclosure of this specification, a terminal may perform registration via non-3GPP access. In this case, the terminal may select a 5G-GUTI allocated without dual registration information from among the 5G-GUTIs allocated via 3GPP access. The terminal may include the selected 5G-GUTI in a Registration Request message.

[0572] This specification may have various effects.

[0573] For example, registration based on Dual 3GPP access can be supported.

[0574] The effects that can be achieved through the specific examples of this specification are not limited to the effects listed above. For example, a person with ordinary skill in the relevant technical field may understand or derive various technical effects from this specification. Accordingly, the specific effects of this specification are not limited to those explicitly described herein, but may include various effects that can be understood or derived from the technical features of this specification.

[0575] For reference, the operation of the terminal (e.g., UE) described in this specification may be implemented by the devices of FIGS. 1 to 3 described above. For example, the terminal may be the first device (100) or the second device (200) of FIG. 2. For example, the operation of the terminal described in this specification may be processed by one or more processors (102 or 202). The operation of the terminal described in this specification may be stored in one or more memories (104 or 204) in the form of instructions / programs (e.g., instructions, executable codes) executable by one or more processors (102 or 202). The one or more processors (102 or 202) may control one or more memories (104 or 204) and one or more transceivers (105 or 206), and execute the instructions / programs stored in one or more memories (104 or 204) to perform the operation of the terminal (e.g., UE) described in the disclosure of this specification.

[0576] Additionally, the commands for performing the operations of the terminal described in the disclosure of this specification may be stored in a non-volatile computer-readable storage medium. The storage medium may be included in one or more memories (104 or 204). In addition, the commands recorded in the storage medium may be executed by one or more processors (102 or 202) to perform the operations of the terminal described in the disclosure of this specification.

[0577] For reference, the operations of a network node (e.g., AMF, SMF, UPF, UDM, H-PCF, NEF, AF, UDR, AUSF, etc.) or a base station (e.g., NG-RAN, gNB, RAN, (R)AN, etc.) described in this specification may be implemented by the devices of FIGS. 1 to 3 described below. For example, the network node or the base station may be the first device (100) or the second device (200) of FIG. 2. For example, the operations of the network node or the base station described in this specification may be processed by one or more processors (102 or 202). The operations of the terminal described in this specification may be stored in one or more memories (104 or 204) in the form of instructions / programs (e.g., instructions, executable codes) executable by one or more processors (102 or 202). One or more processors (102 or 202) may control one or more memories (104 or 204) and one or more transceivers (106 or 206), and execute instructions / programs stored in one or more memories (104 or 204) to perform operations of a network node or base station as described in the disclosure of this specification.

[0578] Additionally, the instructions for performing the operations of the network node or base station described in the disclosure of this specification may be stored in a non-volatile (or non-transitory) computer-readable storage medium having the instructions recorded thereon. The storage medium may be included in one or more memories (104 or 204). In addition, the instructions recorded in the storage medium may be executed by one or more processors (102 or 202) to perform the operations of the network node or base station described in the disclosure of this specification.

[0579] Although the preferred embodiments have been described above by way of example, the disclosure of this specification is not limited to such specific embodiments, and may be modified, changed, or improved in various forms within the scope described in the spirit and claims of this specification.

[0580] In the exemplary system described above, the methods are described based on a flowchart as a series of steps or blocks. However, the order of the steps described is not limited, and some steps may occur in a different order or simultaneously with other steps described above. Furthermore, those skilled in the art will understand that the steps depicted in the flowchart are not exclusive, and other steps may be included, or one or more steps in the flowchart may be deleted without affecting the scope of the invention.

[0581] The claims set forth in this specification may be combined in various ways. For example, the technical features of the method claims of this specification may be combined to implement a device, and the technical features of the device claims of this specification may be combined to implement a method. Furthermore, the technical features of the method claims and the technical features of the device claims of this specification may be combined to implement a device, and the technical features of the method claims and the technical features of the device claims of this specification may be combined to implement a method. Other implementations are within the scope of the claims.

Claims

1. In the method of Access and Mobility Management Function (AMF) performing communication, A step of receiving a registration request message including information related to dual registration from a User Equipment (UE); A step of transmitting a registration message including information related to the above double registration to Unified Data Management (UDM); Information related to the above dual registration prevents the UDM from sending a deregistration message to another AMF associated with the UE when the UDM allows dual registration; Receiving a response message from the UDM including information on whether the double registration is permitted; and A method comprising the step of transmitting a registration response message including information on whether the double registration was successful to the UE.

