Method and apparatus to support service continuity at the end of a disaster scenario

Abstract

Methods and apparatuses are provided for supporting service continuity when a disaster situation ends. A user equipment (UE) receives a configuration update command message from a disaster roaming PLMN, the configuration update command message including information indicating that a disaster situation of a home PLMN (HPLMN) has ended. The UE waits until a service being received from the disaster roaming PLMN ends, and after the service being received from the disaster roaming PLMN ends, performs a procedure for deregistering from the disaster roaming PLMN based on the information indicating that the disaster situation of the HPLMN has ended.

Description

TECHNICAL FIELD

[0001] The disclosure relates to a method for supporting service continuity at the end of a disaster situation and a device for supporting the same. BACKGROUND

[0002] The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is a technology for allowing high-speed packet communications. Many schemes have been proposed for LTE objectives including those aiming to reduce user and provider costs, improve service quality, and expand and improve coverage and system capacity. As an upper layer requirement, 3GPP LTE needs to reduce costs per bit, increase service availability, use frequency bands flexibly, ensure a simple architecture, have open interfaces, and have appropriate power consumption of terminals.

[0003] The International Telecommunication Union (ITU) and 3GPP have started work on the requirements and specifications for New Radio (NR) systems. 3GPP must identify and develop the technology components needed to successfully standardize the new RAT that will meet the immediate market demand for wireless communication and the more long-term requirements set forth by the ITU Radio communication Sector (ITU-R) International Mobile Telecommunications (IMT)-2020 process. Further, NR should be able to use any spectrum band between 600 MHz and 100 GHz that is made available for wireless communication even in a more distant future. The NR should be able to use any spectrum band between 600 MHz and 100 GHz that is made available for wireless communication even in a more distant future.

[0004] The goal of NR is to develop a single technical framework addressing all usage scenarios, requirements and deployment scenarios including enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), ultra-reliable and low-latency communications (URLLC) etc. NR shall be inherently forward compatible.

[0005] Mobile communication services are becoming essential services in daily life, and communication carriers are making various attempts to prevent service interruption. For example, a communication carrier can install multiple wired networks (e.g., multiple wired networks between core network nodes) in a core network part, and can continuously provide a communication service using another wired network even if a problem occurs in one wired network. Alternatively, a communication carrier can install multiple core network nodes such as AMFs, so that even if a problem occurs in one core network node, other core network nodes perform backup to prevent a communication service from being disconnected.

[0006] However, the above countermeasures can be of no avail in the event of a disaster such as a fire or an earthquake. For example, in the event of a fire, all communication networks connected from one node of the wireless network to the outside can be lost. In addition, in a virtualized cloud environment, a plurality of core network nodes can be installed in one data center located in the same area. Therefore, if a fire or an earthquake occurs in the area where the data center is located, the functions of all core network nodes will be lost with high probability, regardless of how many core network nodes are installed. SUMMARY

[0007] TECHNICAL PROBLEM

[0008] When a communication service is not possible through a network of a specific operator due to a disaster, a method of minimizing service interruption by temporarily roaming users of the operator to a network of another operator in the vicinity is being discussed. In this case, if a UE receiving a disaster roaming service returns to the original network immediately after the disaster situation ends, a problem can occur in that the currently received service can suddenly stop.

[0009] TECHNICAL SOLUTION

[0010] In an aspect, a method performed by a user equipment (UE) operating in a wireless communication system is provided. The method includes the steps of receiving, from a disaster roaming PLMN, a configuration update command message including information indicating that a disaster situation of a home HPLMN (HPLMN) has ended; waiting until a service being received from the disaster roaming PLMN ends; after the service received from the disaster roaming PLMN ends, performing a procedure of deregistering from the disaster roaming PLMN based on the information indicating that the disaster situation of the HPLMN has ended.

[0011] In another aspect, a device implementing the above-described method is provided.

[0012] EFFECT OF THE INVENTION

[0013] The present disclosure can have various advantageous effects.

[0014] For example, when a disaster situation ends, a UE that has used disaster roaming from a disaster roaming communication network can return to an original communication network without interruption after normally ending an ongoing service, thereby improving a user experience of the UE.

[0015] The advantageous effects that can be obtained through specific embodiments of the present disclosure are not limited to the advantageous effects enumerated above. For example, there can be various technical effects that can be understood and / or inferred by those of ordinary skill in the related art from the present disclosure. Therefore, specific effects of the present disclosure are not limited to the effects explicitly described herein, but can include various effects that can be understood or inferred from the technical features of the present disclosure. Attached Figure Description

[0016] Figure 1 An example of a communication system that applies the implementation of this disclosure is shown.

[0017] Figure 2 An example of a wireless device that applies the implementation of this disclosure is shown.

[0018] Figure 3 An example of a wireless device that applies the implementation of this disclosure is shown.

[0019] Figure 4 An example of a UE that applies the implementation of this disclosure is shown.

[0020] Figure 5 An example of a 5G system architecture applying the implementation of this disclosure is shown.

[0021] Figure 6 An example of a UE configuration update process applying the implementation of this disclosure is shown.

[0022] Figure 7 The concept of MINT, which applies the implementation of this disclosure, is shown.

[0023] Figure 8 An example of a method executed by a UE that applies an implementation of this disclosure is shown.

[0024] Figure 9 An example of signaling operation according to a first implementation of this disclosure is shown.

[0025] Figure 10 An example of signaling operation according to a second implementation of this disclosure is shown. Detailed Implementation

[0026] The following techniques, apparatuses, and systems can be applied to various wireless multiple access systems. Examples of the multiple access systems include a code division multiple access (CDMA) system, a frequency division multiple access (FDMA) system, a time division multiple access (TDMA) system, an orthogonal frequency division multiple access (OFDMA) system, a single carrier frequency division multiple access (SC-FDMA) system, and a multicarrier frequency division multiple access (MC-FDMA) system. CDMA can be implemented by radio technology such as universal terrestrial radio access (UTRA) or CDMA2000. TDMA can be implemented by radio technology 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 by radio technology such as institute of electrical and electronics engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, or evolved UTRA (E-UTRA). UTRA is a part of universal mobile telecommunications system (UMTS). 3rd generation partnership project (3GPP) long term evolution (LTE) is a part of evolved UMTS (E-UMTS) using E-UTRA. 3GPP LTE employs OFDMA in DL and employs SC-FDMA in UL. Evolution of 3GPP LTE includes LTE-A (LTE-Advanced), LTE-A Pro, and / or 5G new radio (NR).

[0027] For ease of description, implementations of the disclosure are mainly described with respect to a 3GPP-based wireless communication system. However, technical features of the disclosure are not limited thereto. For example, although the following detailed description is given based on a mobile communication system corresponding to a 3GPP-based wireless communication system, aspects of the disclosure that are not limited to a 3GPP-based wireless communication system are applicable to other mobile communication systems.

[0028] For terms and technologies not specifically described among the terms and technologies employed in the disclosure, reference can be made to wireless communication standard documents published prior to the disclosure.

[0029] In the disclosure, "A or B" can mean "A only," "B only," or "both A and B." In other words, "A or B" can be interpreted as "A and / or B" in the disclosure. For example, "A, B, or C" can mean "A only," "B only," "C only," or "any combination of A, B, and C" in the disclosure.

[0030] In the disclosure, a slash ( / ) or a comma (,) can mean "and / or." For example, "A / B" can mean "A and / or B." Accordingly, "A / B" can mean "A only," "B only," or "both A and B." For example, "A, B, C" can mean "A, B, or C."

[0031] In the disclosure, "at least one of A and B" can mean "only A", "only B", or "both A and B". In addition, the expression "at least one of A or B" or "at least one of A and / or B" in the disclosure can be interpreted as the same as "at least one of A and B".

[0032] In addition, in the disclosure, "at least one of A, B, and C" can mean "only A", "only B", "only C", or "any combination of A, B, and C". In addition, "at least one of A, B, or C" or "at least one of A, B, and / or C" can mean "at least one of A, B, and C".

[0033] In addition, the parentheses used in the disclosure can mean "for example". In detail, when shown as "control information (PDCCH)", "PDCCH" can be proposed as an example of "control information". In other words, "control information" is not limited to "PDCCH" in the disclosure, and "PDDCH" can be proposed as an example of "control information". In addition, even when shown as "control information (i.e., PDCCH)", "PDCCH" can be proposed as an example of "control information".

[0034] The technical features described separately in one drawing in the disclosure can be implemented separately or simultaneously.

[0035] Although not limited thereto, various descriptions, functions, processes, suggestions, methods, and / or operation flowcharts of the disclosure disclosed herein can be applied to various fields requiring wireless communication and / or connection between devices (e.g., 5G).

[0036] Hereinafter, the disclosure will be described in greater detail with reference to the accompanying drawings. Unless otherwise specified, the same reference numbers in the following drawings and / or description can refer to the same and / or corresponding hardware blocks, software blocks, and / or functional blocks.

[0037] Figure 1 An example of a communication system to which implementations of the disclosure are applied is illustrated.

[0038] In Figure 1 The 5G use scenarios illustrated in the Figure 1 may be exemplary only, and the technical features of the disclosure can be applied to other 5G use scenarios not illustrated in the

[0039] Three major requirement categories of 5G include: (1) an enhanced mobile broadband (eMBB) category, (2) a massive machine type communications (mMTC) category, and (3) an ultra-reliable and low latency communications (URLLC) category.

[0040] Referring toFigure 1 The communication system 1 includes wireless devices 100a to 100f, a base station (BS) 200, and a network 300. Although Figure 1 A 5G network is exemplified as an example of the network of the communication system 1, but implementations of the disclosure are not limited to the 5G system, and can be applied to future communication systems other than the 5G system.

[0041] The BS 200 and the network 300 can be implemented as wireless devices, and a specific wireless device can operate as a BS / network node with respect to other wireless devices.

[0042] The wireless devices 100a to 100f represent devices that perform communication using a radio access technology (RAT) (e.g., 5G new RAT (NR) or LTE), and can be referred to as communication / wireless / 5G devices. The wireless devices 100a to 100f can include, but are not limited to, a robot 100a, vehicles 100b-1 and 100b-2, an extended reality (XR) device 100c, a handheld device 100d, a home appliance 100e, an IoT device 100f, and an artificial intelligence (AI) device / server 400. For example, the vehicles can include vehicles with wireless communication functionality, autonomous vehicles, and vehicles capable of performing communication between vehicles. The vehicles can include unmanned aerial vehicles (UAVs) (e.g., drones). The XR device can include an AR / VR / mixed reality (MR) device, and can be implemented in the form of a head-mounted device (HMD), a head-up display (HUD) mounted in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance device, a digital signage, a vehicle, a robot, etc. The handheld device can include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or smartglasses), and a computer (e.g., a notebook). The home appliance can include a TV, a refrigerator, and a washing machine. The IoT device can include a sensor and a smartmeter.

[0043] In the disclosure, the wireless devices 100a to 100f can be referred to as user equipment (UE). For example, the UE can include a cellular phone, a smartphone, a laptop computer, a digital broadcast terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation system, a slate personal computer (PC), a tablet PC, an ultrabook, a vehicle, a vehicle with an autonomous driving function, a connected car, a UAV, an AI module, a robot, an AR device, a VR device, an MR device, a hologram device, a public safety device, an MTC device, an IoT device, a medical device, a Fintech device (or a financial device), a security device, a weather / environment device, a device related to a 5G service, or a device related to a field of the fourth industrial revolution.

