Pdu session management method

Abstract

One disclosure of the specification provides a method of a policy control function (PCF) performing communication. The method includes the steps of: receiving a UE policy association establishment (UE association establishment) message from an access and mobility management function (AMF); and transmitting a user equipment (UE) route selection policy (URSP) rule to a UE, wherein the URSP rule includes a first route selection descriptor (RSD) and a second RSD, the first RSD includes a protocol data unit (PDU) session pair identifier (ID), the PDU session pair ID is used to establish two redundant PDU sessions, and the second RSD does not include the PDU session pair ID.

Description

TECHNICAL FIELD

[0001] The present specification relates to mobile communications. BACKGROUND

[0002] The 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) is a technology for enabling high-speed packet communications. Many schemes have been proposed for the LTE objective including those that aim to reduce user and provider costs, improve service quality, and expand and improve coverage of and system capacity. As an upper layer of requirements, 3GPP LTE needs to support costs, increase service availability, flexibly use frequency bands, have a structurally simple architecture, have open interfaces, and have sufficient power consumption of terminals.

[0003] Requirements and specifications have been started for New Radio (NR) systems in the International Telecommunication Union (ITU) and 3GPP. 3GPP must identify and develop the technology components needed for successful standardization of the new RAT that will meet the immediate and longer-term requirements of the IMT-2020 process as set out by the ITU Radio communication Sector (ITU-R). In addition, NR should be able to use any spectrum band between 6 GHz and 300 GHz that can be made available for wireless communications even in a more distant future. NR should also be able to use different spectrum bands dynamically depending on availability and requirements.

[0004] The goal of NR is to provide 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. SUMMARY

[0005] TECHNICAL PROBLEM

[0006] A network needs to comprehensively manage a terminal that does not support a PDU session pair ID and a terminal that supports a PDU session pair ID.

[0007] TECHNICAL SOLUTION

[0008] A URSP rule for a terminal that supports a PDU session pair ID and a URSP rule for a terminal that does not support a PDU session pair ID can be created and transmitted to the terminal.

[0009] ADVANTAGEOUS EFFECTS

[0010] The present specification can have various effects.

[0011] For example, by the procedure disclosed in the present specification, a network can establish a redundant PDU session by comprehensively managing a terminal that supports a PDU session pair ID and a terminal that does not support a PDU session pair ID.

[0012] The effects obtainable through the specific examples of the present specification are not limited to the above-listed effects. For example, there can be various technical effects that can be understood or inferred by those of ordinary skill in the related art from the present specification. Accordingly, the specific effects of the present specification are not limited to those explicitly described herein, and can include various effects that can be understood or inferred from the technical features of the present specification. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 An example of a communication system to which implementations of the present disclosure is applied is shown.

[0014] Figure 2 An example of a wireless device to which implementations of the present disclosure is applied is shown.

[0015] Figure 3 An example of a wireless device to which implementations of the present disclosure is applied is shown.

[0016] Figure 4 An example of a UE to which implementations of the present disclosure is applied is shown.

[0017] Figure 5 An example of a redundant user plane path using dual connectivity is shown.

[0018] Figure 6 A first example of the first embodiment of the present specification is shown.

[0019] Figure 7 and Figure 8 A second example of the first embodiment of the present specification is shown.

[0020] Figure 9 , Figure 10 , Figure 11 and Figure 12 An example of the third embodiment of the present specification is shown.

[0021] Figure 13 and Figure 14 An example of the fourth embodiment of the present specification is shown.

[0022] Figure 15 An example of the fifth embodiment of the present specification is shown.

[0023] Figure 16 A procedure for a PCF of the disclosure of the present specification is shown.

[0024] Figure 17 A procedure for a UE of the disclosure of the present specification is shown. DETAILED DESCRIPTION

[0025] 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. The CDMA can be embodied through radio technology such as universal terrestrial radio access (UTRA) or CDMA2000. The TDMA can be embodied through radio technology such as global system for mobile communications (GSM), general packet radio service (GPRS), or enhanced data rates for GSM evolution (EDGE). The OFDMA can be embodied through 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). The UTRA is a part of a universal mobile telecommunications system (UMTS). A 3rd generation partnership project (3GPP) long term evolution (LTE) is a part of an evolved UMTS (E-UMTS). The 3GPP LTE employs the OFDMA in a DL and employs the SC-FDMA in a UL. Evolutions of the 3GPP LTE include LTE-A (LTE-Advanced), LTE-A Pro, and / or 5G NR (New Radio).

[0026] For the convenience of description, implementation modes 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, which are not limited to the 3GPP-based wireless communication system, are applicable to other mobile communication systems.

[0027] For terms and technologies not specifically described among terms and technologies employed in the disclosure, reference can be made to wireless communication standard documents published before the disclosure.

[0028] In the disclosure, "A or B" can mean "A only," "B only," or "both A and B." In other words, "A or B" in the disclosure can be interpreted as "A and / or B." For example, "A, B, or C" in the disclosure can mean "A only," "B only," "C only," or "any combination of A, B, and C."

[0029] 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."

[0030] In the disclosure, "at least one of A and B" can mean "only A", "only B", or "both A and B". Also, the expression "at least one of A or B" or "at least one of A and / or B" in the disclosure can be interpreted to be the same as "at least one of A and B".

[0031] Also, 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". Also, "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".

[0032] Also, the brackets 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" in the disclosure is not limited to "PDCCH", and "PDCCH" can be proposed as an example of "control information". Also, even when shown as "control information (i.e., PDCCH)", "PDCCH" can be proposed as an example of "control information".

[0033] The technical features described in one drawing in the disclosure can be implemented alone or simultaneously.

[0034] Although not limited thereto, various descriptions, functions, procedures, 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).

[0035] Hereinafter, the disclosure will be described in greater detail with reference to the accompanying drawings. Unless otherwise indicated, the same numbers in the following drawings and / or description can represent the same and / or corresponding hardware blocks, software blocks, and / or functional blocks.

[0036] Figure 1 An example of a communication system to which implementations of the disclosure are applied is illustrated.

[0037] Figure 1 The illustrated 5G usage scenarios are merely exemplary, and the technical features of the disclosure can be applied to other 5G usage scenarios not illustrated in Figure 1

[0038] 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.

[0039] Referring to Figure 1 , the communication system 1 includes wireless devices 100a to 100f, base stations (BSs) 200, and a network 300. Although FIG. 1 shows the communication system 1 including six wireless devices 100a to 100f, six BSs 200, and one network 300, the number of wireless devices 100a to 100f, the number of BSs 200, and the number of networks 300 are not limited to the illustrated example.​Figure 1 A 5G network is shown as an example of a network of the communication system 1, but implementations of the disclosure are not limited to the 5G system, and are applicable to future communication systems beyond the 5G system.

[0040] The BS 200 and the network 300 can be implemented as wireless devices, and a particular wireless device can operate as a BS / network node with respect to other wireless devices.

[0041] The wireless devices 100a to 100f represent devices that perform communication using a radio access technology (RAT) such as 5G New RAT (NR) or LTE, and can be referred to as communication / radio / 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, self-driving vehicles, and vehicles capable of performing communication between vehicles. The vehicles can include unmanned aerial vehicles (UAVs) such as 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, a digital signage, a vehicle, a robot, etc. The handheld device can include a smartphone, a smartpad, a wearable device such as a smartwatch or smartglasses, and a computer such as a notebook. The home appliance can include a television, a refrigerator, and a washing machine. The IoT device can include a sensor and a smartmeter.

[0042] 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 broadcasting 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 autonomous driving functionality, 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 5G services, or a device related to the fourth industrial revolution field.

[0043] For example, the UAV can be a flying object that flies by a wireless control signal without a person on board.

[0044] For example, the VR device can include a device for implementing objects or backgrounds of a virtual world. For example, the AR device can include a device implemented by connecting objects or backgrounds of a virtual world to objects or backgrounds of a real world. For example, the MR device can include a device implemented by merging objects or backgrounds of a virtual world into objects or backgrounds of a real world. For example, the hologram device can include a device for implementing a 360-degree stereoscopic image by recording and reproducing stereoscopic information using an optical interference phenomenon generated when two lasers meet, which is called holography.

[0045] For example, the public safety device can include an image relay device or an image device that can be worn on a user's body.

[0046] For example, the MTC device and the IoT device can be devices that do not require 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.

[0047] For example, the medical device can be a device for the purpose of diagnosing, treating, relieving, curing, or preventing a disease. For example, the medical device can be a device for the purpose of diagnosing, treating, relieving, or correcting an injury or a wound. For example, the medical device can be a device for the purpose of inspecting, replacing, or modifying a structure or a function. For example, the medical device can be a device for 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.

[0048] For example, the safety device can be 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.

[0049] For example, the financial technology device can be a device capable of providing a financial service such as mobile payment. For example, the financial technology device can include a payment device or a point of sales (POS) system.

[0050] For example, the weather / environment device can include a device for monitoring or predicting weather / environment.

[0051] 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.

[0052] 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, wireless communication / connections, 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., can be established by various RATs (e.g., 5G NR). 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 for transmitting / receiving radio signals, various signal processing procedures (e.g., channel encoding / decoding, modulation / demodulation, and resource mapping / demapping), and resource allocation procedures can be performed based on various proposals of the disclosure.

[0053] AI refers to a field that studies artificial intelligence or a method that can create it, and machine learning refers to a field that defines various problems solved in the AI field and a field that solves them. Machine learning is also defined as an algorithm that increases the performance of a task through stable experience of the task.

[0054] A robot means a machine that automatically processes or operates a given task by its own ability. In particular, a robot having the ability to recognize an environment and determine an execution action by itself can be referred to as an intelligent robot. The robot can be classified into industrial, medical, home, military, etc. according to a purpose or a field of use. The robot can perform various physical operations, such as moving a robot joint using an actuator or a motor. A movable robot also includes a driven wheel, a brake, a propeller, etc., thereby allowing it to travel on the ground or fly in the air.

[0055] 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 maintaining a lane in motion, automatically adjusting a speed (e.g., adaptive cruise control), automatically driving along a set route, and automatically setting a route when a destination is set. A vehicle encompasses 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 can include a train, a motorcycle, etc., as well as an automobile. An autonomous vehicle can be regarded as a robot having an autonomous driving function.

[0056] Extended reality is collectively referred to as VR, AR, and MR. VR technology provides real-world objects and backgrounds 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 a virtual object into a real world. MR technology is similar to AR technology in that they display a real object and a virtual object together. However, the difference is that, in AR technology, a virtual object is used as a supplementary form of a real object, whereas, in MR technology, a virtual object and a real object are used as equal individuals.

[0057] NR supports multiple numerologies (and / or multiple subcarrier spacings (SCSs)) to support various 5G services. For example, if the SCS is 15 kHz, a wide area can be supported in a legacy cellular band, if the SCS is 30 kHz / 60 kHz, a dense urban, lower latency, and wider carrier bandwidth 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.

[0058] 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 "6 GHz below range," FR2 can mean a "6 GHz above range" and can be referred to as a millimeter wave (mmW).

[0059] [Table 1]

[0060] 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

[0061] As described above, the number of frequency ranges of the NR system can vary. For example, as shown in Table 2 below, FR1 can include frequency bands of 410 MHz to 7125 MHz. That is, FR1 can include a frequency band of 6 GHz (or 5850 MHz, 5900 MHz, 5925 MHz, etc.) or more. For example, the frequency band of 6 GHz (or 5850 MHz, 5900 MHz, 5925 MHz, etc.) or more included in FR1 can include an unlicensed band. The unlicensed band can be used for various purposes, for example, communication for vehicles (e.g., autonomous driving).

