WO2024210592A1

WO2024210592A1 - Communication based on network slice

Info

Publication number: WO2024210592A1
Application number: PCT/KR2024/004476
Authority: WO
Inventors: Hyunjung CHOE; Hyunsook Kim
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2023-04-07
Filing date: 2024-04-05
Publication date: 2024-10-10
Anticipated expiration: 2025-10-07

Abstract

The present disclosure provides a method performed by a UE. The method may include: transmitting registration request message including capability information to a first network entity related to mobility management; receiving registration accept message from the first network entity; transmitting information related to unavailability of a network slice to the first network entitity; and receiving updated URSP rule or UE configuration for the network slice from the first network entity or a second network entity related to session management.

Description

COMMUNICATION BASED ON NETWORK SLICE

The present specification relates to a radio communication.

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 and system capacity. The 3GPP LTE requires reduced cost per bit, increased service availability, flexible use of a frequency band, a simple structure, an open interface, and adequate power consumption of a terminal as an upper-level requirement.

Work has started in International Telecommunication Union (ITU) and 3GPP to develop requirements and specifications for New Radio (NR) systems. 3GPP has to identify and develop the technology components needed for successfully standardizing the new RAT timely satisfying both the urgent market needs, and the more long-term requirements set forth by the ITU Radio communication sector (ITU-R) International Mobile Telecommunications (IMT)-2020 process. Further, the NR should be able to use any spectrum band ranging at least up to 100 GHz that may be made available for wireless communications even in a more distant future.

The NR targets a single technical framework addressing all usage scenarios, requirements and deployment scenarios including enhanced Mobile BroadBand (eMBB), massive Machine Type Communications (mMTC), Ultra-Reliable and Low Latency Communications (URLLC), etc. The NR shall be inherently forward compatible.

On-demand S-NSSAI is intorduced for registering a network slice when a Protocla Data Unit (PDU) session for actual transmission of user data is established. However, UE policy management for the on-demand S-NSSAI cannot be performed efficiently and/or precisely in the prior arts.

In one aspect, a method performed by a UE is provided. The method may comprise transmitting registration request message including capability information to a first network entity related to mobility management; receiving registration accept message from the first network entity; transmitting information related to unavailability of a network slice to the first network entitity; and receiving updated URSP rule or UE configuration for the network slice from the first network entity or a second network entity related to session management.

In another aspect, an appartus performing the above method is provided.

In one aspect, a method performed by a first network entity related to mobility management is provided. The method may comprise receiving registration request message including capability information to from a UE; transmitting registration accept message to the UE; receiving information related to unavailability of a network slice from the UE; and transmitting updated URSP rule or UE configuration for the network slice to the UE

In another aspect, an appartus performing the above method is provided.

FIG. 1 shows an example of a communication system to which implementations of the present disclosure is applied.

FIG. 2 shows an example of wireless devices to which implementations of the present disclosure is applied.

FIG. 3 shows an example of UE to which implementations of the present disclosure is applied.

FIG. 4 shows an example of 5G system architecture to which implementations of the present disclosure is applied.

FIGS. 5 and 6 show an example of a registration procedure to which implementations of the present disclosure is applied.

FIG. 7 is an exemplary diagram illustrating an example of an architecture for implementing the concept of network slicing.

FIG. 8 is an exemplary diagram illustrating another example of an architecture for implementing the concept of network slicing.

FIGS. 9 and 10 show an example of a PDU session establishment procedure to which implementations of the present disclosure is applied.

FIG. 11 illustrates an example of operations according to an embodiment of the present disclosure.

FIG. 12 illustrates an example of an operation according to an embodiment of the present disclosure.

The following techniques, apparatuses, and systems may be applied to a variety of 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 Multi Carrier Frequency Division Multiple Access (MC-FDMA) system. CDMA may be embodied through radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000. TDMA may 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). OFDMA may 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). UTRA is a part of a Universal Mobile Telecommunications System (UMTS). 3rd Generation Partnership Project (3GPP) Long-Term Evolution (LTE) is a part of Evolved UMTS (E-UMTS) using E-UTRA. 3GPP LTE employs OFDMA in downlink (DL) and SC-FDMA in uplink (UL). Evolution of 3GPP LTE includes LTE-Advanced (LTE-A), LTE-A Pro, and/or 5G New Radio (NR).

For convenience of description, implementations of the present disclosure are mainly described in regards to a 3GPP based wireless communication system. However, the technical features of the present 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 present disclosure that are not limited to 3GPP based wireless communication system are applicable to other mobile communication systems.

For terms and technologies which are not specifically described among the terms of and technologies employed in the present disclosure, the wireless communication standard documents published before the present disclosure may be referenced.

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

In the present disclosure, slash (/) or comma (,) may mean "and/or". For example, "A/B" may mean "A and/or B". Accordingly, "A/B" may mean "only A", "only B", or "both A and B". For example, "A, B, C" may mean "A, B or C".

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

In addition, in the present disclosure, "at least one of A, B and C" may mean "only A", "only B", "only C", or "any combination of A, B and C". In addition, "at least one of A, B or C" or "at least one of A, B and/or C" may mean "at least one of A, B and C".

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

Technical features that are separately described in one drawing in the present disclosure may be implemented separately or simultaneously.

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

Hereinafter, the present disclosure will be described in more detail with reference to drawings. The same reference numerals in the following drawings and/or descriptions may refer to the same and/or corresponding hardware blocks, software blocks, and/or functional blocks unless otherwise indicated.

The 5G usage scenarios shown in FIG. 1 are only exemplary, and the technical features of the present disclosure can be applied to other 5G usage scenarios which are not shown in FIG. 1.

Three main requirement categories for 5G include (1) a category of enhanced Mobile BroadBand (eMBB), (2) a category of massive Machine Type Communication (mMTC), and (3) a category of Ultra-Reliable and Low Latency Communications (URLLC).

Referring to FIG. 1, the communication system 1 includes wireless devices 100a to 100f, Base Stations (BSs) 200, and a network 300. Although FIG. 1 illustrates a 5G network as an example of the network of the communication system 1, the implementations of the present disclosure are not limited to the 5G system, and can be applied to the future communication system beyond the 5G system.

The BSs 200 and the network 300 may be implemented as wireless devices and a specific wireless device may operate as a BS/network node with respect to other wireless devices.

The wireless devices 100a to 100f represent devices performing communication using Radio Access Technology (RAT) (e.g., 5G NR or LTE) and may be referred to as communication/radio/5G devices. The wireless devices 100a to 100f may include, without being limited to, a robot 100a, vehicles 100b-1 and 100b-2, an eXtended Reality (XR) device 100c, a hand-held device 100d, a home appliance 100e, an Internet-of-Things (IoT) device 100f, and an Artificial Intelligence (AI) device/server 400. For example, the vehicles may include a vehicle having a wireless communication function, an autonomous driving vehicle, and a vehicle capable of performing communication between vehicles. The vehicles may include an Unmanned Aerial Vehicle (UAV) (e.g., a drone). The XR device may include an Augmented Reality (AR)/Virtual Reality (VR)/Mixed Reality (MR) device and may be implemented in the form of a Head-Mounted Device (HMD), a Head-Up Display (HUD) mounted in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance device, a digital signage, a vehicle, a robot, etc. The hand-held device may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or a smartglasses), and a computer (e.g., a notebook). The home appliance may include a TV, a refrigerator, and a washing machine. The IoT device may include a sensor and a smartmeter.

In the present disclosure, the wireless devices 100a to 100f may be called User Equipments (UEs). A UE may include, for example, a cellular phone, a smartphone, a laptop computer, a digital broadcast terminal, a Personal Digital Assistant (PDA), a Portable Multimedia Player (PMP), a navigation system, a slate Personal Computer (PC), a tablet PC, an ultrabook, a vehicle, a vehicle having an autonomous traveling function, a connected car, an UAV, an AI module, a robot, an AR device, a VR device, an MR device, a hologram device, a public safety device, an MTC device, an IoT device, a medical device, a FinTech device (or a financial device), a security device, a weather/environment device, a device related to a 5G service, or a device related to a fourth industrial revolution field.

The wireless devices 100a to 100f may be connected to the network 300 via the BSs 200. An AI technology may be applied to the wireless devices 100a to 100f and the wireless devices 100a to 100f may be connected to the AI server 400 via the network 300. The network 300 may be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, and a beyond-5G network. Although the wireless devices 100a to 100f may communicate with each other through the BSs 200/network 300, the wireless devices 100a to 100f may perform direct communication (e.g., sidelink communication) with each other without passing through the BSs 200/network 300. For example, the vehicles 100b-1 and 100b-2 may perform direct communication (e.g., Vehicle-to-Vehicle (V2V)/Vehicle-to-everything (V2X) communication). The IoT device (e.g., a sensor) may perform direct communication with other IoT devices (e.g., sensors) or other wireless devices 100a to 100f.

Wireless communication/

connections

150a, 150b and 150c may be established between the wireless devices 100a to 100f and/or between wireless device 100a to 100f and BS 200 and/or between BSs 200. Herein, the wireless communication/connections may be established through various RATs (e.g., 5G NR) such as uplink/downlink communication 150a, sidelink communication (or Device-to-Device (D2D) communication) 150b, inter-base station communication 150c (e.g., relay, Integrated Access and Backhaul (IAB)), etc. The wireless devices 100a to 100f and the BSs 200/the wireless devices 100a to 100f may 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 may transmit/receive signals through various physical channels. To this end, at least a part of various configuration information configuring processes, various signal processing processes (e.g., channel encoding/decoding, modulation/demodulation, and resource mapping/de-mapping), and resource allocating processes, for transmitting/receiving radio signals, may be performed based on the various proposals of the present disclosure.

