Method and apparatus for providing network slice with fine granularity in wireless communication system

Abstract

The present disclosure relates to a 5G or 6G communication system for supporting a higher data transmission rate. The present disclosure provides a method for providing subdivided network slices in a wireless communication system. A method for operating a user equipment (UE) according to an embodiment may include transmitting a registration request message including a request slice (requested NSSAI) and a per cell slice service area support indicator (CSSA support indication) to an access and mobility management function (AMF), and receiving, from the AMF, a registration acceptance message including service area information (a slice area of each allowed NSSAI) for each allowed slice of the UE determined on the basis of the request slice and the per-cell slice service area support indicator.

Description

Technical Field

[0001] The present disclosure provides a method for providing network slices with fine granularity in a wireless communication system. Background Art

[0002] The 5G mobile communication technology defines wide frequency bands to achieve fast transmission speeds and new services, and can be implemented at frequencies below 6 GHz ("sub-6 GHz") such as 3.5 GHz, and in the super high frequency band ("above 6 GHz") such as 28 GHz and 39 GHz, which are called millimeter waves (mmWave). In addition, the 6G mobile communication technology, called the super 5G system, is considered to be implemented in the terahertz band (e.g., 95 GHz to 3 THz) to achieve a transmission speed 50 times faster than the 5G mobile communication technology and an ultra-low latency reduced by 1 / 10.

[0003] In the early stage of the 5G mobile communication technology, beamforming and massive MIMO for reducing propagation path loss and increasing propagation distance in the super high frequency band, supporting various parameter sets for efficient use of super high frequency resources (e.g., operation of multiple subcarrier spacings), dynamic operation of time slot formats, initial access technologies for supporting multi-beam transmission and broadband, definition and operation of bandwidth parts (BWPs), new channel coding such as low density parity check (LDPC) codes for large-scale data transmission and polar codes for highly reliable transmission of control information, L2 preprocessing, and network slicing for providing dedicated networks specified for specific services were standardized in order to meet performance requirements and support services such as enhanced mobile broadband (eMBB), ultra-reliable low latency communication (URLLC), and massive machine type communication (mMTC).

[0004] Currently, considering the services that the 5G mobile communication technology aims to support, improvements and performance enhancements of the initial 5G mobile communication technology are being discussed, and physical layer standardization of technologies such as vehicle-to-everything (V2X) for assisting autonomous vehicles in making driving decisions based on location and status information transmitted from VoNR and increasing user convenience, unlicensed new radio (NR-U) for matching system operations with various regulatory requirements, NR UE energy saving, non-terrestrial network (NTN), which is direct communication between a UE and a satellite to ensure coverage in areas where communication with the terrestrial network is not possible, and positioning technology are being carried out.

[0005] Also standardized are the Industrial Internet of Things (IIoT) technologies for supporting new services through association and integration with other industries, the Integrated Access and Backhaul (IAB) for providing nodes for extending network service areas by supporting access links with radio backhaul links, the mobility enhancements including conditional handover and Dual-Active Protocol Stack (DAPS) handover, the radio interface architecture / protocol of the technology of two-step random access (RACH for NR) for simplifying the random access procedure, and the 5G baseline architecture (e.g., service-based architecture or service-based interface) for combining Network Function Virtualization (NFV) and Software Defined Networking (SDN) technologies and the system architecture / service field of Mobile Edge Computing (MEC) for receiving UE location-based services.

[0006] With the commercialization of 5G mobile communication systems, a soaring number of connected devices will be connected to the communication network, making it expected that the functions and performance of 5G mobile communication systems need to be enhanced and the integrated operation of connected devices is required. For this purpose, new research will be conducted on, for example, Extended Reality (XR) to effectively support, for example, Augmented Reality (AR), Virtual Reality (VR), and Mixed Reality (MR), as well as the enhancement of 5G performance and complexity reduction using Artificial Intelligence (AI) and Machine Learning (ML), support for AI services, support for metaverse services, and drone communication.

[0007] In addition, the development of such 5G mobile communication systems can be the basis for: new waveforms for ensuring the coverage of the terahertz band of 6G mobile communication, multi-antenna transmission technologies such as Full-Dimensional MIMO (FD-MIMO), array antennas, and massive antennas, full-duplex technologies for enhancing the system network and frequency efficiency of 6G mobile communication technologies, and Reconfigurable Intelligent Surfaces (RIS), high-dimensional spatial multiplexing using Orbital Angular Momentum (OAM), metamaterial-based lenses and antennas for enhancing the coverage of terahertz band signals, AI-based communication technologies for realizing system optimization by embedding end-to-end AI support functions and using satellites and artificial intelligence (AI) from the design step, and next-generation distributed computing technologies for realizing services with complexity exceeding the UE operation ability limit through ultra-high-performance communication and computing resources. Summary of the Invention

[0008] Technical Problem

[0009] Network slices can be provided for some or all areas served by network operators. The unit of the area where network slices are provided (i.e., the network slice service area) can be a Tracking Area (TA), which is a unit representing one or more base stations and can be used by network operators to determine the location of UEs.