[0062] [Table 2]

[0063] 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

[0064] Here, the radio communication technology implemented in the wireless device in the 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 specifications such as LTE Cat NB1 and / or LTE Cat NB2, and can not be limited to the above names. Additionally and / or alternatively, the radio communication technology implemented in the wireless device in the disclosure can be communicated 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 names. Additionally and / or alternatively, the radio communication technology implemented in the wireless device in the disclosure can include at least one of ZigBee, Bluetooth, and / or LPWAN considering low-power communication, and can not be limited to the above names. 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.

[0065] Figure 2 An example of a wireless device to which implementations of the disclosure are applied is illustrated.

[0066] 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).

[0067] In Figure 2 {the first wireless device 100 and the second wireless device 200} can correspond to Figure 1 {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} among at least one of the above.

[0068] The first wireless device 100 can include at least one transceiver (e.g., the transceiver 106), at least one processing chip (e.g., the processing chip 101), and / or one or more antennas 108.

[0069] The processing chip 101 can include at least one processor (e.g., the processor 102) and at least one memory (e.g., the memory 104). Figure 2 The memory 104 is exemplarily shown as being included in the processing chip 101 in the above. Additionally and / or alternatively, the memory 104 can be placed outside of the processing chip 101.

[0070] The processor 102 can control the memory 104 and / or the transceiver 106, and can be configured to implement the descriptions, functions, procedures, suggestions, 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.

[0071] The memory 104 can be operatively connected to the processor 102. The memory 104 can store various types of information and / or instructions. The memory 104 can store software code 105 implementing instructions that, when executed by the processor 102, perform the descriptions, functions, procedures, suggestions, 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, procedures, suggestions, 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.

[0072] In this document, the processor 102 and the memory 104 can be part of a communication modem / circuitry / 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 transceiver 106 can include a transmitter and / or a receiver. The transceiver 106 can be used interchangeably with radio frequency (RF) unit. In this disclosure, the first wireless device 100 can represent a communication modem / circuitry / chip.

[0073] The second wireless device 200 can include at least one transceiver (e.g., the transceiver 206), at least one processing chip (e.g., the processing chip 201), and / or one or more antennas 208.

[0074] The processing chip 201 can include at least one processor (e.g., the processor 202) and at least one memory (e.g., the memory 204). Figure 2 The memory 204 is shown exemplarily as being included in the processing chip 201. Additionally and / or alternatively, the memory 204 can be placed outside the processing chip 201.

[0075] The processor 202 can control the memory 204 and / or the transceiver 206, and can be configured 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.

[0076] 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 implementing 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.

[0077] In this document, the processor 202 and the memory 204 can be a part of a communication modem / circuitry / chip designed to implement 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 transceiver 206 can include a transmitter and / or a receiver. The transceiver 206 can be used interchangeably with an RF unit. In this disclosure, the second wireless device 200 can represent a communication modem / circuitry / chip.

[0078] Hereinafter, the hardware elements of the wireless devices 100 and 200 will be described more specifically. One or more protocol layers can be implemented by one or more processors 102 and 202, but are not limited thereto. 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 operational flowcharts disclosed in the 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 operational flowcharts disclosed in the 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 operational flowcharts disclosed in the 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 operational flowcharts disclosed in the disclosure.

[0079] 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, suggestions, 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, suggestions, 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 to be driven by the one or more processors 102 and 202. The descriptions, functions, processes, suggestions, 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.

[0080] 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 programmable read only memory (EPROM), flash memory, hard disk drive, register, cache memory, computer readable storage media, 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 connection.

[0081] 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.

[0082] 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).

[0083] The one or more transceivers 106 and 206 can convert the 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 the 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 by 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 at a carrier frequency. The one or more transceivers 106 and 206 can receive OFDM signals at a carrier frequency and down-convert the OFDM signals to OFDM baseband signals by their (analog) oscillators and / or filters under the control of the one or more processors 102 and 202.

[0084] 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 the 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, mounted on, or activated in the first wireless device 100 can be configured to perform a UE behavior according to implementations of the disclosure or to control the transceiver 106 to perform a UE behavior according to implementations of the disclosure. The processor 202 connected to, mounted on, or activated in the second wireless device 200 can be configured to perform a BS behavior according to implementations of the disclosure or to control the transceiver 206 to perform a BS behavior according to implementations of the disclosure.

[0085] In the disclosure, the BS is also referred to as a Node B (NB), an eNode B (eNB), or a gNB.

[0086] Figure 3 An example of a wireless device to which implementations of the disclosure are applied is illustrated.

[0087] The wireless device can be variously implemented according to use cases / services (refer to Figure 1 ).

[0088] Refer to Figure 3Wireless devices 100 and 200 can correspond to Figure 2 The wireless devices 100 and 200 are configured with 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 the wireless devices 100 and 200. For example, control unit 120 may control the electromechanical operation of each of the wireless devices 100 and 200 based on programs / code / commands / information stored in memory unit 130. Control unit 120 may transmit information stored in memory unit 130 to an external source (e.g., other communication device) via communication unit 110 through a wireless / wired interface, or store information received from an external source (e.g., other communication device) via wireless / wired interface in memory unit 130 via communication unit 110.

[0089] The additional component 140 may be configured differently depending on the type of wireless devices 100 and 200. For example, the additional 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 may be configured according to the type of robot (…). 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 / environmental devices, AI servers / devices ( Figure 1 400), BS ( Figure 1 Wireless devices 100 and 200 can be implemented in the form of network nodes, etc., but are not limited to this. Depending on the use case / service, wireless devices 100 and 200 can be used in mobile or fixed locations.

[0090] In Figure 3 , various elements, components, units / portions, and / or modules in the wireless devices 100 and 200 can all be connected to each other through wired interfaces, or at least some of them can be wirelessly connected through the communication units 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 wires, and the control unit 120 and the first units (e.g., 130 and 140) can be wirelessly connected through the communication unit 110. The various elements, components, units / portions, and / or modules within the wireless devices 100 and 200 can also 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, DRAM, ROM, flash memory, volatile memory, non-volatile memory, and / or a combination thereof.

[0091] Figure 4 An example of a UE to which implementations of the present disclosure is applied is illustrated.

[0092] Referring to Figure 4 , the UE 100 can correspond to the first wireless device 100 of Figure 2 , and / or the wireless device 100 or 200 of Figure 3 .

[0093] 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.

[0094] The processor 102 can be configured to implement the 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 the 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 chip sets, logic circuits, and / or data processing devices. 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 found in Snapdragon TM series processors manufactured by Qualcomm®, manufactured by samsung TM series of processors, manufactured by samsung manufactured by samsung TM series of processors, manufactured by samsung TM series of processors or corresponding next generation processor.

[0095] The memory 104 is operatively coupled with the processor 102 and stores various information to operate the processor 102. The memory 104 can include ROM, RAM, flash memory, a memory card, a storage medium and / or other storage devices. When the embodiments are implemented in software, the techniques described herein can be implemented with modules (e.g., procedures, functions, and so on) that perform the description, functions, procedures, suggestions, methods and / or operational flow disclosed in this 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 those can be communicatively coupled to the processor 102 via various means as is known in the art.

[0096] The transceiver 106 is operatively coupled with the processor 102 and transmits and / or receives radio signals. The transceiver 106 includes a transmitter and a receiver. The transceiver 106 can include a baseband circuit to process radio frequency signals. The transceiver 106 controls one or more antennas 108 to transmit and / or receive radio signals.

[0097] 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.

[0098] The display 114 outputs results of processing by the processor 102. The keypad 116 receives input to be used by the processor 102. The keypad 116 can be displayed on the display 114.

[0099] The SIM card 118 is an integrated circuit that is 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.

[0100] 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.

[0101] <Redundant PDU Session>

[0102] To support high-reliability URLLC (Ultra-Reliable and Low-Latency Communication) services, a terminal can establish two redundant PDU sessions via a 5G network. It can be used for applications that require reliability. The two PDU sessions can be established and managed by different network nodes. The same data can be sent through the two PDU sessions.

[0103] The 5GS can establish the user plane paths of the two redundant PDU sessions to be disjoint. The user's subscription indicates whether the user is allowed to have redundant PDU sessions, and this indication can be provided from the UDM to the SMF.

[0104] The RAN supports dual connectivity, and there can be sufficient RAN coverage in the target area for dual connectivity. The UE can support dual connectivity. The core network UPF deployment can align with the RAN deployment, and can support redundant user plane paths. The underlying transport topology can align with the RAN and UPF deployment, and can support redundant user plane paths. The geographical distribution of physical network topology and functions can also support redundant user plane paths, to the extent deemed necessary by the operator. The operation of the redundant user plane paths can be conducted sufficiently independently, to the extent deemed necessary by the operator.

[0105] Figure 5 An example is shown of redundant user plane paths using dual connectivity.

[0106] Figure 5 An example user plane resource configuration of dual PDU sessions when redundancy is applied is shown. One PDU session traverses from the UE via a primary NG-RAN to UPF1 acting as a PDU session anchor, and the other PDU session traverses from the UE via a secondary NG-RAN to UPF2 acting as a PDU session anchor. The NG-RAN can implement redundant user plane resources for the two PDU sessions with two NG-RAN nodes (i.e., primary and secondary NG-RAN) or a single NG-RAN node. In both cases, there is a single N1 interface towards the AMF.

[0107] Based on the two PDU sessions, two independent user plane paths can be established. UPF1 and UPF2 are connected to the same data network (DN), although traffic via UPF1 and UPF2 can be routed via different user plane nodes within the DN.

[0108] To establish the two redundant PDU sessions and associate the duplicated traffic from the same application to these PDU sessions, URSP or UE local configuration can be used.

[0109] With URSP, duplicated traffic from an application associated to a redundant PDU session is distinguished by two different traffic descriptors, each in a different URSP rule. These traffic descriptors need to have different DNN, IP descriptor or non-IP descriptor (e.g. MAC address, VLAN ID) so that the two redundant PDU sessions are matched to different routing descriptors of the URSP rules.

[0110] Redundant user plane establishment can be applied to both IP and Ethernet PDU sessions.

[0111] Support of redundant PDU sessions includes:

[0112] - A UE can initiate two redundant PDU sessions and can be provided with different combinations of DNN and S-NSSAI for each PDU session.

[0113] - An SMF can determine if a PDU session is to be handled redundantly. If dynamic PCC (Policy and Charging Control) applies to the PDU session, the determination is based on an indication provided by the PCF for the PDU session that a redundant PDU session is needed, or if dynamic PCC is not used for the PDU session, the determination is based on a combination of S-NSSAI, DNN, user subscription and local policy configuration in the SMF. If the PDU session is to be handled redundantly, the SMF uses the S-NSSAI, DNN to determine an RSN value that distinguishes the redundantly handled PDU session and indicates the redundant user plane requirement of the PDU session in the NG-RAN.

[0114] - Operator configuration of UPF selection can ensure proper UPF selection of disjoint paths.