[0044] The UAV can be, for example, an aircraft that is piloted by a wireless control signal without a person being on board.

[0045] The VR device can include, for example, a device for implementing objects or backgrounds of a virtual world. The AR device can include, for example, a device implemented by connecting objects or backgrounds of a virtual world to objects or backgrounds of a real world. The MR device can include, for example, a device implemented by merging objects or backgrounds of a virtual world into objects or backgrounds of a real world. The hologram device can include, for example, a device for implementing a 360-degree stereoscopic image by recording and reproducing stereoscopic information using an interference phenomenon of light generated when two lasers called holography meet.

[0046] The public safety device can include, for example, an image relay device or an image device that can be worn on the body of a user.

[0047] The MTC device and the IoT device can be, for example, devices that do not need direct human intervention or manipulation. For example, the MTC device and the IoT device can include a smart meter, a vending machine, a thermometer, a smart light bulb, a door lock, or various sensors.

[0048] The medical device can be, for example, a device for the purpose of diagnosing, treating, alleviating, curing, or preventing a disease. For example, the medical device can be a device for the purpose of diagnosing, treating, alleviating, or correcting an injury or impairment. For example, the medical device can be a device for the purpose of inspecting, replacing, or modifying a structure or function. For example, the medical device can be a device for the purpose of adjusting pregnancy. For example, the medical device can include a device for treatment, a device for operation, a device for (in vitro) diagnosis, a hearing aid, or a device for surgery.

[0049] The safety device can be, for example, a device installed to prevent a danger that can occur and to maintain safety. For example, the safety device can be a camera, a closed-circuit TV (CCTV), a recorder, or a black box.

[0050] The Fintech device can be, for example, a device capable of providing a financial service such as mobile payment. For example, the Fintech device can include a payment device or a point of sale (POS) system.

[0051] The weather / environment device can include, for example, a device for monitoring or predicting weather / environment.

[0052] The wireless devices 100a-100f can be connected to the network 300 via the BS 200. The AI technology can be applied to the wireless devices 100a-100f, and the wireless devices 100a-100f can be connected to the AI server 400 via the network 300. The network 300 can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, and a super 5G network. Although the wireless devices 100a-100f can communicate with each other through the BS 200 / network 300, the wireless devices 100a-100f can perform direct communication (e.g., sidelink communication) with each other without going through the BS 200 / network 300. For example, the vehicles 100b-1 and 100b-2 can perform direct communication (e.g., vehicle-to-vehicle (V2V) / vehicle-to-everything (V2X) communication). The IoT devices (e.g., sensors) can perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100a-100f.

[0053] Wireless communication / connections 150a, 150b, and 150c can be established between the wireless devices 100a-100f and / or between the wireless devices 100a-100f and the BS 200 and / or between the BSs 200. In this document, the wireless communication / connections can be established through various RATs (e.g., 5G NR) such as uplink / downlink communication 150a, sidelink communication (or device-to-device (D2D) communication) 150b, inter-base station communication 150c (e.g., relay, integrated access and backhaul (IAB)), etc. The wireless devices 100a-100f and the BS 200 / wireless devices 100a-100f can transmit / receive radio signals to / from each other through the wireless communication / connections 150a, 150b, and 150c. For example, the wireless communication / connections 150a, 150b, and 150c can transmit / receive signals through various physical channels. To this end, at least a part of various configuration information configuration procedures, various signal processing procedures (e.g., channel encoding / decoding, modulation / demodulation, and resource mapping / demapping), and resource allocation procedures for transmitting / receiving radio signals can be performed based on various proposals of the disclosure.

[0054] AI refers to a field of studying artificial intelligence or a methodology that can create it, and machine learning refers to a field of defining various problems solved in the AI field and a field of a methodology of solving them. Machine learning is also defined as an algorithm that improves task performance through continuous experience of a task.

[0055] A robot means a machine that automatically processes or operates a given task by its own ability. In particular, a robot that has the ability to recognize an environment and make a self-determination to perform an action can be referred to as an intelligent robot. Robots can be classified into industrial, medical, home, military, etc. according to the purpose or the area of use. A robot can perform various physical operations such as moving a robot joint with an actuator or a motor. A movable robot further includes a wheel, a brake, a propeller, etc. on a driver, thereby allowing it to travel on the ground or fly in the air.

[0056] Autonomous driving means a technology of driving by itself, and an autonomous vehicle means a vehicle that drives without user control or with minimal user control. For example, autonomous driving can include keeping a lane while moving, automatically adjusting a speed such as adaptive cruise control, automatically driving along a set route, and automatically setting a route when a set destination. A vehicle covers a vehicle equipped with an internal combustion engine, a hybrid vehicle equipped with an internal combustion engine and an electric motor, and an electric vehicle equipped with an electric motor, and in addition to a car, can include a train, a motorcycle, etc. An autonomous vehicle can be seen as a robot having an autonomous driving function.

[0057] Extended reality is collectively referred to as VR, AR, and MR. VR technology provides objects and backgrounds of the real world only through a computer graphics (CG) image. AR technology provides a virtual CG image on a real object image. MR technology is a CG technology that combines virtual objects and combines them into the real world. MR technology is similar to AR technology in that they show real objects and virtual objects together. However, the difference is that in AR technology, virtual objects are used as a supplementary form of real objects, whereas in MR technology, virtual objects and real objects are used as equivalent personalities.

[0058] NR supports multiple numerologies (and / or multiple subcarrier spacings (SCSs)) to support various 5G services. For example, if the SCS is 15 kHz, wide areas can be supported in a legacy cellular band, and if the SCS is 30 kHz / 60 kHz, dense cities, lower latency, and wider carrier bandwidths can be supported. If the SCS is 60 kHz or more, a bandwidth greater than 24.25 GHz can be supported to overcome phase noise.

[0059] An NR frequency band can be defined as two types of frequency ranges, i.e., FR1 and FR2. The numerical values of the frequency ranges can change. For example, the two types of frequency ranges (FR1 and FR2) can be as shown in Table 1 below. For ease of explanation, among the frequency ranges used in the NR system, FR1 can mean a "range below 6 GHz," FR2 can mean a "range above 6 GHz," and can be referred to as a millimeter wave (mmW).

[0060] [Table 1]

[0061] Frequency Range Designation Corresponding Frequency Range Subcarrier Spacing FR1 450 MHz - 6000 MHz 15, 30, 60 kHz FR2 24250 MHz - 52600 MHz 60, 120, 240 kHz

[0062] As mentioned above, the numerical value of the frequency range of the NR system can change. For example, FR1 can include 410 MHz to 7125 MHz as shown in Table 2 below. That is, FR1 can include a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or above. For example, the frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or above included in FR1 can include an unlicensed band. The unlicensed band can be used for various purposes, for example, communication of a vehicle (for example, autonomous driving).

[0063] [Table 2]

[0064] Frequency Range Designation Corresponding Frequency Range Subcarrier Spacing FR1 410 MHz - 7125 MHz 15, 30, 60 kHz FR2 24250 MHz - 52600 MHz 60, 120, 240 kHz

[0065] Here, the radio communication technology implemented in the wireless device in the present disclosure can include a narrowband Internet of Things (NB-IoT) technology for low-power communication as well as LTE, NR, and 6G. For example, the NB-IoT technology can be an example of a low-power wide-area network (LPWAN) technology, can be implemented in a specification such as LTE Cat NB1 and / or LTE Cat NB2, and can not be limited to the above-mentioned name. Additionally and / or alternatively, the radio communication technology implemented in the wireless device in the present disclosure can communicate based on an LTE-M technology. For example, the LTE-M technology can be an example of a LPWAN technology, and be referred to as various names such as enhanced machine type communication (eMTC). For example, the LTE-M technology can be implemented in at least one of various specifications such as 1) LTE Cat 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-bandwidth limited (non-BL), 5) LTE-MTC, 6) LTE machine type communication, and / or 7) LTE M, and can not be limited to the above-mentioned name. Additionally and / or alternatively, the radio communication technology implemented in the wireless device in the present disclosure can include at least one of ZigBee, Bluetooth, and / or LPWAN considering low-power communication, and can not be limited to the above-mentioned name. For example, the ZigBee technology can generate a personal area network (PAN) associated with small / low-power digital communication based on various specifications such as IEEE 802.15.4, and can be referred to as various names.

[0066] Figure 2 An example of a wireless device to which implementations of the present disclosure is applied is illustrated.

[0067] Referring to Figure 2 , the first wireless device 100 and the second wireless device 200 can transmit / receive a radio signal to / from an external device through various RATs (e.g., LTE and NR).

[0068] In Figure 2 , {the first wireless device 100 and the second wireless device 200} can correspond to at least one of {the wireless devices 100a to 100f and the BS 200}, {the wireless devices 100a to 100f and the wireless devices 100a to 100f}, and / or {the BS 200 and the BS 200} in Figure 1

[0069] The first wireless device 100 can include at least one transceiver such as the transceiver 106, at least one processing chip such as the processing chip 101, and / or one or more antennas 108.

[0070] The processing chip 101 can include at least one processor such as the processor 102 and at least one memory such as the memory 104. In Figure 2 , the memory 104 is exemplarily shown as being included in the processing chip 101. Additionally and / or alternatively, the memory 104 can be placed outside of the processing chip 101.

[0071] The processor 102 can control the memory 104 and / or the transceiver 106, and can be adapted to implement the descriptions, functions, processes, proposals, methods, and / or operational flowcharts described in the present disclosure. For example, the processor 102 can process information within the memory 104 to generate first information / signal, and then transmit a radio signal including the first information / signal through the transceiver 106. The processor 102 can receive a radio signal including second information / signal through the transceiver 106, and then store information obtained by processing the second information / signal in the memory 104.

[0072] The memory 104 can be operatively connectable to the processor 102. The memory 104 can store various types of information and / or instructions. The memory 104 can store software code 105 that implements instructions that, when executed by the processor 102, perform the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the software code 105 can implement instructions that, when executed by the processor 102, perform the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the software code 105 can control the processor 102 to perform one or more protocols. For example, the software code 105 can control the processor 102 to perform one or more layers of a radio interface protocol.

[0073] ​Herein, the processor 102 and the memory 104 can be parts of a communication modem / circuit / chip designed to implement a RAT (e.g., LTE or NR). The transceiver 106 can be connected to the processor 102 and transmit and / or receive radio signals through one or more antennas 108. Each of the transceivers 106 can include a transmitter and / or a receiver. The transceiver 106 can be interchangeably used with a radio frequency (RF) unit. In the present disclosure, the first wireless device 100 can represent a communication modem / circuit / chip.

[0074] The second wireless device 200 can include at least one transceiver such as the transceiver 206, at least one processing chip such as the processing chip 201, and / or one or more antennas 208.

[0075] The processing chip 201 can include at least one processor such as the processor 202 and at least one memory such as the memory 204. In Figure 2 The memory 204 is exemplarily shown to be included in the processing chip 201. Additionally and / or alternatively, the memory 204 can be placed outside of the processing chip 201.

[0076] The processor 202 can control the memory 204 and / or the transceiver 206 and can be adapted to implement the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts described in the present disclosure. For example, the processor 202 can process information within the memory 204 to generate third information / signal and then transmit a radio signal including the third information / signal through the transceiver 206. The processor 202 can receive a radio signal including fourth information / signal through the transceiver 106 and then store information obtained by processing the fourth information / signal in the memory 204.

