Disaster roaming

Abstract

An embodiment of the present disclosure provides a method. The method may comprise the steps of: selecting, by a UE, a first PLMN for disaster roaming; and transmitting, by the UE, a first registration request message to a first network entity of the first PLMN.

Description

Disaster Roaming

[0001] This specification relates to mobile communication.

[0002] 3GPP (3rd Generation Partnership Project) LTE (Long-Term Evolution) is a technology designed to enable high-speed packet communication. Many methods have been proposed to achieve LTE goals, such as reducing costs for users and operators, improving service quality, expanding coverage, and increasing system capacity. As high-level requirements, 3GPP LTE demands reduced cost per bit, improved service availability, flexible use of frequency bands, a simple structure, open interfaces, and appropriate power consumption of terminals.

[0003] Work has begun at the ITU (International Telecommunication Union) and 3GPP to develop requirements and specifications for New Radio (NR) systems. 3GPP must identify and develop the technical components necessary to successfully standardize NR in a timely manner, satisfying both urgent market demands and the longer-term requirements presented by the ITU-R (ITU Radio communication sector) IMT (International Mobile Telecommunications)-2020 process. Furthermore, NR must be able to utilize any spectrum band up to at least 100 GHz so that it can be used for wireless communication even in the distant future.

[0004] NR targets a single technical framework that covers all deployment, usage, and requirements, including eMBB (enhanced Mobile Broadband), mMTC (massive Machine Type-Communications), and URLLC (Ultra-Reliable and Low Latency Communications). NR must be forward compatible by nature.

[0005] In disaster situations, it is necessary to support disaster roaming for terminals. However, according to conventional technology, there is a problem that disaster roaming for terminals is not effectively supported.

[0006] According to one embodiment of the present specification, a method is provided. The method may include the step of a UE selecting a first PLMN for disaster roaming; and the step of the UE transmitting a first registration request message to a first network entity of the first PLMN.

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

[0008] According to one embodiment of the present specification, a method is provided. The method may include the step of a first network entity of a first PLMN receiving a first registration request message from a UE.

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

[0010] FIG. 1 shows an example of a communication system to which the implementation of the present specification is applied.

[0011] FIG. 2 shows an example of a wireless device to which the implementation of the present specification applies.

[0012] FIG. 3 shows an example of a UE to which the implementation of the present specification applies.

[0013] FIG. 4 shows an example of a 5G system structure to which the implementation of the present specification is applied.

[0014] FIGS. 5 and FIGS. 6 illustrate examples of registration procedures to which the implementation of the present specification applies.

[0015] FIG. 7 illustrates an example of a procedure according to the first example of the present disclosure.

[0016] FIG. 8 illustrates an example of a procedure according to the second example of the present disclosure.

[0017] FIG. 9 illustrates an example of operations according to one embodiment of the disclosure of the present specification.

[0018] The following techniques, devices, and systems may 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 may be implemented through wireless technologies such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA may be implemented through 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 through wireless technologies such as IEEE (Institute of Electrical and Electronics Engineers) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, or E-UTRA (Evolved UTRA). UTRA is part of UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (Long-Term Evolution) is part of E-UMTS (Evolved UMTS) using E-UTRA.3GPP LTE uses OFDMA in the downlink (DL) and SC-FDMA in the uplink (UL). Evolutions of 3GPP LTE include LTE-A (Advanced), LTE-A Pro, and / or 5G NR (New Radio).

[0019] For convenience of explanation, the implementation of this specification is described primarily in relation to 3GPP-based wireless communication systems. However, the technical characteristics 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 3GPP-based wireless communication systems may be applied to other mobile communication systems.

[0020] 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.

[0021] In this specification, "A or B" may mean "only A," "only B," or "both A and B." Alternatively, in this specification, "A or B" may be interpreted as "A and / or B." For example, in this specification, "A, B or C" may mean "only A," "only B," "only C," or "any combination of A, B and C."

[0022] A slash ( / ) or a comma used in this specification may mean "and / or." For example, "A / B" may mean "A and / or B." Accordingly, "A / B" may mean "only A," "only B," or "both A and B." For example, "A, B, C" may mean "A, B or C."

[0023] 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 as synonymous with "at least one of A and B."

[0024] Additionally, in this specification, "at least one of A, B and C" may mean "only A," "only B," "only C," or "any combination of A, B and C." Furthermore, "at least one of A, B or C" or "at least one of A, B and / or C" may mean "at least one of A, B and C."

[0025] Additionally, parentheses used in this specification 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 (e.g., PDCCH)," "PDCCH" may be proposed as an example of "control information."

[0026] Technical features described individually within a single drawing in this specification may be implemented individually or simultaneously.

[0027] Although not limited thereto, the various descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this specification may be applied to various fields where wireless communication and / or connectivity between devices (e.g., 5G) is required.

[0028] The present specification will be described in more detail below with reference to the drawings. In the following drawings and / or description, the same reference numerals may refer to the same or corresponding hardware blocks, software blocks, and / or function blocks unless otherwise indicated.

[0029] FIG. 1 shows an example of a communication system to which the implementation of the present specification is applied.

[0030] The 5G usage scenario shown in FIG. 1 is merely an example, and the technical features of this specification may be applied to other 5G usage scenarios not shown in FIG. 1.

[0031] The three main requirement categories for 5G are (1) enhanced Mobile BroadBand (eMBB) category, (2) massive Machine Type Communication (mMTC) category, and (3) Ultra-Reliable and Low Latency Communications (URLLC) category.

[0032] Referring to FIG. 1, the 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 the network of the communication system (1), but the implementation of the present specification is not limited to a 5G system and may be applied to future communication systems beyond a 5G system.

[0033] The base station (200) and the network (300) can be implemented as wireless devices, and a specific wireless device can operate as a base station / network node in relation to another wireless device.

[0034] 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. Wireless devices (100a to 100f) may include, but are not limited to, robots (100a), vehicles (100b-1 and 100b-2), eXtended Reality (XR) devices (100c), portable devices (100d), home appliances (100e), Internet-Of-Things (IoT) devices (100f), and Artificial Intelligence (AI) devices / servers (400). For example, vehicles may include vehicles with wireless communication capabilities, autonomous vehicles, and vehicles capable of performing communication between vehicles. 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 HMDs (Head-Mounted Devices) and HUDs (Head-Up Displays) 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., smartwatches 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.

[0035] 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 PDA (Personal Digital Assistant), a PMP (Portable Multimedia Player), a navigation system, a slate PC, a tablet PC, an ultrabook, a vehicle, a vehicle with autonomous driving capabilities, 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 financial device), a security device, a weather / environment device, a 5G service-related device, or a device related to the Fourth Industrial Revolution.

[0036] Wireless devices (100a to 100f) can be connected to a network (300) through a base station (200). AI technology may be applied to the wireless devices (100a to 100f), and the wireless devices (100a to 100f) can be connected to an AI server (400) through 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) may communicate with each other through the base station (200) / network (300), but they may 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., V2V (Vehicle-to-Vehicle) / V2X (Vehicle-to-everything) communication). Also, IoT devices (e.g., sensors) can communicate directly with other IoT devices (e.g., sensors) or other wireless devices (100a to 100f).

[0037] Wireless communication / connections (150a, 150b, 150c) can be established between wireless devices (100a to 100f) and / or between wireless devices (100a to 100f) and base station (200) and / or between base station (200). Here, the wireless communication / connections 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 communication between base stations (150c) (e.g., relay, IAB (Integrated Access and Backhaul)). Through the wireless communication / connections (150a, 150b, 150c), wireless devices (100a to 100f) and 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, based on various proposals in this specification, at least some of the following may be performed: a process for setting various configuration information for transmitting / receiving wireless signals, a process for various signal processing (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), and a resource allocation process.

[0038] NR supports multiple numerologies or subcarrier spacings (SCS) to support various 5G services. For example, when the SCS is 15 kHz, it supports a wide area in traditional cellular bands; when the SCS is 30 kHz / 60 kHz, it supports dense-urban areas, lower latency, and wider carrier bandwidth; and when the SCS is 60 kHz or higher, it supports a bandwidth greater than 24.25 GHz to overcome phase noise.

[0039] The NR frequency band can be defined by two types of frequency ranges (FR1, FR2). The numerical values ​​of the frequency ranges may change. For example, the two types of frequency ranges (FR1, FR2) may be as shown in Table 1 below. For convenience of explanation, among the frequency ranges used in the NR system, FR1 may mean "sub 6GHz range" and FR2 may mean "above 6GHz range" and may be referred to as Millimeter Wave (mmW).

[0040] Frequency Range Definition Frequency Range Subcarrier Spacing FR1 450 MHz - 6000 MHz 15, 30, 60 kHz FR2 24 250 MHz - 52600 MHz 60, 120, 240 kHz

[0041] As described above, the numerical values ​​of the frequency range of the NR system may change. For example, FR1 may include a band of 410 MHz to 7125 MHz as shown in Table 2 below. For example, FR1 may include a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or higher. For example, the frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or higher included within FR1 may include an unlicensed band. The unlicensed band may be used for various purposes, for example, for communication for vehicles (e.g., autonomous driving).

[0042] Frequency Range Definition Frequency Range Subcarrier Spacing FR1 4 10 MHz - 7 125 MHz 15, 30, 60 kHz FR2 24 250 MHz - 5 2600 MHz 60, 120, 240 kHz

[0043] Here, the wireless communication technology implemented in the wireless device of this specification may include LTE, NR, and 6G, as well as NarrowBand IoT (NB-IoT) for low-power communication. For example, NB-IoT technology may be an example of Low Power Wide Area Network (LPWAN) technology and may be implemented according to standards such as LTE Cat NB1 and / or LTE Cat NB2, but is not limited to the names mentioned above. Additionally, or generally, the wireless communication technology implemented in the wireless device of this specification may perform communication based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and may be referred to by various names such as eMTC (enhanced MTC). For example, LTE-M technology may be implemented in 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 names mentioned above. Additionally or generally, wireless communication technology implemented in the wireless device of this specification may include at least one of ZigBee, Bluetooth, and / or LPWAN with consideration for low-power communication, and is not limited to the names mentioned above. For example, ZigBee technology may create Personal Area Networks (PANs) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and may be referred to by various names.

[0044] FIG. 2 shows an example of a wireless device to which the implementation of the present specification applies.

[0045] 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 example / service. For example, {the first wireless device (100) and the second wireless device (200)} may correspond to at least one of {wireless devices (100a–100f) and base station (200)}, {wireless devices (100a–100f) and wireless devices (100a–100f)} and / or {base station (200) and base station (200)} of FIG. 1. The first wireless device (100) and / or the second wireless device (200) may be composed of various components, devices / parts and / or modules.

[0046] 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).

[0047] 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 generally, the memory (104) may be placed outside the processing chip (101).

[0048] The processor (102) can control the memory (104) and / or the transceiver (106) and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed herein. For example, the processor (102) may process information within the memory (104) to generate a first information / signal and transmit a wireless signal containing the first information / signal through the transceiver (106). The processor (102) may receive a wireless signal containing a second information / signal through the transceiver (106) and process the second information / signal to store the obtained information in the memory (104).

[0049] Memory (104) may be connected to the processor (102) so as to be operable. Memory (104) may store various types of information and / or instructions. Memory (104) may store firmware and / or software code (105) that implements code, instructions, and / or a set of instructions that perform the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this specification when executed by the processor (102). For example, firmware and / or software code (105) may implement instructions that perform the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this specification when executed by the processor (102). For example, firmware and / or software code (105) may control the processor (102) to perform one or more protocols. For example, firmware and / or software code (105) may control the processor (102) to perform one or more wireless interface protocol layers.

[0050] Here, the processor (102) and memory (104) may be part of a communication modem / circuit / chip designed to implement RAT (e.g., LTE or NR). A transceiver (106) may be connected to the processor (102) and may transmit and / or receive a wireless signal through one or more antennas (108). Each transceiver (106) may include a transmitter and / or receiver. The transceiver (106) may be interchangeably used with an RF (Radio Frequency) unit. In this specification, the first wireless device (100) may represent a communication modem / circuit / chip.

[0051] 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).

[0052] 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 generally, the memory (204) may be placed outside the processing chip (201).

[0053] The processor (202) can control the memory (204) and / or the transceiver (206) and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed herein. For example, the processor (202) may process information within the memory (204) to generate a third information / signal and transmit a wireless signal containing the third information / signal through the transceiver (206). The processor (202) may receive a wireless signal containing a fourth information / signal through the transceiver (206) and process the fourth information / signal to store the obtained information in the memory (204).