[0115] - At PDU session establishment or at transition to CM-CONNECTED state, an RSN parameter can indicate to the NG-RAN that redundant user plane resources should be provided for a given PDU session through dual connectivity. The value of the RSN parameter can indicate the redundant user plane requirement of the PDU session. This request for redundant handling can be done by indicating the RSN to the NG-RAN node at per PDU session granularity. PDU sessions associated with different RSN values should be implemented by different redundant UP resources. Based on the RSN and RAN configuration, the NG-RAN establishes dual connectivity so that the session has end-to-end redundant paths. When there are multiple PDU sessions with a set of RSN parameters and with different RSN values, this indicates to the NG-RAN that the CN requests to establish dual connectivity and the user plane should be handled as indicated by the RSN parameters and associated RAN configuration. If an RSN value is provided to the NG-RAN, the NG-RAN should take the RSN value into account when associating the PDU session with the NG-RAN UP.

[0116] The decision to establish dual connectivity can be left in NG-RAN. NG-RAN can consider additional request for dual connectivity establishment provided by CN.

[0117] - Using NG-RAN local configuration, NG-RAN can determine whether to meet the request for PDU session establishment of RAN resource by considering the user plane requirement indicated by RSN parameter for dual connectivity. If RAN can meet the request for PDU session establishment of RAN resource, the PDU session can be established even if the user plane requirement indicated by RSN cannot be met. If NG-RAN determines that the request for establishment of RAN resource cannot be met, it should reject the request, which eventually triggers SMF to reject PDU session establishment towards the UE. The decision for individual PDU session can be made independently. That is, the rejection of PDU session request should not release the previously established PDU session. RAN should determine whether to inform SMF whether the RAN resource indicated by RSN parameter can no longer be maintained, and SMF can use it to determine whether the PDU session should be released.

[0118] - In the case of Ethernet PDU session, SMF has the possibility to change the UPF (acting as PSA) and modify (or add / release) secondary NG-RAN using Ethernet PDU session anchor relocation procedure.

[0119] - The charging record of SMF can reflect RSN information.

[0120] - RSN indication is transferred from source NG-RAN to target NG-RAN in case of handover.

[0121] UE Route Selection Policy (URSP) will be described.

[0122] When user data traffic is generated in the UE, which PDU session to send it can be determined by URSP of the UE. URSP can include one or more URSP rules according to the action of traffic indication request. Each URSP rule can consist of rule precedence, traffic descriptor (TD) corresponding to rule criteria, and route selection descriptor (RSD) corresponding to the action according to each URSP rule, etc.

[0123] (1) Rule precedence

[0124] The order in which URSP rules are enforced in the UE is determined. That is, rule precedence identifies the priority of URSP rules among all existing URSP rules. Each URSP rule within URSP has a different priority value.

[0125] (2) Traffic descriptor

[0126] Each URSP rule contains a TD that determines when the URSP rule is applied. The TD includes one or more components that will be described below. A URSP rule is determined to be applied when all elements in the TD match the corresponding information from the application. In the following cases, a URSP rule is determined not to be applied for a given element within the TD:

[0127] - when the corresponding information from the application is not available; or

[0128] - when the corresponding information from the application does not match the value of the TD component.

[0129] If URSP rules containing TDs with more than one component are provided, it is recommended to provide URSP rules with lower priority and TDs with fewer components to increase the likelihood of a particular application matching a URSP rule.

[0130] The TD includes any of the following:

[0131] 1) match all traffic descriptors; or

[0132] 2) at least one of the following components:

[0133] a) one or more application IDs;

[0134] b) one or more IP 3-tuples, i.e., destination IP address, destination port number, and protocol used over IP;

[0135] c) one or more non-IP descriptors, i.e., destination of non-IP traffic;

[0136] d) one or more DNNs;

[0137] e) one or more connection capabilities; and

[0138] f) one or more domain descriptors, i.e., target fully qualified domain name (FQDN);

[0139] (3) one or more RSDs;

[0140] Each URSP rule contains a list of RSDs that contains one or more RSDs. Each RSD has a different RSD priority value. An RSD includes one or more of the following components:

[0141] - SSC (Session and Service Continuity) mode: indicates that the matching application traffic should be routed through a PDU session that supports the included SSC mode.

[0142] - Network Slice Selection: indicates that the traffic matching the application should be routed over a PDU Session that supports the S-NSSAI. Contains one or more S-NSSAI.

[0143] - DNN Selection: indicates that the traffic matching the application should be routed over a PDU Session that supports the DNN. Contains one or more DNN. When DNN is used in TD, the RSD of the corresponding URSP rule does not include the DNN Selection component.

[0144] - PDU Session Type Selection: indicates that the traffic matching the application should be routed over a PDU Session that supports the PDU Session Type.

[0145] - Non-smooth offload indication: indicates that the traffic matching the application when the URSP rule is applied is offloaded to a non-3GPP connection outside the PDU Session. If this element is in the RSD, other elements are not included in the RSD.

[0146] - Access Type Preference: indicates the type of connection (3GPP or non-3GPP or multi-access) that the PDU Session should be established when the UE needs to establish a PDU Session when the URSP rule is applied. Multi-access type indicates that the PDU Session should be established as a MA PDU Session that uses both 3GPP access and non-3GPP access.

[0147] - Time Window: the RSD is considered invalid if the UE is not within the time window.

[0148] - Location Criteria: the RSD is considered invalid if the location of the UE does not match the location criteria.

[0149] Table 3 shows an example of RSD.

[0150] [Table 3]

[0151]

[0152] If the PDU Session Establishment Request is rejected by the network, the UE can trigger a new PDU Session Establishment based on the rejection cause and the URSP policy. When the PCF provides URSP rules to the UE, one URSP rule with the "match-all" TD can be included.

[0153] The URSP rule with the "match-all" TD is used to route the traffic of applications that do not match any other URSP rule, and therefore is evaluated as the last URSP rule, i.e., the URSP rule with the lowest priority. There is only one RSD in this URSP rule. The RSD of this URSP rule contains at most one value for each path selection component.

[0154] In URSP, only one URSP rule can be a default URSP rule, and all default URSP rules include a matching TD. If a default URSP rule and one or more non-default URSP rules are included in the URSP, any non-default URSP rule shall have a lower precedence value than the default URSP rule (i.e., shall take precedence over the default URSP rule).

[0155] If the traffic descriptor lists one or more application identifiers and one or more connection capabilities, the UE shall consider the application identifiers to identify applications that request access to the connection capabilities.

[0156] If one or more DNNs are included in the traffic descriptor of a URSP rule, the routing selection descriptor of the URSP rule shall not include any DNN.

[0157] A PCF of a home public land mobile network (HPLMN) can provide URSP rules to a UE. When the UE is roaming, the PCF of the HPLMN can update the URSP rules of the UE. For URSP rules, the UE supports provisioning from the PCF of the HPLMN. In addition, the UE can be pre-configured with URSP rules (e.g., by an operator).

[0158] If both URSP rules provisioned by the PCF and pre-configured URSP rules are present, the UE uses only the URSP rules provisioned by the PCF. If no URSP rules are provisioned by the PCF and the UE is pre-configured with URSP rules in both the universal subscriber identity module (USIM) and the mobile equipment (ME), only the pre-configured URSP rules in the USIM are used.

[0159] For each newly detected application, the UE evaluates the URSP rules in order of rule precedence and determines which URSP rule’s TD the application matches.

[0160] If a URSP rule is determined to be applicable for a particular application, the UE selects an RSD within this URSP rule in order of RSD precedence.

[0161] If a valid RSD is found, the UE checks if there is an existing PDU session that matches all the elements of the selected RSD. The UE compares the components of the selected RSD with existing PDU sessions as follows.

[0162] - For a component that contains only one value (e.g., SSC mode), the value of the PDU session must be the same as the value specified in the routing selection descriptor.

[0163] - For a component that contains a list of values (e.g., network slice selection), the value of the PDU session must be the same as one of the values specified in the routing selection descriptor.

[0164] - When some components are not present in the routing descriptor, a PDU session is considered to match only if it is established without the missing components in the PDU session establishment request.

[0165] - When the routing descriptor includes a time window or a location criterion, a PDU session is considered to match only if it is associated with a RSD with the same time window or location criterion validity condition.

[0166] When a matching PDU session exists, the UE shall apply the association to the existing PDU session, i.e. route the detected application's traffic on that PDU session.

[0167] If no existing PDU session matches, the UE attempts to establish a new PDU session using the values specified by the selected routing descriptor. If the PDU session establishment request is accepted, the UE shall apply the association to the new PDU session. If the PDU session establishment request is rejected, based on the rejection cause, the UE selects another combination of values in the currently selected routing descriptor if any other value of the same component used for rejection in the routing descriptor can be used. Otherwise, the UE selects the next routing descriptor (if any) containing a combination of component values not rejected by the network in the routing descriptor priority order. If the UE fails to establish a PDU session with any routing descriptor, it attempts other URSP rules (if any) in the priority order of rules with matching traffic descriptors except for URSP rules with "match-all" traffic descriptor. In this case, the UE shall not use UE local configuration.

[0168] The UE receives updated URSP rules and (re-)evaluates their validity when certain conditions are met, e.g.:

[0169] - the URSP is updated by the PCF;

[0170] - the UE moves from EPC to 5GC;

[0171] - the allowed NSSAI or configured NSSAI changes;

[0172] - the LADN DNN availability changes;

[0173] - the UE registers via 3GPP or non-3GPP access;

[0174] - the UE establishes a connection to WLAN access.

[0175] A routing descriptor of a URSP rule shall be considered valid only if all the following conditions are met:

[0176] - If there is any S-NSSAI, for non-roaming case, the S-NSSAI is in the allowed NSSAI, for roaming case, in the mapping of the allowed NSSAI to HPLMN S-NSSAI.

[0177] - If there is any DNN and the DNN is a LADN DNN, the UE is within the availability area of the LADN.

[0178] - If there is an access type preference and it is set to multi-access, the UE supports ATSSS.

[0179] - If there is a time window and the time matches what is indicated in the time window.

[0180] - If there is a location criterion and the UE location matches what is indicated in the location criterion.

[0181] If a URSP rule does not have a valid RSD, the UE attempts other URSP rules in the order of precedence of rules with matching traffic descriptors, except for URSP rules with "match-all" traffic descriptor.

[0182] When a URSP rule is updated or its validity according to the above conditions changes, it can be necessary to re-evaluate the existing association of applications to PDU sessions. The UE can also re-evaluate the association of applications to PDU sessions due to:

[0183] - Periodic re-evaluation based on UE implementation;

[0184] - Existing PDU session used for routing traffic of an application based on URSP rules is released;

[0185] - Time window in the routing selection verification criterion expires (i.e., time window expires), or the UE's location no longer matches the location criterion.

[0186] If the re-evaluation results in a change of the association of an application to a PDU session, e.g., the application is to be associated with another PDU session or a new PDU session needs to be established, the UE can enforce these changes based on implementation in time (e.g., immediately or when the UE enters CM-IDLE state).

[0187] If the selected routing descriptor contains a non-seamless offload indication and the UE has established a connection to WLAN access, the UE routes the traffic matching the traffic descriptor of the URSP rule via WLAN access outside the PDU session.

[0188] Table 4 shows an example of URSP rules.

[0189] [Table 4]

[0190]

[0191]

[0192]

[0193] <Problem to be solved by the disclosure of this specification>

[0194] For redundant transmission, the UE can send a PDU session pair ID paired with a PDU session to the SMF. Then, the SMF can forward this information to the NG-RAN along with the RSN parameter. Based on this information, the NG-RAN can provide separate user plane resources for two redundant PDU sessions.

[0195] In addition, to clarify how the UE obtains the knowledge of PDU session pair information for redundant PDU sessions, when the UE accesses a network (Rel-17) that supports PDU session pair ID, the PCF can provide the UE with a URSP rule including a PDU session pair ID for redundant transmission.