[0010] When providing network slices on a per-TA basis, it may be difficult to provide network slices for areas finer than a TA (e.g., slices provided only to a specific base station). This disclosure aims to provide network slices in units smaller than a TA (e.g., cells).

[0011] Technical solution

[0012] This disclosure provides a UE-based method and a network-based method for providing network slices on a per-cell basis.

[0013] In the UE-based method for providing network slices on a per-cell basis, the UE can determine whether the UE is located within the slice service area or outside the slice service area based on its own location information and the information received from the network, and operate according to the determined result (e.g., release the session).

[0014] In the network-based method for providing network slices on a per-cell basis, the network can know the location of the UE, determine whether the UE has moved outside the network slice service area, and operate according to the determined result (e.g., release the session).

[0015] A method for operating a user equipment (UE) in a wireless communication system according to an embodiment may include: sending a registration request message including a requested slice (requested NSSAI) and a per-cell slice service area support indicator (CSSA support indication) to an access and mobility management function (AMF), and receiving a registration acceptance message including service area information of each allowed slice of the UE (slice area of each allowed NSSAI) determined based on the requested slice and the per-cell slice service area support indicator from the AMF.

[0016] A method for operating an access and mobility management function (AMF) in a wireless communication system according to an embodiment may include: receiving a registration request message including a requested slice (requested NSSAI) and a per-cell slice service area support indicator (CSSA support indication) from a user equipment (UE), and sending a registration acceptance message including service area information of each allowed slice of the UE (slice area of each allowed NSSAI) determined based on the requested slice and the per-cell slice service area support indicator to the UE.

[0017] A user equipment (UE) in a wireless communication system according to an embodiment includes a transceiver and a controller connected to the transceiver. The controller may control to send a registration request message including a requested slice (requested NSSAI) and a per-cell slice service area support indicator (CSSA support indication) to an access and mobility management function (AMF). The controller may receive a registration acceptance message including service area information for each permitted slice of the UE (slice area for each permitted NSSAI) determined based on the requested slice and the per-cell slice service area support indicator from the AMF.

[0018] An access and mobility management function (AMF) in a wireless communication system according to an embodiment includes a transceiver and a controller connected to the transceiver. The controller may receive a registration request message including a requested slice (requested NSSAI) and a per-cell slice service area support indicator (CSSA support indication) from a user equipment (UE). The controller may control to send a registration acceptance message including service area information for each permitted slice of the UE (slice area for each permitted NSSAI) determined based on the requested slice and the per-cell slice service area support indicator to the UE.

[0019] Through the method for providing network slices on a per-cell basis provided by the present disclosure, a network operator may provide network slice services in a subdivided area.

[0020] Before proceeding with the following detailed description, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: The terms "include" and "comprise," and derivatives thereof, mean including but not limited to; the term "or" is inclusive and means and / or; the phrases "associated with" and "associated therewith," and derivatives thereof, may mean including, being included within, interconnected with, containing, being contained within, connected to or coupled with, coupled to or coupled with, capable of communicating with, cooperating with, interlacing, juxtaposing, adjacent to, bound to or bound with, having, having the property of, etc.; and the term "controller" means any device, system, or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware, software, or some combination of at least two thereof. It should be noted that the functions associated with any particular controller may be centralized or distributed, whether local or remote.

[0021] In addition, the various functions described below can be implemented or supported by one or more computer programs, each formed from computer-readable program code and embodied in a computer-readable medium. The terms "application" and "program" refer to one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, instances, related data, or portions thereof that are adapted to be implemented in appropriate computer-readable program code. The phrase "computer-readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer-readable medium" includes any type of medium that can be accessed by a computer, such as read-only memory (ROM), random access memory (RAM), hard disk drive, compact disc (CD), digital video disc (DVD), or any other type of memory. A "non-transitory" computer-readable medium excludes wired, wireless, optical, or other communication links that transmit transitory electrical signals or other signals. Non-transitory computer-readable media include media in which data can be permanently stored and media in which data can be stored and later rewritten, such as rewritable optical discs or erasable memory devices.

[0022] Certain words and phrases are defined throughout this patent document, and those of ordinary skill in the art should understand that, in many if not most instances, such definitions apply to both the prior and future use of such defined words and phrases.