[0054] Memory (204) may be connected to the processor (202) so as to be operable. Memory (204) may store various types of information and / or instructions. Memory (204) may store firmware and / or software code (205) that implements code, instructions, and / or sets of instructions that perform descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed in this specification when executed by the processor (202). For example, firmware and / or software code (205) may implement instructions that perform descriptions, functions, procedures, proposals, methods, and / or flowcharts disclosed in this specification when executed by the processor (202). For example, firmware and / or software code (205) may control the processor (202) to perform one or more protocols. For example, firmware and / or software code (205) may control the processor (202) to perform one or more wireless interface protocol layers.

[0055] 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 transmit and / or receive a wireless signal through one or more antennas (208). Each transceiver (206) may include a transmitter and / or receiver. The transceiver (206) may be interchangeably used with an RF unit. In this specification, the second wireless device (200) may represent a communication modem / circuit / chip.

[0056] 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 PHY (physical) layer, a MAC (Media Access Control) layer, an RLC (Radio Link Control) layer, a PDCP (Packet Data Convergence Protocol) layer, an RRC (Radio Resource Control) layer, and an SDAP (Service Data Adaptation Protocol) layer). One or more processors (102, 202) may generate one or more PDUs (Protocol Data Units), one or more SDUs (Service Data Units), messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this specification. One or more processors (102, 202) may generate a signal (e.g., baseband signal) including a PDU, SDU, message, control information, data, or information according to the description, function, procedure, proposal, method, and / or operation flowchart disclosed in this specification and provide it to one or more transceivers (106, 206). One or more processors (102, 202) may receive a signal (e.g., baseband signal) from one or more transceivers (106, 206) and may obtain a PDU, SDU, message, control information, data, or information according to the description, function, procedure, proposal, method, and / or operation flowchart disclosed in this specification.

[0057] One or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, and / or a microcomputer. 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 one or more processors (102, 202). For example, one or more processors (102, 202) may be composed of a set of communication control processors, application processors (APs), electronic control units (ECUs), central processing units (CPUs), graphic processing units (GPUs), and memory control processors. One or more memories (104, 204) may be connected to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. One or more memories (104, 204) may be composed of Random Access Memory (RAM), Dynamic RAM (DRAM), Read-Only Memory (ROM), Erasable Programmable ROM (EPROM), flash memory, volatile memory, non-volatile memory, hard drive, register, cache memory, computer read storage media, and / or combinations thereof.One or more memories (104, 204) may be located inside and / or outside of one or more processors (102, 202). Additionally, one or more memories (104, 204) may be connected to one or more processors (102, 202) through various technologies such as wired or wireless connections.

[0058] One or more transceivers (106, 206) may transmit user data, control information, wireless signals / channels, etc., as described in the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this specification to one or more other devices. One or more transceivers (106, 206) may receive user data, control information, wireless signals / channels, etc., as described in the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this specification from one or more other devices. For example, one or more transceivers (106, 206) may be connected to one or more processors (102, 202) and may transmit and receive wireless signals. For example, one or more processors (102, 202) may 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) can control one or more transceivers (106, 206) to receive user data, control information, wireless signals, etc. from one or more other devices.

[0059] One or more transceivers (106, 206) may be connected to one or more antennas (108, 208). Additionally and / or generally, 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., mentioned in the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed herein through one or more antennas (108, 208). In this specification, one or more antennas (108, 208) may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports).

[0060] One or more transceivers (106, 206) can convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process received user data, control information, wireless signals / channels, etc. using one or more processors (102, 202). One or more transceivers (106, 206) can convert processed user data, control information, wireless signals / channels, etc. from baseband signals to RF band signals using one or more processors (102, 202). To this end, one or more transceivers (106, 206) may include (analog) oscillators and / or filters. For example, one or more transceivers (106, 206) can up-convert an OFDM baseband signal into an OFDM signal through 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) can receive an OFDM signal at a carrier frequency and down-convert the OFDM signal into an OFDM baseband signal through an (analog) oscillator and / or filter under the control of one or more processors (102, 202).

[0061] Although not illustrated in FIG. 2, the wireless device (100, 200) may 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., audio I / O port, video I / O port), a driving unit, and a computing unit. The additional components (140) may be connected to one or more processors (102, 202) through various technologies, such as wired or wireless connections.

[0062] In an implementation of the present specification, the UE may operate as a transmitting device in the uplink and as a receiving device in the downlink. In an implementation of the present specification, the base station may operate as a receiving device in the UL and as a transmitting device in the DL. For technical convenience, it is generally assumed 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 to the first wireless device (100) may be configured to perform UE operations according to an implementation of the present specification or to control a transceiver (106) to perform UE operations according to an implementation of the present specification. A processor (202) connected to, mounted on, or released to the second wireless device (200) may be configured to perform base station operations according to an implementation of the present specification or to control a transceiver (206) to perform base station operations according to an implementation of the present specification.

[0063] In this specification, the base station may be referred to as Node B, eNode B, or gNB.

[0064] FIG. 3 shows an example of a UE to which the implementation of the present specification applies.

[0065] Referring to FIG. 3, the UE (100) can correspond to the first wireless device (100) of FIG. 2.

[0066] The UE (100) includes a processor (102), memory (104), 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).

[0067] The processor (102) may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operation 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 operation flowcharts disclosed herein. Layers of a wireless 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 processor, EXYNOS made by Samsung® TM Series processors, A Series processors made by Apple®, HELIO made by MediaTek® TM Series processors, ATOM made by Intel® TM It can be found in series processors or corresponding next-generation processors.

[0068] Memory (104) is coupled to the processor (102) so as to be operable and stores various information for operating the processor (102). Memory (104) may include ROM, RAM, flash memory, memory card, storage medium and / or other storage device. When the implementation is implemented in software, the technology described herein may be implemented using modules (e.g., procedures, functions, etc.) that perform the descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed herein. Modules may be stored in memory (104) and executed by the processor (102). Memory (104) may be implemented within the processor (102) or outside the processor (102), in which case it may be communicatively coupled to the processor (102) through various methods known in the technology.

[0069] A transceiver (106) is coupled to operate with a processor (102) and transmits and / or receives a wireless signal. The transceiver (106) includes a transmitter and a receiver. The transceiver (106) may include a baseband circuit for processing a wireless frequency signal. The transceiver (106) controls one or more antennas (108) to transmit and / or receive a wireless signal.

[0070] 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).

[0071] The display (143) outputs the result 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).

[0072] A SIM card (145) is an integrated circuit for securely storing an International Mobile Subscriber Identity (IMSI) and associated keys, and is used to identify and authenticate a subscriber in a mobile device such as a mobile phone or computer. Additionally, contact information can be stored on many SIM cards.

[0073] 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).

[0074] FIG. 4 shows an example of a 5G system structure to which the implementation of the present specification is applied.

[0075] The 5G system (5GS) structure consists of the following network functions (NF).

[0076] - AUSF (Authentication Server Function)

[0077] -AMF (Access and Mobility Management Function)

[0078] - DN (Data Network), for example, operator services, internet access, or third-party services

[0079] - USDF (Unstructured Data Storage Function)

[0080] - NEF (Network Exposure Function)

[0081] - I-NEF (Intermediate NEF)

[0082] - NRF (Network Repository Function)

[0083] - NSSF (Network Slice Selection Function)

[0084] - PCF (Policy Control Function)

[0085] - SMF (Session Management Function)

[0086] - UDM (Unified Data Management)

[0087] - UDR (Unified Data Repository)

[0088] - UPF (User Plane Function)

[0089] - UCMF (UE radio Capability Management Function)

[0090] - AF (Application Function)

[0091] - UE (User Equipment)

[0092] - (R)AN ((Radio) Access Network)

[0093] - 5G-EIR (5G-Equipment Identity Register)

[0094] - NWDAF (Network Data Analytics Function)

[0095] - CHF (CHarging Function)

[0096] 또한, 다음과 같은 네트워크 기능이 고려될 수 있다.

[0097] - N3IWF (Non-3GPP InterWorking Function)

[0098] - TNGF (Trusted Non-3GPP Gateway Function)

[0099] - W-AGF (Wireline Access Gateway Function)

[0100] Figure 4 shows the 5G system structure in a non-roaming case using a reference point representation showing how various network functions interact with each other.

[0101] In Figure 4, UDSF, NEF, and NRF are not described for clarity of the point-to-point diagram. However, all network functions shown can interact with UDSF, UDR, NEF, and NRF as needed.

[0102] 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.

[0103] The 5G system structure includes the following reference points.

[0104] - N1: Reference point between UE and AMF.

[0105] - N2: Reference point between (R)AN and AMF.

[0106] - N3: Reference point between (R)AN and UPF.

[0107] - N4: Reference point between SMF and UPF.

[0108] - N6: Reference point between the UPF and the data network.

[0109] - N9: Reference point between two UPFs.

[0110] The following reference points show the interactions that exist between the NF services of NF.

[0111] - N5: Reference point between PCF and AF.

[0112] - N7: Reference point between SMF and PCF.

[0113] - N8: Reference point between UDM and AMF.

[0114] - N10: Reference point between UDM and SMF.

[0115] - N11: Reference point between AMF and SMF.

[0116] - N12: Reference point between AMF and AUSF.

[0117] - N13: Reference point between UDM and AUSF.

[0118] - N14: Reference point between two AMFs.

[0119] - N15: Reference point between PCF and AMF for non-roaming scenarios, reference point between PCF and AMF of the visited network for roaming scenarios.

[0120] - N16: Reference point between two SMFs (in the case of roaming, between the SMF of the visited network and the SMF of the home network)

[0121] - N22: Reference point between AMF and NSSF.

[0122] In some cases, two NFs may need to be connected to each other to service the UE.

[0123] The registration procedure is described. Refer to Section 4.2.2.2 of 3GPP TS 23.502 V16.3.0 (2019-12).

[0124] FIGS. 5 and FIGS. 6 illustrate examples of registration procedures to which the implementation of the present specification applies.

[0125] The 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.

[0126] - Initial registration for the 5GS; or

[0127] - Mobility registration update; or

[0128] - Periodic registration update; or

[0129] - Emergency registration

[0130] The general registration procedure of Figures 5 and 6 applies to all registration procedures described above, but the periodic registration update does not need to include all parameters used in other registration procedures.

[0131] The general registration procedure of Figures 5 and 6 is used when a UE is registered to a 3GPP connection when it is already registered to a non-3GPP connection, and vice versa. To register a UE to a 3GPP connection when it is already registered to a non-3GPP connection scenario, an AMF change may be required.

[0132] First, the procedure of Fig. 5 is explained.

[0133] (1) Step 1: The UE sends a Registration Request message to the (R)AN. The Registration Request message corresponds to the AN message.

[0134] A registration request message may include AN parameters. For NG-RAN, AN parameters include, for example, 5G-S-TMSI (5G SAE temporary mobile subscriber identity) or GUAMI (globally unique AMF ID), a selected PLMN (public land mobile network) ID (or PLMN ID and NID (network identifier)), and requested NSSAI (Requested network slice selection assistance information). AN parameters also include an establishment cause. The establishment cause provides the reason for requesting the 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.

[0135] The registration request message may include a registration type. The registration type indicates whether the UE wants to perform an initial registration (e.g., the UE is in the RM-DEREGISTERED state), or a mobility registration update (e.g., the UE is in the RM-REGISTERED state and initiates the registration process because the UE moves, or the UE wants to update a capability or protocol parameter, or requests a change to the set of network slices allowed for the UE to use), or a periodic registration update (e.g., the UE is in the RM-REGISTERED state and initiates the registration process due to the expiration of the periodic registration update timer), or an urgent registration (e.g., the UE is in the restricted service state).

[0136] When a UE performs initial registration, the UE specifies the UE ID in the registration request message as follows, listed in order of decreasing priority.

[0137] i) If the UE has a valid EPS (evolved packet system) GUTI (globally unique temporary identifier), the 5G-GUTI mapped from the EPS GUTI;

[0138] ii) Native 5G-GUTI assigned by the PLMN for which the UE is attempting to register (if available);

[0139] iii) Native 5G-GUTI assigned by a PLMN equivalent to the PLMN for which the UE is attempting to register;

[0140] iv) Native 5G-GUTI assigned by other PLMNs (if available);

[0141] v) Otherwise, the UE includes SUCI (subscriber concealed identifier) ​​in the registration request message.

[0142] If the UE performing the initial registration has both a valid EPS GUTI and a native 5G-GUTI, the UE also marks the native 5G-GUTI as an additional GUTI. If one or more native 5G-GUTIs are available, the UE selects the 5G-GUTIs from items (ii)-(iv) in the list above in decreasing order of priority.

[0143] When the UE performs initial registration with native 5G-GUTI, the UE displays relevant GUAMI information in AN parameters. When the UE performs initial registration with SUCI, the UE does not display GUAMI information in AN parameters.