[0077] The memory 204 can be operatively connected to the processor 202. The memory 204 can store various types of information and / or instructions. The memory 204 can store software code 205 that implements instructions that, when executed by the processor 202, perform the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the software code 205 can implement instructions that, when executed by the processor 202, perform the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the software code 205 can control the processor 202 to perform one or more protocols. For example, the software code 205 can control the processor 202 to perform one or more layers of a radio interface protocol.

[0078] Herein, the processor 202 and the memory 204 can be part of a communication modem / circuitry / chip designed for implementing a RAT (e.g., LTE or NR). The transceiver 206 can be connected to the processor 202 and transmit and / or receive radio signals through one or more antennas 208. Each of the transceivers 206 can include a transmitter and / or a receiver. The transceiver 206 can be used interchangeably with an RF unit. In the present disclosure, the second wireless device 200 can represent a communication modem / circuitry / chip.

[0079] Hereinafter, the hardware elements of the wireless devices 100 and 200 will be described in more detail. One or more protocol layers can be implemented by, without being limited to, one or more processors 102 and 202. For example, the one or more processors 102 and 202 can implement one or more layers (e.g., functional layers such as a physical (PHY) layer, a medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, a radio resource control (RRC) layer, and a service data adaptation protocol (SDAP) layer). The one or more processors 102 and 202 can generate one or more protocol data units (PDUs) and / or one or more service data units (SDUs), according to the descriptions, functions, procedures, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure. The one or more processors 102 and 202 can generate messages, control information, data, or information, according to the descriptions, functions, procedures, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure. The one or more processors 102 and 202 can generate signals (e.g., baseband signals) including the PDUs, SDUs, messages, control information, data, or information, according to the descriptions, functions, procedures, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure, and provide the generated signals to the one or more transceivers 106 and 206. The one or more processors 102 and 202 can receive signals (e.g., baseband signals) from the one or more transceivers 106 and 206, and acquire the PDUs, SDUs, messages, control information, data, or information, according to the descriptions, functions, procedures, suggestions, methods, and / or operation flowcharts disclosed in the present disclosure.

[0080] The one or more processors 102 and 202 can be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The one or more processors 102 and 202 can be implemented by hardware, firmware, software, or a combination thereof. As an 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), or one or more field programmable gate arrays (FPGAs) can be included in the one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in the present disclosure can be implemented using firmware or software, and the firmware or software can be configured to include modules, processes, or functions. The firmware or software configured to perform the descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in the present disclosure can be included in the one or more processors 102 and 202, or stored in the one or more memories 104 and 204, so as to be driven by the one or more processors 102 and 202. The descriptions, functions, processes, proposals, methods, and / or operational flowcharts disclosed in the present disclosure can be implemented using firmware or software in the form of codes, commands, and / or command sets.

[0081] The one or more memories 104 and 204 can be connected to the one or more processors 102 and 202 and store various types of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories 104 and 204 can be configured by read-only memory (ROM), random access memory (RAM), electrically erasable programmable read-only memory (EPROM), flash memory, a hard disk drive, a register, a cache memory, a computer-readable storage medium, and / or a combination thereof. The one or more memories 104 and 204 can be located inside and / or outside the one or more processors 102 and 202. The one or more memories 104 and 204 can be connected to the one or more processors 102 and 202 by various techniques such as wired or wireless connections.

[0082] The one or more transceivers 106 and 206 can transmit user data, control information, and / or radio signals / channels mentioned in the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure to one or more other apparatuses. The one or more transceivers 106 and 206 can receive user data, control information, and / or radio signals / channels mentioned in the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure from one or more other apparatuses. For example, the one or more transceivers 106 and 206 can be connected to the one or more processors 102 and 202 and transmit and receive radio signals. For example, the one or more processors 102 and 202 can perform control so that the one or more transceivers 106 and 206 can transmit user data, control information, or radio signals to one or more other apparatuses. The one or more processors 102 and 202 can perform control so that the one or more transceivers 106 and 206 can receive user data, control information, or radio signals from one or more other apparatuses.

[0083] The one or more transceivers 106 and 206 can be connected to the one or more antennas 108 and 208, and the one or more transceivers 106 and 206 can be configured to transmit and receive user data, control information, and / or radio signals / channels mentioned in the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure through the one or more antennas 108 and 208. In the present disclosure, the one or more antennas 108 and 208 can be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports).

[0084] The one or more transceivers 106 and 206 can convert received user data, control information, radio signals / channels, and the like from RF band signals to baseband signals in order to process the received user data, control information, radio signals / channels, and the like using the one or more processors 102 and 202. The one or more transceivers 106 and 206 can convert user data, control information, radio signals / channels, and the like processed using the one or more processors 102 and 202 from baseband signals to RF band signals. To do so, the one or more transceivers 106 and 206 can include (analog) oscillators and / or filters. For example, the one or more transceivers 106 and 206 can up-convert OFDM baseband signals to OFDM signals in carrier frequencies through their (analog) oscillators and / or filters under the control of the one or more processors 102 and 202 and transmit the up-converted OFDM signals. The one or more transceivers 106 and 206 can receive OFDM signals of carrier frequencies and down-convert the OFDM signals to OFDM baseband signals through their (analog) oscillators and / or filters under the control of the one or more processors 102 and 202.

[0085] In implementations of the disclosure, the UE can operate as a transmitting apparatus in uplink (UL) and as a receiving apparatus in downlink (DL). In implementations of the disclosure, the BS can operate as a receiving apparatus in UL and as a transmitting apparatus in DL. Hereinafter, for convenience of description, it is mainly assumed that the first wireless device 100 functions as a UE and the second wireless device 200 functions as a BS. For example, the processor 102 connected to, installed on, or launched in the first wireless device 100 can be configured to perform a UE behavior according to implementations of the disclosure, or control the transceiver 106 to perform a UE behavior according to implementations of the disclosure. The processor 202 connected to, installed on, or launched in the second wireless device 200 can be configured to perform a BS behavior according to implementations of the disclosure, or control the transceiver 206 to perform a BS behavior according to implementations of the disclosure.

[0086] In the disclosure, the BS is also referred to as a Node B (NB), an eNode B (eNB), or a gNB.

[0087] Figure 3 An example of a wireless device to which implementations of the disclosure are applied is illustrated.

[0088] The wireless device can be implemented in various forms according to use cases / services (refer to Figure 1 ).

[0089] Refer toFigure 3 Wireless devices 100 and 200 can correspond to Figure 2 The wireless devices 100 and 200 can be configured from various elements, components, units / parts, and / or modules. For example, each of the wireless devices 100 and 200 may include a communication unit 110, a control unit 120, a memory unit 130, and an additional component 140. The communication unit 110 may include a communication circuit 112 and a transceiver 114. For example, the communication circuit 112 may include... Figure 2 One or more processors 102 and 202 and / or Figure 2 One or more memories 104 and 204. For example, transceiver 114 may include Figure 2 One or more transceivers 106 and 206 and / or Figure 2 One or more antennas 108 and 208. Control unit 120 is electrically connected to communication unit 110, memory unit 130, and add-on components 140, and controls the overall operation of each of wireless devices 100 and 200. For example, control unit 120 can control the electrical / mechanical operation of each of wireless devices 100 and 200 based on programs / code / commands / information stored in memory unit 130. Control unit 120 can transmit information stored in memory unit 130 to an external source (e.g., other communication devices) via communication unit 110 through a wireless / wired interface, or store information received from an external source (e.g., other communication devices) via wireless / wired interface in memory unit 130 via communication unit 110.

[0090] The add-on component 140 can be configured differently depending on the type of wireless devices 100 and 200. For example, the add-on component 140 may include at least one of a power supply unit / battery, an input / output (I / O) unit (e.g., an audio I / O port, a video I / O port), a drive unit, and a computing unit. Wireless devices 100 and 200 can be, but are not limited to, robots (…). Figure 1 100a), vehicles ( Figure 1 100b-1 and 100b-2), XR device ( Figure 1 100c), handheld device ( Figure 1 100d), home appliances ( Figure 1 100e), IoT devices ( Figure 1 100f), digital broadcasting terminals, holographic devices, public safety devices, MTC devices, medical devices, Fintech devices (or financial devices), security devices, climate / environment devices, AI servers / devices ( Figure 1 400), BSS ( Figure 1The wireless devices 100 and 200 can be implemented in the form of a mobile phone, a smartphone, a computer, a laptop, a tablet, a wearable device, a network node, etc. The wireless devices 100 and 200 can be used in a mobile or fixed location depending on the use case / service.

[0091] In Figure 3 , the entirety of various elements, components, units / portions, and / or modules in the wireless devices 100 and 200 can be connected to each other through wired interfaces, or at least a part thereof can be wirelessly connected through the communication unit 110. For example, in each of the wireless devices 100 and 200, the control unit 120 and the communication unit 110 can be connected through wired connection, and the control unit 120 and the first units (e.g., 130 and 140) can be wirelessly connected through the communication unit 110. Each element, component, unit / portion, and / or module within the wireless devices 100 and 200 can further include one or more elements. For example, the control unit 120 can be configured by a set of one or more processors. As an example, the control unit 120 can be configured by a set of communication control processor, application processor (AP), electronic control unit (ECU), graphic processing unit, and memory control processor. As another example, the memory unit 130 can be configured by RAM, dynamic RAM (DRAM), ROM, flash memory, volatile memory, non-volatile memory, and / or a combination thereof.

[0092] Figure 4 An example of a UE to which implementations of the present disclosure is applied is illustrated.

[0093] Referring to Figure 4 , the UE 100 can correspond to a first wireless device 100 of Figure 2 and / or a wireless device 100 or 200 of Figure 3 .

[0094] The UE 100 includes a processor 102, a memory 104, a transceiver 106, one or more antennas 108, a power management module 110, a battery 112, a display 114, a keypad 116, a subscriber identity module (SIM) card 118, a speaker 120, and a microphone 122.

[0095] The processor 102 can be configured to implement descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. The processor 102 can be configured to control one or more other components of the UE 100 to implement descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. Layers of the radio interface protocol can be implemented in the processor 102. The processor 102 can include an ASIC, other chipset, logic circuit, and / or data processing apparatus. The processor 102 can be an application processor. The processor 102 can include at least one of a digital signal processor (DSP), a central processing unit (CPU), a graphics processing unit (GPU), a modem (modulator and demodulator). Examples of the processor 102 can be seen in Snapdragon TM series processors manufactured by Qualcomm®, Exynos TM series processors manufactured by Samsung®, A series processors manufactured by Apple®, Helio TM series processors manufactured by Qualcomm®, Atom TM series processors manufactured by Intel® or corresponding next-generation processors.

[0096] The memory 104 is operatively coupled with the processor 102 and stores various information to operate the processor 102 when in operation. The memory 104 can include ROM, RAM, flash memory, memory card, storage medium and / or other storage devices. When embodiments are implemented in software, the techniques described herein can be implemented with modules (e.g., procedures, functions, and so on) that perform tasks as described in the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts disclosed in the present disclosure. The modules can be stored in the memory 104 and executed by the processor 102. The memory 104 can be implemented in the processor 102 or external to the processor 102 in which case it can be communicatively coupled to the processor 102 via various means as is known in the art.

[0097] The transceiver 106 is operatively coupled with the processor 102 and transmits and / or receives radio signals when in operation. The transceiver 106 includes a transmitter and a receiver. The transceiver 106 can include a baseband circuitry for processing radio frequency signals. The transceiver 106 controls the one or more antennas 108 to transmit and / or receive radio signals.