[0023] Beneficial effects

[0024] The present disclosure provides a UE-based method and a network-based method for providing network slices on a per-cell basis. Brief Description of the Drawings

[0025] When considered in conjunction with the accompanying drawings, a more complete understanding of the present disclosure and many of its attendant aspects will be readily obtained by reference to the following detailed description, as the present disclosure and many of its attendant aspects become better understood, in which:

[0026] Figure 1 Shows a 5G system architecture according to an embodiment of the present disclosure;

[0027] Figure 2 Shows a method for the NSSF to collect slice information of each cell supported by the RAN through the AMF according to an embodiment of the present disclosure;

[0028] Figure 3 Shows a method for providing an allowed area of each cell for each S-NSSAI during the UE registration process according to an embodiment of the present disclosure;

[0029] Figure 4Illustrates a method for providing a slice area of each S-NSSAI through URSP rules during the registration process according to an embodiment of the present disclosure;

[0030] Figure 5 Illustrates a network-based cell-level slice service area support method through the UE configuration update process according to an embodiment;

[0031] Figure 6 Illustrates a UE according to an embodiment of the present disclosure; and

[0032] Figure 7 Illustrates a network device according to an embodiment of the present disclosure. Detailed implementation manners

[0033] The following discussion Figures 1 to 7 and the various embodiments for describing the principles of the present disclosure in this patent document are only illustrative and should not be construed in any way as limiting the scope of the present disclosure. Those skilled in the art will understand that the principles of the present disclosure can be implemented in any appropriately arranged system or device.

[0034] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. When describing the embodiments, descriptions of technologies that are known in the art and not directly related to the present disclosure are omitted. This is to further clarify the gist of the present disclosure without obscuring the gist of the present disclosure.

[0035] For the same reason, some elements may be exaggerated or schematically shown. The size of each element does not necessarily reflect the actual size of the element. In all the drawings, the same reference numerals are used to refer to the same elements.

[0036] Through the embodiments described below in conjunction with the accompanying drawings, the advantages and features of the present disclosure and the methods for implementing them can be understood. However, the present disclosure is not limited to the embodiments disclosed herein and various changes can be made to it. The embodiments disclosed herein are provided only to notify those of ordinary skill in the art of the category of the present disclosure. The present disclosure is only defined by the appended claims. Throughout the specification, the same reference numerals represent the same elements.

[0037] It should be understood that the blocks in each flowchart and combinations of the flowcharts can be executed by computer program instructions.

[0038] In addition, each block may represent a module, segment, or portion of code that includes one or more executable instructions for performing the specified logical function. Furthermore, it should be noted that in some alternative embodiments, the functions mentioned in the blocks may occur in a different order. For example, depending on the corresponding functions, two consecutively shown blocks may be executed substantially simultaneously or in the reverse order.

[0039] As used herein, the term "unit" refers to a software element or a hardware element, such as a Field Programmable Gate Array (FPGA) or an Application Specific Integrated Circuit (ASIC). A unit plays a certain role. However, a "unit" is not limited to software or hardware. A "unit" can be configured in an addressable storage medium or can be configured to execute one or more processors. Thus, by way of example, a "unit" includes elements such as software elements, object-oriented software elements, class elements, and task elements, processes, functions, attributes, procedures, subroutines, program code segments, drivers, firmware, microcode, circuits, data, databases, data architectures, tables, arrays, and variables. The functions provided within components and "units" can be combined into a smaller number of components and "units" or further divided into additional components and "units". In addition, components and "units" can be implemented as one or more CPUs in an execution device or a secure multimedia card. According to an embodiment, a "... unit" can include one or more processors.

[0040] As used herein, for ease of description, terms for identifying access nodes, terms for representing network entities, terms for representing messages, terms for representing interfaces between network entities, and terms for representing various identification information are provided as examples. Thus, the present disclosure is not limited to these terms, and these terms can be replaced with other terms representing objects having equivalent technical meanings.

[0041] Figure 1 A 5G system architecture according to an embodiment of the present disclosure is shown.

[0042] Reference Figure 1 , the 5G mobile communication network includes a 5G user equipment (UE, also referred to as a terminal) 100, a 5G radio access network (RAN, also referred to as a base station) 110, a 5G node B (gNB) 110, an evolved node B (eNB) 110, and a 5G core network 120 to 180.