[0144] In the case of emergency registration, SUCI is included if the UE does not have a valid 5G-GUTI, and PEI is included if the UE does not have a SUPI (subscriber permanent identifier) ​​and does not have a valid 5G-GUTI. In other cases, a 5G-GUTI is included, which indicates the last serving AMF.

[0145] 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 established PDU session of the current PLMN in the UE.

[0146] (2) Step 2: (R)AN selects AMF.

[0147] If 5G-S-TMSI or GUAMI is not included, or if 5G-S-TMSI or GUAMI does not represent a valid AMF, (R)AN selects an AMF based on (R)AT and the requested NSSAI, where available.

[0148] If the UE is in the CM-CONNECTED state, (R)AN can forward a registration request message to the AMF based on the UE's N2 connection.

[0149] If (R)AN cannot select a suitable AMF, (R)AN performs AMF selection by forwarding a registration request message to the AMF configured in (R)AN.

[0150] (3) Step 3: (R)AN sends a registration request message to the new AMF. The registration request message corresponds to the N2 message.

[0151] The registration request message may include all information and / or part of the information contained in the registration request message received from the UE described in Step 1.

[0152] The registration request message may include N2 parameters. When NG-RAN is used, the N2 parameters include the selected PLMN ID (or PLMN ID and NID), location information and cell ID associated with the cell where the UE is camping, and a UE context request indicating that a UE context including security information in NG-RAN must be established. When NG-RAN is used, the N2 parameters also include the cause for establishment.

[0153] If the registration type indicated by the UE is a periodic registration update, steps 4-19 described below may be omitted.

[0154] (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 call the Namf_Communication_UEContextTransfer service operation on the previous AMF, including the full registration request NAS (non-access stratum) message to request the UE's SUPI and UE context.

[0155] (5) Step 5: The previous AMF can respond to the new AMF for the Namf_Communication_UEContextTransfer call, including the UE's SUPI and UE context.

[0156] (6) Step 6: If SUCI is not provided by the UE or is not retrieved from the previous AMF, the new AMF may initiate the identity request procedure by sending an identity request message to the UE to request SUCI.

[0157] (7) Step 7: The UE may respond with an Identity Response message containing SUCI. The UE derives SUCI using the provided public key of the home PLMN (HPLMN).

[0158] (8) Step 8: The new AMF may decide to call AUSF to initiate UE authentication. In this case, the new AMF selects AUSF based on SUPI or SUCI.

[0159] (9) Step 9: Authentication / security may be established by UE, new AMF, AUSF and / or UDM.

[0160] (10) Step 10: If the AMF is changed, the new AMF may call the Namf_Communication_RegistrationCompleteNotify service operation to notify the previous AMF that UE registration is complete for the new AMF. If the authentication / security procedure fails, registration is rejected and the new AMF may call the Namf_Communication_RegistrationCompleteNotify service operation with a reject indication reason code for the previous AMF. The previous AMF may continue as if no UE context passing service operation was received.

[0161] (11) Step 11: If the PEI is not provided by the UE or has not been retrieved from the previous AMF, the new AMF may initiate an Identity Request procedure by sending an Identity Request message to the UE to retrieve the PEI. The PEI is transmitted in encryption, except in cases where the UE cannot perform emergency registration and be authenticated.

[0162] (12) Step 12: Optionally, the new AMF can call the N5g-eir_EquipmentIdentityCheck_Get service operation to start ME ID checking.

[0163] Now, the procedure of Fig. 6 following the procedure of Fig. 5 is explained.

[0164] (13) Step 13: If you perform Step 14 below, the new AMF can select a UDM based on SUPI, and the UDM can select a UDR instance.

[0165] (14) Step 14: New AMFs can be registered with UDM.

[0166] (15) Step 15: The new AMF can select PCF.

[0167] (16) Step 16: The new AMF may optionally establish / modify AM policy associations.

[0168] (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.

[0169] (18) Step 18: If the new AMF and the previous AMF are in the same PLMN, the new AMF can send a request to modify the UE context to N3IWF / TNGF / W-AGF.

[0170] (19) Step 19: N3IWF / TNGF / W-AGF can send a UE context modification response to the new AMF.

[0171] (20) Step 20: After the new AMF receives a response message from N3IWF / TNGF / W-AGF in Step 19, the new AMF can register with UDM.

[0172] (21) Step 21: The new AMF sends a Registration Accept message to the UE.

[0173] The new AMF sends a registration acceptance message to the UE indicating that the registration request has been accepted. If the new AMF assigns a new 5G-GUTI, the 5G-GUTI is included. If the UE is already in the RM-REGISTERED state via another connection on the same PLMN, the UE uses the 5G-GUTI received in the registration acceptance message for both registrations. If the registration acceptance message does not include a 5G-GUTI, the UE uses the 5G-GUTI assigned to the existing registration for the new registration as well. If the new AMF assigns a new registration area, it transmits the registration area to the UE via the registration acceptance message. If the registration acceptance message does not contain a registration area, the UE considers the previous registration area to be valid. Mobility Restrictions are included when mobility restrictions apply to the UE and the registration type is not an urgent registration. The new AMF indicates the PDU session 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 connects to two AMFs belonging to different PLMNs via a 3GPP connection and a non-3GPP connection, the UE locally removes internal resources associated with the PDU session of the current PLMN that are not indicated as established in the received PDU session state. If PDU session state information is present in the registration acceptance message, the new AMF instructs the UE on the PDU session state.

[0174] The Allowed NSSAI provided in the registration acceptance message is valid in the registration area and applies to all PLMNs having a tracking area included in the registration area. The Mapping of Allowed NSSAI is to map the HPLMN S-NSSAI to each S-NSSAI of the Allowed NSSAI. The Mapping of Configured NSSAI is to map the HPLMN S-NSSAI to each S-NSSAI of the Configured NSSAI for the serving PLMN.

[0175] Additionally, the new AMF optionally performs UE policy association establishment.

[0176] (22) Step 22: If the UE succeeds in updating itself, it can send a Registration Complete message to the new AMF.

[0177] The UE can send a registration completion message to the new AMF to check if a new 5G-GUTI has been assigned.

[0178] (23) Step 23: In the case of registration via a 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 the case of registration via a non-3GPP connection, if the UE is in a CM-CONTENED state on the 3GPP connection, the new AMF may send RRC Inactive Assistance information to the NG-RAN.

[0179] (24) Step 24: AMF can perform information updates on UDM.

[0180] (25) Step 25: The UE can execute network slice-specific authentication and authorization (NSSAA) procedures.

[0181] In disaster situations, it is necessary to support disaster roaming for terminals. However, according to conventional technology, there is a problem that disaster roaming for terminals is not effectively supported.

[0182] According to 3GPP TS22.280 V19.6.0, Mission Critical services were discussed.

[0183] Mission Critical: A quality or characteristic of a communication activity, application, service, or device. Mission critical may require low setup and low transmission latency, high availability and high reliability, the ability to handle a large number of users and devices, strong security, and strong priority and preemptive processing capabilities.

[0184] For terminals using mission-critical services, fast and / or efficient processing is required, so it may be necessary to assign high priority to these terminals to process them quickly.

[0185] 3GPP TS24.501 V18.8.0 defines MINT. MINT stands for Minimization of Service Interruption.

[0186] The contents of 3GPP TS24.501 V18.8.0 S4.5.2 are explained. For the following description, 3GPP TS24.501 V18.8.0 S4.5.2 may be referenced.

[0187] 4.5.2 Determination of the access identities and access category associated with a request for access for UEs not operating in SNPN access operation mode over 3GPP access

[0188] A UE may initiate an access attempt based on one of the events listed in 3GPP TS24.501 V18.8.0 S4.5.1. In this case, the UE may determine one or more access identities to be associated with the access attempt from a set of standardized access identities, and determine one access category to be associated with the access attempt from a set of standardized access categories and a set of operator-defined access categories.

[0189] The set of access identities applicable to a disaster request can be determined by the UE in the following ways:

[0190] a) For each of Access Identity 1, 2, 3, 11, 12, 13, 14, and 15 in Table 3, the UE can determine if the Access Identity is applicable in the selected PLMN if a new Public Land Mobile Network (PLMN) is selected; otherwise, the UE can determine if the Access Identity is applicable in a Registered PLMN (RPLMN) or an equivalent PLMN; and

[0191] b) If none of the above access identities apply, access identity 0 may be applied.

[0192] Access Identity Number UE Configuration 0 For UE, no parameters from this table are configured. (UE is not configured with any parameters from this table) 1 (NOTE 1) UE is configured for multimedia priority service (MPS). (UE is configured for multimedia priority service (MPS) 2 (NOTE 2) UE is configured for mission critical service (MCS). (UE is configured for mission critical service (MCS))3 (NOTE 4) UE for which a disaster condition applies 4-10 Reserved for future use 11 (NOTE 3) Access Class 11 is configured in the UE 12 (NOTE 3) Access Class 12 is configured in the UE 13 (NOTE 3) Access Class 13 is configured in the UE 14 (NOTE 3) Access Class 14 is configured in the UE 15 (NOTE 3) Access Class 15 is configured in the UE.) NOTE 1: Access Identity 1 is valid under the following conditions: - Universal Subscriber Identity Module (USIM) file EF UAC_AICa indicates that for the UE, Access Identity 1 and the selected PLMN (if a new PLMN is selected) or RPLMN is set to an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists) or the visiting PLMN of the home country. For reference, EF UAC_AIC EF stands for Elementary File, UAC for Unified Access Control, and AIC for Access Identities Configuration. ;- When the UE receives a 5GS Network Function Support Information Element (IE) from an RPLMN with the MPS Indicator bit set to "Access Identity 1 Valid" as specified in 3GPP TS24.501 V18.8.0 S5.5.1.2.4 and S5.5.1.3.4; or- When the UE receives a Priority Indicator IE from an RPLMN with the MPS Indicator bit set to "Access Identity 1 Valid" as specified in 3GPP TS24.501 V18.8.0 S5.4.4.3. NOTE 2: Access Identity 2 is used in a UE with MCS configured and is valid under the following conditions:- USIM file EF UAC_AICa. When indicating to the UE that Access Identity 2 and the selected PLMN (if a new PLMN is selected) or RPLMN is set to an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists) or the visiting PLMN of the home country; - when the UE receives a 5GS network feature support IE from the RPLMN where the MCS indicator bit is set to "Access Identity 2 valid" as specified in 3GPP TS24.501 V18.8.0 S5.5.1.2.4 and 3GPP TS24.501 V18.8.0 S5.5.1.3.4; OR—when the UE receives a Priority Indicator IE from the RPLMN with the MCS indicator bit value set to "Access Identity 2 Valid" as specified in 3GPP TS24.501 V18.8.0 S5.4.4.3. NOTE 3: Access identities 11 and 15 are valid in the HPLMN (if the EHPLMN list does not exist or is empty) or the EHPLMN (if the EHPLMN list exists). Access identities 12, 13, and 14 are valid only in the HPLMN and the visiting PLMN of the home country. NOTE 4: Access identity 3 is valid when the UE is enrolled in or registered for disaster roaming services (see 3GPP TS 23.122 V18.7.0).

[0193] Table 3 shows examples of access identities.

[0194] The UE determines whether Access Identity 1 is valid using the MPS indicator bit of the 5GS Network Function Support IE or the Priority Indicator IE. The handling of the MPS indicator bit of the 5GS Network Function Support IE within the REGISTRATION ACCEPT message is described in Sections 5.5.1.2.4 and 5.5.1.3.4 of TS24.501 V18.8.0. The handling of the MPS indicator bit included in the Priority Indicator IE of the CONFIGURATION UPDATE COMMAND message is described in Section 5.4.4.3 of TS24.501 V18.8.0.

[0195] The UE does not belong to an HPLMN (if the EHPLMN list does not exist or is empty), an EHPLMN (if the EHPLMN list exists), or a visited PLMN of the home country, and the USIM file EF UAC_AIC This may indicate that the UE is set to Access ID 1. In this case, the UE must not consider Access Identity 1 to be valid until it receives the MPS indicator bit within the 5GS network function support IE of the REGISTRATION ACCEPT message or the priority indicator IE of the CONFIGURATION UPDATE COMMAND message from the RPLMN or equivalent PLMN that Access Identity 1 is set to "Access Identity 1 Valid".