[0196] According to this URSP rule, the UE can start two redundant PDU sessions and can include a PDU session pair ID so that the network can pair redundant PDU sessions.

[0197] However, the PCF does not know whether the UE supports the PDU session pair ID. If a Rel-16 UE that supports only Rel-16 URLLC accesses a Rel-17 network that supports the PDU session pair ID, the Rel-16 UE can be configured with a URSP rule including the PDU session pair ID. In this case, the UE cannot recognize the PDU session pair ID in the URSP rule. If the RSD (Route Selection Descriptor) of the URSP rule includes a component that the UE cannot recognize, the corresponding RSD must be skipped. Therefore, if the PCF configures the UE with a URSP rule having a PDU session pair ID for redundant transmission, the UE cannot start two redundant PDU sessions.

[0198] <Disclosure of the specification>

[0199] Some of the steps in the following procedures can be performed simultaneously or in parallel, or in reverse order.

[0200] The following drawings are used to explain specific examples of the present specification. Since the names of specific devices described in the drawings or the names of specific signals / messages / fields are provided as examples, the technical features of the present specification are not limited to the specific names used in the following drawings.

[0201] 1. First Embodiment

[0202] The UE can indicate to the PCF whether PDU session pair ID is supported during the registration procedure. Based on the indication, the PCF can determine whether to establish URSP including PDU session pair ID in the UE.

[0203] Figure 6 A first example of the first embodiment of the present specification is shown.

[0204] (1) Step 1: The UE can send a registration request message to the AMF over the NG-RAN to register in the network.

[0205] The UE can initiate a registration procedure by sending a registration request message to the AMF over the NG-RAN to register with the network.

[0206] The UE can include an indication of whether the UE supports PDU session pair ID in the UE policy container IE of the registration request message.

[0207] (2) Step 2: Steps 4 to 21 of TS 23.502 V17.0.0 Figure 4 .2.2.2.2-1d can be performed.

[0208] (3) Step 3: The AMF can send a UE policy association establishment message to the PCF.

[0209] The AMF can include an indication of whether the UE supports PDU session pair ID in the UE policy association establishment message and transfer it to the PCF.

[0210] (4) Step 4: The PCF can update the URSP rule.

[0211] If the indication of whether the UE supports PDU session pair ID is included in the UE policy association establishment message, the PCF can determine to configure the URSP rule including "PDU session pair ID" in the UE. If the indication is not included, the PCF can configure the URSP rule without PDU session pair ID to the UE.

[0212] Note: Alternatively, if the UE's support indication is included, the PCF can only configure the RSD including "PDU session pair ID" in the URSP rule to the UE. If the indication is not included, the PCF can configure the RSD not including PDU session pair ID in the URSP rule to the UE.

[0213] (5) Step 5: The PCF can send a UE configuration update message to the UE.

[0214] The UE configuration update message can include the updated URSP rule. The route selection descriptor (RSD) of the URSP rule can include the PDU session pair ID.

[0215] The PCF can send the updated URSP rules to the UE through a configuration update procedure. According to the URSP rules, the UE can initiate two redundant PDU sessions. If the PDU session pair ID is included in the URSP rules, the UE can include and send the PDU session pair ID in the PDU session establishment request message.

[0216] NOTE: Regardless of the UE support indication for “PDU session pair ID”, the PCF can determine and provide two types of URSP rules with or without PDU session pair ID to the UE. In this case, even if the UE supporting only Rel-16 URLLC accesses the Rel-17 network supporting PDU session pair ID, the UE can initiate two redundant PDU sessions based on the URSP rules without PDU session pair ID from the PCF.

[0217] NOTE: Alternatively, regardless of the UE support indication for “PDU session pair ID”, the PCF can also provide the UE with the route selection descriptor containing the same components except for the PDU session pair ID. In other words, the PCF determines and can provide the UE with two types of RSDs in the URSP rules with or without PDU session pair ID (i.e., two RSDs of the same traffic descriptor). It is noted that the route selection descriptor with PDU session pair ID has a lower precedence than the route selection descriptor without PDU session pair ID. In this case, even if the UE supporting only Rel-16 URLLC accesses the Rel-17 network supporting PDU session pair ID, the UE can initiate two redundant PDU sessions based on the route selection descriptor without PDU session pair ID in the URSP rules from the PCF.

[0218] Figure 7 and Figure 8 A second example of the first embodiment of the present specification is shown.

[0219] Figure 7 and Figure 8 The first embodiment of the present specification is applied to an initial registration procedure.

[0220] A UE must register with the network to receive services, enable mobility tracking, and enable reachability. The UE initiates the registration procedure using one of the following registration types.

[0221] - Initial registration of the 5GS; or

[0222] - Mobility registration update; or

[0223] - Periodic registration update; or

[0224] - Emergency registration

[0225] Figure 7 andThe general registration procedure of Figure 8 applies to all the registration procedures described above, but the regular registration update does not need to include all the parameters used in the other registration procedures.

[0226] When the UE has registered a non-3GPP connection, the Figure 7 and Figure 8 general registration procedures are also used when the UE registers a 3GPP connection, and vice versa. When the UE has registered a non-3GPP access scenario, the AMF change can be needed to register a 3GPP connection.

[0227] First, the procedure of Figure 7 will be described.

[0228] (1) Step 1: The UE can send a Registration Request message to the (R)AN. The Registration Request message can correspond to the AN message.

[0229] The Registration Request message can include AN parameters. In the case of NG-RAN, the AN parameters can include, for example, a 5G-S-TMSI (5G SAE Temporary Mobile Subscriber Identity) or a GUAMI (Global Unique AMF ID), a selected PLMN (Public Land Mobile Network) ID (or PLMN ID and NID (Network Identifier)), and a requested NSSAI (Network Slice Selection Assistance Information). The AN parameters can also include an establishment cause. The establishment cause can include a cause for requesting establishment of an RRC connection. Whether and how the UE includes the requested NSSAI as part of the AN parameters can depend on the value of the access stratum connection establishment NSSAI inclusion mode parameter.

[0230] The Registration Request message can include a registration type. The registration type indicates whether the UE wants to perform an initial registration (i.e., the UE is in the RM-DEREGISTERED state), or whether it wants to perform a mobility registration update (i.e., the UE is in the RM-REGISTERED state and initiates the registration procedure due to mobility or due to the UE needing to update its capabilities or protocol parameters or requesting a change of the set of network slices it is allowed to use), or whether it wants to perform a periodic registration update (i.e., the UE is in the RM-REGISTERED state and initiates the registration procedure due to expiry of the periodic registration update timer), or whether it wants to perform an emergency registration (i.e., the UE is in the limited service state).

[0231] When the UE is performing an initial registration, the UE can indicate its UE identity in the Registration Request message as follows, listed in descending order of preference in case of registration with a PLMN.

[0232] i) If the UE has a valid EPS GUTI, the 5G-GUTI mapped from the EPS GUTI.

[0233] ii) a locally assigned 5G-GUTI of the PLMN the UE is attempting to register with (if available);

[0234] iii) a locally assigned 5G-GUTI of the PLMN the UE is attempting to register with assigned by an equivalent PLMN (if available);

[0235] iv) a locally assigned 5G-GUTI of any other PLMN (if available).

[0236] This can also be a 5G-GUTI assigned via another access type.

[0237] v) Otherwise, the UE can include its SUCI (Subscriber Concealed Identifier) in the registration request.

[0238] When a UE performing initial registration has both a valid EPS GUTI and a locally assigned 5G-GUTI, the UE can also indicate the locally assigned 5G-GUTI as an additional GUTI. If more than one locally assigned 5G-GUTI is available, the UE can select the 5G-GUTI in a descending order of preference among items (ii)-(iv) in the above list.

[0239] When registering with a SNPN with a 5G-GUTI as UE identity, the UE can only use a 5G-GUTI previously assigned by the same SNPN.

[0240] If the UE is sending a registration request message as an initial NAS message and the UE has a valid 5G NAS security context and the UE needs to send non-cleartext IEs, the NAS message container can be included. If the UE does not need to send non-cleartext IEs, the UE can need to send the registration request message without including the NAS message container.

[0241] If the UE does not have a valid 5G NAS security context, the UE can need to send the registration request message without including the NAS message container. The UE can need to include the entire registration request message (i.e., containing cleartext IEs and non-cleartext IEs) in the NAS message container sent as part of the security mode complete message in step 9b.

[0242] When the UE is performing initial registration with a locally assigned 5G-GUTI, the UE can indicate the relevant GUAMI information in the AN parameters. When the UE is performing initial registration with its SUCI, the UE can not indicate any GUAMI information in the AN parameters.

[0243] When the UE is performing initial registration or mobility registration and if CIoT 5GS optimization is supported, the UE can indicate its preferred network behavior. If S1 mode is supported, the EPC preferred network behavior of the UE is included in the S1 UE network capabilities in the registration request message.

[0244] For emergency registration, SUCI shall be included if UE has no valid 5G-GUTI available; PEI can be included when UE has no SUPI and valid 5G-GUTI. In other cases, 5G-GUTI is included and the last serving AMF is indicated.

[0245] The UE can provide the UE's usage setting. The UE provides the requested NSSAI and, in case of initial registration or mobility registration update, the UE includes the requested NSSAI mapping of individual S-NSSAIs to HPLMN S-NSSAI if available, to ensure that the network can verify whether the S-NSSAI in the requested NSSAI is allowed based on the subscribed S-NSSAI. In case of inter-PLMN mobility, if the serving PLMN S-NSSAI corresponding to the established PDU session does not exist in the UE, the associated HPLMN S-NSSAI associated with the established PDU session can be provided in the requested NSSAI mapping.

[0246] If the UE is using the default configured NSSAI, the UE includes the default configured NSSAI indication.

[0247] If the support of WUS assistance information assignment from the AMF is supported, the UE can include the UE paging probability information.

[0248] In case of mobility registration update, the UE includes the PDU sessions for which there is pending uplink data in the list of PDU sessions to be activated. When the UE includes the list of PDU sessions to be activated, the UE can indicate PDU sessions associated with access only related to the registration request. The UE can include in the list of PDU sessions to be activated the always-on PDU sessions accepted by the network even though those PDU sessions do not have pending uplink data.

[0249] NOTE 3: When the UE is outside the available area of a LADN, the PDU session corresponding to the LADN is not included in the list of PDU sessions to be activated.

[0250] The UE MM core network capabilities can be provided by the UE and processed by the AMF. The UE can include in the UE MM core network capabilities an indication of whether the UE supports the request type flag "handover" for PDN connectivity request during the attach procedure. If the UE supports "strict periodic registration timer indication", the UE can indicate its capability "strict periodic registration timer indication" in the UE MM core network capabilities. If the UE supports CAG, the UE can indicate its capability "support CAG" in the UE MM core network capabilities.

[0251] The UE can provide the LADN DNN or the request LADN information indication.

[0252] If available, the last visited TAI can be included to help the AMF generate the registration area for the UE.

[0253] The registration request message can also include security parameters and PDU session status, etc. The security parameters are used for authentication and integrity protection. The PDU session status indicates previously established PDU sessions in the UE. When the UE is connected to two AMFs belonging to different PLMNs via 3GPP access and non-3GPP access, then the PDU session status can indicate the established PDU sessions for the current PLMN in the UE.