[0043] The 5G core networks 120 to 180 may include at least one of an Access and Mobility Management Function (AMF) 120 that provides a mobility management function for the UE, a Session Management Function (SMF) 135 that provides a session management function, a User Plane Function (UPF) 130 that performs a data transmission function, a Policy Control Function (PCF) 140 that provides a policy control function, a Unified Data Management (UDM) 145 that provides a data management function (such as subscriber data and policy control data), a Network Slice Selection Function (NSSF) 160 that provides a network slice selection function, a Network Data Analytics Function (NWDAF) 165 that provides a network data analytics function, an Application Function (AF) 170, a Data Network (DN) 175, and a Network Slice Access Control Function (NSACF) 180. The 5G core networks 120 to 180 may also include an NF, such as a Unified Data Repository (UDR), for storing data of various network functions (NFs).

[0044] In the 3GPP system, the conceptual link connecting NFs in the 5G system is defined as a reference point. Examples of reference points included in the 5G system architecture represented in Figure 1 are provided as follows:

[0045] - N1: The reference point between the UE and the AMF;

[0046] - N2: The reference point between the (R)AN and the AMF;

[0047] - N3: The reference point between the (R)AN and the UPF;

[0048] - N4: The reference point between the SMF and the UPF;

[0049] - N5: The reference point between the PCF and the AF;

[0050] - N6: The reference point between the UPF and the DN;

[0051] - N7: The reference point between the SMF and the PCF;

[0052] - N8: The reference point between the UDM and the AMF;

[0053] - N9: The reference point between two core UPFs;

[0054] - N10: The reference point between the UDM and the SMF;

[0055] - N11: The reference point between the AMF and the SMF;

[0056] - N12: The reference point between the AMF and the AUSF;

[0057] -N13: Reference point between the UDM and the Authentication Server Function (AUSF);

[0058] -N14: Reference point between two AMFs; and / or

[0059] -N15: Reference point between the PCF and the AMF in a non-roaming scenario and the reference point between the PCF and the AMF in the visited network in a roaming scenario.

[0060] In a 5G system, network slicing is the technology and architecture for implementing several virtualized and independent logical networks in a physical network. The network operator configures virtual end-to-end networks called network slices and provides services to meet the specified requirements of services / applications. In this case, the network slice is identified by an identifier called the Single Network Slice Selection Assistance Information (S-NSSAI). The network sends a set of allowed slices (e.g., allowed NSSAI) to the UE during the UE registration process, and the UE can send / receive application data through a Protocol Data Unit (PDU) session, and the PDU session is generated by one S-NSSAI (i.e., network slice) in the allowed NSSAI.

[0061] Figure 2 A method is shown in which the NSSF collects slice information of each supported cell from the RAN through the AMF according to an embodiment of the present disclosure. Figure 2 The RAN, AMF, and NSSF shown in can be respectively Figure 1 the RAN 110 of Figure 1 the AMF 120 of Figure 1 the NSSF 160 of.

[0062] In operation 200, the RAN can receive from the AMF and / or Operations, Administration, and Maintenance (OAM) (not shown) whether the AMF supports slicing on a per-cell basis. Whether slicing is supported on a per-cell basis can be included and provided in the NG establishment message or configuration update message sent from the AMF to the RAN.

[0063] In operation 201, the RAN can send an NG establishment request message (or configuration update message) to the AMF, and the NG establishment request message includes at least one of the PLMN id, Tracking Area Code (TAC), and a list of supported slices for each cell. According to an embodiment, the list of supported slices for each cell can be provided only when the AMF supports network slicing on a per-cell basis. According to an embodiment, the list of supported slices for each cell can be configured as a set of the list of supported slices and cell ids. Operation 201 can be performed by multiple RANs connected to the AMF.

[0064] In operation 202, the AMF may send a response message to the RAN for the NG establishment request message (or configuration update message) sent in operation 201.

[0065] In operation 203, the AMF may identify a list of slices of each cell information based on the information received in operation 201, and may send an NssF update request message including the list of slices of each cell information to the NSSF. According to an embodiment, when there are multiple AMFs, the AMF may send the list of slices of each cell information received from the RAN to the NSSF.

[0066] In operation 204, the NSSF may send a response message to the AMF for the NssF update request message sent in operation 203.

[0067] Figure 3 A method for providing a per-cell allowed area for each S-NSSAI in a UE registration process according to an embodiment of the present disclosure is shown. Figure 3 The UE, AMF, NSSF, and UDM shown in Figure 1 may be the UE 100 Figure 1 of Figure 1 the AMF 120 Figure 1 of

[0068] In operation 301, the UE may send a registration request message to the AMF. According to an embodiment, the registration request message may include a requested slice (i.e., a requested NSSAI) and a cell-level slice service area (CSSA) indication (i.e., a per-cell slice service area support indicator).