[0196] When the UE is in an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists) or is in a visiting PLMN of the home country, the UE has the USIM file EF specified in 3GPP TS 31.102 V18.7.0 UAC_AICBased on the contents of and the rules specified in Table 3, the applicability of Access Identity 1 can be determined. When the UE is in an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists) or a visiting PLMN of the home country, USIM file EF UAC_AIC If it does not indicate that the UE is set to Access ID 1, the UE determines the validity of Access Identity 1 using the MPS indicator bit of the 5GS Network Function Support IE in the REGISTRATION ACCEPT message or the Priority Indicator IE in the CONFIGURATION UPDATE COMMAND message. If the UE is located in an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists) or a local visiting PLMN, and the USIM file EF UAC_AIC If it indicates that the UE is set to Access ID 1, the MPS indicator bits and Priority indicator IE of the 5GS Network Function Support IE are not applicable. When the UE is not in an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists) or a visiting PLMN of the home country, the USIM file EF UAC_AIC The content of is not applicable.

[0197] The UE determines the validity of Access Identity 2 using the MCS indicator bits of the 5GS Network Function Support IE or the Priority Indication IE. The handling of the MCS indicator bits of the 5GS Network Function Support IE within the REGISTRATION ACCEPT message is described in Sections 5.5.1.2.4 and 5.5.1.3.4 of TS24.501 V18.8.0. The handling of the MCS indicator bits included in the Priority Indication IE of the CONFIGURATION UPDATE COMMAND message is described in Section 5.4.4.3 of TS24.501 V18.8.0. The UE does not belong to an HPLMN (if the EHPLMN list does not exist or is empty), an EHPLMN (if the EHPLMN list exists), or a visiting PLMN of the home country, and the USIM file EF UAC_AIC This may indicate that the UE is set to Access Identity 2. In this case, the UE must not consider Access Identity 2 to be valid until it receives the MCS indicator bit in the 5GS network function setting IE of the REGISTRATION ACCEPT message or the priority indicator IE of the CONFIGURATION UPDATE COMMAND message from the RPLMN or equivalent PLMN that Access Identity 2 is set to "Enabled".

[0198] When the UE is in an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists), or is in a visiting PLMN of its own country, the USIM file EF specified in 3GPP TS 31.102 V18.7.0 UAC_AICDetermine the applicability of Access Identity 2 using the contents of and the rules specified in Table 3. When the UE is in an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists) or a visiting PLMN of the home country, USIM file EF UAC_AIC It may not indicate that the UE is set to Access Identity 2. In this case, the UE determines the validity of Access Identity 2 using the MCS indicator bit of the 5GS Network Function Support IE of the REGISTRATION ACCEPT message or the Priority Indicator IE of the CONFIGURATION UPDATE COMMAND message. If the UE is located in an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists) or a visiting PLMN of the home country, and the USIM file EF UAC_AIC If it indicates that the UE is set to Access Identity 2, the MCS indicator bits and priority indicator IE of the 5GS Network Function Support IE do not apply. When the UE is not in an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists) or a visiting PLMN of the home country, the USIM file EF UAC_AIC The content of does not apply.

[0199] The UE determines the validity and applicability of Access Identity 3 by checking the conditions specified in Section 4.4.3.1.1 of 3GPP TS 23.122 V19.0.0.

[0200] When the UE is in an HPLMN (if the EHPLMN list does not exist or is empty) or an EHPLMN (if the EHPLMN list exists), the USIM file EF specified in 3GPP TS 31.102 V18.7.0 ACCThe applicability of access classes 11 and 15 is determined using the contents and the rules specified in Table 3. Access classes 11 and 15 do not apply when the UE is not in an HPLMN (if the EHPLMN list is missing or empty) or an EHPLMN (if the EHPLMN list exists).

[0201] When the UE is in an HPLMN or a local visiting PLMN, the USIM file EF specified in 3GPP TS 31.102 V18.7.0 ACC The applicability of access classes 12–14 is determined using the contents of and the rules specified in Table 3. If the UE does not belong to an HPLMN or a visited PLMN, access classes 12–14 do not apply.

[0202] To determine the applicable access category for an access attempt, the NAS (e.g., the UE's NAS tier) checks the rules in Table 4.5.2.2 and uses the matching access category during the barring check. If an access attempt matches one or more rules, the access category with the lowest rule number must be selected. If an access attempt matches one or more operator-defined access category definitions, the UE must select an access category from the operator-defined access category with the lowest priority value (see Section 4.5.3 of TS24.501 V18.8.0).

[0203] This describes MINT (Minimization of service interruption). In this regard, TS24.501 V18.8.0 S4.24 Minimization of service interruption may be referenced.

[0204] The UE and the network can support Minimization of service interruption (MINT). MINT aims to enable the UE to obtain services from a PLMN that provides disaster roaming services to a UE-determined PLMN based on disaster conditions.

[0205] If the UE supports MINT, the indication of whether disaster roaming is enabled within the UE, the indication of the applicability of the "list of PLMNs to be used in disaster conditions" provided by the VPLMN, one or more "lists of PLMN(s) to be used in disaster conditions," the disaster roaming wait range and disaster return wait range provided by the network (if available) are stored in the non-volatile memory of the ME as specified in Appendix C of TS24.501 V18.8.0 and are retained when the UE enters the 5GMM-DEREGISTERED state. Appendix C of TS24.501 V18.8.0 specifies the conditions under which the indication of whether disaster roaming is enabled within the UE, the indication of the "applicability of the list of PLMN(s) to be used in disaster conditions" provided by the VPLMN, one or more "lists of PLMNs to be used in disaster conditions" stored in the ME, the disaster roaming wait range and the disaster return wait range are deleted.

[0206] When a UE selects a PLMN for disaster roaming as specified in 3GPP TS 23.122 V19.0.0:

[0207] a) If there is no disaster roaming standby range stored in the UE, the UE performs the registration procedure for disaster roaming services in the selected PLMN as described in Section 5.5.1 of TS24.501 V18.8.0; and

[0208] b) If the UE has a saved disaster roaming standby range, the UE generates a random number within the disaster roaming standby range and starts a timer with the generated random number. While the timer is running, the UE does not initiate registration for the selected PLMN. An exception applies if the UE needs to request an emergency Protocol Data Unit (PDU) (or Packet Data Unit) session; in this case, the UE must initiate the registration procedure, set the 5GS registration type IE to "Emergency Registration" in the REGISTRATION REQUEST message, and continue running the timer. When the timer expires, if the UE does not have an emergency PDU session and the UE is still camped on the selected PLMN, the UE must perform the registration procedure for the disaster roaming service described in Section 5.5.1 of TS24.501 V18.8.0. If the UE has an emergency PDU session when the timer expires and the UE is maintaining a camping state on the selected PLMN, the UE performs the disaster roaming service registration procedure described in Section 5.5.1 of TS24.501 V18.8.0 after releasing the emergency PDU session.

[0209] If the UE is powered off while the disaster roaming standby range timer is running, and the UE is powered back on while the USIM within the UE remains the same and the UE selects a PLMN for disaster roaming, the UE behaves as follows:

[0210] - Let t1 be the remaining time of the disaster roaming standby range timer at the time the power is turned off, and let t be the time elapsed from the time the power is turned off until the time it is turned on again. If t1 is greater than t, the timer must be restarted with t1 - t. If t1 is less than or equal to t, a timer restart is not necessary. If the UE is unable to determine t, the UE must restart the timer with t1.

[0211] If the UE determines that the disaster state has ended as specified in 3GPP TS 23.122 V19.0.0:

[0212] a) If a timer started with a random number generated within the disaster roaming standby range is running, the UE must stop it;

[0213] b) The UE shall perform PLMN selection as specified in 3GPP TS 23.122 V18.7.0, except where the UE has already selected an acceptable PLMN as specified in 3GPP TS 23.122 V19.0.0; and

[0214] c) A UE in a disaster state may select a PLMN determined by the UE and there may be a stored disaster return waiting range. In this case, the stored disaster return waiting range is provided by 1) 1) a PLMN providing disaster roaming services; or 2) a selected PLMN.

[0215] The UE generates a random number within the disaster return waiting range, starts a timer with the generated random number value, and enters the 5GMM-DEREGISTERED.ATTEMPTING-REGISTRATION state or the 5GMM-REGISTERED.ATTEMPTING-REGISTRATION-UPDATE state if registered. While the timer is running, the UE must not initiate the registration procedure on the selected PLMN. An exception applies if the UE needs to request an emergency PDU session; in this case, the UE initiates the registration procedure, sets the 5GS registration type IE to "Emergency Registration" in the REGISTRATION REQUEST message, and continues the timer. When the timer expires, if the UE does not have an emergency PDU session, the UE must perform the registration procedure if it is still camp-on on the selected PLMN. When the timer expires, if the UE has an emergency PDU session and the UE remains camp-on on the selected PLMN, the UE releases the emergency PDU session and performs the registration procedure described in Section 5.5.1 of TS24.501 V18.8.0.

[0216] Otherwise, the UE performs the registration procedure in the selected PLMN.

[0217] If the UE is off while the disaster return standby range timer is running, when the UE is turned on, the USIM within the UE is identical, and the UE selects the PLMN determined by the disaster-state UE, the UE behaves as follows:

[0218] Let t1 be the remaining time of the disaster recovery waiting range timeout timer when the switch is off, and let t be the elapsed time between the switch off and the switch on. If t1 is greater than t, the timer is restarted with t1 - t. If t1 is less than or equal to t, there is no need to restart the timer. If the UE is unable to determine t, the UE restarts the timer with t1.

[0219] When an AMF assigns a registration area to a UE registered for a disaster roaming service, the AMF may include only a Tracking Area Identifier (TAI) that includes the area where the disaster occurred.

[0220] If the AMF determines that the disaster situation has ended and a UE registered with the disaster roaming service holds an emergency PDU session, the AMF initiates the standard UE configuration update procedure to indicate that the UE is registered with the emergency service, as specified in Section 5.4.4.2 of TS24.501 V18.8.0.

[0221] For UEs registered with the disaster roaming service, interoperability with EPS is not supported. Upon registering with the disaster roaming service, the UE indicates to the network that it does not support S1 mode as specified in Section 5.5.1.2.2 of TS24.501 V18.8.0. If emergency PDU session setup or emergency service fallback is required while registered with the disaster roaming service, the UE initiates the registration process for mobility and periodic registration updates and indicates that it supports S1 mode as specified in Section 5.5.1.3.2 of TS24.501 V18.8.0.

[0222] If a UE is registered for disaster roaming services and a registered PLMN has been removed from the prohibited PLMN list for reasons specified in Section 4.4.6 of 3GPP TS 23.122 V18.7.0 or Appendix C of 3GPP TS 23.122 V18.7.0, the UE must initiate the deregistration procedure and perform PLMN selection as specified in 3GPP TS 23.122 V19.0.0.

[0223] TS24.501 V18.8.0 S9.11.3.84 explains an example of a Registration wait range.

[0224] The purpose of the registration standby range information element is to provide the UE with a disaster roaming standby range and / or a disaster return standby range.

[0225] The registration waiting range information element is coded as shown in Tables 4 and 5.

[0226] The registration waiting range is a type 4 information element of 4 octets in length.

[0227] 87654321 Registration wait range IEI Octet 1 Length of registration wait range Octet 2 Minimum registration wait time Octet 3 Maximum registration wait time Octet 4

[0228] Table 4 is an example of a Registration wait range information element.

[0229] Minimum registration wait time (octet 3) The minimum registration wait time includes the minimum duration of the registration wait time encoded in octet 2 of the General Packet Radio Service (GPRS) timer information element (see 3GPP TS 24.008 Section 10.5.7.3). Maximum registration wait time (octet 4) The maximum registration wait time includes the maximum duration of the registration wait time encoded in octet 2 of the GPRS timer information element (see 3GPP TS 24.008 Section 10.5.7.3).

[0230] Table 5 is an example of a Registration wait range information element. The contents of Table 5 explain the minimum and maximum registration wait times in Table 4.

[0231] The MINT (Minimization of service Interruption) feature, which enables a terminal to connect to another network via disaster roaming and perform services when it cannot connect to its subscribed network due to a disaster, has been studied in Rel-17 and Rel-18 and is currently being studied as a study item in Rel-19. According to prior art (e.g., 24.501 spec), a procedure has been studied in which, when a disaster occurs, the network provides disaster-related information to the terminal if the terminal supports disaster roaming.

[0232] Explains an example of TS 23.122 V18.7.0 S3.10 Minimization of service interruption.

[0233] MS may support Minimization of service interruption (MINT). For reference, in the disclosure of this specification, UE may include MS. Alternatively, UE and MS may be used as terms with the same meaning.

[0234] MINT is not applicable to SNPN.

[0235] In the case of a PLMN providing disaster roaming services, if one of the CAG-IDs broadcast by the CAG cell for the PLMN is authorized based on the "Allowed CAG List" included in the entry for the PLMN in the "CAG Information List," the UE may attempt to access the PLMN on the CAG cell for disaster roaming services.