[0254] The subsequent request can be included when the UE has pending uplink signaling and the UE does not include the list of PDU sessions to be activated, or the registration type indicates that the UE wants to perform an emergency registration. In the initial registration and mobility registration update, the UE can provide the UE requested DRX parameters. The UE can provide the extended idle mode DRX parameters to request the extended idle mode DRX.

[0255] The UE can provide the UE radio capability update indication.

[0256] If the UE wants to use the MICO mode with an active time, the UE can include the MICO mode preference and optionally request the active time value.

[0257] The UE can indicate its service gap control capability in the UE MM core network capability.

[0258] For a UE with a running service gap timer in the UE, the UE can not set the subsequent request indication or the uplink data status in the registration request message except for network access for regulatory priority services like emergency services or exception reporting.

[0259] If the UE supports RACS and has been assigned a UE radio capability ID, the UE can indicate the UE radio capability ID as a non-plain IE.

[0260] The PEI can be retrieved from the UE in the initial registration.

[0261] The registration request message can include an indication of whether the UE supports PDU session to ID.

[0262] (2) Step 2: The (R)AN can select an AMF.

[0263] If the 5G-S-TMSI or GUAMI is not included or the 5G-S-TMSI or GUAMI does not indicate a valid AMF, the (R)AN can select an AMF based on the (R)AT and the requested NSSAI, if available.

[0264] If the UE is in CM-CONNECTED state, the (R)AN can forward the registration request message to the AMF based on the UE's N2 connection.

[0265] If the (R)AN is unable to select a proper AMF, it forwards the registration request message to an AMF configured in the (R)AN to perform AMF selection.

[0266] (3) Step 3: The (R)AN sends the registration request message to the new AMF. The registration request message corresponds to the N2 message.

[0267] The registration request message can include the entire information and / or partial information included in the registration request message received from the UE in step 1.

[0268] The registration request message can include N2 parameters. When NG-RAN is used, the N2 parameters include the selected PLMN ID (or PLMN ID and NID), location information and cell identity related to the cell in which the UE is camped, and UE context request indicating that a UE context including security information needs to be established at the NG-RAN. When NG-RAN is used, the N2 parameters should also include the establishment cause.

[0269] If the registration type indicated by the UE is periodic registration update, steps 4 to 19 can be omitted.

[0270] (4) Step 4: If the 5G-GUTI of the UE is included in the registration request message and the serving AMF has changed since the last registration procedure, the new AMF can invoke the Namf_Communication_UEContextTransfer service operation on the old AMF including the full registration request Non-Access Stratum (NAS) message to request the SUPI and UE context of the UE.

[0271] (5) Step 5: The old AMF can respond to the Namf_Communication_UEContextTransfer invocation by the new AMF by including the SUPI and UE context of the UE.

[0272] (6) Step 6: If the SUCI is neither provided by the UE nor retrieved from the old AMF, the identity request procedure can be initiated by the new AMF by sending an identity request message to the UE requesting the SUCI.

[0273] (7) Step 7: The UE can respond with an identity response message including the SUCI. The UE derives the SUCI using the public key of the home PLMN (HPLMN) provided.

[0274] (8) Step 8: The new AMF can decide to initiate UE authentication by invoking AUSF. In this case, the new AMF selects the AUSF based on SUPI or SUCI.

[0275] (9) Step 9: Authentication / security can be established by the UE, new AMF, AUSF, and / or UDM.

[0276] (10) Step 10: If the AMF has changed, the new AMF can notify the old AMF of the completion of the registration of the UE in the new AMF by invoking the Namf_Communication_RegistrationCompleteNotify service operation. If the authentication / security procedure fails, the registration should be rejected and the new AMF can invoke the Namf_Communication_RegistrationCompleteNotify service operation towards the old AMF with a reject indication cause code. The old AMF can continue as if it never received the UE Context Transfer service operation.

[0277] (11) Step 11: If the PEI is neither provided by the UE nor retrieved from the old AMF, the new AMF can initiate the identity request procedure by sending an identity request message to the UE to retrieve the PEI. The PEI should be transferred encrypted unless the UE performs an emergency registration and is unable to be aware.

[0278] (12) Step 12: Optionally, the new AMF can initiate the ME identity check by invoking the N5g-eir_EquipmentIdentityCheck_Get service operation.

[0279] Now, the procedure of Figure 6 after the procedure of Figure 7 is described.

[0280] (13) Step 13: If step 14 below is to be performed, based on the SUPI, the new AMF can select the UDM, and then the UDM can select the UDR instance.

[0281] (14) Step 14: The new AMF can register with the UDM.

[0282] (15) Step 15: The new AMF can select the PCF.

[0283] (16) Step 16: The new AMF can optionally perform AM policy association establishment / modification.

[0284] (17) Step 17: The new AMF can send an Update / Release SM Context message (e.g., Nsmf_PDUSession_UpdateSMContext and / or Nsmf_PDUSession_ReleaseSMContext) to the SMF.

[0285] (18) Step 18: If the new AMF and the old AMF are in the same PLMN, the new AMF can send a UE Context Modification Request to the N3IWF / TNGF / W-AGF.

[0286] (19) Step 19: The N3IWF / TNGF / W-AGF can send a UE Context Modification Response to the new AMF.

[0287] (20) Step 20: After the new AMF receives the response message from the N3IWF / TNGF / W-AGF in step 19, the new AMF can register to the UDM.

[0288] (21) Step 21: The new AMF sends a Registration Accept message to the UE.

[0289] The new AMF sends a Registration Accept message to the UE indicating that the Registration Request has been accepted. If the new 5G-GUTI is allocated by the new AMF, it is included. If the UE is already in the RM-REGISTERED state via another access in the same PLMN, the UE shall use the 5G-GUTI received in the Registration Accept message for both registrations. If the 5G-GUTI is not included in the Registration Accept message, the UE shall use the 5G-GUTI assigned for the existing registration for the new registration as well. If a new registration area is allocated by the new AMF, it shall send the registration area to the UE via the Registration Accept message. If the registration area is not included in the Registration Accept message, the UE shall consider the old registration area valid. The mobility registration is included in case mobility restrictions apply to the UE and the registration type is not an emergency registration. The new AMF indicates the established PDU Sessions to the UE in PDU Session Status. The UE locally removes any internal resources related to PDU Sessions that are not marked as established in the received PDU Session Status. When the UE is connected to two AMFs belonging to different PLMNs via 3GPP access and non-3GPP access, the UE locally removes any internal resources related to PDU Sessions that are not marked as established in the received PDU Session Status for the current PLMN. If the PDU Session Status information is in the Registration Request message, the new AMF shall indicate the PDU Session Status to the UE.

[0290] The allowed NSSAI provided in the registration accept message is valid in the registration area and applies to all PLMNs whose tracking areas are included in the registration area. The allowed NSSAI mapping is the mapping of individual S-NSSAIs of the allowed NSSAI to HPLMN S-NSSAIs. The configured NSSAI mapping is the mapping of individual S-NSSAIs of the configured NSSAI of the serving PLMN to HPLMN S-NSSAIs.

[0291] Further, optionally, the new AMF performs UE policy association establishment.

[0292] (22) Step 22: When successfully updating itself, the UE can send a registration complete message to the new AMF.

[0293] The UE can send a registration complete message to the new AMF to confirm whether a new 5G-GUTI is assigned.

[0294] (23) Step 23: For registration via 3GPP access, if the new AMF does not release the signaling connection, the new AMF can send RRC Inactive Assistance Information to the NG-RAN. For registration via non-3GPP access, if the UE is also in CM-CONNECTED state on 3GPP access, the new AMF can send RRC Inactive Assistance Information to the NG-RAN.

[0295] (24) Step 24: The new AMF can perform information update towards the UDM.

[0296] (25) Step 25: The UE can perform network slice specific authentication and authorization procedures.

[0297] 2. Second embodiment

[0298] Regardless of whether the UE sends an indication of whether the UE supports PDU session-to-ID, the PCF can create two URSP rules with and without PDU session-to-ID and can provide them to the UE. In this case, even if a UE supporting only Rel-16 URLLC (a UE not supporting PDU session-to-ID) accesses a Rel-17 network supporting PDU session-to-ID, the UE can initiate two redundant PDU sessions based on the URSP rule without PDU session-to-ID from the PCF.

[0299] The PCF can provide the UE with an RSD including the same components except for the PDU session pair ID. For the same service descriptor, the PCF can create a URSP rule containing two RSDs. One of the two RSDs can be an RSD with a PDU session pair ID, and the other RSD can be an RSD without a PDU session pair ID. The PCF can set the priority so that the RSD with the PDU session pair ID is selected before the RSD without the PDU session pair ID. The URSP rule thus determined can be transmitted to the UE. Depending on the type of the UE, two redundant PDU sessions can be created as follows.

[0300] 1) In the case of a UE that does not support a PDU session pair ID

[0301] The UE first checks the RSD including the PDU session pair ID with higher priority, but since the UE cannot recognize the PDU session pair ID, the UE can skip the corresponding RSD. Then, the UE checks the RSD not including the PDU session pair ID with lower priority, and thus can create two redundant PDU sessions based on the RSD not including the PDU session pair ID.

[0302] 2) In the case of a UE that supports a PDU session pair ID

[0303] The UE first checks the RSD including the PDU session pair ID with higher priority, and since the UE can recognize the PDU session pair ID, the UE can create two redundant PDU sessions based on the corresponding RSD.

[0304] 3. Third embodiment

[0305] Figure 9 、 Figure 10 、 Figure 11 and Figure 12 An example of the third embodiment of the present specification is shown.

[0306] The UE in the CM IDLE state can initiate a service request procedure by transmitting an uplink signaling message or user data, requesting emergency service fallback, or transmitting a response to a network paging request.

[0307] (1) Step 1: The UE can transmit a service request message to the (R)AN.

[0308] (2) Step 2: The (R)AN can transmit an N2 message to the AMF.

[0309] The N2 message can include a service request.

[0310] (3) Step 3: A security authentication procedure can be performed.

[0311] (4) Step 4: The AMF can send the Nsmf_PDUSession_UpdateSMContext request to the SMF.

[0312] (5a) Step 5a: The SMF can initiate SM Policy Association Modification.

[0313] (5b) Step 5b: The SMF can select a UPF.

[0314] (6a) Step 6a: The SMF can send an N4 Session Modification Request message to the UPF (PSA).

[0315] (6b) Step 6b: The UPF (PSA) can send an N4 Session Modification Response message to the SMF.

[0316] (6c) Step 6c: The SMF can send an N4 Session Establishment Request message to the UPF (intermediate).

[0317] (6d) Step 6d: The UPF (intermediate) can send an N4 Session Establishment Response message to the SMF.

[0318] (7a) Step 7a: The SMF can send an N4 Session Modification Request message to the UPF (PSA).

[0319] (7b) Step 7b: The UPF (PSA) can send an N4 Session Modification Response message to the SMF.

[0320] (8a) Step 8a: The SMF can send an N4 Session Modification Request message to the UPF (intermediate).

[0321] (8b) Step 8b: The UPF (intermediate) can send an N4 Session Modification Response message to the SMF.

[0322] (9) Step 9: The old UPF (intermediate) can send the buffered downlink data forwarding to the new UPF (intermediate).

[0323] (10) Step 10: The old UPF (intermediate) can send the buffered downlink data forwarding to the UPF (PSA).

[0324] (11) Step 11: The SMF can send the Nsmf_PDUSession_UpdateSMContext Response to the AMF.