[0069] According to an embodiment, the allowed slices of the UE and the allowed areas of each allowed slice (i.e., slice service areas) may be provided to the UE by the UDM in the form of subscription information about the UE, or may be provided to the UE by the NSSF. When the UDM provides information about the allowed slices of the UE and the allowed areas of each allowed slice, operations 302 and 303 may be performed, and when the NSSF provides information about the allowed slices of the UE and the allowed areas of each allowed slice, operations 304 and 305 may be performed.

[0070] In operation 302, the UE may send a request message for requesting subscription information about the UE to the UDM. According to an embodiment, the request message may include a UEID (e.g., SUPI) and the CSSA support indication received in operation 301.

[0071] In operation 303, the UDM may send a response message to the AMF that includes subscription information corresponding to the UE ID received in operation 302. According to an embodiment, the response message may include the subscribed S-NSSAI (i.e., identifier information about the network slice to which the UE subscribes). According to an embodiment, when the CSSA support indication is included in the message received by the AMF in operation 301, the response message may include the service area of each subscribed S-NSSAI (the service area of each subscribed slice). According to an embodiment, the service area of each subscribed S-NSSAI may be configured in the form of a list of cell ids (i.e., a list composed of cell identifiers) or a list of TA IDs (a list composed of TA identifiers). According to an embodiment, the service area of each subscribed S-NSSAI may be provided in the form included in the subscribed S-NSSAI, or may be provided separately.

[0072] In operation 304, the AMF may send a request message to the NSSF to request the allowed slices of the UE. According to an embodiment, the request message may include at least one of the requested NSSAI received in operation 301, the CSSA support indication information, and the subscribed S-NSSAI (i.e., the slice information about the UE subscribed obtained from the UDM).

[0073] In operation 305, the NSSF may identify (or calculate) the allowed slices of the UE and the allowed areas (the slice service area of each S-NSSAI) based on the information received in operation 304, and may send a response message including the allowed areas of each S-NSSAI to the AMF.

[0074] In operation 306, the AMF may send a registration acceptance message to the UE, and the registration acceptance message includes the allowed areas of each S-NSSAI determined based on the information received in operation 303 or 305. According to an embodiment, the AMF may calculate a set of allowed slices to be sent to the UE and the service area information of each allowed slice to be sent to the UE (the slice area of each allowed NSSAI) based on the information received in operation 303 or 305 and the current location information of the UE. According to an embodiment, when the same service area information is determined for two or more slices, only one piece of service area information may be provided for the corresponding slices. According to an embodiment, when the service area information is different for each slice, separate service area information may be provided.

[0075] In operation 307, when the UE moves out of the allowed services for any allowed slices received in operation 306 (when the TA or the UE's current cell is not included in the service area of the corresponding slice received in operation 306), the UE may send a request message to the AMF including the allowed slices, the allowed slice area, and the rejected slice information. According to an embodiment, the UE may send a request message to the AMF including the requested NSSAI and the location information about the UE.

[0076] In operation 308, the AMF may send a response message including the slice area for each S-NSSAI to the UE based on the information received from the UE in operation 307.

[0077] Figure 4 A method for providing the slice area for each S-NSSAI through URSP rules during the registration process according to an embodiment of the present disclosure is shown. Figure 4 The situation where each of the V-PCF and the H-PCF operates when the UE roams is shown, but when the UE does not roam, the V-PCF and the H-PCF may operate as one PCF, and the operations between the V-PCF and the H-PCF may be omitted.

[0078] In operation 401, the UE may send a registration request message to the AMF. According to an embodiment, the registration request message may include a requested slice (i.e., the requested NSSAI) and a cell-level slice service area (CSSA) support indication (i.e., per-cell slice service area support indicator).

[0079] In operation 402, the AMF may send a UE policy control creation request (Npcf_UEPolicyControlCreate request) to the V-PCF. According to an embodiment, the message (Npcf_UEPolicyControlCreate request) may include the UE ID (e.g., the subscription permanent identifier (SUPI)) and the CSSA support indication received in operation 401.

[0080] In operation 403, the V-PCF may send a UE policy control message including the information included in the message (Npcf_UEPolicyControlCreate request) received in operation 402 to the H-PCF.

[0081] In operation 404, the H-PCF may send a response message including policy control request (PCR) trigger information to the V-PCF to receive the information necessary to provide URSP rules including the cell-level slice service area.

[0082] In operation 405, the V-PCF may send a response message to the AMF including the information included in the message received in operation 404. According to an embodiment, when a PCR trigger is included in the received message, the AMF may operate according to the conditions satisfied within the PCR trigger (e.g., when the location of the UE changes, notify the V-PCF of the location of the UE).