[0098] The power management module 110 manages power of the processor 102 and / or the transceiver 106. The battery 112 supplies power to the power management module 110.

[0099] The display 114 outputs results processed by the processor 102. The keyboard 116 receives input to be used by the processor 102. The keyboard 116 can be shown on the display 114.

[0100] The SIM card 118 is an integrated circuit intended to securely store the international mobile subscriber identity (IMSI) number and its related key, which are used to identify and authenticate subscribers on mobile telephony devices (such as mobile phones and computers). It is also possible to store contact information on many SIM cards.

[0101] The speaker 120 outputs sound-related results processed by the processor 102. The microphone 122 receives sound-related input to be used by the processor 102.

[0102] Figure 5 An example of a 5G system architecture to which implementations of the present disclosure are applied is shown.

[0103] The 5G system (5GS; 5G System) architecture consists of the following network functions (NFs).

[0104] -AUSF (Authentication Server Function)

[0105] -AMF (Access and Mobility Management Function)

[0106] -DN (Data Network), e.g. operator services, internet access or third party services

[0107] -UDSF (Unstructured Data Storage Function)

[0108] -NEF (Network Exposure Function)

[0109] -I-NEF (Intermediate NEF)

[0110] -NRF (Network Repository Function)

[0111] -NSSF (Network Slice Selection Function)

[0112] -PCF (Policy Control Function)

[0113] -SMF (Session Management Function)

[0114] -UDM (Unified Data Management)

[0115] -UDR (Unified Data Repository)

[0116] -UPF (User Plane Function)

[0117] -UCMF (UE Radio Capability Management Function)

[0118] -AF (Application Function)

[0119] - UE (User Equipment)

[0120] - (R)AN ((Radio) Access Network)

[0121] - 5G-EIR (5G Equipment Identity Register)

[0122] - NWDAF (Network Data Analytics Function)

[0123] - CHF (Charging Function)

[0124] In addition, the following network functions can be considered.

[0125] - N3IWF (Non-3GPP InterWorking Function)

[0126] - TNGF (Trusted Non-3GPP Gateway Function)

[0127] - W-AGF (Wired Access Gateway Function)

[0128] Figure 5 A 5G system architecture depicting a non-roaming case using reference point representation of how the various network functions interact with each other.

[0129] In Figure 5 , for clarity of the point-to-point diagram, UDSF, NEF and NRF are not depicted. However, all network functions depicted can interact with UDSF, UDR, NEF and NRF as needed.

[0130] For clarity, the connection between UDR and other NFs (e.g. PCF) is not depicted in Figure 5 . For clarity, the connection between NWDAF and other NFs (e.g. PCF) is not depicted in Figure 5

[0131] The 5G system architecture comprises the following reference points.

[0132] - N1 : Reference point between UE and AMF

[0133] - N2: Reference point between (R)AN and AMF.

[0134] - N3: Reference point between (R)AN and UPF

[0135] - N4: Reference point between SMF and UPF.

[0136] - N6: Reference point between UPF and data network

[0137] - N9: Reference point between two UPFs.

[0138] ​The following reference points represent interactions between NF services in the NFs.

[0139] - N5: Reference point between PCF and AF.

[0140] - N7: Reference point between SMF and PCF.

[0141] - N8: Reference point between UDM and AMF.

[0142] - N10: Reference point between UDM and SMF.

[0143] - N11: Reference point between AMF and SMF.

[0144] - N12: Reference point between AMF and AUSF.

[0145] - N13: Reference point between UDM and AUSF.

[0146] - N14: Reference point between two AMFs.

[0147] - N15: Reference point between PCF and AMF in case of non-roaming scenario and between PCF and AMF in visited network in case of roaming scenario.

[0148] - N16: Reference point between two SMFs (in case of roaming, between SMF in visited network and SMF in home network)

[0149] - N22: Reference point between AMF and NSSF.

[0150] In some cases, it can be necessary to associate two NFs with each other to serve a UE.

[0151] Hereinafter, a UE configuration update procedure will be described. It can be referred to S5.4.4 of 3GPP TS 24.501 V16.5.0 (2020-06). Through the UE configuration update procedure newly introduced in the 5G system, the network can update various parameters and / or configurations of the UE, or can trigger re-registration of the UE.

[0152] More specifically, the purpose of the UE configuration update procedure is as follows.

[0153] a) To allow the AMF to update the UE configuration of access and mobility management related parameters decided and provided by the AMF by providing new parameter information within the command; or

[0154] b) To request the UE to perform a registration procedure for mobility and periodic registration update to the network to update the access and mobility management related parameters decided and provided by the AMF.

[0155] The procedure is initiated by the network and can only be used when the UE has established a 5GMM context and the UE is in 5GMM-CONNECTED mode. The AMF can use the paging or notification procedure to initiate the UE configuration update procedure when the UE is in 5GMM-IDLE mode. To ensure that the parameters have been updated by the UE, the AMF can request an acknowledgement response.

[0156] This procedure is initiated by the network after a successful service request procedure invoked in response to a paging request from the network and before the release of the N1 NAS signaling connection to assign a new 5G globally unique temporary identifier (5G-GUTI) to the UE. If the service request procedure was triggered due to 5GSM downlink signaling pending, the procedure for assigning a new 5G-GUTI can be initiated by the network after the 5GSM downlink signaling is delivered.

[0157] The following parameters are supported by the UE configuration update procedure without the need to request the UE to perform a registration procedure for mobility and periodic registration update.

[0158] a) 5G-GUTI;

[0159] b) Tracking Area Identifier (TAI) list;

[0160] c) Service Area list;

[0161] d) Network identity and time zone information (network full name, network short name, local time zone, universal time and local time zone, network daylight saving time);

[0162] e) Local Area Data Network (LADN) information;

[0163] f) Rejected Network Slice Selection Assistance Information (NSSAI);

[0164] g) Operator-defined access category definition;

[0165] h) Short Message Service (SMS) indication;

[0166] i) Service gap time value;

[0167] j) Closed Access Group (CAG) information list;

[0168] k) UE radio capability ID;

[0169] l) 5GS registration result; and

[0170] m) Truncated 5G SAE Temporary Mobile Subscriber Identity (5G-S-TMSI) configuration.

[0171] The following parameters can be sent to the UE with or without a request to perform a registration procedure for mobility and periodic registration update.

[0172] a) Allowed NSSAI;

[0173] b) Configured NSSAI; or

[0174] c) Network slice subscription change indication.

[0175] The following parameters are sent to the UE with a request to perform a registration procedure for mobility and periodic registration update.

[0176] a) Mobile initiated connection only (MICO) indication; or

[0177] b) UE radio capability ID deletion indication.

[0178] The following parameters are sent only over 3GPP access.

[0179] a) LADN information;

[0180] b) MICO indication;

[0181] c) TAI list;

[0182] d) Service area list;

[0183] e) Service gap time value;

[0184] f) CAG information list;

[0185] g) UE radio capability ID;

[0186] h) UE radio capability ID deletion indication; and

[0187] i) Truncated 5G-S-TMSI configuration.

[0188] The following parameters are managed and sent per access type, i.e., independently over 3GPP access or non-3GPP access.

[0189] a) Allowed NSSAI; and

[0190] b) Rejected NSSAI (when NSSAI is rejected for the current registration area).

[0191] The following parameters are commonly managed and sent over 3GPP access or non-3GPP access.

[0192] a) 5G-GUTI;

[0193] b) Network identity and time zone information;

[0194] c) rejected NSSAI (when NSSAI is rejected for the current Public Land Mobile Network (PLMN) or for failed or revoked NSSAA);

[0195] d) configured NSSAI;

[0196] e) SMS indication;

[0197] f) 5GS registration result.

[0198] Figure 6 An example of a UE configuration update procedure applying implementations of the present disclosure is shown.

[0199] Referring to Figure 6 The UE configuration update procedure is initiated when the AMF sends a configuration update command message to the UE.

[0200] The AMF includes in the configuration update command message:

[0201] a) one or more of the following parameters: 5G-GUTI, TAI list, allowed NSSAI which can include mapped single NSSAI (S-NSSAI), LADN information, service area list, MICO indication, NSSAI of network identity and time zone information, configured NSSAI which can include mapped S-NSSAI, rejected NSSAI, network slice subscription change indication, operator-defined access class definition, SMS indication, service gap time value, CAG information list, UE radio capability ID, 5GS registration result, UE radio capability ID deletion indication, or truncated 5G-S-TMSI configuration;

[0202] b) a configuration update indication information element (IE) with the registration request bit set to "request registration"; or

[0203] c) a combination of both a) and b).

[0204] If an acknowledgement from the UE is requested, the AMF indicates "request acknowledgement" in the acknowledgement bit of the configuration update indication IE in the configuration update command message and starts timer T3555. An acknowledgement is requested for all parameters except when only network identity and time zone information is included.

[0205] To initiate parameter renegotiation between the UE and the network, the AMF indicates "request registration" in the registration request bit of the configuration update indication IE in the configuration update command message.

[0206] If the AMF reconfiguration with new allowed NSSAI information or supported S-NSSAI requires AMF relocation, the AMF indicates "Request Registration" in the Registration Request bit of the Configuration Update Indication IE and includes the Allowed NSSAI IE in the Configuration Update Command message.

[0207] If the AMF includes the newly configured NSSAI in the Configuration Update Command message and the newly configured NSSAI requires AMF relocation, the AMF indicates "Request Registration" in the Registration Request bit of the Configuration Update Indication IE in the Configuration Update Command message.

[0208] If the Configuration Update Command message is initiated due to changes to the allowed NSSAI only and these changes require the UE to initiate the registration procedure, but the AMF is not able to determine the allowed NSSAI for the UE, then the Configuration Update Command message indicates "Request Registration" in the Registration Request bit of the Configuration Update Indication IE and does not contain any other parameters.

[0209] If the network slice specific authentication and authorization (NSSAA) procedure for an S-NSSAI is:

[0210] a) successfully completed, the AMF includes the S-NSSAI in the allowed NSSAI; or

[0211] b) failed, the AMF includes the S-NSSAI in the rejected NSSAI for failed or revoked NSSAA with the rejection cause "S-NSSAI not available due to failed or revoked network slice specific authentication and authorization".

[0212] If an S-NSSAI in the currently allowed NSAAI for an access type is revoked authorization, the AMF performs the following steps.

[0213] a) provides the UE with a new allowed NSSAI excluding the S-NSSAI that is revoked authorization; and

[0214] b) provides a new rejected NSSAI for failed or revoked NSSAA including the S-NSSAI in the rejected NSSAI that is revoked authorization with the rejection cause "S-NSSAI not available due to failed or revoked network slice specific authentication and authorization".

[0215] The allowed NSSAI and the rejected NSSAI are included in the Configuration Update Command message to reflect the outcome of the procedure that went through NSSAA.

[0216] If the AMF includes the network slice indication IE in the configuration update command message with the network slice subscription change indication set to "change network slice subscription" and a change to the allowed NSSAI requires the UE to initiate the registration procedure, but the AMF is not able to determine the allowed NSSAI for the UE, then the configuration update command message additionally indicates "request registration" in the registration request bit of the configuration update indication IE and does not include the allowed NSSAI.

[0217] If the AMF needs to update the LADN information, the AMF includes the LADN information IE in the configuration update command message.