[0325] The Nsmf_PDUSession_UpdateSMContext Response can include N2 SM information, N1 SM container, and cause. The N2 SM information can include PDU Session pair ID (identifier).

[0326] RSN and PDU Session pair ID can be included if determined applicable by the SMF during PDU Session establishment.

[0327] (12) Step 12: The AMF can send the N2 Request to the (R)AN.

[0328] (13) Step 13: The NG-RAN can perform RRC Connection Reconfiguration with the UE according to the QoS information.

[0329] If the NG-RAN is not able to establish redundancy user plane for the PDU Session as indicated by the RSN and PDU Session pair ID, the NG-RAN can decide how to continue the PDU Session.

[0330] (14) Step 14: The (R)AN can send the N2 Request Ack to the AMF.

[0331] (15) Step 15: The AMF can send the Nsmf_PDUSession_UpdateSMContext Request to the SMF.

[0332] (16) Step 16: If dynamic PCC is deployed, the SMF can initiate the notification of the new location information about the PCF (if subscribed) by performing the SMF- initiated SM Policy modification procedure. The PCF can provide the updated policy.

[0333] (17a) Step 17a: The SMF can send the N4 Session Modification Request to the new intermediate UPF.

[0334] (17b) Step 17b: The UPF can send the N4 Session Modification Response to the SMF.

[0335] (18a) Step 18a: The SMF can send the N4 Session Modification Request to the UPF (PSA).

[0336] (18b) Step 18b: The UPF can send the N4 Session Modification Response to the SMF.

[0337] (19) Step 19: The SMF can send the Nsmf_PDUSession_UpdateSMContext Response to the AMF.

[0338] (20a) Step 20a: The SMF can send the N4 Session Modification Request to the new UPF (intermediate).

[0339] (20b) Step 20b: The new UPF (intermediate) can send the N4 Session Modification Response to the SMF.

[0340] (21a) Step 21a: The SMF can send the N4 Session Modification Request to the UPF (PSA).

[0341] (21b) Step 21b: The UPF (PSA) can send an N4 Session Modification Response to the SMF.

[0342] (22a) Step 22a: The SMF can send an N4 Session Modification Request or an N4 Session Release Request to the old UPF.

[0343] (22b) Step 22b: The old intermediate UPF can send an N4 Session Modification Response or an N4 Session Release Response to the SMF.

[0344] 4. Fourth implementation

[0345] Figure 13 and Figure 14 An example of the fourth implementation of the present specification is shown.

[0346] The PDU Session Establishment can correspond to:

[0347] - UE initiated PDU Session Establishment procedure

[0348] - UE initiated PDU Session handover between 3GPP and non-3GPP

[0349] - UE initiated PDU Session handover from EPS to 5GS.

[0350] - Network triggered PDU Session Establishment procedure

[0351] A PDU Session can be (a) associated with a single connection type (i.e. 3GPP connection or non-3GPP connection) at any given time, or (b) simultaneously associated with multiple connection types (i.e. one 3GPP connection and one non-3GPP connection). A PDU Session associated with multiple access types is referred to as a Multiple Access (MA) PDU Session and can be requested by a UE that supports ATSSS (Access Traffic Steering, Switching, Splitting).

[0352] Figure 13 and Figure 14 Procedures for establishing a PDU Session associated with a single connection type at a given time are specified.

[0353] In the procedures shown in Figure 13 and Figure 14 Since the UE has registered with the AMF, it is assumed that the AMF has retrieved the user subscription data from the UDM, unless the UE is registered urgently.

[0354] First, the procedure of Figure 13 will be described.

[0355] (1) Step 1: The UE generates a new PDU Session ID in order to establish a new PDU Session.

[0356] The UE initiates the UE-requested PDU session establishment procedure by transmitting a NAS message containing a PDU session establishment request within an N1 SM container. The PDU session establishment request can include a PDU session ID, a requested PDU session type, a requested SSC mode, a 5GSM capability, a PCO, an SM PDU DN request container, a [number of packet filters], a [header compression configuration], a UE integrity protection maximum data rate, a [requested always-on PDU session], and a PDU session pair identifier.

[0357] If the PDU session establishment is a request to establish a new PDU session, the request type indicates "initial request", if the request is a handover of an existing PDU session between 3GPP access and non-3GPP access or a PDU session handover from an existing PDN connection in EPC, it indicates "existing PDU session". If the PDU session establishment is a request to establish a PDU session for emergency services, the request type indicates "emergency request". If the request is a handover of an existing PDU session for emergency services between 3GPP connection and non-3GPP connection or a PDU session handover from an existing PDN connection for emergency services in EPC, the request type indicates "existing emergency PDU session".

[0358] The UE includes S-NSSAIs from the allowed NSSAI of the current connection type. If an allowed NSSAI mapping is provided to the UE, the UE provides both the S-NSSAIs from the allowed NSSAI that are access VPLMN (VPLMN) and the corresponding S-NSSAIs from the HPLMN of the allowed NSSAI mapping.

[0359] When the UE establishes a PDU session for redundant transmission and the UE is configured by the PCF to include a PDU session pair ID, the UE can include the PDU session pair ID in the PDU session establishment request message.

[0360] (2) Step 2: The AMF selects an SMF. If the request type indicates "initial request", or if the request is due to a handover from EPS or a non-3GPP connection provided by another AMF, the AMF stores not only the connection type of the PDU session, but also the association of S-NSSAI, DNN (Data Network Name), PDU session ID, and SMF ID.

[0361] If the request type is "initial request" and if the old PDU session ID indicating an existing PDU session is also included in the message, the AMF selects an SMF and stores the association of the new PDU session ID, S-NSSAI, selected SMF ID, and the access type of the PDU session.

[0362] If the request type indicates "existing PDU Session", the AMF selects the SMF based on the SMF-ID received from the UDM. The AMF updates the access type stored for the PDU Session.

[0363] If the request type indicates "existing PDU Session" (referring to an existing PDU Session moving between 3GPP access and non-3GPP access), the PDU Session establishment procedure can be executed if the service PLMN S-NSSAI of the PDU Session exists in the allowed NSSAI of the target access type in the following cases:

[0364] - the SMF ID and the AMF corresponding to the PDU Session ID belong to the same PLMN;

[0365] - the SMF ID corresponding to the PDU Session ID belongs to the HPLMN;

[0366] Otherwise, the AMF shall reject the PDU Session establishment request with an appropriate rejection cause.

[0367] The AMF shall reject the request from an emergency registered UE and the request type does not indicate "emergency request" nor "existing emergency PDU Session".

[0368] (3) Step 3: If the AMF is not associated with the SMF of the PDU Session ID provided by the UE (e.g., when the request type indicates "initial request"), the AMF invokes the Create SM Context Request procedure (e.g., Nsmf_PDUSession_CreateSMContext request). If the AMF is already associated with the SMF of the PDU Session ID provided by the UE (e.g., when the request type indicates "existing PDU Session"), the AMF invokes the Update SM Context Request procedure (e.g., Nsmf_PDUSession_UpdateSMContext request).

[0369] The AMF sends to the SMF the S-NSSAI from the service PLMN of the allowed NSSAI. For roaming scenarios in Local Breakout (LBO), the AMF also sends to the SMF the corresponding S-NSSAI from the HPLMN of the allowed NSSAI mapping.

[0370] The AMF ID is the GUAMI of the UE, which uniquely identifies the AMF serving the UE. The AMF forwards the PDU Session ID together with the N1 SM container containing the PDU Session establishment request received from the UE. The GPSI shall be included if available at the AMF.

[0371] When a UE in a restricted service state has registered for emergency services (i.e., emergency registration) without providing a SUPI, the AMF provides a PEI instead of a SUPI. If a UE in a restricted service state has registered for emergency services (i.e., emergency registration) to a SUPI but has not been authenticated yet, the AMF indicates that the SUPI has not been authenticated. When no SUPI of the UE is received or when the AMF indicates that the SUPI has not been authenticated, the SMF determines that the UE has not been authenticated.

[0372] The AMF can include the PCF ID in the Nsmf_PDUSession_CreateSMContext. This PCF ID identifies the H-PCF (Home PCF) in the non-roaming case and the V-PCF (Visited PCF) in the LBO roaming case.

[0373] (4) Step 4: If session management subscription data for the corresponding SUPI, DNN and S-NSSAI of the HPLMN is not available, the SMF can retrieve the session management subscription data from the UDM and can be notified when the session management subscription data is modified.

[0374] (5) Step 5: The SMF sends a Create SM Context Response message (e.g., Nsmf_PDUSession_CreateSMContext Response) or an Update SM Context Response message (e.g., Nsmf_PDUSession_UpdateSMContext Response) to the AMF according to the request received in Step 3.

[0375] If the SMF receives the Nsmf_PDUSession_CreateSMContext request in Step 3 and is able to process the PDU session establishment request, the SMF creates the SM context and responds to the AMF by providing the SM context ID.

[0376] When the SMF decides not to accept the establishment of the PDU session, the SMF rejects the UE request via including the relevant SM rejection cause in the NAS SM signaling by responding to the AMF with the Nsmf_PDUSession_CreateSMContext Response. The SMF also indicates to the AMF that the PDU session ID is to be considered as released, the SMF proceeds to Step 20, and the PDU session establishment procedure stops.

[0377] (6) Step 6: Optional secondary authentication / authorization can be performed.

[0378] (7a) Step 7a: If dynamic PCC (Policy and Charging Control) is to be used for the PDU session, the SMF performs PCF selection.

[0379] (7b) Step 7b: The SMF can perform the SM Policy Association establishment procedure to establish SM Policy Association with the PCF and get the default PCC rules for the PDU Session.

[0380] (8) Step 8: The SMF selects one or more UPFs.

[0381] (9) Step 9: The SMF can provide information about the policy control request trigger conditions that are fulfilled by performing the SMF initiated SM Policy Association modification procedure.

[0382] (10) Step 10: If the request type indicates "initial request", the SMF can initiate the N4 Session Establishment procedure with the selected UPF. Otherwise, the SMF can initiate the N4 Session Modification procedure with the selected UPF.

[0383] In step 10a, the SMF can send the N4 Session Establishment / Modification request to the UPF and provide packet detection, enforcement and reporting rules to be installed in the UPF for the PDU Session. In step 10b, the UPF can confirm by sending the N4 Session Establishment / Modification response.

[0384] (11) Step 11: The SMF sends the N1N2MessageTransfer message (e.g., Namf_Communication_N1N2MessageTransfer) to the AMF.

[0385] The N1N2MessageTransfer message can include the PDU Session ID.

[0386] The N1N2MessageTransfer message can include the N2 SM information. The N2 SM information carries information that the AMF should forward to the (R)AN, including:

[0387] - CN Tunnel Info corresponding to the core network address of the N3 tunnel corresponding to the PDU Session;

[0388] - one or more QoS profiles and corresponding QFIs;

[0389] - PDU Session ID indicating the association between the (R)AN resources and the PDU Session of the UE to the UE;

[0390] - S-NSSAI with the value of the serving PLMN (i.e., HPLMN S-NSSAI, or VPLMN S-NSSAI in case of LBO roaming);

[0391] - User Plane Security Enforcement information determined by the SMF;

[0392] - If the user plane security enforcement information indicates integrity protection is "preferred" or "required", the SMF also includes the UE integrity protection maximum data rate.