[0236] If MS supports MINT, the network can provision to MS via the following:

[0237] a) An indication of whether disaster roaming is enabled in the UE is provided by the HPLMN;

[0238] b) A "list of PLMN(s) to be used in a disaster situation" provided by the HPLMN, containing zero or more entries, each entry containing a PLMN ID. The PLMNs are listed in order of highest priority, with the first PLMN being the highest priority PLMN;

[0239] c) One or more "lists of PLMN(s) to be used in a disaster situation," wherein each VPLMN may provide one "list of PLMN(s) to be used in a disaster situation." The "list of PLMN(s) to be used in a disaster situation" contains zero or more entries, and each entry contains a PLMN ID. The PLMNs are listed in order of decreasing priority, and the first PLMN is the highest priority PLMN;

[0240] d) Disaster roaming waiting range including minimum and maximum waiting times;

[0241] e) Disaster return waiting range including minimum and maximum waiting times; and

[0242] f) Indication of the 'applicability of the "list of PLMN(s) to be used in disaster situations" provided by the HPLN'.

[0243] During a successful registration process or a normal UE configuration update process, the network may provide the UE with a "list of PLMNs to be used in a disaster situation," a disaster roaming standby range, and a disaster return standby range. Additionally, during an unregistration process initiated by the network, a failed registration process, or a failed service request process, the network may provide the UE with a disaster return standby range. Additionally, during a UE parameter update process, the HPLMN may provide an indication of whether disaster roaming is enabled on the UE and an indication of the "applicability of the list of PLMNs to be used in a disaster situation" provided by the HPLMN.

[0244] Indications of whether disaster roaming is enabled in the UE, indications of the applicability of the “list of PLMN(s) to be used in disaster situations” provided by the VPLMN, one or more instances of the “list of PLMN(s) to be used in disaster situations” (each stored together with the PLMN identity of the PLMN that provided it), the disaster roaming standby range and disaster return standby range provisioned by the network are stored in the non-volatile memory of the ME. This is as specified in Appendix C of 3GPP TS 24.501.

[0245] Additionally, for the MS, an indication of whether disaster roaming is enabled in the UE, an indication of the applicability of the "list of PLMNs to be used in disaster situations" provided by the VPLMN, the "list of PLMNs to be used in disaster situations" provided by the HPLMN, and the disaster roaming standby range and disaster return standby range stored in the USIM may be pre-set for the MS (see 3GPP TS 31.102 V18.7.0).

[0246] 3GPP TS 24.501 Appendix C specifies the conditions under which the indication of whether disaster roaming is enabled on the UE, the indication of the 'applicability of the list of PLMNs to be used in disaster situations' provided by the VPLMN, one or more 'lists of PLMNs to be used in disaster situations', disaster roaming standby ranges, and disaster return standby ranges stored in the ME are deleted. Also:

[0247] a) When a USIM is inserted:

[0248] 1) In the following cases:

[0249] i) if the ME's non-volatile memory does not store an indication of whether disaster roaming is enabled in the UE; or

[0250] ii) If the SUPI from the USIM does not match the SUPI stored in the ME's non-volatile memory along with the indication of whether disaster roaming is enabled in the UE;

[0251] And if the MS stores an indication in the USIM whether disaster roaming is enabled in the UE (see 3GPP TS 31.102 V18.7.0), the MS stores the indication from the USIM regarding whether disaster roaming is enabled in the UE, along with the USIM's SUPI, in the ME's non-volatile memory. This is as specified in Annex C of 3GPP TS 24.501;

[0252] 2) In the following cases:

[0253] i) if the disaster roaming standby range is not stored in the ME's non-volatile memory; or

[0254] ii) If the USIM's SUPI does not match the SUPI stored in the ME's non-volatile memory along with the disaster roaming standby range;

[0255] And if the MS stores the disaster roaming standby range in the USIM (see 3GPP TS 31.102 V18.7.0), the MS stores the USIM's disaster roaming standby range together with the USIM's SUPI in the ME's non-volatile memory as specified in Appendix C of 3GPP TS 24.501;

[0256] 3) In the following cases:

[0257] i) if the disaster recovery standby range is not stored in the ME's non-volatile memory; or

[0258] ii) If the SUPI from the USIM does not match the SUPI stored in the ME's non-volatile memory along with the disaster recovery standby range;

[0259] And if the MS stores the disaster recovery standby range in the USIM (see 3GPP TS 31.102 V18.7.0), the MS stores the USIM's disaster recovery standby range together with the USIM's SUPI in the ME's non-volatile memory as specified in Appendix C of 3GPP TS 24.501

[0064] ;

[0260] 4) In the following cases:

[0261] i) where the indication of the 'applicability of the list of PLMN(s) to be used in disaster situations' provided by the VPLMN is stored in the ME's non-volatile memory; or

[0262] ii) If the USIM's SUPI does not match the SUPI stored in the ME's non-volatile memory along with an indication of the 'applicability of the "list of PLMNs to be used in disaster situations" provided by the VPLMN';

[0263] And if the MS holds an indication of the 'applicability of the list of PLMNs to be used in disaster situations' provided by the VPLMN stored in the USIM (see 3GPP TS 31.102 V18.7.0), the MS stores the indication of the 'applicability of the list of PLMNs to be used in disaster situations' provided by the USIM in the non-volatile memory of the ME together with the USIM's SUPI, as specified in Appendix C of 3GPP TS 24.501;

[0264] 5) In the following cases:

[0265] i) If the "list of PLMNs to be used in disaster situations" provided by HPLMN is not stored in the ME's non-volatile memory; or

[0266] ii) If the USIM's SUPI does not match the SUPI stored in the ME's non-volatile memory along with the "list of PLMNs to be used in disaster situations" provided by the HPLMN;

[0267] And if the MS stores the "list of PLMN(s) to be used in a disaster situation" provided by the HPLMN in the USIM, the MS stores the HPLMN's "list of PLMNs to be used in a disaster situation" provided in the USIM, together with the USIM's SUPI, in the non-volatile memory of the ME as specified in Appendix C of 3GPP TS 24.501;

[0268] b) When ME receives a USIM Application Toolkit (USAT) REFRESH command indicating the following:

[0269] 1) When the indication of whether the UE's disaster roaming is enabled, stored in the USIM, is updated, the MS stores the indication of whether the USIM's disaster roaming is enabled and the USIM's SUPI in the ME's non-volatile memory as specified in Appendix C of 3GPP TS 24.501;

[0270] 2) If the disaster roaming standby range stored in the USIM is updated, the MS stores the disaster roaming standby range of the USIM together with the USIM's SUPI in the non-volatile memory of the ME as specified in Appendix C of 3GPP TS 24.501;

[0271] 3) If the disaster recovery standby range stored in the USIM is updated, the MS must store the USIM's disaster recovery standby range together with the USIM's SUPI in the ME's non-volatile memory, as specified in Appendix C of 3GPP TS 24.501;

[0272] 4) If the indication of 'applicability of the list of PLMNs to be used in disaster situations provided by the VPLMN' stored in the USIM is updated, the MS shall store the indication of 'applicability of the list of PLMNs to be used in disaster situations' from the USIM in the non-volatile memory of the ME together with the USIM's SUPI, as specified in Appendix C of 3GPP TS 24.501; or

[0273] 5) If the "List of PLMNs to be used in disaster situations" provided by the HPLMN stored in the USIM is updated, the MS stores the "List of PLMNs to be used in disaster situations" provided by the HPLMN in the USIM, along with the USIM's SUPI, in the ME's non-volatile memory, as specified in Appendix C of 3GPP TS 24.501; or

[0274] NOTE 1: MS ignores the indication of whether the UE's disaster roaming is enabled stored in the USIM, except when the USIM is inserted or when the ME receives a USAT REFRESH command indicating that the indication of whether the UE's disaster roaming is enabled stored in the USIM has been updated.

[0275] NOTE 2: MS ignores the disaster roaming standby range stored in the USIM. However, exceptions apply when the USIM is inserted or when ME receives a USAT REFRESH command indicating that the disaster roaming standby range stored in the USIM has been updated.

[0276] NOTE 3: MS ignores the disaster recovery standby range stored in the USIM, except when the USIM is inserted or when ME receives a USAT REFRESH command indicating that the disaster recovery standby range stored in the USIM has been updated.

[0277] NOTE 4: MS ignores the 'applicability of the "list of PLMNs to be used in disaster conditions" provided by the VPLMN' stored in the USIM, except when the USIM is inserted or when the ME receives a USAT REFRESH command indicating that the 'applicability of the "list of PLMNs to be used in disaster conditions" provided by the VPLMN' stored in the USIM has been updated.

[0278] NOTE 5: MS ignores the "List of PLMNs to be used in disaster situations" provided by the HPLMN stored in the USIM, except when the USIM is inserted or when ME receives a USAT REFRESH command indicating that the "List of PLMNs to be used in disaster situations" provided by the HPLMN stored in the USIM has been updated.

[0279] If there is no indication of whether disaster roaming is enabled for the UE stored in the ME, or if the indication of whether disaster roaming is enabled for the UE stored in the ME is set to "Disaster roaming disabled on UE," disaster roaming is disabled on the MS. In this case, the MS must not perform disaster roaming.

[0280] After the ME selects a PLMN for disaster roaming, if a disaster roaming standby range is stored in the ME, the MS generates a random number within the disaster roaming standby range and starts a timer set to the generated random number. While the timer is running, the MS must not start registration except to perform an initial registration for emergency services on the selected PLMN. If an initial registration for emergency services is performed on the selected PLMN, the MS must continue running the timer. If the MS does not hold an emergency PDU session at the time the timer expires, the MS may start registration if it is still camp-on for the selected PLMN. If the MS holds an emergency PDU session at the time the timer expires, and the MS is still camp-on for the selected PLMN, the MS must release the emergency PDU session before starting registration.

[0281] The UE determines that the disaster state has ended if the following conditions are met:

[0282] a) If the UE is successfully registered with the PLMN via non-3GPP access;

[0283] b) If the UE is successfully registered with an acceptable PLMN;

[0284] c) where the UE is not registered for disaster roaming services, and the NG-RAN cell selected for camping the selected PLMN does not broadcast a disaster-related indication or a list of one or more PLMNs in a disaster state providing disaster roaming services provided by available PLMNs (including PLMNs determined by the MS in the disaster state); or

[0285] NOTE: If a UE is registered for disaster roaming services and the NG-RAN cell serving the registered PLMN does not broadcast all disaster-related indications or 'a list of one or more PLMNs in a disaster state for which available PLMNs provide disaster roaming services' (including PLMNs based on disaster conditions determined by MS), the UE does not determine that the disaster state has ended.

[0286] d) If a UE registered with the disaster roaming service receives cause value #11 "PLMN not allowed" or #13 "Roaming not allowed in this tracking area" during the registration procedure or service request procedure for a mobility registration update, or receives cause value #11 "PLMN not allowed" during the network start / unstart registration procedure.

[0287] If the ME confirms that the disaster condition has ended and the ME selects a PLMN that previously had a disaster condition, and the disaster return waiting range stored in the ME is provided by the following:

[0288] 1) PLMNs providing disaster roaming services; or

[0289] 2) Selected PLMN,

[0290] The MS must generate a random number within the disaster return waiting range and start a timer set to the generated random number. While the timer is running, the MS must not start registration except when performing an initial registration for emergency services on the selected PLMN. If an initial registration for emergency services is performed on the selected PLMN, the MS must continue running the timer. If the timer expires or has not started, and the MS is camping on the selected PLMN and there is no emergency PDU session, the MS may start registration. If the MS is camping on the selected PLMN and there is no emergency PDU session at the time the timer expires, the MS must continue camping on the selected PLMN and start registration after the emergency PDU session ends.

[0291] In the 23.122 spec, a procedure was studied in which, when a disaster occurs, the terminal performs PLMN selection using information received via broadcast from the NG-RAN, information received from the AMF, information stored in the USIM, etc.

[0292] According to prior art (e.g., 3GPP R17), a Minimization of Service Interruption (MINT) feature was developed to allow a terminal to receive services through another 5GS network when a disaster occurs and the terminal is unable to connect to the network it subscribed to. In addition, in 3GPP R19, a procedure study is being conducted to provide disaster roaming to UEs through EPS.

[0293] For the MINT feature, the Network may provide the UE with information regarding a Disaster Roaming Service, including at least one of a list of PLMNs to be used in the event of a Disaster, a Disaster Roaming Wait Range, and / or a Disaster Return Wait Range. Additionally, the UE may also store information related to the Disaster Roaming Service through pre-configuration. Here, the PLMN list may be information regarding the list of PLMNs available when a Disaster occurs in a VPLMN and / or HPLMN. The Disaster Roaming Wait Range may be a range of time for Congestion Control when the UE accesses another available PLMN due to a Disaster. The Disaster Return Wait Range may be a range of time for Congestion Control for the PLMN to return to when the UE returns to the PLMN it was originally able to connect to after the Disaster ends (e.g., when connecting).