NR supports multiples numerologies (and/or multiple Sub-Carrier Spacings (SCS)) to support various 5G services. For example, if SCS is 15 kHz, wide area can be supported in traditional cellular bands, and if SCS is 30 kHz/60 kHz, dense-urban, lower latency, and wider carrier bandwidth can be supported. If SCS is 60 kHz or higher, bandwidths greater than 24.25 GHz can be supported to overcome phase noise.

The NR frequency band may be defined as two types of frequency range, i.e., Frequency Range 1 (FR1) and Frequency Range 2 (FR2). The numerical value of the frequency range may be changed. For example, the frequency ranges of the two types (FR1 and FR2) may be as shown in Table 1 below. For ease of explanation, in the frequency ranges used in the NR system, FR1 may mean "sub 6 GHz range", FR2 may mean "above 6 GHz range," and may be referred to as millimeter Wave (mmW).

Frequency Range designation	Corresponding frequency range	Subcarrier Spacing
FR1	450MHz - 6000MHz	15, 30, 60kHz
FR2	24250MHz - 52600MHz	60, 120, 240kHz

As mentioned above, the numerical value of the frequency range of the NR system may be changed. For example, FR1 may include a frequency band of 410MHz to 7125MHz as shown in Table 2 below. That is, FR1 may include a frequency band of 6GHz (or 5850, 5900, 5925 MHz, etc.) or more. For example, a frequency band of 6 GHz (or 5850, 5900, 5925 MHz, etc.) or more included in FR1 may include an unlicensed band. Unlicensed bands may be used for a variety of purposes, for example for communication for vehicles (e.g., autonomous driving).

Frequency Range designation	Corresponding frequency range	Subcarrier Spacing
FR1	410MHz - 7125MHz	15, 30, 60kHz
FR2	24250MHz - 52600MHz	60, 120, 240kHz

Here, the radio communication technologies implemented in the wireless devices in the present disclosure may include NarrowBand IoT (NB-IoT) technology for low-power communication as well as LTE, NR and 6G. For example, NB-IoT technology may be an example of Low Power Wide Area Network (LPWAN) technology, may be implemented in specifications such as LTE Cat NB1 and/or LTE Cat NB2, and may not be limited to the above-mentioned names. Additionally and/or alternatively, the radio communication technologies implemented in the wireless devices in the present disclosure may communicate based on LTE-M technology. For example, LTE-M technology may be an example of LPWAN technology and be called by various names such as enhanced MTC (eMTC). For example, LTE-M technology may be implemented in at least one of the 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 may not be limited to the above-mentioned names. Additionally and/or alternatively, the radio communication technologies implemented in the wireless devices in the present disclosure may include at least one of ZigBee, Bluetooth, and/or LPWAN which take into account low-power communication, and may not be limited to the above-mentioned names. For example, ZigBee technology may generate Personal Area Networks (PANs) associated with small/low-power digital communication based on various specifications such as IEEE 802.15.4 and may be called various names.

In FIG. 2, The first wireless device 100 and/or the second wireless device 200 may be implemented in various forms according to use cases/services. For example, {the first wireless device 100 and the second wireless device 200} may correspond to at least one of {the wireless device 100a to 100f and the BS 200}, {the wireless device 100a to 100f and the wireless device 100a to 100f} and/or {the BS 200 and the BS 200} of FIG. 1. The first wireless device 100 and/or the second wireless device 200 may be configured by various elements, devices/parts, and/or modules.

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

The processing chip 101 may include at least one processor, such a processor 102, and at least one memory, such as a memory 104. Additional and/or alternatively, the memory 104 may be placed outside of the processing chip 101.

The processor 102 may control the memory 104 and/or the transceiver 106 and may be adapted to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts described in the present disclosure. For example, the processor 102 may process information within the memory 104 to generate first information/signals and then transmit radio signals including the first information/signals through the transceiver 106. The processor 102 may receive radio signals including second information/signals through the transceiver 106 and then store information obtained by processing the second information/signals in the memory 104.

The memory 104 may be operably connectable to the processor 102. The memory 104 may store various types of information and/or instructions. The memory 104 may store a firmware and/or a software code 105 which implements codes, commands, and/or a set of commands 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 firmware and/or the software code 105 may implement instructions that, when executed by the processor 102, perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. For example, the firmware and/or the software code 105 may control the processor 102 to perform one or more protocols. For example, the firmware and/or the software code 105 may control the processor 102 to perform one or more layers of the radio interface protocol.

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

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

The processing chip 201 may include at least one processor, such a processor 202, and at least one memory, such as a memory 204. Additional and/or alternatively, the memory 204 may be placed outside of the processing chip 201.

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

The memory 204 may be operably connectable to the processor 202. The memory 204 may store various types of information and/or instructions. The memory 204 may store a firmware and/or a software code 205 which implements codes, commands, and/or a set of commands 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 firmware and/or the software code 205 may implement instructions that, when executed by the processor 202, perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. For example, the firmware and/or the software code 205 may control the processor 202 to perform one or more protocols. For example, the firmware and/or the software code 205 may control the processor 202 to perform one or more layers of the radio interface protocol.

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

Hereinafter, hardware elements of the

wireless devices

100 and 200 will be described more specifically. One or more protocol layers may be implemented by, without being limited to, one or

more processors

102 and 202. For example, the one or

more processors

102 and 202 may implement one or more layers (e.g., functional layers such as Physical (PHY) layer, Media Access Control (MAC) layer, Radio Link Control (RLC) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Resource Control (RRC) layer, and Service Data Adaptation Protocol (SDAP) layer). The one or

more processors

102 and 202 may generate one or more Protocol Data Units (PDUs), one or more Service Data Unit (SDUs), messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. The one or

more processors

102 and 202 may generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure and provide the generated signals to the one or

more transceivers

106 and 206. The one or

more processors

102 and 202 may receive the 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 present disclosure.

The one or

more processors

102 and 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. The one or

more processors

102 and 202 may 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) may be included in the one or

more processors

102 and 202. For example, the one or

more processors

102 and 202 may be configured by a set of a communication control processor, an Application Processor (AP), an Electronic Control Unit (ECU), a Central Processing Unit (CPU), a Graphic Processing Unit (GPU), and a memory control processor.

The one or

more memories

104 and 204 may be connected to the one or

more processors

102 and 202 and store various types of data, signals, messages, information, programs, code, instructions, and/or commands. The one or

more memories

104 and 204 may be configured by Random Access Memory (RAM), Dynamic RAM (DRAM), Read-Only Memory (ROM), electrically Erasable Programmable Read-Only Memory (EPROM), flash memory, volatile memory, non-volatile memory, hard drive, register, cash memory, computer-readable storage medium, and/or combinations thereof. The one or

more memories

104 and 204 may be located at the interior and/or exterior of the one or

more processors

102 and 202. The one or

more memories

104 and 204 may be connected to the one or

more processors

102 and 202 through various technologies such as wired or wireless connection.

The one or

more transceivers

106 and 206 may 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 devices. The one or

more transceivers

106 and 206 may 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 devices. For example, the one or

more transceivers

106 and 206 may 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 may perform control so that the one or

more transceivers

106 and 206 may transmit user data, control information, or radio signals to one or more other devices. The one or

more processors

102 and 202 may perform control so that the one or

more transceivers

106 and 206 may receive user data, control information, or radio signals from one or more other devices.

The one or

more transceivers

106 and 206 may be connected to the one or

more antennas

108 and 208. Additionally and/or alternatively, the one or

more transceivers

106 and 206 may include one or

more antennas

108 and 208. The one or

more transceivers

106 and 206 may be adapted 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 may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports).

The one or

more transceivers

106 and 206 may convert received user data, control information, radio signals/channels, etc., from RF band signals into baseband signals in order to process received user data, control information, radio signals/channels, etc., using the one or

more processors

102 and 202. The one or

more transceivers

106 and 206 may convert the user data, control information, radio signals/channels, etc., processed using the one or

more processors

102 and 202 from the base band signals into the RF band signals. To this end, the one or

more transceivers

106 and 206 may 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 the carrier frequency. The one or

more transceivers

106 and 206 may receive OFDM signals at a carrier frequency and down-convert the OFDM signals into OFDM baseband signals by their (analog) oscillators and/or filters under the control of the one or

more processors

102 and 202.

Although not shown in FIG. 2, the

wireless devices

100 and 200 may further include additional components. The additional components 140 may be variously configured according to types of the

wireless devices

100 and 200. For example, the additional components 140 may include at least one of a power unit/battery, an Input/Output (I/O) device (e.g., audio I/O port, video I/O port), a driving device, and a computing device. The additional components 140 may be coupled to the one or

more processors

102 and 202 via various technologies, such as a wired or wireless connection.

In the implementations of the present disclosure, a UE may operate as a transmitting device in Uplink (UL) and as a receiving device in Downlink (DL). In the implementations of the present disclosure, a BS may operate as a receiving device in UL and as a transmitting device in DL. Hereinafter, for convenience of description, it is mainly assumed that the first wireless device 100 acts as the UE, and the second wireless device 200 acts as the BS. For example, the processor(s) 102 connected to, mounted on or launched in the first wireless device 100 may be adapted to perform the UE behavior according to an implementation of the present disclosure or control the transceiver(s) 106 to perform the UE behavior according to an implementation of the present disclosure. The processor(s) 202 connected to, mounted on or launched in the second wireless device 200 may be adapted to perform the BS behavior according to an implementation of the present disclosure or control the transceiver(s) 206 to perform the BS behavior according to an implementation of the present disclosure.

In the present disclosure, a BS is also referred to as a node B (NB), an eNode B (eNB), or a gNB.

Referring to FIG. 3, a UE 100 may correspond to the first wireless device 100 of FIG. 2.