[0083] In operation 406, the H-PCF may request UE policy-related subscription information from the UDR. According to an embodiment, the request message may include the UE ID. According to an embodiment, when the CSSA support indication is received in operation 403, the H-PCF may include the CSSA support indication in the request message.

[0084] In operation 407, the UDR may include UE policy-related subscription information corresponding to the UE ID of the message received in operation 406 in the response message sent to the H-PCF. According to an embodiment, the UE policy-related subscription information may include the subscribed S-NSSAI and the slice service area for each subscribed S-NSSAI. According to an embodiment, the slice service area for each subscribed S-NSSAI may be provided only when the CSSA support indication is included in the message received in operation 406.

[0085] In operation 408, the H-PCF may generate a URSP rule, include the URSP rule in a UE policy container, and send an Npcf_UEPolicyControlCreate request message to the V-PCF. According to one embodiment, each URSP rule may include at least one of a priority value, a traffic descriptor (TD), a routing descriptor (RSD), and a routing verification criterion.

[0086] According to an embodiment, the UE may search for a URSP rule having a traffic descriptor that matches the application traffic (the URSP rule having the highest priority value when there are multiple URSP rules), and then send the corresponding application traffic through a PDU session corresponding to the RSD included in the corresponding URSP rule. According to an embodiment, when the corresponding URSP rule includes a routing verification criterion and the routing verification criterion includes location information about the UE for which the corresponding URSP rule is allowed, the UE may compare the current location with the allowed UE location information in the routing verification criterion, and when the UE is not currently at the allowed UE location, the UE may not use the corresponding URSP rule.

[0087] According to an embodiment, when the H-PCF receives a CSSA support indication in operation 403, the H-PCF may determine the allowed service area for each S-NSSAI (i.e., the slice service area for each S-NSSAI) according to the operator policy or based on the information received from the UDR in operation 407. According to an embodiment, the H-PCF may generate a URSP rule with cell-level location criteria that reflects the determined slice service area for each S-NSSAI. According to an embodiment, when the URSP rule includes an S-NSSAI in the RSD, the allowed UE location information in the routing verification criteria for the corresponding URSP rule may be determined based on the service area for the corresponding S-NSSAI. According to an embodiment, the allowed UE location information may be configured in the form of a list of cell ids or a list of TA ids, or may be configured as a combination of a list of cell ids and a list of TA ids.

[0088] In operation 409, the V-PCF may send a response message to the H-PCF for the message received in operation 408.

[0089] In operation 410, the V-PCF may send a UE container including the URSP rule with cell-level location criteria received in operation 408 to the UE via the AMF. According to an embodiment, when there is a URSP rule with routing verification criteria including a list of cell ids in the received URSP rule, the UE may determine the URSP rule that includes only the id of the cell where the UE is currently located in the routing verification criteria and use that URSP rule. According to an embodiment, when there is a URSP rule with routing verification criteria including a list of TA ids in the received URSP rule, the UE may determine that the URSP rule that includes only the id of the TA where the UE is currently located in the routing verification criteria is valid and use that URSP rule.

[0090] In operation 411, the remaining registration process may be performed.

[0091] Figure 5 A network-based cell-level slice service area support method through a UE configuration update process according to an embodiment of the present disclosure is shown.

[0092] In operation 501, the UE may send a registration request message (AN message) to the RAN.

[0093] In operation 502, the RAN may transfer the registration request message received in operation 501 to the AMF (N2 message).

[0094] In operation 503, when there is a slice corresponding to the cell-level slice service area in the requested slice included in the message requested by the UE in operation 501, the AMF may send a request message (location subscription request) for requesting the RAN to provide a notification regarding the location change of the UE. According to an embodiment, the request message may include at least one of allowed slice information, per-slice service area information (a list of cell id types), and UE id.

[0095] In operation 504, the RAN may send a response message (location subscription response) to the AMF.

[0096] In operation 505, the remaining UE registration process may be performed.

[0097] In operation 506, the RAN may identify whether the current location of the UE is included in the service area of each slice for all the slices received in operation 503. According to an embodiment, when there is a service area that does not include the current UE location, the RAN may include information indicating the S-NSSAI and that the UE is outside the service area in the message sent to the AMF.

[0098] When the message received in operation 503 includes information for periodically requesting notification of the location of the UE (e.g., cell id), the RAN may periodically provide location information about the UE to the AMF.

[0099] In operation 507, when the message received in operation 506 includes information indicating that the UE is outside the service area, or when there is a slice with a service area that does not correspond to the location of the UE included in the message received in operation 506, the AMF may exclude the corresponding slice from the slices allowed for the UE (allowed NSSAI). The excluded slice may be included in the rejected NSSAI. In operation 507, if necessary, the AMF may update the slices allowed for the UE (allowed NSSAI) based on the new location information about the UE.