[0294] In the event of a disaster, the Network can inform UEs which PLMNs are available. Additionally, the Network can implement measures to prevent a large number of UEs from accessing PLMNs during the disaster. To facilitate this, the AMF can provide UEs with information about the disaster through Registration Accept and UE Configuration Update messages. Furthermore, once the disaster ends, the Network can prevent a surge in access to recovered PLMNs through Registration Reject, Service Reject, and Network Initiated Deregistration messages.

[0295] Additionally, for a UE to access the 5GS, the UE may set one or more Access identities. Among them, a UE that intends to use Disaster roaming due to a Disaster may set its Access identity to 3. A UE for a Mission critical service may also set its Access identity to 2. A UE for a Priority service for Multimedia may also set its Access identity to 1. A UE using Disaster roaming may additionally set other Access identity values ​​in addition to Access identity 3. However, according to the prior art, in the case of Disaster roaming, the UE checks for barring using Access identity 3.

[0296] Currently, although processing methods as described above have been researched to provide Disaster roaming services to UEs in Disaster situations, conventional technology has the problem of not supporting processing for specific UEs. For example, UEs providing public services (e.g., fire departments, police stations, etc.) that require rapid processing in Disaster situations need to be processed with top priority, unlike general UEs.

[0297] However, according to the prior art, in a disaster situation where the network currently connected to a UE fails and the UE attempts to connect to another network, the network provides a disaster roaming wait range to the UE to prevent congestion. According to the prior art, the UE must store the disaster roaming wait range and wait for a randomly generated or configured amount of time before attempting to connect to the other network. In this case, if a disaster roaming wait range is set for congestion control, a problem arises in which even specific UEs requiring fast processing must wait for the duration of the disaster roaming wait time range before accessing the network.

[0298] The present disclosure describes a procedure for a Network and / or UE to process immediately without delay (e.g., a procedure for immediately processing a UE's access to a network), taking into account the characteristics of specific UEs that require rapid processing in a disaster situation. This enables the effective management of UEs in a disaster situation by supporting UEs that provide priority services for specific public institutions, such as fire departments and police stations, to quickly connect to other networks (e.g., access them).

[0299] 1. First example of the disclosure of this specification

[0300] The present disclosure describes an example of a method for classifying and processing UEs in a network to enable rapid access to other networks by specific UEs (e.g., Access identity(id) = 1, 2, 11–15) that require rapid processing in a disaster situation. Such specific UEs requiring rapid processing may be interpreted as at least one of, for example, a UE whose connection or registration to a network must be processed quickly, a UE whose connection or registration to a network must be processed faster than a general UE, a UE whose connection or registration to a network must be processed without delay, a Public Safety UE (e.g., UE for Public Safety services), a Mission Critical UE (e.g., UE for Mission Critical services), a High Priority UE, and / or an MPS UE (UE for MPS). This may be applied throughout the specification.

[0301] In some implementations, during the Registration procedure, the UE may send a Registration request message to the Network (e.g., AMF) containing Access ID(s) information set on the UE.

[0302] In some implementations, the Network (e.g., AMF) may classify UEs into Normal UEs with low priority and Specific UEs with high priority that require fast processing, based on the UE's Access ID(s) information. For example, the Network (e.g., AMF) can determine which of the two UEs a UE belongs to.

[0303] In some implementations, the Network (e.g., AMF) may classify a UE into Normal UE and Specific UE based on information stored in the UE's subscriber information, even without receiving Access ID(s) information from the UE. A Specific UE may be, for example, a terminal with a higher priority than a Normal UE.

[0304] In some implementations, the Network (e.g., AMF) may classify the UE by checking both the Access ID(s) information from the above-mentioned UE and the information stored in the subscriber information. For example, the Network (e.g., AMF) may classify the UE based on information (MPS priority, MCX priority) regarding whether the UE is a Multimedia Priority Service (MPS) subscribed UE or a Mission Critical Service (MCX) subscribed UE included in the subscriber information.

[0305] Alternatively, in some implementations, the Network (e.g., AMF) may classify UEs based on various subscription information, such as the terminal's Subscribed S-NSSAI and DNN information. To this end, new subscription information (e.g., Allowed Access ID(s)) may be defined and used.

[0306] In some implementations, the Network (e.g., AMF) may classify the UE based on the RRC establishment cause provided by the terminal. For example, if the terminal uses values ​​such as mps-PriorityAccess, mcs-PriorityAccess, highPirorityAccess, etc. for the RRC establishment cause, the Network (e.g., AMF) may classify the terminal as a Specific UE (e.g., a terminal with high priority).

[0307] After the Network (e.g., AMF) classifies the UE, the Network may send the list of available PLMNs and the Disaster roaming wait range to the Normal UE and / or the Specific UE. For example, the Network (e.g., AMF) may send the list of available PLMNs and the Disaster roaming wait range to the Normal UE, and the Network (e.g., AMF) may send the list of available PLMNs and the Disaster roaming wait range to the Specific UE.

[0308] In some implementations, the Network (e.g., AMF) may additionally send an indication (or information) to the Specific UE to ignore the Disaster roaming wait range value (e.g., Disaster roaming wait range ignore indication (or information)). In some implementations, the Network may additionally send an indication (or information) to the Specific UE to ignore the Disaster return wait range value.

[0309] In some implementations, based on the Access ID, local policy / configuration, etc. of the Specific UE, the Network (e.g., AMF) may send information to the Specific UE regarding ignoring both the Disaster roaming wait range and the Disaster return wait range, or may send information to the Specific UE regarding ignoring only one of them.

[0310] One or more UEs can store one or more pieces of information received from the Network during the Registration procedure.

[0311] In the event of a Disaster, if another Access ID value is set along with Access ID 3, each UE can use the other Access ID value along with Access ID 3.

[0312] In some implementations, a Specific UE may receive an indication (or information) to ignore the Disaster roaming wait range. In this case, the Specific UE can locate a PLMN in the list of available PLMNs and immediately send a Registration request. On the other hand, a Normal UE can wait for the Disaster roaming wait range to prevent congestion before sending a Registration request from an available PLMN.

[0313] In some implementations, the Network (e.g., AMF) can set the Disaster roaming wait range value of the Specific UE and / or General UE to 0. For example, the Network (e.g., AMF) can set both the Minimum registration wait time and the Maximum registration wait time to 0. In this case, the timers of the Specific UE and / or General UE will not start during a disaster (i.e., without generating a random number on the range), and the Specific UE and / or General UE can immediately register with the PLMN.

[0314] The embodiment of FIG. 7 below shows the overall flow in which a Network classifies a specific UE and performs processing related to the specific UE. Although the present disclosure describes the procedure based on the 5GS, this is merely an example. The scope of the present disclosure is not limited to the 5GS, and various examples of the present disclosure may be extended and applied to the procedures of future mobile communication systems such as the 6GS.

[0315] The following drawings are made to illustrate a specific example of the present specification. The names of specific devices or specific signals / messages / fields described in the drawings are presented as examples, and therefore the technical features of the present specification are not limited to the specific names used in the following drawings.

[0316] FIG. 7 illustrates an example of a procedure according to the first example of the present disclosure.

[0317] In the example of FIG. 7, the first UE, the second UE, network-D, and network-A are shown.

[0318] Network-D may be, for example, a network where a disaster has occurred or a network where a disaster is to occur. Additionally, if the disaster situation of Network-D ends, Network-D may become a general network that the UE will use upon return after the disaster situation ends. Network-A may be a network that provides disaster roaming services during a disaster situation.

[0319] For reference, in the examples of FIG. 7 and FIG. 8, the first UE may be a normal UE. The second UE may be a specific UE. For example, the specific UE may be a UE with a higher priority than the normal UE.

[0320] In step (S701), the first UE can send a registration request message to network-D.

[0321] In step (S702), the second UE can send a registration request message to network-D.

[0322] In step (S703), Network-D can classify the UE.

[0323] In step (S704), Network-D may send a response message to the first UE. For example, the response message may be a registration acceptance message or a configuration update command message.

[0324] The response message may include a disaster roaming standby range and / or a PLMN list. For example, the PLMN list may be a list of PLMNs to be used in a disaster situation.

[0325] In step (S705), Network-D may send a response message to the second UE. For example, the response message may be a registration acceptance message or a configuration update command message.

[0326] The response message may include a disaster roaming wait range and / or a list of PLMNs. For example, the list of PLMNs may be a list of PLMNs to be used in a disaster situation. The response message sent to the second UE may further include a disaster roaming wait range ignore indication (or information).

[0327] In step (S706), a disaster may occur in Network-D.

[0328] In step (S707), the second UE may send a registration request message to Network-A. The second UE may send the registration request message without performing a disaster roaming wait based on a disaster roaming wait range ignore indication (or information).

[0329] In step (S708), the first UE may perform disaster roaming wait. For example, the first UE may start a timer based on the disaster roaming wait range and not send a registration request message until the timer expires.

[0330] In step (S709), the first UE can send a registration request message to Network-A.

[0331] In some implementations, Network-D can classify UEs based on Access identities and / or subscription information received from UEs via a Registration request. For example, in the example in Table 3, the Network may receive Access identity number 3 along with one or more of Access identity numbers 1, 2, 11 through 15 from a UE. In this case, the Network may classify this UE as a Specific UE requiring rapid processing in a Disaster situation. As another example, if only Access identity number 3 is set for a UE, the Network may classify this UE as a Normal UE.

[0332] For reference, in the first example of the disclosure of this specification, Network-D may be a Network function such as AMF.

[0333] With respect to the TS24.501 V18.8.0 S4.24 Minimization of service interruption described above, the following modifications based on the first example disclosed in this specification may be applied.

[0334] If the AMF determines that the UE access identity is 1, 2, or 11–15 and 3 (e.g., if the UE access identity is determined to be 1, 2, or one or more of 11–15 and 3), the AMF may include a disaster roaming standby range ignore indication IE in the REGISTRATION ACCEPT message or the UE CONFIGURATION UPDATE COMMAND message.

[0335] Additionally, modifications based on the first example of the disclosure of this specification may be applied to the Registration wait range of TS24.501 V18.8.0 S9.11.3.84. For example, a Registration wait range ignore indication (RWRI) may be added to the examples in Table 4 and Table 5. Tables with these modifications applied are shown in the following Tables 6 and 7.

[0336] The purpose of the registration standby range information element is to provide the UE with a disaster roaming standby range and / or a disaster return standby range.

[0337] The registration waiting range information element is coded as shown in Tables 5 and 6.

[0338] The registration waiting range is a type 4 information element of 5 octets in length.

[0339] 87654321 Registration wait range IEI Octet 1 Length of registration wait range Octet 2 Minimum registration wait time Octet 3 Maximum registration wait time Octet 4 RWRI Octet 5

[0340] Table 6 is an example of a Registration wait range information element.

[0341] Minimum Registration Wait Time (octet 3) The minimum registration wait time includes the minimum duration of the registration wait time encoded in octet 2 of the GPRS timer information element (see 3GPP TS 24.008 Section 10.5.7.3). Maximum Registration Wait Time (octet 4) The maximum registration wait time includes the maximum duration of the registration wait time encoded in octet 2 of the GPRS timer information element (see 3GPP TS 24.008 Section 10.5.7.3). Registration wait range ignore indication (RWRI) (Bit 1 of Octet 5) Bit 10 No additional information 1 Registration wait range ignored

[0342] Table 7 is an example of a Registration wait range information element. The contents of Table 7 explain the minimum registration wait time, maximum registration wait time, and RWRI of Table 6.

[0343] 2. Second example of the disclosure of this specification

[0344] A second example of the disclosure of this specification describes an example of a method for a specific UE (e.g., a UE with one or more of Access id = 1, 2, 11 to 15) that requires rapid processing in a disaster situation to rapidly access another network. For example, a method is described in which a specific UE ignores the disaster roaming wait range and / or the disaster return wait range.

[0345] A specific UE requiring such rapid processing may be interpreted as at least one of, for example, a UE for which network access or registration must be processed quickly; a UE for which network access or registration must be processed quickly compared to a general UE; a UE for which network access or registration must be processed without delay; a Public Safety UE (e.g., UE for Public Safety services); a Mission Critical UE (e.g., UE for Mission Critical services); a High Priority UE; and / or an MPS UE (UE for MPS). This may be applied throughout this specification.

[0346] During the registration procedure, the Network (e.g., AMF) may transmit to the UE at least one of the available PLMN list and / or Disaster roaming wait range.