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

The processor 102 may be adapted to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. The processor 102 may be adapted 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 may be implemented in the processor 102. The processor 102 may include ASIC, other chipset, logic circuit and/or data processing device. The processor 102 may be an application processor. The processor 102 may include at least one of DSP, CPU, GPU, a modem (modulator and demodulator). An example of the processor 102 may be found in SNAPDRAGON^TM series of processors made by Qualcomm^®, EXYNOS^TM series of processors made by Samsung^®, A series of processors made by Apple^®, HELIO^TM series of processors made by MediaTek^®, ATOM^TM series of processors made by Intel^® or a corresponding next generation processor.

The memory 104 is operatively coupled with the processor 102 and stores a variety of information to operate the processor 102. The memory 104 may include ROM, RAM, flash memory, memory card, storage medium and/or other storage device. When the embodiments are implemented in software, the techniques described herein can be implemented with modules (e.g., procedures, functions, etc.) that perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed in the present disclosure. The modules can be stored in the memory 104 and executed by the processor 102. The memory 104 can be implemented within 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.

The transceiver 106 is operatively coupled with the processor 102, and transmits and/or receives a radio signal. The transceiver 106 includes a transmitter and a receiver. The transceiver 106 may include baseband circuitry to process radio frequency signals. The transceiver 106 controls the one or more antennas 108 to transmit and/or receive a radio signal.

The power management module 141 manages power for the processor 102 and/or the transceiver 106. The battery 142 supplies power to the power management module 141.

The display 143 outputs results processed by the processor 102. The keypad 144 receives inputs to be used by the processor 102. The keypad 144 may be shown on the display 143.

The SIM card 145 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.

The speaker 146 outputs sound-related results processed by the processor 102. The microphone 147 receives sound-related inputs to be used by the processor 102.

The 5G system (5GS) architecture consists of the following network functions (NF).

- Authentication Server Function (AUSF)

- Access and Mobility Management Function (AMF)

- Data Network (DN), e.g., operator services, Internet access or 3rd party services

- Unstructured Data Storage Function (UDSF)

- Network Exposure Function (NEF)

- Intermediate NEF (I-NEF)

- Network Repository Function (NRF)

- Network Slice Selection Function (NSSF)

- Policy Control Function (PCF)

- Session Management Function (SMF)

- Unified Data Management (UDM)

- Unified Data Repository (UDR)

- User Plane Function (UPF)

- UE radio Capability Management Function (UCMF)

- Application Function (AF)

- User Equipment (UE)

- (Radio) Access Network ((R)AN)

- 5G-Equipment Identity Register (5G-EIR)

- Network Data Analytics Function (NWDAF)

- CHarging Function (CHF)

Furthermore, the following network functions may be considered.

- Non-3GPP InterWorking Function (N3IWF)

- Trusted Non-3GPP Gateway Function (TNGF)

- Wireline Access Gateway Function (W-AGF)

FIG. 4 depicts the 5G system architecture in the non-roaming case, using the reference point representation showing how various network functions interact with each other.

In FIG. 4, for the sake of clarity of the point-to-point diagrams, the UDSF, NEF and NRF have not been depicted. However, all depicted Network Functions can interact with the UDSF, UDR, NEF and NRF as necessary.

For clarity, the UDR and its connections with other NFs, e.g., PCF, are not depicted in FIG. 4. For clarity, the NWDAF and its connections with other NFs, e.g., PCF, are not depicted in FIG. 4.

The 5G system architecture contains the following reference points:

- N1: Reference point between the UE and the AMF.

- N2: Reference point between the (R)AN and the AMF.

- N3: Reference point between the (R)AN and the UPF.

- N4: Reference point between the SMF and the UPF.

- N6: Reference point between the UPF and a Data Network.

- N9: Reference point between two UPFs.

The following reference points show the interactions that exist between the NF services in the NFs.

- N5: Reference point between the PCF and an AF.

- N7: Reference point between the SMF and the PCF.

- N8: Reference point between the UDM and the AMF.

- N10: Reference point between the UDM and the SMF.

- N11: Reference point between the AMF and the SMF.

- N12: Reference point between the AMF and the AUSF.

- N13: Reference point between the UDM and the AUSF.

- N14: Reference point between two AMFs.

- N15: Reference point between the PCF and the AMF in the case of non-roaming scenario, PCF in the visited network and AMF in the case of roaming scenario.

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

- N22: Reference point between the AMF and the NSSF.

In some cases, a couple of NFs may need to be associated with each other to serve a UE.

A registration procedure is described. Section 4.2.2.2 of 3GPP TS 23.502 V16.3.0 (2019-12) can be referred.

A UE needs to register with the network to get authorized to receive services, to enable mobility tracking and to enable reachability. The UE initiates the registration procedure using one of the following registration types:

- Initial registration to the 5GS; or

- Mobility registration update; or

- Periodic registration update; or

- Emergency registration.

The general registration procedure in FIGS. 5 and 6 applies on all these registration procedures, but the periodic registration update need not include all parameters that are used in other registration cases.

The general registration procedure in FIGS. 5 and 6 is also used for the case of registration in 3GPP access when the UE is already registered in a non-3GPP access, and vice versa. Registration in 3GPP access when the UE is already registered in a non-3GPP access scenario may require an AMF change.

First, procedures of FIG. 6 are described.

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

The Registration Request message may include AN parameters. In the case of NG-RAN, the AN parameters include, e.g., 5G SAE temporary mobile subscriber identity (5G-S-TMSI) or globally unique AMF ID (GUAMI), the selected public land mobile network (PLMN) ID (or PLMN ID and network identifier (NID)) and Requested network slice selection assistance information (NSSAI). The AN parameters also include establishment cause. The establishment cause provides the reason for requesting the establishment of an RRC connection. Whether and how the UE includes the Requested NSSAI as part of the AN parameters is dependent on the value of the access stratum connection establishment NSSAI inclusion mode parameter.

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

When the UE is performing an initial registration, the UE shall indicate its UE identity in the Registration Request message as follows, listed in decreasing order of preference:

i) a 5G globally unique temporary identifier (5G-GUTI) mapped from an evolved packet system (EPS) GUTI, if the UE has a valid EPS GUTI.

ii) a native 5G-GUTI assigned by the PLMN to which the UE is attempting to register, if available;

iii) a native 5G-GUTI assigned by an equivalent PLMN to the PLMN to which the UE is attempting to register, if available;

iv) a native 5G-GUTI assigned by any other PLMN, if available.

v) Otherwise, the UE shall include its subscriber concealed identifier (SUCI) in the Registration Request message.

When the UE performing an initial registration has both a valid EPS GUTI and a native 5G-GUTI, the UE shall also indicate the native 5G-GUTI as additional GUTI. If more than one native 5G-GUTIs are available, the UE shall select the 5G-GUTI in decreasing order of preference among items (ii)-(iv) in the list above.

When the UE is performing an initial registration with a native 5G-GUTI, then the UE shall indicate the related GUAMI information in the AN parameters. When the UE is performing an initial registration with its SUCI, the UE shall not indicate any GUAMI information in the AN parameters.

For an emergency registration, the SUCI shall be included if the UE does not have a valid 5G-GUTI available; the permanent equipment identifier (PEI) shall be included when the UE has no subscriber permanent identifier (SUPI) and no valid 5G-GUTI. In other cases, the 5G-GUTI is included and it indicates the last serving AMF.

The Registration Request message may also include security parameters, PDU Session Status, etc. The security parameters are used for authentication and integrity protection. The PDU Session Status indicates the previously established PDU sessions in the UE. When the UE is connected to the two AMFs belonging to different PLMN via 3GPP access and non-3GPP access then the PDU Session status indicates the established PDU Session of the current PLMN in the UE.

(2) Step 2: The (R)AN selects an AMF.

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

If UE is in CM-CONNECTED state, the (R)AN can forward the Registration Request message to the AMF based on the N2 connection of the UE.

If the (R)AN cannot select an appropriate AMF, it forwards the Registration Request message to an AMF which has been configured, in the (R)AN, to perform AMF selection.

(3) Step 3: The (R)AN transmits a Registration Request message to the new AMF. The Registration Request message corresponds to N2 message.

The Registration Request message may include whole information and/or a part of information included in the Registration Request message received from the UE which is described in step 1.

The Registration Request message may include N2 parameters. When NG-RAN is used, the N2 parameters include the selected PLMN ID (or PLMN ID and NID), location information and cell identity related to the cell in which the UE is camping, UE context request which indicates that a UE context including security information needs to be setup at the NG-RAN. When NG-RAN is used, the N2 parameters shall also include the establishment cause.

If the Registration type indicated by the UE is Periodic Registration Update, then steps 4 to 19 may be omitted.

(4) Step 4: If the UE's 5G-GUTI was included in the Registration Request message and the serving AMF has changed since last registration procedure, the new AMF may invoke the Namf_Communication_UEContextTransfer service operation on the old AMF including the complete registration request non-access stratum (NAS) message to request the UE's SUPI and UE context.

(5) Step 5: The Old AMF may respond to the new AMF for the Namf_Communication_UEContextTransfer invocation by including the UE's SUPI and UE context.

(6) Step 6: If the SUCI is not provided by the UE nor retrieved from the old AMF, the identity request procedure may be initiated by the new AMF sending the Identity Request message to the UE requesting the SUCI.

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

(8) Step 8: The new AMF may decide to initiate UE authentication by invoking an AUSF. In that case, the new AMF selects an AUSF based on SUPI or SUCI.

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

(10) Step 10: If the AMF has changed, the new AMF may notify the old AMF that the registration of the UE in the new AMF is completed by invoking the Namf_Communication_RegistrationCompleteNotify service operation. If the authentication/security procedure fails, then the registration shall be rejected, and the new AMF may invoke the Namf_Communication_RegistrationCompleteNotify service operation with a reject indication reason code towards the old AMF. The old AMF may continue as if the UE context transfer service operation was never received.