[0218] If the AMF needs to update the CAG information list, the AMF includes the CAG information list IE in the configuration update command message. If the AMF needs to update the CAG information list and:

[0219] a) the UE has an emergency PDU session; and

[0220] b-1) the UE is in a CAG cell and none of the GAG-IDs supported by the CAG cell are included in the allowed CAG list for the current PLMN in the updated CAG information list; or

[0221] b-2) the UE is out of a CAG cell and the entry for the current PLMN in the updated CAG information list includes an indication that only allows the UE to access the 5GS via a CAG cell;

[0222] The AMF indicates to the SMF to perform local release of all non-emergency PDU sessions associated with 3GPP access.

[0223] If the AMF needs to update the truncated 5G-S-TMSI configuration for the UE in NB-N1 mode using control plane Cellular IoT (CIoT) 5GS optimization, the AMF includes the truncated 5G-S-TMSI configuration IE in the configuration update command message.

[0224] The network can send one or more configuration update command messages to the UE during an established 5GMM context. If more than one configuration update command message is sent, the messages do not need to have the same content.

[0225] Upon receiving the configuration update command message, the UE stops timer T3346, if running, and uses the content to update the appropriate information stored within the UE.

[0226] If "request acknowledgement" is indicated in the acknowledgement bit of the configuration update indication IE in the configuration update command message, the UE sends a configuration update complete message.

[0227] If the UE receives a new 5G-GUTI in the CONFIGURATION UPDATE COMMAND message, the UE considers the new 5G-GUTI to be valid, the old 5G-GUTI to be invalid, stops timer T3519 (if running), and deletes any stored Subscription Concealed Identifier (SUCI). Otherwise, the UE considers the old 5G-GUTI to be valid. If the CONFIGURATION UPDATE COMMAND message is sent over non-3GPP access and the UE is in 5GMM-REGISTERED in both 3GPP access and non-3GPP access in the same PLMN, the UE provides the 5G-GUTI to the lower layers of 3GPP access.

[0228] If the UE receives a new TAI list in the CONFIGURATION UPDATE COMMAND message, the UE considers the new TAI list to be valid and the old TAI list to be invalid. Otherwise, the UE considers the old TAI list to be valid.

[0229] If the UE receives a new truncated 5G-S-TMSI configuration in the CONFIGURATION UPDATE COMMAND message, the UE considers the new truncated 5G-S-TMSI configuration to be valid and the old truncated 5G-S-TMSI configuration to be invalid. Otherwise, the UE considers the old truncated 5G-S-TMSI configuration to be valid.

[0230] If the UE receives a new service area list in the CONFIGURATION UPDATE COMMAND message, the UE considers the new service area list to be valid and the old service area list to be invalid. Otherwise, the UE considers the old service area list (if any) to be valid.

[0231] If the UE receives a new network ID and time zone information in the CONFIGURATION UPDATE COMMAND message, the UE considers the new network ID and time zone information to be valid and the old NITZ information to be invalid. Otherwise, the UE considers the old network ID and time zone information to be valid.

[0232] If the UE receives a LADN information IE in the CONFIGURATION UPDATE COMMAND message, the UE considers the old LADN information to be invalid and the new LADN information to be valid (if any). Otherwise, the UE considers the old LADN information to be valid.

[0233] If the UE receives a new allowed NSSAI for the associated access type in the CONFIGURATION UPDATE COMMAND message, the UE considers the new allowed NSSAI to be valid for the associated access type, stores the allowed NSSAI for the associated access type and considers the old allowed NSSAI for the associated access type to be invalid. Otherwise, the UE considers the old allowed NSSAI to be valid for the associated access type.

[0234] If the UE receives a newly configured NSSAI in the CONFIGURATION UPDATE COMMAND message, the UE considers the newly configured NSSAI for the registered PLMN to be valid and considers the old configured NSSAI for the registered PLMN to be invalid. Otherwise, the UE considers the old configured NSSAI for the registered PLMN to be valid. The UE stores the newly configured NSSAI.

[0235] If the UE receives a network slice indication IE with network slice subscription change indication set to "change network slice subscription" in the CONFIGURATION UPDATE COMMAND message, the UE deletes the network slice information for each and every PLMN except the current PLMN.

[0236] If the UE receives an operator-defined access category definition IE in the CONFIGURATION UPDATE COMMAND message and the operator-defined access category definition IE contains one or more operator-defined access category definitions, the UE deletes any operator-defined access category definitions stored for the registered PLMN (RPLMN) and stores the operator-defined access category definitions received for the RPLMN. If the UE receives an operator-defined access category definition IE in the CONFIGURATION UPDATE COMMAND message and the operator-defined access category definition IE does not contain an operator-defined access category definition, the UE deletes any operator-defined access category definitions stored for the RPLMN. If the CONFIGURATION UPDATE COMMAND message does not contain an operator-defined access category definition IE, the UE does not delete the operator-defined access category definitions stored for the RPLMN.

[0237] If the UE receives an SMS indication IE in the CONFIGURATION UPDATE COMMAND message with SMS availability indication set to:

[0238] a) "SMS not available over NAS": the UE considers that the network does not allow SMS transport over NAS; and

[0239] b) "SMS available over NAS": the UE can request the use of SMS transfer over NAS by performing a registration procedure for mobility and periodic registration update after completing the UE configuration update procedure.

[0240] If the UE receives a CAG information list IE in the CONFIGURATION UPDATE COMMAND message, the UE deletes any stored CAG information list and, if the value part of the CAG information list IE is non-empty, stores the CAG information list received in the CAG information list IE.

[0241] If the received CAG information list includes an entry containing the identity of the current PLMN, the UE operates as follows.

[0242] a) if the UE receives the configuration update command message via a CAG cell, the entry for the current PLMN in the received CAG information list does not include any of the CAG-IDs supported by the current CAG cell, and:

[0243] 1) the entry for the current PLMN in the received CAG information list does not include an indication that the UE is only allowed to access the 5GS via CAG cells, the UE enters state 5GMM-REGISTERED.LIMITED-SERVICE and searches for a suitable cell with the updated CAG information list; or

[0244] 2) the entry for the current PLMN in the received CAG information list includes an indication that the UE is only allowed to access the 5GS via CAG cells and:

[0245] i) if the entry for the current PLMN in the received CAG information list includes one or more CAG-IDs, the UE enters state 5GMM-REGISTERED.LIMITED-SERVICE and searches for a suitable cell with the updated CAG information list; or

[0246] ii) if the entry for the current PLMN in the received CAG information list does not include any CAG-IDs and:

[0247] A) the UE does not have an emergency PDU session, the UE enters state 5GMM-DEREGISTERED.PLMN-SEARCH and applies the PLMN selection procedure with the updated CAG information list; or

[0248] B) the UE has an emergency PDU session, the UE performs a local release of all PDU sessions associated with 3GPP access except for the emergency PDU session; or

[0249] b) if the UE receives the configuration update command message via a non-CAG cell and the entry for the current PLMN in the received CAG information list includes an indication that the UE is only allowed to access the 5GS via CAG cells and:

[0250] 1) if the allowed CAG list for the current PLMN in the received CAG information list includes one or more CAG-IDs, the UE enters state 5GMM-REGISTERED.LIMITED-SERVICE and searches for a suitable cell with the updated CAG information list; or

[0251] 2) if the entry for the current PLMN in the received CAG information list does not include any CAG-IDs and:

[0252] i) the UE does not have an emergency PDU session, the UE enters state 5GMM-DEREGISTERED.PLMN-SEARCH and applies the PLMN selection procedure with the updated CAG information list; or

[0253] ii) the UE has an emergency PDU session, the UE performs local release of all PDU sessions associated with 3GPP access except for the emergency PDU session.

[0254] if the configuration update command message indicates "registration requested" in the registration request bit of the configuration update indication IE and:

[0255] a) does not contain other parameters or contains at least one of the following parameters: new allowed NSSAI, new configured NSSAI, or network slice subscription change indication, and:

[0256] 1) there is an emergency PDU session, after completing the UE configuration update procedure and releasing the emergency PDU session, the UE releases the existing N1 NAS signaling connection and starts the registration procedure for mobility and periodic registration update; or

[0257] 2) there is no emergency PDU session, after completing the UE configuration update procedure and releasing the existing N1 NAS signaling connection, the UE starts the registration procedure for mobility and periodic registration update;

[0258] b) includes the MICO indication without new allowed NSSAI or new configured NSSAI, after completing the UE configuration update procedure, the UE starts the registration procedure for mobility and periodic registration update to re-negotiate the MICO mode with the network.

[0259] The UE that receives the rejected NSSAI in the configuration update command message takes the following actions based on the rejection cause in the rejected S-NSSAI.

[0260] "S-NSSAI is not available in the current PLMN or SNPN": the UE adds the rejected S-NSSAI in the rejected NSSAI for the current PLMN and does not attempt to use the S-NSSAI in the current PLMN, remove the Universal Integrated Circuit Card (UICC) containing the Universal SIM (USIM), or update the entry of the "list of subscriber data" with the SNPN ID of the current SNPN until the UE is switched off.

[0261] - "S-NSSAI not available in current registration area": the UE adds the rejected S-NSSAI in the rejected NSSAI for the current registration area and does not attempt to use this S-NSSAI in the current registration area until the UE is powered off, the UE moves out of the current registration area, removes the UICC containing the USIM, or updates the entry of the "List of subscriber data" with the SNPN ID of the current SNPN.

[0262] - "S-NSSAI not available due to failed or revoked network slice specific authentication and authorization": the UE adds the rejected S-NSSAI in the rejected NSSAI for the failed or revoked NSSAA and does not attempt to use this S-NSSAI in the current PLMN over any access until the UE is powered off or updates the entry of the "List of subscriber data" with the SNPN identity of the current SNPN.

[0263] If the UE receives the T3447 value IE in the CONFIGURATION UPDATE COMMAND message and has indicated "Support of service gap control" in the REGISTRATION REQUEST message, the UE replaces the stored T3447 value with the received value in the T3447 value IE and, if neither is zero nor deactivated, the next time it starts, it uses the received T3447 value together with the timer T3447. If the received T3447 value is zero or is deactivated, the UE stops the timer T3447 at runtime.

[0264] If the UE is not in NB-N1 mode, the UE has set the Radio Capability Signaling Optimization (RACS) bit in the 5GMM capability IE of the REGISTRATION REQUEST message to "RACS supported" and the CONFIGURATION UPDATE COMMAND message includes:

[0265] a) the UE Radio Capability ID deletion indication IE set to "UE Radio Capability ID assigned by the network requested to be deleted": the UE deletes any network-assigned UE Radio Capability ID associated with the RPLMN or RSNPN stored at the UE, then the UE initiates the registration procedure for mobility and periodic registration update, and

[0266] b) the UE Radio Capability ID IE: the UE stores the UE Radio Capability ID.

[0267] If the UE is not currently registered for emergency services and the 5GS registration result IE in the CONFIGURATION UPDATE COMMAND message is set to "Registered for emergency services", the UE considers itself registered for emergency services.

[0268] Upon reception of the CONFIGURATION UPDATE COMPLETE message, the AMF stops the timer T3555.

[0269] If a new 5G-GUTI is included in the configuration update command message, the AMF considers the new 5G-GUTI to be valid and the old 5G-GUTI to be invalid.

[0270] If a new TAI list is included in the configuration update command message, the AMF considers the new TAI list to be valid and the old TAI list to be invalid.

[0271] If a new truncated 5G-S-TMSI configuration is included in the configuration update command message, the AMF considers the new truncated 5G-S-TMSI configuration to be valid and the old truncated 5G-S-TMSI configuration to be invalid.