[0347] The UE can store information received from the Network during the Registration procedure. For the UE, at least one value among Access ID 1, 2, or 11–15 may be set along with Access ID 3. In this case, when a Disaster occurs, even if the UE stores the Disaster roaming wait range, if at least one value among Access ID 1, 2, or 11–15 is set along with Access ID 3 for the UE, the UE may ignore the Disaster roaming wait range, find an available PLMN, and immediately perform signaling such as a Registration request.

[0348] In addition, after the Disaster ends, if the UE's Access ID is set to 1 or 2 or 11~15 along with Access ID 3, the UE can ignore the Disaster return wait range even if it has stored the Disaster return wait range and immediately perform signaling, such as a Registration request, to the PLMN that was originally connected.

[0349] The following example illustrates the overall flow in which a specific UE in this disclosure performs processing while ignoring the stored Disaster roaming wait range and Disaster return wait range during a Disaster situation. Although this disclosure describes the procedure based on the 5GS, it can be extended and applied to the procedure of future mobile communication systems such as the 6GS rather than being limited to the 5GS.

[0350] The embodiment of FIG. 8 below illustrates the overall flow in which a specific UE in the present disclosure performs processing while ignoring the stored Disaster roaming wait range and / or Disaster return wait range in a Disaster situation. Although the present disclosure describes the procedure based on the 5GS, this is merely an example. The scope of the present disclosure is not limited to the 5GS, and various examples of the present disclosure may be extended and applied to the procedures of future mobile communication systems such as the 6GS.

[0351] The following drawings are made to illustrate a specific example of the present specification. The names of specific devices or specific signals / messages / fields described in the drawings are presented as examples, and therefore the technical features of the present specification are not limited to the specific names used in the following drawings.

[0352] FIG. 8 illustrates an example of a procedure according to the second example of the present disclosure.

[0353] In the example of FIG. 7, the first UE, the second UE, network-D, and network-A are shown.

[0354] Network-D may be, for example, a network where a disaster has occurred or a network where a disaster is to occur. Additionally, if the disaster situation of Network-D ends, Network-D may become a general network that the UE will use upon return after the disaster situation ends. Network-A may be a network that provides disaster roaming services during a disaster situation.

[0355] For reference, in the examples of FIG. 7 and FIG. 8, the first UE may be a normal UE. The second UE may be a specific UE. For example, the specific UE may be a UE with a higher priority than the normal UE.

[0356] In step (S801), the first UE can send a registration request message to network-D.

[0357] In step (S802), the second UE can send a registration request message to network-D.

[0358] In step (S803), Network-D may send a response message to the first UE. For example, the response message may be a registration acceptance message or a configuration update command message.

[0359] The response message may include a disaster roaming standby range and / or a PLMN list. For example, the PLMN list may be a list of PLMNs to be used in a disaster situation.

[0360] In step (S804), Network-D may send a response message to the second UE. For example, the response message may be a registration acceptance message or a configuration update command message.

[0361] The response message may include a disaster roaming standby range and / or a PLMN list. For example, the PLMN list may be a list of PLMNs to be used in a disaster situation.

[0362] In step (S805), a disaster may occur in Network-D.

[0363] In step (S806), the second UE may ignore the disaster roaming wait range. For example, the second UE may not start a timer based on the disaster roaming wait range stored in the second UE.

[0364] In some implementations, for the second UE, Access ID 3 may be set with one or more of Access identity 1 or 2 or 11 through 15. In this case, the second UE may ignore the disaster roaming standby range.

[0365] In some implementations, one or more of access identities 1, 2, 12, 13, or 14 are set on the second UE, and the set access identity may be valid in the selected PLMN. The second UE may select a PLMN for disaster roaming. In this case, based on the fact that one or more of access identities 1, 2, 12, 13, or 14 are set on the second UE and the set access identity is valid in the selected PLMN, the UE may perform a registration procedure for disaster roaming services in the selected PLMN. For example, the UE may send a registration request message to Network-A in step (S807).

[0366] In step (S807), the second UE can send a registration request message to network-A.

[0367] In step (S808), the first UE may perform disaster roaming wait. For example, the first UE may start a timer based on the disaster roaming wait range and not send a registration request message until the timer expires. For example, the first UE may generate a random number within the disaster roaming wait range and start a timer based on the generated random number.

[0368] In step (S809), the first UE can send a registration request message to network-A.

[0369] In step (S810), the disaster can be terminated.

[0370] In step (S811), the second UE can ignore the disaster return waiting range.

[0371] For reference, the second UE may receive a disaster standby return range included in at least one response message among a registration acceptance message, a service acceptance message, and / or a UE setting acceptance message. Alternatively, a disaster standby range may be pre-configured in the terminal.

[0372] In step (S812), the second UE can select PLMN.

[0373] In some implementations, also, if Access ID 3 is set on the second UE along with one or more of Access identities (ID) 1 or 2 or 11 through 15 after the Disaster ends, the second UE may ignore the Disaster return wait range even if it has stored the Disaster return wait range. The second UE may immediately perform signaling, such as a Registration request, to the PLMN it originally connected to.

[0374] In some implementations, the second UE may determine that the disaster condition has ended. The UE may stop the timer if it is running based on a random number generated within the disaster roaming wait range. The UE may select a PLMN. If the second UE has a disaster return wait range and the UE selects a PLMN, i) access identity 1, 2, 11, 12, 13, 14, or 15 is set on the UE and the access identity is invalid in the selected PLMN; or ii) access identity 1, 2, 11, 12, 13, 14, or 15 is not set on the second UE, the UE may generate a random number within the disaster return wait range and start a timer based on the generated random number. Otherwise, the UE may perform a registration procedure within the selected PLMN. For example, if one or more of access identities 1, 2, 12, 13, 14, or 15 are set on the second UE and the set access identity is valid, the second UE can perform a registration procedure within the selected PLMN. In this case, the second UE can ignore the disaster return waiting range.

[0375] With respect to the TS24.501 V18.8.0 S4.24 Minimization of service interruption described above, the following modifications based on the second example disclosed in this specification may be applied. A MINT (Minimization of service interruption) to which the content based on the second example disclosed in this specification is applied is described.

[0376] The UE and the network can support Minimization of service interruption (MINT). MINT aims to enable the UE to obtain services from a PLMN that provides disaster roaming services to a UE-determined PLMN based on disaster conditions.

[0377] If the UE supports MINT, the indication of whether disaster roaming is enabled within the UE, the indication of the applicability of the "list of PLMNs to be used in disaster conditions" provided by the VPLMN, one or more "lists of PLMN(s) to be used in disaster conditions," the disaster roaming wait range and disaster return wait range provided by the network (if available) are stored in the non-volatile memory of the ME as specified in Appendix C of TS24.501 V18.8.0 and are retained when the UE enters the 5GMM-DEREGISTERED state. Appendix C of TS24.501 V18.8.0 specifies the conditions under which the indication of whether disaster roaming is enabled within the UE, the indication of the "applicability of the list of PLMN(s) to be used in disaster conditions" provided by the VPLMN, one or more "lists of PLMNs to be used in disaster conditions" stored in the ME, the disaster roaming wait range and the disaster return wait range are deleted.

[0378] When a UE selects a PLMN for disaster roaming as specified in 3GPP TS 23.122 V18.7.0:

[0379] a) If there is no disaster roaming standby range stored in the UE, the UE performs the registration procedure for disaster roaming services in the selected PLMN as described in Section 5.5.1 of TS24.501 V18.8.0; and

[0380] b) If the UE has a stored disaster roaming wait range, the UE generates a random number within the disaster roaming wait range and starts a timer with the generated random number. If the UE is set to Access Identity 3 and Access Identity 1, 2, 11, 12, 13, 14, or 15, the UE ignores the disaster roaming wait range and starts registration with the selected PLMN. While the timer is running, the UE does not start registration with the selected PLMN, except when the UE needs to request an emergency Protocol Data Unit (PDU) (or Packet Data Unit) session; in this case, the UE must start the registration procedure, set the 5GS registration type IE to "Emergency Registration" in the REGISTRATION REQUEST message, and continue running the timer. When the timer expires, if the UE does not have an emergency PDU session and the UE is still camped on the selected PLMN, the UE must perform the registration procedure for the disaster roaming service described in Section 5.5.1 of TS24.501 V18.8.0. When the timer expires, if the UE has an emergency PDU session and the UE remains camped on the selected PLMN, the UE must release the emergency PDU session and then perform the registration procedure for the disaster roaming service described in Section 5.5.1 of TS24.501 V18.8.0.

[0381] Content based on the second example of the disclosure of this specification may also be applied to 3GPP TS 38.331 S 5.3.14.5 Access barring check.

[0382] The UE can perform the following actions:

[0383] 1> One or more access identities 1, 2, 11, 12, 13, 14, or 15 are displayed, and

[0384] 2> If the corresponding bit of uac-BarringForAccessIdentity included in the "UAC barring parameter" is set to 0 for at least one of these access identities. For reference, uac-BarringForAccessIdentity indicates whether an access attempt is allowed for each access identity:

[0385] 3> The UE considers the access attempt to be allowed;

[0386] 2> Otherwise (else):

[0387] 3> If the access identity is also the same as 3:

[0388] 4> The UE considers the access attempt to be allowed;

[0389] 1> Otherwise (else):

[0390] 2> Where the establishment of an RRC connection is the result of the release of a redirect using mpsPriorityIndication (in NR or E-UTRAN). For reference, mpsPriorityIndication indicates that mps-PriorityAccess specifies the cause for connection establishment that a UE can establish for a new connection after redirection to NR, or specifies mps-PriorityAccess as the cause for resumption that can be set for resumption after redirection to NR; and

[0391] 2> If the bit corresponding to Access Identity 1 in uac-BarringForAccessIdentity included in the "UAC barring parameter" is set to 0:

[0392] 3> The UE considers the access attempt to be allowed;

[0393] 2> Otherwise, if Access Identity 3 is displayed:

[0394] 3> UE generates a uniformly distributed random number 'rand' in the range 0 ≤ rand < 1;

[0395] 3> If 'rand' is lower than the value indicated by uac-BarringFactorForAI3 included in the "UAC barring parameter". Note that uac-BarringFactorForAI3 is a barring factor applicable to Access Identity 3.

[0396] 4> The UE considers the access attempt to be allowed;

[0397] 3> Otherwise:

[0398] 4> The UE considers the access attempt to be barred;

[0399] 2> Otherwise:

[0400] 3> UE generates a uniformly distributed random number 'rand' in the range 0 ≤ rand < 1;

[0401] 3> If 'rand' is lower than the value indicated by uac-BarringFactorForAI3 included in the "UAC barring parameter":

[0402] 4> The UE considers the access attempt to be allowed;

[0403] 3> Otherwise:

[0404] 4> The UE considers the access attempt to be blocked;

[0405] 1> If the access attempt is deemed blocked:

[0406] 2> UE generates a uniformly distributed random number 'rand' in the range 0 ≤ rand < 1;

[0407] 2> Start timer T390 for the access category with a timer value calculated as follows using uac-BarringTime included in the "UAC barring parameter": T390 = (0.7+ 0.6*rand)*uac-BarringTime.

[0408] In some implementations, to facilitate rapid processing of specific UEs used by government agencies such as police stations and fire departments in disaster situations, a first network entity (e.g., AMF) classifies specific UEs and general UEs based on subscription information received from the UE.

[0409] In some implementations, a first network entity (e.g., AMF) may send a Disaster roaming wait range ignore indication to a specific UE for faster processing of a classified UE. Accordingly, in a disaster situation, the specific UE can immediately perform the registration procedure for the selected PLMN without waiting.

[0410] In some implementations, even if the UE receives and stores information about the disaster (PLMN list, disaster roaming wait range, etc.) from the AMF, if the UE’s Access identity includes 3 and also includes at least one of Access identities 1, 2, or 11 to 15, the UE can ignore the disaster roaming wait range value and perform the registration procedure in the selected PLMN.

[0411] A UE may select a PLMN for disaster roaming. 3GPP TS 23.122 V18.7.0 may be referenced regarding the selection of a PLMN for disaster roaming. If a UE selects a PLMN for disaster roaming, the following may apply:

[0412] a) If:

[0413] 1) If the UE does not have a saved disaster roaming standby range; or

[0414] 2) If access identity 1, 2, 12, 13, or 14 is set for the UE, and the set access identity is valid in the selected PLMN,

[0415] The UE performs the registration procedure for disaster roaming services in the selected PLMN as described in Section 5.5.1 of 3GPP TS 24.501. For example, the UE may transmit a registration request message; and

[0416] b) if the UE has a stored disaster roaming standby range; and

[0417] 1) If access identity 1, 2, 12, 13, or 14 is set for the UE and the set access identity is not valid in the selected PLMN; or

[0418] 2) If the access identity for the UE is not set to 1, 2, 12, 13, or 14,

[0419] The UE generates a random number within the disaster roaming standby range and starts a timer based on the generated random number. While the timer is running, the UE must not initiate the registration procedure for the selected PLMN. However, if the UE needs to request an emergency PDU session, it must initiate the registration procedure, set the 5GS registration type IE to "Emergency Registration" in the REGISTRATION REQUEST message, and continue running the timer. When the timer expires, if the UE does not hold an emergency PDU session and the UE is still camped on the selected PLMN, it performs the disaster roaming service registration procedure described in Section 5.5.1 of 3GPP TS 24.501. When the timer expires, if the UE holds an emergency PDU session and the UE is still camped on the selected PLMN, it releases the emergency PDU session and performs the disaster roaming service registration procedure described in Section 5.5.1 of 3GPP TS 24.501.