(11) Step 11: If the PEI was not provided by the UE nor retrieved from the old AMF, the Identity Request procedure may be initiated by the new AMF sending an Identity Request message to the UE to retrieve the PEI. The PEI shall be transferred encrypted unless the UE performs emergency registration and cannot be authenticated.

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

Now, procedures of FIG. 6, which follow the procedures of FIG. 5, are described.

(13) Step 13: If step 14 below is to be performed, the new AMF, based on the SUPI, may select a UDM, then UDM may select a UDR instance.

(14) Step 14: The new AMF may register with the UDM.

(15) Step 15: The new AMF may select a PCF.

(16) Step 16: The new AMF may optionally perform an AM Policy Association Establishment/Modification.

(17) Step 17: The new AMF may transmit Update/Release SM Context message (e.g., Nsmf_PDUSession_UpdateSMContext and/or Nsmf_PDUSession_ReleaseSMContext) to the SMF.

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

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

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

(21) Step 21: The new AMF transmits a Registration Accept message to the UE.

The new AMF sends a Registration Accept message to the UE indicating that the Registration Request has been accepted. 5G-GUTI is included if the new AMF allocates a new 5G-GUTI. If the UE is already in 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 no 5G-GUTI is included in the Registration Accept message, then the UE uses the 5G-GUTI assigned for the existing registration also for the new registration. If the new AMF allocates a new registration area, it shall send the registration area to the UE via Registration Accept message. If there is no registration area included in the Registration Accept message, the UE shall consider the old registration area as valid. Mobility Restrictions is included in case mobility restrictions applies for the UE and registration type is not emergency registration. The new AMF indicates the established PDU sessions to the UE in the PDU Session status. The UE removes locally 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 the two AMFs belonging to different PLMN via 3GPP access and non-3GPP access then the UE removes locally any internal resources related to the PDU session of the current PLMN that are not marked as established in received PDU Session status. If the PDU Session status information was in the Registration Request message, the new AMF shall indicate the PDU Session status to the UE.

The Allowed NSSAI provided in the Registration Accept message is valid in the registration area and it applies for all the PLMNs which have their tracking areas included in the registration area. The Mapping Of Allowed NSSAI is the mapping of each Single Network Slice Selection Assistance Information (S-NSSAI) of the Allowed NSSAI to the HPLMN S-NSSAIs. The Mapping Of Configured NSSAI is the mapping of each S-NSSAI of the Configured NSSAI for the serving PLMN to the HPLMN S-NSSAIs.

Furthermore, optionally the new AMF performs a UE Policy Association Establishment.

(22) Step 22: The UE may send a Registration Complete message to the new AMF when it has successfully updated itself.

The UE may send a Registration Complete message to the new AMF to acknowledge if a new 5G-GUTI was assigned.

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

(24) Step 24: The new AMF may perform information update towards the UDM.

(25) Step 25: The UE may execute Network Slice-Specific Authentication and Authorization procedure.

<Network Slice>

Hereinafter, network slicing to be introduced in next-generation mobile communication will be described.

Next-generation mobile communication introduces the concept of network slicing in order to provide various services through one network. Here, the network slicing is a combination of network nodes having functions necessary to provide a specific service. A network node constituting a slice instance may be a hardware independent node or a logically independent node.

Each slice instance may be composed of a combination of all nodes necessary to configure the entire network. In this case, one slice instance may independently provide a service to the UE.

Alternatively, the slice instance may be composed of a combination of some nodes among nodes constituting the network. In this case, the slice instance may not provide a service to the UE alone, but may provide a service to the UE in association with other existing network nodes. In addition, a plurality of slice instances may provide a service to the UE in association with each other.

A slice instance is different from a dedicated core network in that the entire network node including the Core Network (CN) node and the RAN can be separated. In addition, a slice instance is different from a dedicated core network in that network nodes can simply be logically separated.

For reference, for a network slice, quota may be used.

For example, a quota related to a network slice may include a quota for the maximum number of UEs. The quota for the maximum number of UEs may mean the maximum number of terminals that can use a network slice at the same time. As an example, each network slice information may include quota information for the maximum number of UEs (e.g., 10 pieces, 1000000 pieces, etc.).

For example, a quota related to a network slice may include a quota for the maximum number of PDU sessions. The quota for the maximum number of PDU sessions may mean the maximum number of concurrent PDU sessions supported in the network slice. For example, the maximum number of concurrent (concurrent) PDU sessions supported in a network slice may mean the maximum number of PDU sessions established at the same time in one network slice related to a DNN (Data Network Name) defined by S-NSSAI.

In 5G mobile communication, network slice quota event notification may be supported in the network slice. For example, event notification about a quota related to a network slice may be supported. For example, an AF may request an event notification about a quota related to a network slice in 5GS. Then, AF may be notified of quota for attributes related to network slices in 5GS. For example, 5GS may inform the AF whether the quota for a particular attribute has reached a specified threshold. AF may then influence the 5GS routing decision.

FIG. 7 is an exemplary diagram illustrating an example of an architecture for implementing the concept of network slicing.

As can be seen with reference to FIG. 7, the Core Network (CN) may be divided into several slice instances. Each slice instance may include one or more of a CP function node and a UP function node.

Each UE may use a network slice instance suitable for its own service through the RAN.

Unlike shown in FIG. 7, each slice instance may share one or more of a CP function node and a UP function node with another slice instance. This will be described with reference to FIG. 8 as follows.

FIG. 8 is an exemplary diagram illustrating another example of an architecture for implementing the concept of network slicing.

Referring to FIG. 8, a plurality of UP functional nodes is clustered, and similarly, a plurality of CP functional nodes is also clustered.

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

The illustrated NSSF selects a slice (or instance) that can accommodate the service of the UE.

The illustrated UE may use service #1 through the slice instance #1 selected by the NSSF, and may use service #2 through the slice instance #2 selected by the NSSF.

A PDU session establishment procedure is described. Section 4.3.2 of 3GPP TS 23.502 V16.3.0 (2019-12) can be referred.

FIGS. 9 and 10 show an example of a PDU session establishment procedure to which implementations of the present disclosure is applied.

A PDU session establishment may correspond to:

- a UE initiated PDU session establishment procedure.

- a UE initiated PDU session handover between 3GPP and non-3GPP.

- a UE initiated PDU session handover from EPS to 5GS.

- a network triggered PDU session establishment procedure.

A PDU session may be associated either (a) with a single access type at a given time, i.e., either 3GPP access or non-3GPP access, or (b) simultaneously with multiple access types, i.e., one 3GPP access and one non-3GPP access. A PDU session associated with multiple access types is referred to as multi access PDU (MA PDU) session and it may be requested by access traffic steering, switching, splitting (ATSSS)-capable UEs.

FIGS. 9 and 10 specify the procedures for establishing PDU sessions associated with a single access type at a given time.

The procedure shown in FIGS. 9 and 10 assumes that the UE has already registered on the AMF thus unless the UE is emergency registered the AMF has already retrieved the user subscription data from the UDM.

First, procedures of FIG. 9 are described.

(1) Step 1: In order to establish a new PDU session, the UE generates a new PDU session ID.

The UE initiates the UE requested PDU session establishment procedure by the transmission of a NAS message containing a PDU Session Establishment Request message within the N1 SM container. The PDU Session Establishment Request message includes a PDU session ID, Requested PDU Session Type, a Requested session and service continuity (SSC) mode, 5GSM Capability, protocol configuration options (PCO), SM PDU DN Request Container, UE Integrity Protection Maximum Data Rate, etc.

The Request Type indicates "Initial request" if the PDU session establishment is a request to establish a new PDU session and indicates "Existing PDU Session" if the request refers to an existing PDU session switching between 3GPP access and non-3GPP access or to a PDU session handover from an existing packet data network (PDN) connection in EPC. The Request Type indicates "Emergency Request" if the PDU session establishment is a request to establish a PDU session for emergency services. The Request Type indicates "Existing Emergency PDU Session" if the request refers to an existing PDU session for emergency services switching between 3GPP access and non-3GPP access or to a PDU session handover from an existing PDN connection for emergency services in EPC.

The UE includes the S-NSSAI from the Allowed NSSAI of the current access type. If the Mapping of Allowed NSSAI was provided to the UE, the UE shall provide both the S-NSSAI of the visited PLMN (VPLMN) from the Allowed NSSAI and the corresponding S-NSSAI of the HPLMN from the Mapping Of Allowed NSSAI.

(2) Step 2: The AMF selects an SMF. If the Request Type indicates "Initial request" or the request is due to handover from EPS or from non-3GPP access serving by a different AMF, the AMF stores an association of the S-NSSAI(s), the data network name (DNN), the PDU session ID, the SMF ID as well as the Access Type of the PDU session.

If the Request Type is "initial request" and if the Old PDU session ID indicating the existing PDU session is also contained in the message, the AMF selects an SMF and stores an association of the new PDU Session ID, the S-NSSAI(s), the selected SMF ID as well as Access Type of the PDU Session.

If the Request Type indicates "Existing PDU Session", the AMF selects the SMF based on SMF-ID received from UDM. The AMF updates the Access Type stored for the PDU session.

If the Request Type indicates "Existing PDU Session" referring to an existing PDU session moved between 3GPP access and non-3GPP access, then if the serving PLMN S-NSSAI of the PDU session is present in the Allowed NSSAI of the target access type, the PDU session establishment procedure can be performed in the following cases:

- the SMF ID corresponding to the PDU session ID and the AMF belong to the same PLMN;

- the SMF ID corresponding to the PDU session ID belongs to the HPLMN;

Otherwise the AMF shall reject the PDU session establishment request with an appropriate reject cause.