[0272] If a new service area list is included in the configuration update command message, the AMF considers the new service area list to be valid and the old service area list to be invalid.

[0273] If a new allowed NSSAI information is included in the configuration update command message, the AMF considers the new allowed NSSAI information to be valid and the old allowed NSSAI information to be invalid. If a new configured NSSAI information is included in the configuration update command message, the AMF considers the new configured NSSAI information to be valid and the old configured information to be invalid. If there are valid PDU sessions associated with S-NSSAI(s) that are not included in the new allowed NSSAI, the AMF notifies the SMF(s) associated with these PDU sessions to initiate PDU session release procedure requested by the network.

[0274] If the "registration requested" is indicated in the registration request bit of the configuration update indication IE in the configuration update command message and:

[0275] a) the configuration update command message contains:

[0276] 1) allowed NSSAI, configured NSSAI or both;

[0277] 2) network slice indication IE with network slice subscription change indication set to "change network slice subscription"; or

[0278] 3) no other parameters; and

[0279] b) no emergency PDU session has been established for the UE;

[0280] then the AMF initiates release of the N1 NAS signaling connection.

[0281] If the LADN information IE is included in the configuration update command message, the AMF shall consider the old LADN information invalid and the new LADN information valid, if any. In this case, if the list of tracking area identities received in the new LADN information does not include the current TA, the AMF instructs the SMF to release the PDU session for the LADN or release the user plane resources of the PDU session for the LADN.

[0282] If the T3447 value is included in the configuration update command message, the AMF considers the T3447 value valid and, if neither zero nor deactivated, uses the T3447 value with timer T3447 the next time it starts. If the T3447 value included in the configuration update command message contains an indication of timer deactivation or the timer value is zero, the AMF stops timer T3447 when running.

[0283] If the CAG information IE is included in the configuration update command message, the AMF considers the new list of CAG information valid and the old list of CAG information invalid.

[0284] If the UE radio capability ID IE is included in the configuration update command message, the AMF considers the new UE radio capability ID valid and the old UE radio capability ID invalid.

[0285] Hereinafter, minimization of service interruption (MINT) will be described and can refer to S3.1 and S6.31 of 3GPP TS 22.261 V17.2.0 (2021-03).

[0286] The most effective method to prevent interruption of communication services at the time of a disaster is to use roaming. That is, if communication services cannot be received from a communication carrier to which a user subscribes due to a disaster, interruption of communication services can be prevented by roaming to another nearby communication carrier network to receive communication services. More specifically, each communication carrier can actively install a wireless network and a core network in a region (e.g., a country) licensed thereto. Different communication carriers can construct networks and / or install core network nodes in different buildings in different ways, so even if a disaster occurs, all communication carriers are not equally affected. That is, a problem occurring in one communication carrier can be less likely to occur equally in another communication carrier.

[0287] In 3GPP Rel-17, MINT in which a UE receiving communication services from a communication carrier affected by a disaster roams to a network of another communication carrier so that communication services can be continuously received in the case where a disaster occurs is being discussed.

[0288] Figure 7 The concept of MINT, which applies the implementation of this disclosure, is shown.

[0289] Reference Figure 7 In the event of a disaster, roaming operators can accommodate the disaster operator's subscribers by broadcasting the disaster operator's PLMN identifier. Furthermore, to accommodate disaster operator subscribers in the event of a disaster, the disaster operator's PLMN identifier is registered in the roaming operator's core network. The wireless network broadcasts the corresponding PLMN identifier in an SIB message, and traffic can be transmitted between the core networks of the operators.

[0290] To enable third parties to accommodate their roaming subscribers in the event of their own communications failure and / or third-party subscribers in the event of a third party's communications failure, each operator can build core network nodes (e.g., MME, S-GW, P-GW) for disaster roaming.

[0291] Under normal circumstances, the corresponding systems should be prepared to accept roaming calls through initial network interconnection between operators, and in the event of a communication disaster, subsequent measures should be taken according to the occurrence criteria to accommodate roaming calls between operators. These pre- and post-operation measures can follow the agreements between the operators.

[0292] exist Figure 7 The example shown is the application of MINT in the Evolved Packet System (EPS), but MINT can also be applied in 5G systems.

[0293] Regarding MINT, the following terms can be defined.

[0294] - Disaster Situation: This is a situation where the government decides when to initiate and terminate (e.g., a natural disaster). When this situation applies, users have the opportunity to mitigate service interruptions and failures.

[0295] - Disaster inbound roamers: (a) users who are unable to obtain services from the PLMN normally served by them due to service failures during a disaster situation and (b) users who are able to register with other PLMNs.

[0296] - Disaster Roaming: This is a special roaming strategy applied during disaster situations.

[0297] Regarding MINT, the following needs can be considered.

[0298] In the event of a disaster (e.g., fire), a mobile network can not be able to provide service. The 5GS can provide functionality to mitigate service interruption. If there is a PLMN operator that is prepared to provide service, the UE can obtain service from the corresponding PLMN in the event of a disaster. MINT is limited to a specific time and place. To reduce the impact on the 5G system supporting disaster roaming, potential congestion due to inflow or outflow of disaster inbound roamers is considered.

[0299] Subject to regulatory requirements or operator's policy, the 3GPP system can be able to enable UEs of a given PLMN to obtain connectivity services (e.g., voice call, mobile data service) from another PLMN for the area where disaster conditions apply.

[0300] The 3GPP system can enable UEs to obtain information that disaster conditions apply to a specific PLMN or PLMNs.

[0301] If a UE does not have coverage of its home PLMN (HPLMN), to obtain information that disaster conditions apply to the UE's HPLMN, the UE can register to a PLMN that provides disaster roaming service.

[0302] The 3GPP system can support means for a PLMN operator to be aware of the area where disaster conditions apply.

[0303] The 3GPP system can be able to support providing service to disaster inbound roamers only within a specific area where disaster conditions apply.

[0304] The 3GPP system can be able to provide efficient means for the network to inform disaster inbound roamers that disaster conditions no longer apply.

[0305] Subject to regulatory requirements or operator's policy, the 3GPP system can support a PLMN operator to be aware of the failure or recovery of other PLMNs in the same country when disaster conditions apply, or when disaster conditions do not apply.

[0306] The 3GPP system can be able to provide means to enable UEs to access a PLMN in a forbidden PLMN list when disaster conditions apply and there is no other PLMN available except the PLMNs in the forbidden PLMN list.

[0307] The 3GPP system can provide means to enable disaster conditions to apply to UEs of a specific PLMN.

[0308] The 3GPP system can be able to provide resource efficient means for a PLMN to indicate to potential disaster inbound roamers whether they can access the PLMN.

[0309] When the disaster situation has ended, the disaster inbound roamer can perform network reselection.

[0310] The 3GPP system can minimize congestion caused by disaster roaming.

[0311] The 3GPP system can be able to collect charging information of disaster inbound roamers as well as information about the applicable disaster situation.

[0312] Regarding access control for UEs satisfying the disaster situation, access identity number 4 can be applied. This configuration is valid for indicating to the potential disaster inbound roamer the PLMN to which the UE can access.

[0313] Regarding MINT, network selection can be performed as follows.

[0314] At switch-on, when in the coverage of the last registered PLMN stored in the SIM / USIM, the UE attaches to that network.

[0315] As an option, in automatic selection mode, when there is no Equivalent HPLMN (EHPLMN) list, the UE can select the HPLMN. When there is an EHPLMN list, the UE can select the highest priority EHPLMN among the available EHPLMNs. The operator can be able to control the UE behavior through USIM configuration.

[0316] As an option, if the UE is in manual network selection mode at switch-on

[0317] - if the last registered PLMN is not available and no equivalent PLMN is available, and

[0318] - and the UE finds that it is in the coverage of the HPLMN or EHPLMN

[0319] then the UE can register on the corresponding HPLMN or EHPLMN. The UE remains in manual network selection mode.

[0320] If the UE returns to coverage of its registered PLMN (as indicated by the registered PLMN stored in the SIM / USIM), the UE can perform a location update to the new location area if necessary. As an alternative to this, if the UE is in automatic network selection mode and it finds coverage of the HPLMN or any EHPLMN, the UE can register on the HPLMN (if no EHPLMN list exists) or the highest priority EHPLMN (if an EHPLMN list exists) of the available EHPLMNs without returning to the last registered PLMN. If an EHPLMN list exists and is not empty, it can be used. The operator can be able to control through USIM configuration whether UEs supporting this option should follow this alternative behaviour.

[0321] The default behaviour for the UE is to select the last registered PLMN.

[0322] If no registered PLMN is stored in the SIM / USIM, or if this PLMN is not available and no equivalent PLMN is available, or the attempted registration failed, the UE can follow one of the following procedures for network selection.

[0323] A) Automatic network selection mode

[0324] If the location area is not in the "Prohibited LA for roaming" list and the tracking area is not in the "Prohibited TA for roaming" list, the UE can select and attempt to register on other PLMNs (if available or allowed) in the following order.

[0325] i) For the preferred access technology in the specified order, if an EHPLMN list exists, the EHPLMNs; or if no EHPLMN list exists, the HPLMN (derived from IMSI). In case there are multiple EHPLMNs, then the highest priority EHPLMN is selected.

[0326] ii) Each entry (in priority order) in the "User controlled PLMN selector with access technology" data field in the SIM / USIM.

[0327] iii) Each entry (in priority order) in the "Operator controlled PLMN selector with access technology" data field in the SIM / USIM.

[0328] iv) Other PLMN / access technology combinations with sufficient received signal quality in a random order.

[0329] v) All other PLMN / access technology combinations in order of decreasing signal quality.

[0330] A UE with voice capability can be configured so that it shall not attempt to register on a PLMN if all cells identified as belonging to the PLMN do not support the corresponding voice service.

[0331] In case the UE is operating in UE operation mode A or B, the allowed PLMNs are the PLMNs not in the forbidden PLMN data field in the SIM / USIM. This data field can be extended in the mobile equipment (ME) memory. In case the UE is operating in UE operation mode C, the allowed PLMNs are the PLMNs not in the forbidden PLMN data field in the SIM / USIM or in the forbidden PLMN list for GPRS service in the ME. When there are no available PLMNs in the forbidden PLMN data field in the SIM / USIM except the PLMN and the available PLMN indicates that a disaster situation applies, this PLMN can be considered as allowed to be registered to the UE when a disaster situation applies.

[0332] If a successful registration is achieved, the UE can indicate the selected PLMN.

[0333] If registration cannot be achieved on any PLMN and at least one PLMN providing restricted local operator services has been found, the UE can obtain the user consent for restricted local operator services and the UE can use the list of preferred PLMNs for restricted local operator services stored in the ME. If none of the preferred PLMNs for restricted local operator services are available, the UE can select any available PLMN providing restricted local operator services. If one of these PLMNs for restricted local operator services is selected, the UE can indicate the selection. If not, the UE can wait until a new PLMN is detected or a new location area or tracking area of an allowed PLMN not in the forbidden LA or TA list is found and then repeat the procedure.

[0334] If registration cannot be achieved on any PLMN and no PLMN providing restricted local operator services has been found, the UE can indicate "no service" to the user, wait until a new PLMN is detected or a new location area or tracking area of an allowed PLMN not in the forbidden LA or TA list is found and then repeat the procedure. When registration cannot be achieved, different (discontinuous) PLMN search schemes can be used in order to minimize the access time while preserving the battery life, for example by prioritizing the search in favor of broadcast control channel (BCCH) carriers, which have a high probability of belonging to available and allowable PLMNs.