[0393] - RSN (redundancy sequence number) parameter and PDU session pair ID

[0394] The N1 N2 Message Transfer message can contain an N1 SM container. The N1 SM container includes the PDU session establishment accept message that the AMF will provide to the UE. The PDU session establishment accept message contains the S-NSSAIs from the allowed NSSAI. For LBO roaming scenarios, the PDU session establishment accept message contains the S-NSSAIs from the allowed NSSAI of the VPLMN and the corresponding S-NSSAIs from the HPLMN of the allowed NSSAI mapping received by the SMF in step 3.

[0395] The multiple QoS rules, the QoS flow level QoS parameters of the QoS flows associated with these QoS rules (if needed) and the QoS profile can be included in the PDU session establishment accept within the N1 SM and in the N2 SM information.

[0396] If the PDU session establishment fails anywhere between step 5 and step 11, the N1 N2 Message Transfer message shall include the N1 SM container with the PDU session establishment reject message and shall not include any N2 SM container. The (R)AN sends the NAS message containing the PDU session establishment reject to the UE. In this case, steps 12-17 are skipped.

[0397] (12) Step 12: The AMF sends to the (R)AN the N2 PDU session request message (including the NAS message to the UE with the PDU session ID and the PDU session establishment accept message and the N2 SM information received from the SMF).

[0398] (13) Step 13: The (R)AN can perform with the UE an AN specific signalling exchange related to the information received from the SMF. For example, in the case of NG-RAN, an RRC connection reconfiguration can be performed by the UE in case it establishes the necessary NG-RAN resources related to the QoS rules in the PDU session request received in step 12.

[0399] The (R)AN forwards the NAS message provided in step 12 (PDU session ID, N1 SM container (PDU session establishment accept)) to the UE. If the AN specific signalling exchange with the UE includes (R)AN resource addition associated with the received N2 command, the (R)AN shall only provide the NAS message to the UE.

[0400] If N2 SM information is not included in step 11, the following steps 14 to 16b and step 17 are omitted.

[0401] Now, the procedure after the procedure of Figure 13 is described. Figure 14

[0402] (14) Step 14: (R)AN sends N2 PDU Session Response message to AMF. The N2 PDU Session Response message can include PDU Session ID, Cause, N2 SM information (PDU Session ID, AN Tunnel Info, Accepted / Rejected QFI List, User Plane Enforcement Policy Notification), etc.

[0403] If NG-RAN is unable to establish redundant user plane for the PDU Session as indicated by RSN and PDU Session ID, NG-RAN decides based on local policy whether to reject the establishment of RAN resources for the PDU Session.

[0404] (15) Step 15: AMF sends Update SM Context Request message (e.g., Nsmf_PDUSession_UpdateSMContext Request) to SMF. The AMF forwards the N2 SM information received from (R)AN to SMF.

[0405] (16a) Step 16a: SMF initiates N4 Session Modification procedure with UPF. The SMF provides AN Tunnel Info and corresponding forwarding rules to UPF.

[0406] (16b) Step 16b: UPF provides N4 Session Modification Response to SMF.

[0407] After this step, UPF delivers to the UE any downlink packets that can have been buffered for this PDU Session.

[0408] (16c) Step 16c: If the SMF has not registered the PDU Session, the SMF can register the given PDU Session with UDM.

[0409] (17) Step 17: SMF sends Update SM Context Response message (e.g., Nsmf_PDUSession_UpdateSMContext Response) to AMF.

[0410] After this step, the AMF forwards relevant events that the SMF is subscribed to.

[0411] ​(18) Step 18: If during this procedure, at any time after step 5, the PDU session establishment is not successful, the SMF can inform the AMF by invoking Nsmf_PDUSession_SMContextStatusNotify (release). The SMF can also release any N4 session created, any PDU session address (if allocated) (e.g. IP address), and can release the association with the PCF (if any). In this case, step 19 can be skipped.

[0412] (19) Step 19: In case of PDU session type IPv6 or IPv4v6, the SMF can generate an IPv6 Router Advertisement and can send it to the UE.

[0413] (20) Step 20: The SMF can perform SMF-initiated SM policy association modification.

[0414] (21) Step 21: If the PDU session establishment fails after step 4, the SMF can unsubscribe from the modification of the session management subscription data if the SMF is not handling the PDU session of the UE anymore as a result.

[0415] 5. Fifth embodiment

[0416] Figure 15 An example of the fifth embodiment of the present specification is shown.

[0417] The fifth embodiment can relate to a case where the UE initially registers with the network. The fifth embodiment can relate to a case where the AMF is relocated due to a PCF change in a handover procedure or a registration procedure. The fifth embodiment can relate to a case where the UE registers with the 5GS when moving from the EPS to the 5GS. The fifth embodiment can relate to a case where there is no UE policy association between the AMF and the PCF.

[0418] (1) Step 1: When receiving the UE policy container from the UE, the AMF can establish a UE policy association with the (V-)PCF. If no UE policy container is received from the UE, the AMF can establish a UE policy association with the (V-)PCF based on the AMF local configuration.

[0419] (2) Step 2: The AMF can send the Npcf_UEPolicyControl create request to the V-PCF.

[0420] The Npcf_UEPolicyControl create request includes the SUPI, the access type and RAT, the PEI, the ULI, the UE time zone, the serving network (PLMN ID or PLMN ID and NID), the list of internal group IDs, and the UE policy container (storing the list of PSI, the operating system identifier, the UE support indication of ANDSP).

[0421] The Npcf_UEPolicyControl creation request can include an indication of whether the UE supports PDU session to ID.

[0422] (3) Step 3: The V-PCF can forward the information received from the AMF in step 2 to the H-PCF.

[0423] (4) Step 4: The H-PCF can send the Npcf_UEPolicyControl creation response to the V-PCF.

[0424] (5) Step 5: The (V-)PCF can send the Npcf_UEPolicyControl creation response to the AMF.

[0425] (6) Step 6: The H-PCF can send the Npcf_UEPolicyControlUpdateNotify request to the V-PCF.

[0426] (7) Step 7: The V-PCF can send the Npcf_UEPolicyControlUpdateNotify response to the H-PCF.

[0427] (8) Step 8: The (V-)PCF triggers the UE configuration update procedure to send the UE policy container including the UE policy information to the UE. The (V-)PCF checks the size limit.

[0428] (9) Step 9: The V-PCF can send the Npcf_UEPolicyControl_Update request to the H-PCF.

[0429] (10) Step 10: The H-PCF can respond to the Npcf_UEPolicyControl_Update response to the V-PCF.

[0430] <ursp>

[0431] A UE Route Selection Policy (URSP) comprises a prioritized list of URSP rules.

[0432] Table 5 shows URSP.

[0433] [Table 5]

[0434]

[0435] The structure of URSP is shown in Table 6 and Table 7. Table 6 shows URSP rule.

[0436] [Table 6]

[0437]

[0438] Table 7 shows RSD (Route Selection Descriptor).

[0439] [Table 7]

[0440]

[0441]

[0442] Each URSP rule contains a traffic descriptor (containing one or more components described in Table 4) that determines when the rule is applicable. A URSP rule is determined to be applicable when each component in the traffic descriptor matches the corresponding information from the application.

[0443] - If no corresponding information from the application is available or the corresponding information from the application does not match any value in the traffic descriptor components, the URSP rule is determined to be not applicable for any given component in the traffic descriptor.

[0444] It is recommended to avoid listing more than two components in the traffic descriptor of a URSP rule.

[0445] If a URSP rule is provided that contains a traffic descriptor with two or more components, it is recommended to also provide a lower-priority URSP rule and a traffic descriptor with fewer components in order to increase the likelihood of the URSP rule matching for a particular application.

[0446] Each URSP rule contains a list of route selection descriptors that contains one or more route selection descriptors, each with a different route selection descriptor priority value. A route selection descriptor contains one or more of the following components:

[0447] - Session and Service Continuity (SSC) mode: indicates that traffic for the matching application should be routed via a PDU session that supports the included SSC mode.

[0448] - Network Slice Selection: indicates that traffic matching the application shall be routed via PDU Sessions that support any of the included S-NSSAIs. It includes one or more S-NSSAI.

[0449] - DNN Selection: indicates that traffic matching the application shall be routed via PDU Sessions that support any of the included DNNs. It includes one or more DNNs. When a DNN is used in a traffic descriptor, the corresponding routing selection descriptor of the rule shall not include a DNN selection component.

[0450] - PDU Session Type Selection: indicates that traffic matching the application shall be routed via PDU Sessions that support the included PDU Session Type.

[0451] - Non-seamless offload indication: indicates that when the rule is applied, traffic matching the application is to be offloaded to non-3GPP access outside of a PDU Session. If this component is present in a routing selection descriptor, no other component shall be included in the routing selection descriptor.

[0452] - Access Type Preference: if the UE needs to establish a PDU Session when the rule is applied, this indicates the access type (3GPP or non-3GPP or multi-access) that the PDU Session should be established. Type "multi-access" indicates that the PDU Session should be established using both 3GPP access and non-3GPP access as a MA PDU Session.

[0453] - PDU Session Pair Identifier: indicates which PDU Sessions are paired for redundant transmission when the UE establishes redundant PDU Sessions.

[0454] - Time Window: the routing selection descriptor is not considered valid unless the UE is in that time window.

[0455] - Location Criteria: the routing selection descriptor is not considered valid unless the UE's location matches the location criteria.

[0456] The structure of URSP does not define how the PCF splits the URSP when it cannot be transported to the UE in a single NAS message.

[0457] It is expected that the UE application will not be able to change or override PDU Session parameters in the URSP rules. The UE application can express preferences when requesting network connectivity (e.g., certain connection capabilities) which can be mapped to specific PDU Session parameters by the URSP rules.

[0458] When one routing selection descriptor in a URSP rule contains a time window or location criteria, all routing selection descriptors in the URSP rule must contain a time window or location criteria.

[0459] In case the network rejects the PDU session establishment request, the UE can trigger a new PDU session establishment based on the rejection cause and URSP policy.

[0460] When the PCF provides URSP rules to the UE, one URSP rule with the "match-all" traffic descriptor can be included.

[0461] When URSP rules containing NSSP are available to the UE and the URSP rules with the "match-all" traffic descriptor are not part of them, no URSP rule is matched and the UE application without UE locally configured cannot request a network connection.

[0462] The URSP rule with the "match-all" traffic descriptor is used to route traffic for applications that do not match any other URSP rule and should therefore be evaluated as the last URSP rule (i.e. with the lowest priority). There should only be one routing descriptor in this URSP rule. For each routing component, the routing descriptor in this URSP rule includes at most one value.

[0463] 6. Sixth embodiment

[0464] The sixth embodiment provides a method of configuring PDU session pair ID information and RSN information in a UE.

[0465] Redundant PDU session (RPS) related information (RPS policy / parameters) can be configured in the UE. The information related to redundant PDU session can be one or more of PDU session pair ID information and RSN information. These configurations can be configured in the UICC and / or ME of the UE. Alternatively, it can be configured or updated from the network (e.g. PCF, AMF, etc.). The configuration can be in one or more of the following forms:

[0466] i) Mapping of traffic descriptors of PDU sessions requiring redundant transmission to PDU session pair ID information and / or RSN information.

[0467] ii) Mapping of DNNs and / or S-NSSAIs of PDU sessions requiring redundant transmission to PDU session pair ID information and / or RSN information.

[0468] iii) Mapping of routing descriptors of PDU sessions requiring redundant transmission to PDU session pair ID information and / or RSN information.

[0469] PDU sessions requiring redundant transmission can mean PDU sessions for URLLC service or PDU sessions supporting URLLC QoS flows.