[0420] When the timer based on the disaster roaming standby range expires, the UE must not restart the timer based on the disaster roaming standby range value until the disaster state ends.

[0421] The UE may determine that the disaster condition has ended. For this, 3GPP TS 23.122 V18.7.0 may be referenced. If the UE determines that the disaster condition has ended, the following may apply:

[0422] a) If a timer started based on a random number generated within the disaster roaming standby range is running, the UE stops the timer;

[0423] b) The UE shall perform PLMN selection as specified in 3GPP TS 23.122 V18.7.0, except where the UE has already selected an acceptable PLMN as specified in 3GPP TS 23.122 V18.7.0; and

[0424] c) where the UE selects a PLMN related to the disaster condition (e.g., UE determined PLMN with disaster condition), and the UE has a PLMN providing disaster roaming services or a stored disaster return waiting range provided by the selected PLMN; and

[0425] 1) If access identity 1, 2, 12, 13, 14, or 15 is set for the UE and the set access identity is not valid in the selected PLMN; or

[0426] 2) If access identity 1, 2, 12, 13, 14, or 15 is not set for the UE,

[0427] The UE generates a random number within the disaster return waiting range and starts a timer based on the generated random number value. If the UE is registered, the UE enters the 5GMM-DEREGISTERED.ATTEMPTING-REGISTRATION state or the 5GMM-REGISTERED.ATTEMPTING-REGISTRATION-UPDATE state. While the timer is running, the UE must not initiate the registration procedure on the selected PLMN. An exception applies if the UE must request an emergency PDU session; in this case, the UE initiates the registration procedure, sets the 5GS registration type IE to "Emergency Registration" in the REGISTRATION REQUEST message, and continues running the timer. When the timer expires, if the UE does not hold an emergency PDU session and is still camped on the selected PLMN, the UE performs the registration procedure. If the UE holds an emergency PDU session at the timer expires and is still camped on the selected PLMN, the UE must release the emergency PDU session and perform the registration procedure described in Section 5.5.1 of 3GPP TS 24.501.

[0428] Otherwise, the UE performs the registration procedure at the selected PLMN. For example, the UE can send a registration request message at the selected PLMN.

[0429] The following drawings are made to illustrate a specific example of the present specification. The names of specific devices or specific signals / messages / fields described in the drawings are presented as examples, and therefore the technical features of the present specification are not limited to the specific names used in the following drawings.

[0430] FIG. 9 illustrates an example of operations according to one embodiment of the disclosure of the present specification.

[0431] For reference, the procedure illustrated in FIG. 9 is merely an example, and the scope of disclosure of this specification is not limited by the example of FIG. 9.

[0432] For example, regarding the example of FIG. 9, the operations described in the examples of FIG. 1 through 8 may also be applied. For example, even if the operations, contents, etc. are not directly described in the example of FIG. 9, the operations, contents, etc. described in various examples of the disclosure of this specification may be applied.

[0433] In the example of FIG. 9, the first network entity may be a network entity related to mobility (e.g., AMF). The first network entity may be an AMF of a PLMN selected by the UE in step (S901).

[0434] In step (S901), the UE can select a PLMN. For example, the UE can select a first PLMN for disaster roaming.

[0435] In step (S902), the UE can send a registration request message to the first network entity.

[0436] For example, the UE can send a first registration request message to a first network entity of a first PLMN selected for disaster roaming.

[0437] In some implementations, access identity 1, 2, 12, 13, or 14 is set in the UE, and based on the fact that the set access identity is valid in the first PLMN, the first registration request message may be transmitted.

[0438] In some implementations, even if the UE has a disaster roaming wait range, access identity 1, 2, 12, 13, or 14 is set on the UE, and based on the fact that the set access identity is valid in the selected first PLMN, the timer based on the disaster roaming wait range may not start.

[0439] In some implementations, the UE has a disaster roaming wait range, and based on the fact that the configured access identity is invalid in the selected first PLMN, the first registration request message may be transmitted after the timer based on the disaster roaming wait range has expired. For example, in this case, the UE may generate a random number within the disaster roaming wait range and start a timer based on the generated random number. After this timer has expired, the UE may transmit the first registration request message.

[0440] In some implementations, the UE may determine that the disaster condition has ended. Subsequently, the UE may select a second PLMN associated with the disaster condition. For example, the second PLMN associated with the disaster condition may be a PLMN to which the disaster condition applies (e.g., a PLMN where the disaster occurred). The UE may also send a second registration request message to a second network entity of said second PLMN.

[0441] In this case, in some implementations, the UE has a disaster roaming return range, and the access identity 1, 2, 12, 13, 14, or 15 is set on the UE, and the second registration request message may be transmitted based on the fact that the set access identity 1, 2, 12, 13, 14, or 15 is valid in the second PLMNN.

[0442] In some implementations, the second registration request message may be transmitted after a timer based on the disaster roaming return range has expired, based on i) the access identity 1, 2, 12, 13, 14, or 15 being set on the UE and the set access identity 1, 2, 12, 13, 14, or 15 being invalid, or ii) the access identity 1, 2, 12, 13, 14, or 15 not being set on the UE. In this case, for example, the UE may generate a random number within the disaster roaming return range and start a timer based on the generated random number. After this timer has expired, the UE may transmit the second registration request message to a second network entity of the second PLMN.

[0443] In the disclosure of this specification, a PLMN related to a disaster condition may be referred to, for example, as a PLMN with disaster condition or a UE-determined PLMN with disaster condition. A PLMN related to a disaster condition may be a PLMN to which a disaster condition applies.

[0444] This specification may have various effects.

[0445] For example, disaster roaming of the terminal can be effectively supported.

[0446] For example, even in a disaster situation, UEs belonging to specific public institutions (e.g., fire departments, police stations, etc.) can immediately perform the registration process without waiting time for network access. These UEs can receive communication services without delay. Consequently, they can use the voice / data services necessary for disaster response without interruption. By reducing unnecessary waiting time during the registration process for these UEs, emergency responsiveness can be improved.

[0447] The effects obtainable through the specific examples of this specification are not limited to those listed above. For example, there may be various technical effects that a person with ordinary skill in the related art can understand or derive 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.

[0448] For reference, the operation of the terminal (e.g., UE) described in this specification may be implemented by the device 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 an instruction / program (e.g., instruction, executable code) 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 (105 or 206) and execute the instruction / program 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.

[0449] Additionally, instructions for performing the operation 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). And, the instructions recorded in the storage medium may perform the operation of the terminal described in the disclosure of this specification by being executed by one or more processors (102 or 202).

[0450] For reference, the operation of a network node (e.g., Network-D, Network-A AMF, SMF, PCF, UDM, etc.) or a base station (e.g., NG-RAN, gNB, RAN, eNB, (R)AN, etc.) described in this specification may be implemented by the device of FIGS. 1 to 3, which will be described below. For example, the network node or base station may be the first device (100) or the second device (200) of FIG. 2. For example, the operation of a network node or base station described in this specification may be processed by one or more processors (102 or 202). The operation of a terminal described in this specification may be stored in one or more memories (104 or 204) in the form of an instruction / program (e.g., instruction, executable code) executable by one or more processors (102 or 202). One or more processors (102 or 202) can 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 the operation of a network node or base station as described in the disclosure of this specification.

[0451] Additionally, instructions for performing the operation of a network node or base station described in the disclosure of this specification may be stored in a non-volatile (or non-transient) computer-readable storage medium. The storage medium may be contained in one or more memories (104 or 204). And, the instructions recorded in the storage medium may perform the operation of a network node or base station described in the disclosure of this specification by being executed by one or more processors (102 or 202).

[0452] Although preferred embodiments have been described by way of example above, the disclosure of this specification is not limited to such specific embodiments, and may be modified, changed, or improved in various forms within the spirit of this specification and the categories described in the claims.

[0453] In the exemplary system described above, methods are described based on a flowchart as a series of steps or blocks, but are not limited to the order of the described steps, and some steps may occur in a different order or simultaneously with other steps as described above. Furthermore, a person skilled in the art will understand that the steps shown in the flowchart are not exclusive, and that other steps may be included, or that one or more steps of the flowchart may be omitted without affecting the scope of rights.

[0454] The claims described in this specification may be combined in various ways. For example, the technical features of the method claims in this specification may be combined to be implemented as a device, and the technical features of the device claims in this specification may be combined to be implemented as a method. Furthermore, the technical features of the method claims and the technical features of the device claims in this specification may be combined to be implemented as a device, and the technical features of the method claims and the technical features of the device claims in this specification may be combined to be implemented as a method. Other implementations are within the scope of the following claims.

Claims

A step in which User Equipment (UE) selects a first Public Land Mobile Network (PLMN) for disaster roaming; and The above UE includes the step of transmitting a first registration request message to a first network entity of the first PLMN, and A method in which an access identity 1, 2, 12, 13, or 14 is set in the UE, and a first registration request message is transmitted based on the fact that the set access identity is valid in the first PLMN. In paragraph 1, A method in which, even when the above UE has a disaster roaming wait range, access identity 1, 2, 12, 13, or 14 is set on the above UE, and based on the fact that the set access identity is valid in the selected first PLMN, a timer based on the disaster roaming wait range is not started. In paragraph 1 or 2, A method in which the first registration request message is transmitted after a timer based on the disaster roaming standby range expires, based on the fact that the above UE has a disaster roaming standby range and the above set access identity is not valid in the selected first PLMN. In any one of paragraphs 1 through 3, The stage of determining that disaster conditions have ended; A step of selecting a second PLMN related to the above disaster conditions; and A method further comprising the step of transmitting a second registration request message to a second network entity of the second PLMN. In any one of paragraphs 1 through 4, A method in which the above UE has a disaster roaming return range, the access identity 1, 2, 12, 13, 14, or 15 is set on the above UE, and the second registration request message is transmitted based on the fact that the set access identity 1, 2, 12, 13, 14, or 15 is valid in the second PLMNN. In any one of paragraphs 1 through 5, A method in which the second registration request message is transmitted after a timer based on the disaster roaming return range expires, based on the above UE having a disaster roaming return range, i) the access identity 1, 2, 12, 13, 14, or 15 is set on the above UE and the set access identity 1, 2, 12, 13, 14, or 15 is invalid, or ii) the access identity 1, 2, 12, 13, 14, or 15 is not set on the above UE. At least one transmitter / receiver; At least one processor; and It includes at least one memory that stores instructions and can be connected to operate with at least one processor, and The operation adapted to be performed by at least one processor is: a device which is a method according to any one of claims 1 to 6. At least one processor; and It includes at least one memory that stores instructions and is operablely electrically connected to at least one processor, and An operation performed based on the execution of the above instruction by the at least one processor is: a device which is a method according to any one of claims 1 to 6. As a non-transitory computer-readable medium (CRM) recording instructions, The above instructions, when executed by at least one processor, cause the at least one processor to perform: a method according to any one of claims 1 to 6. A first network entity of a first Public Land Mobile Network (PLMN) includes the step of receiving a first registration request message from User Equipment (UE), and The above-mentioned first PLMN is selected by the UE for disaster roaming, and A method in which an access identity 1, 2, 12, 13, or 14 is set in the UE, and a first registration request message is received based on the fact that the set access identity is valid in the first PLMN. In Paragraph 10, A method in which, even when the above UE has a disaster roaming wait range, access identity 1, 2, 12, 13, or 14 is set on the above UE, and based on the fact that the set access identity is valid in the selected first PLMN, a timer based on the disaster roaming wait range is not started. In Article 10 or Article 11, A method in which the first registration request message is received after a timer based on the disaster roaming standby range has expired, based on the fact that the above UE has a disaster roaming standby range and the above set access identity is not valid in the selected first PLMN. At least one transmitter / receiver; At least one processor; and It includes at least one memory that stores instructions and can be connected to operate with at least one processor, and The operation adapted to be performed by at least one processor is: a device which is a method according to any one of claims 10 to 12.

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