[0100] In operation 508, the AMF may include the allowed NSSAI determined in operation 507 in the UE configuration update command message in the message N2 sent to the RAN.

[0101] In operation 509, the RAN may deliver the message received in operation 508 to the UE.

[0102] According to an embodiment, when the UE configuration update command message includes the allocated NSSAI, the UE may delete the existing allocated NSSAI and store the received allocated NSSAI. According to an embodiment, when there is a PDU session for a slice that does not correspond to the slice included in the received allowed NSSAI, the UE may internally delete (locally release) all information regarding the corresponding PDU session or send a NAS message for releasing the corresponding PDU session to the AMF.

[0103] Figure 6 A UE according to an embodiment of the present disclosure is shown.

[0104] As Figure 6 shown, the UE of the present disclosure may include a transceiver 610, a memory 620, and a processor 630. The processor 630, transceiver 610, and memory 620 of the UE may operate according to the above communication method of the UE. However, the components of the UE are not limited thereto. For example, the UE may include more or fewer components than the above components. The processor 630, transceiver 610, and memory 620 may be implemented in the form of a single chip.

[0105] The transceiver 610 collectively refers to the transmitter of the UE and the receiver of the UE, and may send and receive signals to / from a base station or a network entity. The signals transmitted / received with the base station may include control information and data. To this end, the transceiver 610 may include a radio frequency (RF) transmitter for upconverting and amplifying the transmitted signal and an RF receiver for low-noise amplifying the received signal and downconverting the frequency of the received signal. However, this is merely an example of the transceiver 610, and the components of the transceiver 610 are not limited to the RF transmitter and the RF receiver.

[0106] In addition, the transceiver 610 may include a wired / wireless transceiver and may include various components for transmitting / receiving signals.

[0107] The transceiver 610 may receive signals via a radio channel, output the signals to the processor 630, and transmit the signals output from the processor 630 via the radio channel.

[0108] In addition, the transceiver 610 may receive communication signals and output the communication signals to the processor, and transmit the signals output from the processor to the network entity through a wired / wireless network.

[0109] The memory 620 may store programs and data necessary for the operation of the UE. The memory 620 may store control information or data included in the signals obtained by the UE. The memory 620 may include storage media such as ROM, RAM, hard disk, CD-ROM, and DVD, or a combination of storage media.

[0110] The processor 630 may control a series of processes by which the UE can operate according to the above embodiments. The processor 630 may include at least one processor. For example, the processor 630 may include a communication processor (CP) that executes control for communication and an application processor (AP) that controls the upper layer, such as application programs.

[0111] Figure 7 A network device according to an embodiment of the present disclosure is shown. Figure 7 The shown network device may be Figures 2 to 5 any one of the shown RAN (or base station), AMF, NSSF, UDM, PCF, V-PCF, H-PCF, UDR.

[0112] As Figure 7 shown, the network device of the present disclosure may include a transceiver 710, a memory 720, and a processor 730. The processor 730, transceiver 710, and memory 720 of the network device may be operated according to the above network device communication method. However, the components of the network entity are not limited thereto. For example, the network entity may include more or fewer components than the above components. The processor 730, transceiver 710, and memory 720 may be implemented in the form of a single chip.

[0113] The transceiver 710 collectively refers to the receiver of the network entity and the transmitter of the network entity, and may send and receive signals to / from the UE or another network entity. In this case, the signals transmitted / received with the base station may include control information and data. To this end, the transceiver 710 may include a radio frequency (RF) transmitter for up-converting and amplifying the transmitted signal and an RF receiver for low-noise amplifying the received signal and down-converting the frequency of the received signal. However, this is merely an example of the transceiver 710, and the components of the transceiver 710 are not limited to the RF transmitter and the RF receiver. The transceiver 710 may include a wired / wireless transceiver and may include various components for transmitting / receiving signals.

[0114] In addition, the transceiver 710 may receive a signal via a communication channel (e.g., a radio channel), output the signal to the processor 730, and transmit the signal output from the processor 730 via the radio channel.

[0115] In addition, the transceiver 710 may receive a communication signal and output the communication signal to the processor, and transmit the signal output from the processor to the UE or the network device via a wired / wireless network.

[0116] The memory 720 can store programs and data required for the operation of the network device. In addition, the memory 720 can store control information or data included in the signals obtained by the network device. The memory 720 can include storage media such as ROM, RAM, hard disks, CD-ROMs, and DVDs, or a combination of storage media.