[0470] Two or more mapping information with the same PDU session pair ID are configured in the UE. In other words, two or more PDU sessions corresponding to the same PDU session pair ID are PDU sessions for redundant transmission.

[0471] When the UE creates a PDU session for redundant transmission based on the configuration, the UE provides PDU session pair ID information and / or RSN information to the network (i.e., SMF). After receiving the information, the SMF can provide the information to the RAN.

[0472] For example, if the following configuration is performed on the UE, a PDU session generated corresponding to Traffic_Descriptor#A and a PDU session generated corresponding to Traffic_Descriptor#B are PDU sessions for redundant transmission (i.e., paired PDU sessions). The UE provides PDU session pair ID#1 and / or RSN#x information when requesting the generation of a PDU session generated corresponding to Traffic_Descriptor#A through the SMF. In addition, the UE provides PDU session pair ID#1 and / or RSN#y information when requesting the generation of a PDU session generated corresponding to Traffic_Descriptor#B through the SMF.

[0473] - Mapping of Traffic_Descriptor#A of a PDU session requiring redundant transmission to PDU session pair ID#1 and / or RSN#x

[0474] - Mapping of Traffic_Descriptor#B of a PDU session requiring redundant transmission to PDU session pair ID#1 and / or RSN#y

[0475] For example, if the following configuration is performed in the UE, a PDU session generated corresponding to DNN#a and / or S-NSSAI#a and a PDU session generated corresponding to DNN#b and / or S-NSSAI#b are PDU sessions for redundant transmission (i.e., paired PDU sessions). When requesting the generation of a PDU session generated corresponding to DNN#a and / or S-NSSAI#a through the SMF, the UE provides PDU session pair ID#2 and / or RSN#X information. In addition, when requesting the generation of a PDU session generated corresponding to DNN#b and / or S-NSSAI#b through the SMF, the UE provides PDU session pair ID#2 and / or RSN#Y information.

[0476] - Mapping of DNN#a and / or S-NSSAI#a of a PDU session requiring redundant transmission to PDU session pair ID#2 and / or RSN#X

[0477] - Mapping of DNN#b and / or S-NSSAI#b of PDU session requiring redundant transmission to PDU session pair ID#2 and / or RSN#Y

[0478] In the above, the UE can check the RPS policy / parameter for the creation of all PDU sessions and apply the corresponding information if there is information. However, the information that the UE has to check the presence of the RPS policy / parameter can be included in the URSP.

[0479] For example, if the UE has the configuration of the above i), the information that the UE has to check the presence of the RPS policy / parameter in the RSD information matching / corresponding to the traffic descriptor in the URSP or newly defined information can be included.

[0480] For example, if the UE has the configuration of the above ii), the information that the UE has to check the presence of the RPS policy / parameter in the RSD along with the corresponding DNN and / or S-NSSAI of the URSP or other newly defined information in the URSP can be included.

[0481] Figure 16 A procedure of a PCF for the disclosure of the present specification is shown.

[0482] (1) Step 1: The PCF can receive a UE (User Equipment) policy association establishment message from an AMF (Access and Mobility Management Function).

[0483] (2) Step 2: The PCF can transmit a URSP (UE Route Selection Policy) rule to the UE.

[0484] The URSP rule can include a first RSD (Route Selection Descriptor) and a second RSD.

[0485] The first RSD can include a PDU (Protocol Data Unit) session pair ID (Identifier).

[0486] The PDU session pair ID can be used to establish two redundant PDU sessions.

[0487] The second RSD can not include the PDU session pair ID.

[0488] The first RSD can have a higher priority value than the second RSD.

[0489] The PDU session pair ID can indicate two redundant PDU sessions.

[0490] The two redundant PDU sessions can be paired for redundant transmission.

[0491] Figure 17 A procedure of a UE for the disclosure of the present specification is shown.

[0492] (1) Step 1: The UE can transmit a registration request message to the network.

[0493] The network can be an NG-RAN. The network can be an AMF.

[0494] (2) Step 2: The UE can receive a URSP (UE Route Selection Policy) rule from a PCF (Policy Control Function).

[0495] The URSP rule can include a first RSD (Route Selection Descriptor) and a second RSD.

[0496] The first RSD can include a PDU (Protocol Data Unit) session pair ID (identifier).

[0497] The PDU session pair ID can be used to establish two redundant PDU sessions.

[0498] The second RSD can not include the PDU session pair ID.

[0499] The first RSD can have a higher priority value than the second RSD.

[0500] The PDU session pair ID can indicate the two redundant PDU sessions.

[0501] The two redundant PDU sessions can be paired for redundant transmission.

[0502] The UE can check the first RSD. Based on the UE identifying the PDU session pair ID in the first RSD, the UE can skip checking the second RSD. Based on the UE identifying the PDU session pair ID in the first RSD, the UE can perform a procedure for establishing the two redundant PDU sessions based on the first RSD.

[0503] The UE can check the first RSD. Based on the UE not identifying the PDU session pair ID in the first RSD, the UE can check the second RSD. Based on the UE not identifying the PDU session pair ID in the first RSD, the UE can perform a procedure for establishing the two redundant PDU sessions based on the second RSD.

[0504] Hereinafter, a processor for providing communication in a wireless communication system according to some embodiments of the present specification will be described.

[0505] For example, the PCF can include a processor, a transceiver, and a memory.

[0506] For example, the processor can be configured to be operatively coupled with the memory and the processor.

[0507] The processor can perform operations including receiving a UE (User Equipment) policy association establishment message from an AMF (Access and Mobility Management Function).

[0508] The processor can perform operations including transmitting, to the UE, a URSP (UE route selection policy) rule, wherein the URSP rule includes a first RSD (route selection descriptor) and a second RSD, wherein the first RSD includes a PDU (protocol data unit) session pair ID (identifier), wherein the PDU session pair ID is used to establish two redundant PDU sessions, wherein the second RSD does not include the PDU session pair ID.

[0509] Hereinafter, a non-transitory computer-readable medium storing one or more instructions for providing communication according to some embodiments of the present specification will be described.

[0510] According to some embodiments of the present disclosure, the technical features of the present disclosure can be directly embodied as hardware, software executed by a processor, or a combination of the two. For example, in wireless communication, a method performed by a wireless device can be implemented in hardware, software, firmware, or any combination thereof. For example, the software can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or other storage medium.

[0511] Some examples of the storage medium are coupled to the processor such that the processor can read information from, and write information to, the storage medium. In other examples, the storage medium is integral to the processor. The processor and the storage medium can reside in an ASIC. In some examples, the processor and the storage medium can be separate components, e.g., a separate component.

[0512] The computer-readable medium can include tangible and non-transitory computer-readable storage media.

[0513] For example, the non-transitory computer-readable medium can include random access memory (RAM), such as synchronous dynamic random access memory (SDRAM), read-only memory (ROM), or non-volatile random access memory (NVRAM). The computer-readable medium can also include other types of storage media, including a hard disk drive, a solid state drive, a flash drive, a magnetic or optical data storage medium, or other storage media, or a combination of the above.

[0514] In addition, the methods described herein can be implemented at least in part by a computer-readable communication medium that carries or communicates code or data structures in the form of instructions or data structures and that can be accessed, read, and / or executed by a computer.

[0515] According to some embodiments of the present disclosure, a non-transitory computer-readable medium stores one or more instructions. The stored one or more instructions can be executed by a processor of a UE.

[0516] The stored one or more instructions cause the processor to: receive, from an AMF (access and mobility management function), a UE (user equipment) policy association establishment message; transmit, to the UE, a URSP (UE route selection policy) rule, wherein the URSP rule includes a first RSD (route selection descriptor) and a second RSD, wherein the first RSD includes a PDU (protocol data unit) session pair ID (identifier), wherein the PDU session pair ID is used to establish two redundant PDU sessions, wherein the second RSD does not include the PDU session pair ID.

[0517] The present specification can have various effects.

[0518] For example, by the procedures disclosed in the present specification, a network can establish redundant PDU sessions by managing terminals that support a PDU session pair ID and terminals that do not support a PDU session pair ID as a whole.

[0519] Effects obtainable by specific examples of the present specification are not limited to the above-mentioned effects. For example, various technical effects that can be understood or inferred from the present specification by those of ordinary skill in the related art can be present. Therefore, specific effects of the present specification are not limited to those explicitly described herein, and can include various effects that can be understood or inferred from technical features of the present specification.

[0520] The claims described herein can be combined in various ways. For example, technical features of method claims of the present specification can be combined and implemented as an apparatus, technical features of apparatus claims of the present specification can be combined and implemented as a method. In addition, technical features of method claims and technical features of apparatus claims of the present specification can be combined to be implemented as an apparatus, and technical features of method claims and technical features of apparatus claims of the present specification can be combined and implemented as a method. Other implementations are within the scope of the following claims.< / ursp>

Claims

1. A method performed by a policy control function, PCF, for performing communication, the method comprising the steps of: receiving, from an access and mobility management function, AMF, a user equipment, UE, policy container; sending, to the UE, a UE route selection policy, URSP, rule, wherein the URSP rule comprises a first route selection descriptor, RSD, and a second RSD, wherein the first RSD comprises a protocol data unit, PDU, session pair identifier, ID, wherein the PDU session pair ID is used to establish two redundant PDU sessions, wherein the second RSD does not comprise the PDU session pair ID.

2. The method of claim 1, wherein the first RSD has a higher priority value than the second RSD.

3. The method of claim 1 or claim 2, wherein the PDU session pair ID indicates the two redundant PDU sessions.

4. The method of any of claims 1 to 3, wherein, the two redundant PDU sessions are paired for redundant transmission.

5. The method of any of claims 1 to 4, wherein the UE policy container comprises information about whether the UE supports PDU session pair ID.

6. A method performed by a user equipment, UE, for performing communication, the method comprising the steps of: sending, to a base station, a registration request message; receiving, from a policy control function, PCF, a UE route selection policy, URSP, rule, wherein the URSP rule comprises a first route selection descriptor, RSD, and a second RSD, wherein the first RSD comprises a protocol data unit, PDU, session pair identifier, ID, wherein the PDU session pair ID is used to establish two redundant PDU sessions, wherein the second RSD does not comprise the PDU session pair ID.

7. The method of claim 6, wherein the first RSD has a higher priority value than the second RSD.

8. The method of claim 6 or claim 7, wherein the PDU session pair ID indicates the two redundant PDU sessions.

9. The method of any of claims 6 to 8, wherein, the two redundant PDU sessions are paired for redundant transmission.

10. The method of any of claims 6 to 9, further comprising the steps of: checking the first RSD; based on the UE identifying the PDU session pair ID in the first RSD, skipping checking the second RSD; based on the UE identifying the PDU session pair ID in the first RSD, performing a procedure for establishing the two redundant PDU sessions based on the first RSD.

11. The method of any of claims 6 to 9, further comprising the steps of: checking the first RSD; based on the UE not identifying the PDU session pair ID in the first RSD, checking the second RSD; based on the UE not identifying the PDU session pair ID in the first RSD, performing a procedure for establishing the two redundant PDU sessions based on the second RSD.

12. The method of any of claims 6 to 11, wherein, the registration request message comprises information about whether the UE supports PDU session pair ID.

13. A policy control function (PCF), the PCF comprising: a transceiver that transmits signals and receives signals; and a processor that controls the transceiver, wherein the processor performs operations, wherein the operations are the method according to any one of claims 1 to 5.

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