The AMF shall reject a request coming from an emergency registered UE and the Request Type indicates neither "Emergency Request" nor "Existing Emergency PDU Session".

(3) Step 3: If the AMF does not have an association with an SMF for the PDU session ID provided by the UE (e.g., when Request Type indicates "initial request"), the AMF invokes Create SM Context Request procedure (e.g., Nsmf_PDUSession_CreateSMContext Request). If the AMF already has an association with an SMF for the PDU session ID provided by the UE (e.g., when Request Type indicates "existing PDU Session"), the AMF invokes Update SM Context Request procedure (e.g., Nsmf_PDUSession_UpdateSMContext Request).

The AMF sends the S-NSSAI of the serving PLMN from the Allowed NSSAI to the SMF. For roaming scenario in local breakout (LBO), the AMF also sends the corresponding S-NSSAI of the HPLMN from the Mapping Of Allowed NSSAI to the SMF.

The AMF ID is the UE's GUAMI 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 message received from the UE. The generic public subscription identifier (GPSI) shall be included if available at AMF.

The AMF provides the PEI instead of the SUPI when the UE in limited service state has registered for emergency services without providing a SUPI. In case the UE in limited service state has registered for Emergency services with a SUPI but has not been authenticated, the AMF indicates that the SUPI has not been authenticated. The SMF determines that the UE has not been authenticated when it does not receive a SUPI for the UE or when the AMF indicates that the SUPI has not been authenticated.

The AMF may include a PCF ID in the Nsmf_PDUSession_CreateSMContext Request. This PCF ID identifies the home PCF (H-PCF) in the non-roaming case and the visited PCF (V-PCF) in the LBO roaming case.

(4) Step 4: If session management subscription data for corresponding SUPI, DNN and S-NSSAI of the HPLMN is not available, then SMF may retrieve the session management subscription data from the UDM and subscribes to be notified when this subscription data is modified.

(5) Step 5: The SMF transmits either Create SM Context Response message (e.g., Nsmf_PDUSession_CreateSMContext Response) or Update SM Context Response message (e.g., Nsmf_PDUSession_UpdateSMContext Response) to the AMF, depending on the request received in step 3.

If the SMF received Nsmf_PDUSession_CreateSMContext Request in step 3 and the SMF is able to process the PDU session establishment request, the SMF creates an SM context and responds to the AMF by providing an SM Context ID.

When the SMF decides to not accept to establish a PDU session, the SMF rejects the UE request via NAS SM signaling including a relevant SM rejection cause by responding to the AMF with 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 below and the PDU session establishment procedure is stopped.

(6) Step 6: Optional secondary authentication/authorization may be performed.

(7a) Step 7a: If dynamic policy and charging control (PCC) is to be used for the PDU session, the SMF may perform PCF selection.

(7b) Step 7b: The SMF may perform an SM Policy Association Establishment procedure to establish an SM Policy association with the PCF and get the default PCC rules for the PDU session.

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

(9) Step 9: The SMF may perform an SMF initiated SM Policy Association Modification procedure to provide information on the policy control request trigger condition(s) that have been met.

(10) Step 10: If Request Type indicates "initial request", the SMF may initiate an N4 Session Establishment procedure with the selected UPF. Otherwise, the SMF may initiate an N4 Session Modification procedure with the selected UPF

In step 10a, the SMF may send an N4 Session Establishment/Modification Request to the UPF and provides packet detection, enforcement and reporting rules to be installed on the UPF for this PDU session. In step 10b, the UPF may acknowledge by sending an N4 Session Establishment/Modification Response.

(11) Step 11: The SMF transmits a N1N2Message Transfer message (e.g., Namf_Communication_N1N2MessageTransfer) to the AMF.

The N1N2Message Transfer message may include N2 SM information. The N2 SM information carries information that the AMF shall forward to the (R)AN which may include:

- The CN Tunnel Info: Core network address(es) of the N3 tunnel corresponding to the PDU session;

- One or multiple quality of service (QoS) profiles and the corresponding QoS flow IDs (QFIs);

- The PDU session ID: indicate to the UE the association between (R)AN resources and a PDU session for the UE.

- S-NSSAI with the value for the serving PLMN (i.e., the HPLMN S-NSSAI or, in LBO roaming case, the VPLMN S-NSSAI).

- User Plane Security Enforcement information determined by the SMF.

- If the User Plane Security Enforcement information indicates that integrity protection is "Preferred" or "Required", the SMF also includes the UE Integrity Protection Maximum Data Rate as received in the PDU Session Establishment Request message.

- Redundancy sequence number (RSN) parameter

The N1N2Message Transfer message may include N1 SM container. The N1 SM container contains the PDU Session Establishment Accept message that the AMF shall provide to the UE. The PDU Session Establishment Accept message includes S-NSSAI from the Allowed NSSAI. For LBO roaming scenario, the PDU Session Establishment Accept message includes the S-NSSAI from the Allowed NSSAI for the VPLMN and also it includes the corresponding S-NSSAI of the HPLMN from the Mapping Of Allowed NSSAI that SMF received in step 3.

Multiple QoS Rules, QoS flow level, QoS parameters if needed for the QoS Flow(s) associated with those QoS rule(s) and QoS Profiles may be included in the PDU Session Establishment Accept message within the N1 SM container and in the N2 SM information.

If the PDU session establishment failed anywhere between step 5 and step 11, then the N1N2Message Transfer message shall include the N1 SM container with a PDU Session Establishment Reject message and shall not include any N2 SM information. The (R)AN sends the NAS message containing the PDU Session Establishment Reject message to the UE. In this case, steps 12-17 are skipped.

(12) Step 12: The AMF sends the NAS message containing PDU Session ID and PDU Session Establishment Accept message targeted to the UE and the N2 SM information received from the SMF within the N2 PDU Session Request message to the (R)AN.

(13) Step 13: The (R)AN may issue AN specific signaling exchange with the UE that is related with the information received from SMF. For example, in case of a NG-RAN, an RRC connection reconfiguration may take place with the UE establishing the necessary NG-RAN resources related to the QoS rules for the PDU session request received in step 12.

The (R)AN forwards the NAS message (PDU Session ID, N1 SM container (PDU Session Establishment Accept message)) provided in step 12 to the UE. The (R)AN shall only provide the NAS message to the UE if the AN specific signaling exchange with the UE includes the (R)AN resource additions associated to the received N2 command.

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

Now, procedures of FIG. 10, which follow the procedures of FIG. 9, are described.

(14) Step 14: The (R)AN transmits a N2 PDU Session Response message to the AMF. The N2 PDU Session Response message may include PDU session ID, Cause, N2 SM information (PDU Session ID, AN Tunnel Info, List of accepted/rejected QFI(s), User Plane Enforcement Policy Notification)), etc.

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

(16a) Step S16a: The SMF initiates an N4 Session Modification procedure with the UPF. The SMF provides AN Tunnel Info to the UPF as well as the corresponding forwarding rules.

(16b) Step S16b: The UPF provides an N4 Session Modification Response to the SMF.

After this step, the UPF may deliver any DL packets to the UE that may have been buffered for this PDU session.

(16c) Step 16c: If the SMF has not yet registered for this PDU session, then the SMF may register with the UDM for a given PDU Session.

(17) Step 17: The SMF transmits an Update SM Context Response message (e.g., Nsmf_PDUSession_UpdateSMContext Response) to the AMF.

After this step, the AMF forwards relevant events subscribed by the SMF.

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

(19) Step 19: In the case of PDU Session Type IPv6 or IPv4v6, the SMF may generate an IPv6 Router Advertisement and send it to the UE.

(20) Step 20: The SMF may perform SMF initiated SM Policy Association Modification.

(21) Step 21: If the PDU Session establishment failed after step 4, the SMF may unsubscribe to the modifications of session management subscription data, if the SMF is no more handling a PDU session of the UE.

Steering of Roaming (SOR): A technique whereby a roaming UE is encouraged to roam to a preferred roamed-to-network indicated by the HPLMN.

Steering of Roaming application function (SOR-AF): An application function that can provide UDM with one of the following:

a) one or more of the following:

- list of preferred PLMN/access technology combinations;

- SOR-CMCI, together with the "Store SOR-CMCI in ME" indicator if applicable;

- SOR-SNPN-SI;

b) a secured packet, together with the indicator, if applicable, that "the list of preferred PLMN/access technology combinations is not included in the secured packet"; or

c) neither of a) or b),

generated dynamically based on operator specific data analytics solutions.

Steering of Roaming information: This consists of the following HPLMN or subscribed SNPN protected information (see 3GPP TS 33.501 V18.0.0):

a) the following indicators, of whether:

- the UDM requests an acknowledgement from the UE for successful reception of the steering of roaming information.

- the UDM requests the UE to store the SOR-CMCI in the ME, which is provided along with the SOR-CMCI in plain text; and

b) one of the following:

1) one or more of the following:

- list of preferred PLMN/access technology combinations with an indication that it is included;

- SOR-CMCI; or

- SOR-SNPN-SI;

2) a secured packet with an indication that it is included;

3) the HPLMN indication that 'no change of the "Operator Controlled PLMN Selector with Access Technology" list stored in the UE is needed and thus no list of preferred PLMN/access technology combinations is provided'; or

4) the subscribed SNPN or HPLMN indication that 'no change of the SOR-SNPN-SI stored in the UE is needed and thus no SOR-SNPN-SI is provided'.

Steering of roaming connected mode control information (SOR-CMCI): HPLMN information to control the timing for a UE in connected mode to move to idle mode in order to perform steering of roaming.

Steering of roaming SNPN selection information (SOR-SNPN-SI): Provisioning information for SNPN selection consisting of:

a) the credentials holder controlled prioritized list of preferred SNPNs;

b) the credentials holder controlled prioritized list of Group ID for Network Selection (GIN)s ; or

c) both of the above.