[0335] B) Manual network selection mode

[0336] The UE can indicate the available PLMNs (including forbidden PLMNs). If not, this can also be indicated. The user's HPLMN can provide additional information on available PLMNs on the USIM, if provided, which the UE can indicate to the user. This information, provided as free text, can include the following.

[0337] - Preferred partners,

[0338] - Roaming agreement status,

[0339] - Supported services

[0340] In addition, the UE can indicate whether the available PLMNs exist on one of the PLMN selector lists (e.g. EHPLMNs, user controlled, operator controlled or forbidden) and whether none exist on any of the lists.

[0341] For the purpose of presenting the names of the available PLMNs to the user, the ME can use the names defined by the USIM (if available) or other PLMN naming rules in order of priority (country / PLMN indication).

[0342] Any available PLMNs are presented in the following order.

[0343] i) HPLMN (if the EHPLMN list is not present); or if one or more of the EHPLMNs are available, the highest priority available EHPLMN is presented to the user based on an optional data field on the USIM, or all available EHPLMNs are presented to the user in order of priority. If the data field is not present, only the highest priority available EHPLMN is presented.

[0344] ii) PLMNs contained in the "User Controlled PLMN Selector" data field in the SIM / USIM (in order of priority)

[0345] iii) PLMNs in the "Operator Controlled PLMN Selector" data field in the SIM / USIM (in order of priority).

[0346] iv) Other PLMN / access technology combinations with sufficient received signal level in a random order.

[0347] v) All other PLMN / access technology combinations in order of signal strength decline.

[0348] If a PLMN does not support voice services, this is indicated to the user.

[0349] The user can select a desired PLMN and the UE attempts to register on that PLMN (this can happen at any time during the presence of the PLMN).

[0350] If registration cannot be achieved on any PLMN and at least one PLMN providing restricted local operator services has been discovered, the UE can obtain the user's consent for restricted local operator services and propose the user to select one of these networks. If one of these networks is selected, the UE can indicate the selected PLMN, wait until a new PLMN location is detected or a new location area or tracking area of a permitted PLMN not in the forbidden LA or TA list is discovered, and then repeat the procedure.

[0351] If registration cannot be achieved on any PLMN and no PLMN providing restricted local operator services is selected, the UE can indicate "no service". The user can then follow the above procedure to select and attempt registration on another or the same PLMN. The UE shall not attempt registration on a PLMN that has not been selected by the user.

[0352] Once the UE has registered on a PLMN selected by the user, the UE does not automatically register on a different PLMN unless:

[0353] i) the new PLMN is declared as equivalent PLMN by the PLMN on which the UE is registered; or,

[0354] ii) the user selects the automatic mode.

[0355] If a PLMN is selected but the UE cannot register on it because the registration was rejected for the reason "PLMN not allowed", the UE can add this PLMN to the list of forbidden PLMNs. The UE shall not re-attempt registration on this network unless the user selects the same PLMN again.

[0356] If a PLMN is selected but the UE cannot register on it for packet switched (PS) services because the registration was rejected for the reason "GPRS services not allowed in this PLMN", the UE shall not re-attempt registration on this network for E-UTRAN or UTRAN PS or GSM EDGE Radio Access Network (GERAN) PS. The PLMN is added to the list "PLMNs forbidden for GPRS services". The UE shall not re-attempt registration on this network for E-UTRAN or UTRAN PS or GERAN PS unless the user selects the same PLMN again. Receiving the reason "GPRS services not allowed in this PLMN" has no impact on CS services.

[0357] If a PLMN is selected but the UE cannot register on it for other reasons, the UE can attempt to register on the PLMN when a new LA of the selected PLMN is detected (not in the list of barred LAs).

[0358] If the UE is registered on a PLMN but loses coverage, a different (discontinuous) carrier search scheme can be used, for example by prioritizing the search for BCCH carriers that favor the registered PLMN to minimize the time to find a new active BCCH carrier and preserve battery life.

[0359] When the UE's registration attempt is rejected by a network with an indication of a "permanent" PLMN restriction, the PLMN identity can be written into a list of barred PLMNs stored in a data field in the SIM / USIM.

[0360] If a successful registration is achieved on a PLMN in the list of barred PLMNs, the corresponding PLMN can be removed from the list. However, if a successful registration is achieved on a PLMN in the list of barred PLMNs when a disaster situation applies, the PLMN can not be removed from the list of barred PLMNs.

[0361] When in automatic mode, the UE can indicate any PLMN that will not be selected due to the PLMN being present in the list of barred PLMNs.

[0362] If the UE receives an equivalent PLMN list containing a PLMN included in the list of barred PLMNs, the PLMN can be removed from the equivalent PLMN list before the UE stores it.

[0363] When a disaster situation occurs in a particular PLMN (hereinafter referred to as a first PLMN) (i.e., when a disaster situation is satisfied), disaster roaming is applied so that the UE can receive disaster roaming services from a nearby PLMN (hereinafter referred to as a second PLMN) that supports disaster roaming. Thereafter, the first PLMN can be restored while the UE receives disaster roaming services through the second PLMN. In this case, the network should notify the UE receiving disaster roaming services of the restoration of the first PLMN (i.e., the disaster situation is no longer satisfied) through the first PLMN and / or the second PLMN.

[0364] While providing voice services to the UE through the second PLMN, the fact that the first PLMN has recovered can be notified. In this case, the second PLMN can deregister all UEs introduced from the first PLMN (i.e., disaster inbound roamers) from the second PLMN. Alternatively, the UE can immediately stop the services provided from the second PLMN, perform PLMN selection, and move to the recovered first PLMN as soon as the recovery of the first PLMN is notified. In either case, the services being currently provided are interrupted, which can deteriorate the user experience.

[0365] Hereinafter, according to implementations of the disclosure, while the UE receives disaster roaming services from the second PLMN when a disaster occurs in the first PLMN, a method of minimizing interruption of communication services provided to the UE by effectively notifying the UE of the recovery of the first PLMN is described.

[0366] Hereinafter, the UE and the terminal can be used interchangeably. The various implementations and / or embodiments of the disclosure to be described below can be applied to various services such as eMBB, V2X communication, public safety, IoT, etc. In addition, the various implementations and / or embodiments of the disclosure to be described below can be applied to various types of terminals, for example, a smartphone, a vehicle, an IoT terminal, a robot, etc.

[0367] The various implementations and / or embodiments of the disclosure to be described below can be independently performed, or two or more can be combined and thus performed in a complex manner. In addition, a combination of one or more actions / configurations / steps of the various implementations and / or embodiments of the disclosure described below can be performed.

[0368] According to implementations of the disclosure, the AMF of the second PLMN can transmit a configuration update command message to the UE. In this case, the configuration update command message can include information indicating that the disaster situation of the first PLMN (i.e., HPLMN) has ended. Upon receiving the configuration update command message, the UE recognizes that the disaster situation has ended in the HPLMN and responds with a configuration update complete message, but can wait until the services (e.g., voice services) being currently provided in the second PLMN are terminated. Thereafter, when the services provided by the second PLMN are terminated, the UE can immediately deregister from the second PLMN and select the HPLMN again through PLMN selection.

[0369] According to implementations of the disclosure, the AMF of the second PLMN can send a configuration update command message to the UE. In this case, the configuration update command message can include only "request registration" without other information / parameters. Upon receiving the configuration update command message, the UE can respond with a configuration update complete message upon termination of the service (e.g., voice service) being provided by the current second PLMN. When the AMF of the second PLMN performs NAS signaling connection release, the UE can again send a registration request message to the AMF of the second PLMN. The AMF of the second PLMN can respond to this with a registration reject message. The registration reject message can include an MM cause value #xx as a rejection cause, and the MM cause value #xx can indicate that the disaster situation has ended in the first PLMN (i.e., HPLMN), and thus the disaster roaming service cannot be provided in the second PLMN any more. Upon receiving the registration reject message, the UE can transition the MM state to 5GMM.DEREGISTERED for the second PLMN, and select the HPLMN by performing PLMN selection.

[0370] According to implementations of the disclosure, when the UE receives information indicating that the disaster situation has ended in the first PLMN, the UE can update the internal setting that the disaster situation has ended. If the second PLMN was included in the forbidden PLMN list before the disaster situation, the UE can again include the second PLMN in the forbidden PLMN list.

[0371] The following figures are created in order to illustrate the specific embodiments of the disclosure. The names of specific apparatuses or the names of specific signals / messages / fields shown in the figures are presented for example purposes, and the technical features of the present specification are not limited to the specific names used in the following figures.

[0372] Figure 8 An example of a method performed by a UE to which implementations of the disclosure are applied is illustrated.

[0373] In step S800, the method includes registering in a disaster roaming PLMN and receiving a disaster roaming service.

[0374] In step S810, the method includes receiving, from the disaster roaming PLMN, a configuration update command message including information indicating that a disaster situation of the HPLMN has ended.

[0375] In step S820, the method includes waiting until a service being received from the disaster roaming PLMN ends.

[0376] In step S830, the method includes, after the service received from the disaster roaming PLMN ends, performing a procedure of deregistering from the disaster roaming PLMN based on the information indicating that the disaster situation of the HPLMN has ended.

[0377] In step S840, the method includes selecting the HPLMN and performing registration to the HPLMN.

[0378] In some implementations, the method can further include sending a configuration update complete message to the AMF of the disaster roaming PLMN in response to the configuration update command message.

[0379] In some implementations, the method can further include including the disaster roaming PLMN in a list of forbidden PLMNs.

[0380] In some implementations, the method can further include updating the internal set disaster situation to end based on information indicating that the disaster situation of the HPLMN has ended.

[0381] In some implementations, the configuration update command message can include a configuration update indication IE with a registration request bit set to "registration requested". In this case, registration can not be performed with the disaster roaming PLMN regardless of the registration request bit being set to "registration requested". Also, NAS signaling connection release can not be performed regardless of the registration request bit being set to "registration requested".

[0382] In some implementations, the UE can communicate with at least one of a mobile device, a network, and / or an autonomous vehicle other than the UE.

[0383] Further, the method of the above UE can be performed bythe first wireless device 100 shown in FIG. 1,the wireless device 100 shown in FIG. 2, and / orthe UE 100 shown in FIG. 3. Figure 2 Figure 3 Figure 4 Figure 8

[0384] More specifically, the UE includes at least one transceiver, at least one processor, and at least one memory operably connectable to the at least one processor. The at least one memory stores instructions that cause the at least one processor to perform operations.

[0385] The UE registers in a disaster roaming PLMN and receives a disaster roaming service.

[0386] The UE receives a configuration update command message including information indicating that a disaster situation of the HPLMN has ended from the disaster roaming PLMN.

[0387] The UE waits until the service being received from the disaster roaming PLMN ends.

[0388] ​The UE, after the service being received from the disaster roaming PLMN ends, performs a procedure of deregistering from the disaster roaming PLMN based on information indicating that the disaster situation of the HPLMN ends.

[0389] The UE selects the HPLMN and performs registration to the HPLMN.

[0390] In some implementations, the operations can further include sending a configuration update complete message to the AMF of the disaster roaming PLMN in response to the configuration update command message.

[0391] In some implementations, the operations can further include including the disaster roaming PLMN in a list of barred PLMNs.

[0392] In some implementations, the operations can further include updating an internal setting of a disaster situation to end based on information indicating that the disaster situation of the HPLMN has ended.