2. In paragraph 1, A method further comprising the step of transmitting information to the UE as to whether the AMF supports the dual registration.

3. In paragraph 1 or 2, A method characterized in that if the UDM does not allow the double registration, the response message includes error information.

4. In paragraph 1 or 2, The above registration response message is, A method characterized in that it includes information that the above double registration was successful.

5. In any one of paragraphs 1 to 4, A method further comprising the step of determining whether to allow the dual registration based on information on whether the dual registration is allowed and subscriber information of the UE obtained from the UDM.

6. In any one of paragraphs 1 to 5, A step of transmitting an authentication request message requesting authentication for the above UE to the Authentication Server Function (AUSF), The above authentication request message includes information related to dual registration; and A method characterized in that it further comprises the step of receiving an authentication response message from the AUSF.

7. In paragraph 6, A method characterized in that, if authentication for the UE is successful, the information related to the dual registration is used by the AUSF to transmit information to the UDM that the UE has requested dual registration.

8. In paragraph 6 or 7, A step of transmitting a security mode command message to the UE based on the reception of the authentication response message; and A method further comprising the step of receiving a security mode completion message from the UE.

9. In any one of paragraphs 1 to 8, If the above registration request message is a message based on mobility registration, a step of transmitting a request message requesting a UE context to the other AMF; The above request message includes information related to the double registration; and A method further comprising the step of receiving a UE context related to the dual registration from the other AMF based on the request message requesting the UE context including information related to the dual registration.

10. In the Access and Mobility Management Function (AMF) that performs communication, the AMF: One or more transmitters and receivers; one or more processors; and comprising one or more memories capable of storing instructions and being operable to the one or more processors; An operation performed based on the above command being executed by the one or more processors is an AMF method according to any one of claims 1 to 9.

11. In the method of User Equipment (UE) performing communication, A step of transmitting a registration request message containing information related to dual registration to the Access and Mobility Management Function (AMF); The information related to the above dual registration is used to prevent the Unified Data Management (UDM) from sending a deregistration message to another AMF associated with the UE when the UDM allows dual registration for the UE; and A method comprising the step of receiving a registration response message from the AMF, the registration response message including information on whether the double registration was successful.

12. In paragraph 11, A method further comprising the step of receiving information from the AMF as to whether the AMF supports the dual registration.

13. In paragraph 11 or 12, A method further comprising the step of determining to which AMF to transmit the registration request message including information related to the dual registration, based on capability information received from one or more AMFs including the AMF.

14. In any one of paragraphs 11 to 13, The above registration response message further includes information indicating a primary 5G-GUTI among multiple 5G-GUTIs allocated to the UE, A method further comprising the step of transmitting a registration request message including the primary 5G-GUTI to the non-3GPP access when performing registration via a non-3GPP access.

15. In any one of paragraphs 11 to 14, The above AMF is included in the VPLMN, A step of determining that the VPLMN does not support the dual registration based on the registration response message not including information on whether the dual registration was successful or including information that the dual registration is not supported; and A method further comprising the step of transmitting a registration request message including information related to the above double registration to the AMF of the HPLMN.

16. In a User Equipment (UE) configured to operate in a wireless communication system, the UE: One or more transmitters and receivers; one or more processors; and comprising one or more memories capable of storing instructions and being operable to the one or more processors; The actions performed based on the above instructions being executed by the one or more processors are: A UE according to any one of claims 11 to 15.

17. In the method of Unified Data Management (UDM) performing communication, A step of receiving a first registration message related to User Equipment (UE) from a second Access and Mobility Management Function (AMF); A step of receiving a second registration message including information related to dual registration for the UE from a second AMF; The information related to the above double registration prevents the UDM from sending a deregistration message to the first MF when the UDM allows double registration; a step of determining whether to allow the above double registration; and A method comprising the step of transmitting a response message to the second AMF including information on whether the double registration is permitted.

18. In paragraph 17, If the above double registration is not allowed, the response message includes error information, A method characterized in that it further comprises the step of transmitting a deregistration message to the first AMF if the UDM does not allow the double registration.

19. In paragraph 17 or 18, Further comprising a step of receiving a request message including information related to authentication for the UE, a serving network name, and information related to the dual registration from an Authentication Server Function (AUSF), A method characterized in that it is determined whether to allow dual registration for the UE based on the request message and the registration message.

20. In Unified Data Management (UDM) performing communication, the UDM: One or more transmitters and receivers; one or more processors; and comprising one or more memories capable of storing instructions and being operable to the one or more processors; An operation performed based on the above command being executed by the one or more processors is a UDM method according to any one of claims 17 to 19.

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