Examples related to Control plane solution for steering of roaming in 5GS are explained.

For exmaple, UE configuration and subscription aspects are exaplained.

An Standalone Non-Public Network (SNPN)-enabled UE may be configured with the following information for each subscribed SNPN:

- PLMN ID and NID of the subscribed SNPN;

- Subscription identifier (SUPI) and credentials for the subscribed SNPN;

- Optionally, an N3IWF FQDN and an identifier of the country where the configured N3IWF is located;

- Optionally, if the UE supports access to an SNPN using credentials from a Credentials Holder, the UE is configured with one or more among a to c:

- a) User controlled prioritized list of preferred SNPNs;

- b) Credentials Holder controlled prioritized list of preferred SNPNs;

- c) Credentials Holder controlled prioritized list of GINs.

- Protection scheme for concealing the SUPI as defined in TS　33.501 V17.8.0;

For an SNPN-enabled UE with SNPN subscription, the Credentials Holder controlled prioritized lists of preferred SNPNs and GINs may be updated by the Credentials Holder using the Steering of Roaming (SoR) procedure as defined in Annex　C of TS　23.122 V17.7.0　. Updating Credentials Holder controlled prioritized lists of preferred SNPNs and GINs via the Steering of Roaming (SoR) procedure is not applicable for Credentials Holder with AAA Server.

A subscription of an SNPN may be either:

- identified by a SUPI containing a network-specific identifier that takes the form of a Network Access Identifier (NAI) using the NAI RFC 7542　based user identification as defined in clause　28.7.2 of TS　23.003 V17.7.0. The realm part of the NAI may include the NID of the SNPN; or

- identified by a SUPI containing an IMSI.

In the case of access to an SNPN using credentials owned by a Credentials Holder as specified in clause　5.30.2.9.2 and clause　5.30.2.9.3 of TS 23.501 V18.0.0, the SUPI may also contain identification for the Credentials Holder (i.e. the realm in the case of Network Specific Identifier based SUPI or the MCC and MNC in the case of an IMSI based SUPI). In the case of access to an SNPN using credentials owned by a Credentials Holder using AAA-S as specified in clause　5.30.2.9.2 of TS 23.501 V18.0.0, only Network Specific Identifier based SUPI is supported.

An SNPN-enabled UE that supports access to an SNPN using credentials from a Credentials Holder and that is equipped with a PLMN subscription may additionally be configured with the following information for SNPN selection and registration using the PLMN subscription in SNPN access mode:

- User controlled prioritized list of preferred SNPNs;

- Credentials Holder controlled prioritized list of preferred SNPNs;

- Credentials Holder controlled prioritized list of preferred GINs.

For an SNPN-enabled UE with PLMN subscription, the Credentials Holder controlled prioritized lists of preferred SNPNs and GINs may be updated by the Credentials Holder using the Steering of Roaming (SoR) procedure as defined in Annex　C of TS　23.122 V17.7.0.

When the Credentials Holder updates a UE with the Credentials Holder controlled prioritized lists of preferred SNPNs and GINs the UE may perform SNPN selection again, e.g. to potentially select a higher prioritized SNPN.

An on-demand S-NSSAI is defined to register the network slice associated with the user data only when the PDU session used to actually transmit the user data is established. If an on-demand S-NSSAI is configured, the network slice registration is performed during the PDU session establishment phase, not during the registration phase. If the slice registration is successful, the corresponding S-NSSAI can be managed as an allowed NSSAI. For example, if the inactivity timer associated with the S-NSSAI expires because there is no ongoing user data, the UE and the network may release the PDU session and manage the on-demand S-NSSAI as a not-allowed NSSAI.

Managing slices has become complex, with on-demand S-NSSAI settings, time/location validity settings for network slices, etc. However, previously, it was not possible to manage UE route selection policy (URSP)for on-demand S-NSSAI (e.g., checking URSP rule when triggering PDU session establishment). This can lead to delays in updating slice-related UE policies due to signaling overhead. For example, in the prior art, slice-related UE policy updates could not be performed immediately after each slice state change.

According to the present disclosure, when a UE attempts to use a network slice, if the UE does not have a valid UE policy for the slice, the UE may inform the network about this. According to the present disclosure, the real-time UE policy management overhead and signaling overhead of the network can be reduced.

The slice usage control mechanisms including UE slice usage control are being discussed. There are two main categories of the discussion topics.

For example, the first category is to control slice usage control as part of improved network control of the UE behaviour discussion. The second category is to improve the existing SoR (Steering of Roaming) mechanism to support slice aware PLMN selection.

Based on the SoR based slice aware PLMN selection, the UE may perform slice aware PLMN selection based on the PLMN priority provided by the network. However, more proactive solutions on the UE side needs to be investigated for the UE service quality.

For example, the UE behaviour to use or register a particular slice may be controlled by the network. The network may transmit slice validity time, slice validity location, on-demand only slice, slice usage deactivation time, etc, to the UE. When the allowed or configured slice in the area becomes unavailable due to the extra network control, it may cause the service limitation provided by the UE. It is because that it is impossible to exactly predict the user preference in the future.

For exmaple, on-demand S-NSSAI may be defined as the following. The on-demand S-NSSAI may be used for performing network slice registration and managing the network slice as an allowed NSSAI, when user data traffic exists.

On-demand S-NSSAI: An S-NSSAI that the UE is allowed to be registered with the network only when this S-NSSAI is used by the UE to establish a PDU session for user data transmission.

Based on the on-demand S-NSSAI, the network can determine the presence of user traffic and manage the PDU session. The UE knows that user traffic exists when it receives user traffic from the upper layers. If user traffic does not exist for a certain period of time. The UE may receive a PDU session release message from the network.

In TS 24.501 S5.15.15.3 Network-based per UE Network Slice usage behaviour control, examples related to the on-demand S-NSSAI are described.

The SMFs provide to UPFs that handle the PDU sessions in the Network Slice a PDU Session inactivity timer. The PDU Session inactivity timer is started after no data packet is transmitted or received and runs until the next data packet is transmitted or received which restarts the timer again. For example, the SMF may set the PDU session inactivity timer. The SMF may transmit a value related to the PDU session inactivity timer to the UPF. The UPF may start the PDU session inactivity timer, when the UPF detects that on-going user data packet related to a PDU session does not exist. If the PDU Session inactivity timer expires before any packet is received or transmitted, the UPF reports this PDU Session inactivity event to the SMF to cause the SMF to release the PDU Session. For example, the SMF may transmit PDU session release message to the UE. While releasing the PDU session the SMF may indicate the release cause because of slice inactivity. The AMF receives the notification of PDU Session release and it includes the release cause of slice inactivity and the Network Slice of the released PDU Session may not be used by other PDU Sessions (i.e. the last PDU Session using the Network Slice is released) over the corresponding access type. In this case, the AMF may trigger the UE Configuration Update procedure to remove the Network Slice from the Allowed NSSAI over that corresponding access type or start slice deregistration inactivity timer for the Network Slice.

According to the present disclosure, to implement the mechanism for a UE to provide the preferred/requested service associated with a particular slice(s), when the UE determines the slice unavailability(e.g., the UE may determine that the slice realted to the preferred/requested service is unavailable). The UE may proactively report the failure information to request the updated network slice configuration to the network.

For example, the request may be used by the UE in order to receive the update of URSP or UE configuration for network slice configuration from the network.

Upon reception of the UE report, the serving network(e.g., PCF of the serving network) may transmit the UE report information to the HPLMN and the UE policy (e.g., URSP) may be updated by the HPLMN(e.g., PCF of the HPLMN). If the UE request for the update fails or is unavailable, the UE may perform slice aware PLMN selection or slice aware cell (re)selection.

Example operations according to implementations of the present disclosure are as follows as presented in FIG. 11.

The following drawings are intended to illustrate specific embodiments of the present disclosure. The designations of specific devices or the designations of specific signals/messages/fields shown in the drawings are for illustrative purposes only, and the technical features of the present specification are not limited to the specific designations used in the drawings below.

FIG. 11 illustrates an example of operations according to an embodiment of the present disclosure.

In FIG. 11, the network may inclue AMF and PCF.

In step S1101, the UE may transmit registration request to the network. The registration request message may include UE capability information. The UE capability information may include that the UE supports UE slices usage control feature.The UE slice usage control feature may mean feature to support on-demand S-NSSAI. UE slices usage control feature supports operations related to on-demand S-NSSAI.

In step S1102, the UE may transmit indication that the UE supports UE report to the AMF and/or PCF.

In step S1103, the network (e.g., AMF) may transmit registration accept message to the UE. The registration accept message may include roaming assistant information. The roaming assistant information may include one or more among PLMN information, SNPN information, slice information, and validity time information related to a network slice.

In step S1104, the network (e.g, PCF) may transmit MANAGE UE POLICY COMMAND message to the UE. MANAGE UE POLICY COMMAND message may include UE slice usage control information.

In step S1105, the network may transmit UE Configuration Update message to the UE. UE Configuration Update message may include UE slice usage control information.

Note that only one of step 1104 and step 1105 may be performed. Or both steps can be skipped.

In step S1106, the UE may detect that a network slice is unavailable. For exmaple, the UE may detect that the preferred slice is unavailable.

In step S1107, the UE may determine a cause. For example, the UE may determine the cause why the preferred slice is unavailbe. For exmaple, the unavailable slice information may include one or more of network slice location validity information, information related to on-demand S-NSSAI, and network slice time validity information. The UE may store the cause. The UE may store UE policy information (e.g., UE policy section code (UPSC), Route Selection Descriptors (RSD), Policy version number). The PCF stores UE policies in the form of UE policy sections and manages them as a list of UE policy section identifiers (UPSI). A UPSI contains by default a PLMN ID and a UPSC. The PCF may manage the UPSC to be uniquely defined within a PLMN (or SNPN). The RSD may mean identifier related to transmit user traffic to which PDU session. The RSD may inlcude S-NSSAI, DNN type, PDU session type. The PCF may update policy based on whether the policy version number related to the policy is the latest version or not.