[0393] In some implementations, the configuration update command message can include a configuration update indication IE with a registration request bit set to "registration requested". In this case, it can not be possible to perform registration with the disaster roaming PLMN regardless of the registration request bit being set to "registration requested". Also, it can not be possible to perform NAS signaling connection release regardless of the registration request bit being set to "registration requested".

[0394] Further, the method of the above-described UE perspective in Figure 2 may be performed by control of a processor 102 included in the first wireless device 100 shown in Figure 3 may be performed by control of a communication unit 110 and / or a control unit 120 included in the wireless device 100 shown in Figure 4 may be performed by control of a processor 102 included in the UE 100 shown in Figure 8

[0395] More specifically, a processing device operating in a wireless communication system includes at least one processor and at least one memory operatively connectable to the at least one processor. The at least one processor is adapted to perform operations comprising registering in a disaster roaming PLMN and receiving a disaster roaming service, obtaining, from the disaster roaming PLMN, a configuration update command message including information indicating that a disaster situation of an HPLMN has ended, waiting until a service being received from the disaster roaming PLMN ends, after the service being received from the disaster roaming PLMN ends, performing a procedure of deregistering from the disaster roaming PLMN based on the information indicating that the disaster situation of the HPLMN ends, and selecting the HPLMN and performing registration to the HPLMN.

[0396] Further, the method of the above-described UE perspective in Figure 2 ​The software code 105 in the memory 104 included in the first wireless device 100 illustrated in FIG. 1 performs Figure 8 the method of the above-described UE in

[0397] The technical features of the present disclosure can be implemented directly in hardware, in software executed by a processor, or a combination of both. For example, a method performed by a wireless device in wireless communication can be implemented in hardware, software, firmware, or any combination thereof. For example, the software can reside in RAM, flash memory, ROM, EPROM, EEPROM, registers, hard disk, a removable disk, a CD-ROM, or any other storage medium.

[0398] Some examples of storage media can be tangible and non-transitory. In some examples, a storage media can be integral to the processor. The processor and the storage media can reside in an ASIC. In some examples, the processor and the storage media can be discrete components.

[0399] The computer-readable medium can include a tangible and non-transitory computer-readable storage medium.

[0400] For example, the non-transitory computer-readable medium can include RAM, such as synchronous dynamic random access memory (SDRAM), ROM, non-volatile random access memory (NVRAM), EEPROM, flash memory, a magnetic or optical data storage medium, or any other medium that can be used to store the instructions or data structures accessible to the computer. The non-transitory computer-readable medium can also include combinations of the above.

[0401] In addition, the methods described herein can be implemented at least in part by a computer-readable communication medium that carries or communicates code in the form of instructions or data structures and that can be accessed, read, and / or executed by a computer.

[0402] According to some implementations of the present disclosure, a non-transitory computer-readable medium (CRM) has stored thereon a plurality of instructions.

[0403] More specifically, the CRM stores instructions that cause at least one processor to perform operations. The operations include registering in a disaster roaming PLMN and receiving a disaster roaming service, obtaining a configuration update command message including information indicating that a disaster condition of the HPLMN has ended from the disaster roaming PLMN, waiting until the service being received from the disaster roaming PLMN ends, after the service received from the disaster roaming PLMN ends, performing a procedure of deregistering from the disaster roaming PLMN based on the information indicating that the disaster condition of the HPLMN ends, and selecting the HPLMN and performing registration to the HPLMN.

[0404] Hereinafter, various implementations of the present disclosure are described in detail.

[0405] 1. First implementation

[0406] Figure 9 An example of a signaling operation according to the first implementation of the disclosure is shown.

[0407] Figure 8 The method described in the middle can correspond to the first implementation.

[0408] Referring to Figure 9 In the first PLMN (i.e., HPLMN), a disaster occurs (i.e., the first PLMN is in a disaster situation), and the UE roams to the second PLMN (i.e., a disaster roaming PLMN) according to the disaster roaming and is served by the second PLMN. The following operations are as follows.

[0409] Step 1: The UE is currently being served by the second PLMN.

[0410] Step 2: The second PLMN identifies that the disaster situation of the first PLMN has ended.

[0411] Step 3: The AMF of the second PLMN sends a configuration update command message to the UE in a connected state receiving service from the second PLMN. The configuration update command message can include information indicating that the disaster situation in the first PLMN has ended. In addition, the configuration update command message can include a configuration update indication IE with a registration request bit set to "request registration".

[0412] Step 4: Upon receiving the configuration update command message including information indicating that the disaster situation in the first PLMN has ended, the UE identifies that the disaster situation in the first PLMN has ended, and responds to the configuration update command message with a configuration update complete message.

[0413] Step 5: The UE waits until the service (e.g., voice service) being provided by the second PLMN is terminated.

[0414] Step 6: When the service being provided in the second PLMN ends, the UE immediately performs a de-registration procedure for the second PLMN. That is, registration to the second PLMN can not be performed even though the configuration update indication IE with the registration request bit set to "request registration" is received via the configuration update command message. In addition, the NAS signaling connection release can not be performed.

[0415] Step 7: The UE can update the disaster situation end of the internal settings. If the second PLMN is included in the forbidden PLMN list before the disaster situation, the UE can include the second PLMN in the forbidden PLMN list again based on the termination of the disaster situation in the first PLMN.

[0416] Step 8: The UE can perform PLMN selection to select the first PLMN again.

[0417] 2. Second implementation

[0418] Figure 10 An example of signaling operation according to the second implementation of the present disclosure is shown.

[0419] Referring to Figure 10 In the first PLMN (i.e., HPLMN), a disaster occurs (i.e., the first PLMN is in a disaster situation), and the UE roams to the second PLMN (i.e., a disaster roaming PLMN) according to disaster roaming and is served by the second PLMN. The following operations are as follows.

[0420] Step 1: The UE is currently being served by the second PLMN.

[0421] Step 2: The second PLMN identifies that the disaster situation of the first PLMN has ended.

[0422] Step 3: The AMF of the second PLMN sends a configuration update command message to the UE in a connected state of receiving service from the second PLMN. Unlike the first implementation described above, the configuration update command message can not include information indicating that the disaster situation in the first PLMN has ended. That is, the configuration update command message can include only a configuration update indication IE in which a registration request bit is set to "request registration".

[0423] Step 4: Upon receiving the configuration update command message, the UE completes the service (e.g., voice service) being provided from the second PLMN.

[0424] Step 5: The UE responds to the configuration update command message with a configuration update complete message.

[0425] However, since the configuration update procedure itself can fail if the service being provided by the second PLMN is prolonged, the UE can send the configuration update complete message within an appropriate time after receiving the configuration update command message in consideration of this. In this case, according to the transmission of the configuration update complete message, the service provided in the second PLMN can inevitably be interrupted.

[0426] Step 6: The UE and the second PLMN perform NAS signaling connection release.

[0427] Step 7: Upon receiving the configuration update indication IE in which the registration request bit is set to "request registration" via the configuration update command message, the UE sends a registration request message to the AMF of the second PLMN.

[0428] Step 8: In response to the registration request message, the AMF of the second PLMN sends a registration reject message to the UE. The registration reject message can include an MM cause value #xx as a rejection cause. The MM cause value #xx can indicate that the disaster situation has ended in the first PLMN and accordingly, the disaster roaming service is no longer provided in the second PLMN.

[0429] Step 9: After receiving the registration reject message including the MM cause value #xx, the UE can transition the MM state for the second PLMN to 5GMM.DEREGISTERED. In addition, the UE can update the internally set disaster situation has ended. If the second PLMN was included in the forbidden PLMN list before the disaster situation, the UE can include the second PLMN in the forbidden PLMN list again based on the termination of the disaster situation in the first PLMN.

[0430] Step 10: The UE can perform PLMN selection to select the first PLMN again.

[0431] The present disclosure can have various advantageous effects.

[0432] For example, when the disaster situation ends, the UE that has used disaster roaming from a disaster roaming communication network can return to the original communication network without interruption after normally ending the ongoing service, thereby improving the user experience of the UE.

[0433] The advantageous effects that can be obtained through specific embodiments of the present disclosure are not limited to the advantageous effects enumerated above. For example, there can be various technical effects that can be understood and / or inferred by those of ordinary skill in the related art from the present disclosure. Therefore, specific effects of the present disclosure are not limited to the effects explicitly described herein, but can include various effects that can be understood or inferred from the technical features of the present disclosure.

[0434] The claims in the present disclosure can be combined in various ways. For example, the technical features in the method claims of the present disclosure can be combined to be implemented or performed in a device, and the technical features in the device claims can be combined to be implemented or performed in a method. Also, the technical features in the method claims and the device claims can be combined to be implemented or performed in a device. Also, the technical features in the method claims and the device claims can be combined to be implemented or performed in a method. Other implementations are within the scope of the appended claims.

Claims

1. A method performed by a user equipment, UE, the method comprising: receiving, from an access and mobility management function, AMF, of a second public land mobile network, PLMN, a configuration update command message based on a disaster situation no longer applying to a first PLMN, the configuration update command message including a configuration update indication information element, IE, with a registration requested bit notifying that a registration is requested; sending, to the AMF of the second PLMN, a registration request message based on the configuration update command message notifying the registration is requested in the registration requested bit of the configuration update indication IE; receiving a registration reject message from the AMF of the second PLMN; and performing a PLMN selection. The method further comprises sending a configuration update complete message to the AMF of the second PLMN in response to the configuration update command message.

2. The method of claim 1, wherein, The method further comprises including the second PLMN in a list of barred PLMNs.

3. The method of claim 1, wherein, The method further comprises updating an internal set disaster scenario to end.

4. The method of claim 1, wherein, The registration reject message includes a mobility management, MM, cause value notifying that a disaster roaming service cannot be provided in the second PLMN.

5. The method of claim 1, wherein, The UE communicates with at least one of a mobile device, a network, and / or an autonomous vehicle other than the UE.

6. The method of claim 1, wherein, 7. A user equipment, UE, the UE comprising: at least one processor; and at least one memory operably connectable to the at least one processor and storing instructions that, based on execution by the at least one processor, perform operations comprising: receiving, via at least one transceiver, from an access and mobility management function, AMF, of a second public land mobile network, PLMN, a configuration update command message based on a disaster situation no longer applying to a first PLMN, the configuration update command message including a configuration update indication information element, IE, with a registration requested bit notifying that a registration is requested; sending, via the at least one transceiver, to the AMF of the second PLMN, a registration request message based on the configuration update command message notifying the registration is requested in the registration requested bit of the configuration update indication IE; receiving, via the at least one transceiver, a registration reject message from the AMF of the second PLMN; and performing a PLMN selection. The operations further comprise the method of any of claims 2-6.

9. An access and mobility management function, AMF, of a second public land mobile network, PLMN, the AMF comprising:

8. The UE of claim 7, wherein, at least one processor; and at least one memory operably connectable to the at least one processor and storing instructions that, based on execution by the at least one processor, perform operations comprising: performing a registration user equipment, UE, for disaster roaming; providing a disaster roaming service to the UE; sending, to the UE, a configuration update command message based on a disaster situation no longer applying to a first PLMN, the configuration update command message including a configuration update indication information element, IE, with a registration requested bit notifying that a registration is requested; ​ ​ notify the registration is requested in the registration request bit of the configuration update indication IE based on the configuration update command message, receive a registration request message from the UE; and send a registration reject message to the UE.

Images