In step S1108, the UE may transmit UE report to the network(e.g,, to the AMF and/or the PCF). The UE report may include unavailable slice information. The unavailable slice information may include information related to the unavailable slice detected by the UE.

In step S1109, the UE may transmit UE policy state indication to the network(e.g,, to the AMF and/or the PCF). The UE policy state indication may include UE policy information and unavailable slice information. For example, UE policy information may include UPSI list.

In step S1110, the network may update configuration related to a network slice. For example, the network may update configuration (e.g., URSP, usages setting) related to the network slice based on the UE report.

In step S1111, the network(e.g,, the AMF and/or the PCF) may transmit MANAGE UE POLICY COMMAND message to the UE. MANAGE UE POLICY COMMAND message may include UE slice usage control information.

In step S1112, the network may transmit UE Configuration Update message to the UE. UE Configuration Update message may include slice information.

According to implementations of the present disclosure, the UE slice usage control information may include the validity information for network slice usage (e.g., validity time, geographical location, usage timer) or invalidity information (e.g., unavailable time, unavailable/forbidden location/cell/TA/RA/PLMN/SNPN, inactivity timer).

For example, the NW may transmit the UE slice usage control information to the UE via NAS signalling and/or AS signalling:

- For example, the UE may perform operations in the presetn disclosure based on the slice configuration or slice usage control information received via NAS signalling and/or AS signalling, and determines the unavailability of the preferred slice.

- The UE may receive the UE slice usage control information as URSP policy. For example, the PCF may transmit the UE slice usage control information as URSP policy to the UE.

- The UE may receive the UE slice usage control information via UE configuration update. For exmaple, the AMF may trasmit the UE slice usage control information via UE configuration update to the UE.

- The UE may receive the UE slice usage control information via SoR information from an AMF.

- The UE may receive the UE slice usage control information via SystemInformation from a base station.

- The UE may receive the UE slice usage control information via RRC signalling from the base station.

The UE may transmit information realted to UE report via NAS signalling and/or AS signalling to the NW. For example, the following examples are applied:

- The UE may transmit the UE report via UE STATE INDICATION to the PCF.

- The UE may transmit the UE report via Configuration update complete to the PCF or the AMF. For example, the UE may transmit the slice usage failure information stored in the UE if the UE has received Configuration update command and the usage failed slice is still unavailable according the latest UE configuration.

- The UE may transmit the UE report via RRC message used for logging information delivery to the base station(e.g., RAN node).

- The UE may transmit the UE report via NAS message used for logging information delivery to the AMF.

The UE may store the UE slice usage control information related to the usage failed slice. The following exmaples may be applied:

- the UE may store the UE policy information (e.g., UPSC);

- the UE may store the network identity that the UE has received the UE slice usage control information.

The UE may store the UE preference which may be the reason why the slice usage is unavailable. The following examples may be applied:

- the UE may store an Application Id as the UE preference.

- the UE may store an access type as the UE preference.

- the UE may store Access Category as the UE preference.

If the serving network(e.g., the PCF, the AMF) receives the UE report, the serving network may transmit the UE report information to other network elements (e.g., PCF, NSSF) or HPLMN.

If UE report is unavailable or the slice usage is still unavailable after receiving the update slice configuration or URSP configuration, the UE may perform prcedure related to mobility (e.g., PLMN selection, cell (re)selection).

In the present disclosure, the meaning of roaming includes PLMN or SNPN changes. And, PLMN can be interpreted as SNPN.

According to the present disclsoure, the UE may proactively request the network configuration update. For example, the network configuration update may be the update of URSP or network slice configuration for the UE. Based on this request information, the network may configure the network resource for the future usage.

Without this mechanism of the present disclosure, the UE cannot satisfy the dynamic user preferred service by operating based on preconfigured network control information.

Network Slice Unavailability detection may be explained. For example, in step S1106, the UE may detect that the network slice is unavailable, based on the following exmaples.

Based on the URSP, the UE may determine whether to request the establishment of a new PDU session or to use an existing PDU session, which is already established, to transmit data traffic, as exaplined below.

For exmaple the UE may determine whether to establish a new PDU session or use one of the established PDU session(s) based on the URSP rules which include S-NSSAIs, or based on UE local configuration.

For a network slice, time validity cirteria, and/or locaiton validity criteria may be configured. In the present disclsoure, the UE may determine the unavailability of a network slice based on the time validity cirteria, and/or locaiton validity. Time validity critera and location validity criteria related to the network slice may be explained as the following.

For example, the UE may store information related to NSSAI.

If available, the configured NSSAI(s) shall be stored in a non-volatile memory in the Mobile Equipment (ME). For a configured NSSAI, if there is:

a) associated Network Slice Simultaneous Registration Group (NSSRG) information, the NSSRG information may also be stored in a non-volatile memory in the ME;

b) associated NSAG information, the NSAG information may be stored in the ME;

c) associated S-NSSAI time validity information, the S-NSSAI time validity information may also be stored in a non-volatile memory in the ME ;

d) associated S-NSSAI location validity information, the S-NSSAI location validity information may also be stored in a non-volatile memory in the ME; and

e) associated network slice usage control information, the network slice usage control information may also be stored in a non-volatile memory in the ME.

For example, the UE may be configured with network slice validity criteria based on the following exmples based on

For example, the UE may receive S-NSSAI location validity information from the NW. The S-NSSAI location validity information may be based on table 3.

8	7	6	5	4	3	2	1
S-NSSAI location validity information information IEI								octet	1
Length of S-NSSAI location validity information contents								octet 2octet	3
Per-S-NSSAI location validity information for S-NSSAI 1								octet 4 octet a
Per-S-NSSAI location validity information for S-NSSAI 2								octet a+1* octet b*
...								octet b+1* octet c*
Per-S-NSSAI location validity information for S-NSSAI n								octet c+1* octet d*

Table 3 shows an example of S-NSSAI location validity information information element. Location validity information for the network slice may be configured based on table 3. S-NSSAI location validity information information element may include Per-S-NSSAI location validity information for each S-NSSAI.

In table, 3, Per-S-NSSAI location validity information may be based on the following table 4.

8	7	6	5	4	3	2	1
Length of Per-S-NSSAI location validity information for S-NSSAI								octet	4 octet 5
S-NSSAI								octet	6 octet e
NS-AoS								octet e+1 octet a

Table 4 shows an example of per-S-NSSAI location validity information for S-NSSAI. per-S-NSSAI location validity information for S-NSSAI may include S-NSSAI, and NS-AoS. NS-AoS means Network Slice Area of Service.

8	7	6	5	4	3	2	1
Length of Per-S-NSSAI location availability information for S-NSSAI								octet	3
S-NSSAI								octet	4 octet e
Per-S-NSSAI time validity information for the S-NSSAI								octet e+1 octet a

Table 5 shows an example of Per-S-NSSAI time validity information for one S-NSSAI. Table 6 shows information included in " Per-S-NSSAI time validity information for the S-NSSAI" of table 5.

8	7	6	5	4	3	2	1
Length of Per-S-NSSAI time validity information for the S-NSSAI								octet e+1
Time window 1								octet e+2 octet f
Time window
2								octet f+1* octet g*
...								octet g+1* octet h*
Time window m								octet h+1* octet i*

Table 6 shows an example of Per-S-NSSAI time validity information for the S-NSSAI.

The UE may detect an unavailability of the network slice based on the following. For example, the network slice you want to use may not be supported by the serving cell based on location validity information. In this case, the UE may determine the unavailability of that network slice. If the network slice is unavailable, the UE may not perform the PDU session establishment request.

For example, the UE shall not request a PDU session establishment, for the PDU session associated to an S-NSSAI when the UE is not in the NS-AoS of the S-NSSAI.

When the UE detect that the network slice is unavailable or not, the UE may determine whether there is an URSP rule matching to a specific network slice or not. The UE may use the URSP rule based on the following exmaple:

1) The UE may determine that there is a matching URSP rule for a particular network slice. In this case, the UE may send user traffic based on the existing PDU session if it already has a PDU session for that slice. If no PDU session exists for that slice, the UE may perform one of the following operations:

- If the corresponding slice is an Allowed NSSAI, the UE may transmit a PDU session establishment request to the SMF;

- If the slice is not an Allowed NSSAI, the UE may perform the Mobility registration update procedure. The UE may request the network to register for that slice.

2) The UE may determine that there is no matching URSP rule for a particular network slice. In this case, the UE may transmit the DNN or other traffic related parameters to the network. Based on the DNN or other traffic-related parameters, the network may determine for which traffic there is no matching network slice. The network may also update the UE policy including the network slice for this traffic based on the DNN or other traffic related parameters. For example, the UE may have previously received a UE policy including a network slice for eMBB-gaming for VR gaming traffic and that network slice is not available. In this case, the UE may send the related traffic information for the transmission of VR traffic to the network. The UE may then request the network to update the UE policy to include a different network slice (e.g. a network slice for Internet) to be used for VR traffic transport. For example, the other traffic related parameters may include IPv4 remote address type, IPv6 remote address/prefix length type, and/or DNN type. The network may then send the network slice associated with this traffic to the UE. The UE can then know the mapping relationship between the traffic and the network slice.

FIG. 12 illustrates an example of an operation according to an embodiment of the present disclosure.

In addition, the operation of a UE and a network shown in the example of FIG. 12 is only an example. The operation of the UE is not limited by the example of FIG. 12, and the UE and the base station may perform the operations described in various examples of the present specification.

Note that the network in FIG. 11 and FIG. 12 may include an AMF, a SMF, a PCF, a UPF, a base station, a UDM, a DN.

In step S1201, the UE may transmit registration request message to the network(e.g., a first network entity related to mobility management). The registration request message may include capability information.

The capability information may include information that the UE is able to report the unavailability of the network slice

In step S1202, the network(e.g., the first network entity) may transmit registration accept message to the UE.

The network may transmit a time validity information related to the network slice and/or a location validity information related to the network slice to the UE. The network may transmit an on-demand S-NSSAI information to the UE

In step S1203, the UE may transmit information related to unavailability of a preferred network slice to the netwokr (e.g., the first network entity). The preferred metwork slice may be one or more slices included in UP policy received from the network. The UE may transmit information related to unavailability of the network slice, based on that the network slice is detected to be unavailable based on a validity condition for the network slice.

For example, the UE may detect whether the network slice is unavailable or available, based on a time validity information related to the network slice and/or a location validity information related to the network slice. For example, the UE may detect whether the network slice is unavailable or available, based on URSP validation.

In step S1204, the network(e.g., the first network entity or a second network entity related to session management) may transmit information related to a network slice to the UE. The network slice in step S1204 and the network slice in step S1203 may be the same or different. The information related to a network slice may include updated URSP rule or UE configuration for the network slice. The UE may detect the network slice based on URSP validation is available if the on-demand network slice is included in the allowed NSSAI or in the partially allowed NSSAI.

For exmaple, the PCF may transmit the updated URSP rule to the UE. For example, the AMF may transmit UE configuration update to the UE.

For example, in step S1204, the UE may receive new S-NSSAI or updated URSP for the same S-NSSAI, which is detected to be unavailable. In latter case, the netwokr may update the URSP information to prevent the PDU session from being used when the same S-NSSAI is unavailable. For example, the time window is defined in the URSP rule.

The UE may transmit PDU session establishment request message, when the network slice is detected to be available. For example, when the network slice being available after step S1204, the UE may transmit PDU session establishment request message including information related to the network slice to the second network entity (e.g., SMF).

When the network slice is detected to be unavailable, the UE does not transmit the PDU session establishment request message related to the network slice.

According to embodiments of the present disclosure, for on-demand S-NSSAI, its status may change between allowed <-> not-allowed, or the slice validity status may change between met <-> not-met based on the configured time/location validity criteria. In this case, the network cannot immediately update URSP settings, etc. for that S-NSSAI.

For a particular on-demand S-NSSAI, the UE may require PDU session establishment due to user data generation. In this case, if there is no matching UE policy for that S-NSSAI, the UE may send information to the network about the unavailable slice. Alternatively, the UE may transmit a policy failure indication or the currently stored policy information to the network. Based on the information sent by the UE to the network, the network may update the policy information related to that S-NSSAI or reconfigure the UE.

According to embodiments of the present disclosure, the UE may receive slice based UE control information from the NW. The information may be delivered via URSP configuration message or UE configuration message.

For example, the UE may receive slice aware UE mobility information from the NW. The information may be slice aware SoR information or slice aware cell selection information.

For exmaple, the UE may determine preferred slice unavailability. The UE may store the UE control information configured for the unavailable slice. The UE may indicate the preferred slice unavailability to the network. If slice configuration is updated, the UE may request the slice registration to the NW. Or, the UE may perform mobility procedure to change cell, registration area or network.

The present specification may have various effects.

For example, according to the present disclosure, when a UE attempts to use a network slice, if the UE does not have a valid UE policy for the slice, the UE may inform the network about this. According to the present disclosure, the real-time UE policy management overhead and signaling overhead of the network can be reduced.

The effects that may be obtained from the specific examples of this disclosure are not limited to those listed above. For example, there may be a variety of technical effects that a person having ordinary skill in the related art may understand or infer from this disclosure. Accordingly, the specific effects of the present disclosure are not limited to those expressly set forth herein, but may include a variety of effects that may be understood or inferred from the technical features of the present disclosure.

For reference, the operation of the terminal (e.g., UE) described in the present specification may be implemented by the apparatus of FIGS. 1 to 4 described above. For example, the terminal (e.g., UE) may be the first device 100 or the second device 200 of FIG. 2. For example, an operation of a terminal (e.g., UE) described herein may be processed by one or

more processors

102 or 202 . The operation of the terminal described herein may be stored in one or

more memories

104 or 204 in the form of an instruction/program (e.g., instruction, executable code) executable by one or

more processors

102 or 202 . One or

more processors

102 or 202 control one or

more memories

104 or 204 and one or

more transceivers

105 or 206, and may perform the operation of the terminal (e.g., UE) described herein by executing instructions/programs stored in one or

more memories

104 or 204.

In addition, instructions for performing an operation of a terminal (e.g., UE) described in the present disclosure of the present specification may be stored in a non-volatile computer-readable storage medium in which it is recorded. The storage medium may be included in one or

more memories

104 or 204 . And, the instructions recorded in the storage medium may be executed by one or

more processors

102 or 202 to perform the operation of the terminal (e.g., UE) described in the present disclosure of the present specification.

For reference, the operation of a network node (e.g., AMF, SMF, UPF, PCF, UDM, etc.) or base station (e.g., NG-RAN, gNB, eNB, RAN, E-UTRAN etc.) described herein may be implemented by the apparatus of FIGS. 1 to 3 to be described below. For example, a network node or a base station may be the first device 100 of FIG.2 or the second device 200 of FIG.2. For example, the operation of a network node or base station described herein may be processed by one or

more processors

102 or 202. The operation of the terminal described herein may be stored in one or

more memories

more processors

102 or 202. One or

more processors

102 or 202 may perform the operation of a network node or a base station described herein, by controlling one or

more memories

104 or 204 and one or

more transceivers

106 or 206 and executing instructions/programs stored in one or

more memories

104 or 204.

In addition, instructions for performing the operation of the network node or base station described in the present disclosure of the present specification may be stored in a non-volatile (or non-transitory) computer-readable storage medium. The storage medium may be included in one or

more memories

104 or 204. And, the instructions recorded in the storage medium are executed by one or

more processors

102 or 202, so that the operations of a network node or base station are performed.

In the above, preferred embodiments have been exemplarily described, but the present disclosure of the present specification is not limited to such specific embodiments, and thus, modifications, changes, or may be improved.

In the exemplary system described above, the methods are described on the basis of a flowchart as a series of steps or blocks, but are not limited to the order of the steps described, some steps may occur in a different order or concurrent with other steps as described above. In addition, those skilled in the art will understand that the steps shown in the flowchart are not exclusive and that other steps may be included or that one or more steps of the flowchart may be deleted without affecting the scope of rights.

The claims described herein may be combined in various ways. For example, the technical features of the method claims of the present specification may be combined and implemented as an apparatus, and the technical features of the apparatus claims of the present specification may be combined and implemented as a method. In addition, the technical features of the method claim of the present specification and the technical features of the apparatus claim may be combined to be implemented as an apparatus, and the technical features of the method claim of the present specification and the technical features of the apparatus claim may be combined and implemented as a method.

Claims

A method for performing communication, the method performed by a User Equipment (UE) and comprising:

transmitting registration request message including capability information to a first network entity related to mobility management;

receiving registration accept message from the first network entity;

transmitting information related to unavailability of a network slice to the first network entitity, based on that the network slice is detected to be unavailable based on a validity condition for the network slice; and

receiving updated UE route selection policy (URSP)rule or UE configuration for the network slice from the first network entity or a second network entity related to session management.
The method of claim 1,

wherein the capability information includes information that the UE is able to report the unavailability of the network slice.
The method of claim 1 or claim 2, further comprising:

detecting whether the network slice is unavailable or available, based on a time validity information related to the network slice and/or a location validity information related to the network slice.
The method of any one of preceding claims, further comprising:

transmitting Protocol Data Unit (PDU) session establishment request message, when the network slice is detected to be available.
The method of claim 4,

wherein the PDU session establishment request message is not transmitted, when the network slice is detected to be unavailable.
A user equipment (UE) configured to operate in a wireless communication system, the UE comprising:

at least one transceiver;

at least one processor; and

at least one memory that stores instructions and is operably electrically connectable with the at least one processor,

wherein operations performed based on the instructions being executed by the at least one processor include method of claims 1 to 5.
An apparatus performing communication, comprising:

at least one processor; and

at least one memory storing instructions, operatively electrically coupled to the at least one processor, wherein the instructions are executed by the at least one processor to perform operations comprising method of claims 1 to 5.
A non-transitory computer readable storage medium recording instructions,

wherein the instructions, when executed by one or more processors, causing the one or more processors to perform operations compirsing method of claims 1 to 5.
A method for performing communication, the method performed by a first network entity related to mobility management and comprising:

receiving registration request message including capability information to from a User Equipment (UE);

transmitting registration accept message to the UE;

receiving information related to unavailability of a network slice from the UE,

wherein the information related to the unavailability is transmitted by the UE, based on (i) that the network slice is detected to be unavailable based on a validity condition for the network slice or (ii) that the network slice is not detected in the allowed NSSAI or the partially allowed NSSAI; and

transmitting updated URSP rule or UE configuration for the network slice to the UE.
The method of claim 9,

wherein the capability information includes information that the UE is able to report the unavailability of the network slice.
The method of claim 9 or claim 10, further comprising:

transmitting a time validity information related to the network slice and/or a location validity information related to the network slice to the UE.
a first network entity related to mobility management configured to operate in a wireless communication system, the base station comprising:

at least one transceiver;

at least one processor; and

at least one memory that stores instructions and is operably electrically connectable with the at least one processor,

wherein operations performed based on the instructions being executed by the at least one processor include method of claim 9 to claim 11.