[0117] The processor 730 can control a series of processes by which the network entity can operate according to the above embodiments. The processor 730 can include at least one processor. The methods according to the embodiments described in the specification or claims of the present disclosure can be implemented in hardware, software, or a combination of hardware and software.

[0118] When implemented in software, a computer-readable storage medium storing one or more programs (software modules) can be provided. The one or more programs stored in the computer-readable storage medium are configured to be executed by one or more processors in the electronic device. The one or more programs include instructions that enable the electronic device to execute the methods according to the embodiments described in the specification or claims of the present disclosure.

[0119] Although specific embodiments of the present disclosure have been described above, various changes can be made thereto without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the above embodiments, but should be defined by the appended claims and their equivalents.

[0120] Although the present disclosure has been described with various embodiments, various changes and modifications can be suggested to those skilled in the art. The present disclosure is intended to cover such changes and modifications that fall within the scope of the appended claims.

Claims

1. A method performed by a user equipment (UE) in a wireless communication system, the method comprising: sending a registration request message including a requested slice and a per-cell slice service area (CSSA) support indicator to an access and mobility management function (AMF); and receiving from the AMF a registration acceptance message including service area information for each permitted slice for the UE based on the requested slice and the per-cell slice service area support indicator, wherein the requested slice includes requested network slice selection assistance information (NSSAI), and the service area information for each permitted slice includes a slice area for each permitted NSSAI.

2. The method according to claim 1, wherein the service area information for each permitted slice includes at least one of identifier information for at least one cell and identifier information for at least one tracking area (TA).

3. The method according to claim 1, further comprising: when the UE moves outside the service area of a permitted slice, sending a request message to the AMF for requesting a permitted slice and a permitted slice area.

4. The method according to claim 3, further comprising: receiving from the AMF a response message including information on the permitted slice area and the permitted slice requested in the request message.

5. A method performed by an access and mobility management function (AMF) in a wireless communication system, the method comprising: receiving from a user equipment (UE) a registration request message including a requested slice and a per-cell slice service area (CSSA) support indicator; and sending to the UE a registration acceptance message including service area information for each permitted slice for the UE based on the requested slice and the per-cell slice service area support indicator, wherein the requested slice includes requested network slice selection assistance information (NSSAI), and the service area information for each permitted slice includes a slice area for each permitted NSSAI.

6. The method according to claim 5, wherein the service area information for each permitted slice includes at least one of identifier information for at least one cell and identifier information for at least one tracking area (TA).

7. The method according to claim 5, further comprising: when the UE moves outside the service area of a permitted slice, receiving from the UE a request message for requesting a permitted slice and a permitted slice area.

8. The method according to claim 7, further comprising: sending to the UE a response message including information on the permitted slice area and the permitted slice requested in the request message.

9. A user equipment (UE) in a wireless communication system, the UE comprising: a transceiver; and a controller coupled to the transceiver, and the controller is configured to control the transceiver to: send a registration request message including a requested slice and a per-cell slice service area (CSSA) support indicator to an access and mobility management function (AMF), and receive from the AMF a registration acceptance message including service area information for each permitted slice for the UE based on the requested slice and the per-cell slice service area support indicator, Wherein, the requested slice includes the requested Network Slice Selection Assistance Information (NSSAI), and the serving area information of each permitted slice includes the slice area of each permitted NSSAI.

10. The UE according to claim 9, wherein, the serving area information of each permitted slice includes at least one of identifier information for at least one cell and identifier information regarding at least one Tracking Area (TA).

11. The UE according to claim 9, wherein, the controller is further configured to send a request message for requesting the permitted slice and the permitted slice area to the AMF when the UE moves outside the serving area of the permitted slice.

12. The UE according to claim 11, wherein, the controller is further configured to receive a response message from the AMF, the response message including the information of the permitted slice area and the permitted slice requested in the request message.

13. An Access and Mobility Management Function (AMF) in a wireless communication system, the AMF comprising: a transceiver; and a controller coupled to the transceiver, and the controller is configured to control the transceiver to: receive a registration request message from a User Equipment (UE), the registration request message including a requested slice and a per-cell slice serving area (CSSA) support indicator, and send a registration acceptance message to the UE, the registration acceptance message including the serving area information of each permitted slice for the UE based on the requested slice and the per-cell slice serving area support indicator, wherein, the requested slice includes the requested Network Slice Selection Assistance Information (NSSAI), and the serving area information of each permitted slice includes the slice area of each permitted NSSAI.

14. The AMF according to claim 13, wherein, the serving area information of each permitted slice includes at least one of identifier information for at least one cell and identifier information regarding at least one Tracking Area (TA).

15. The AMF according to claim 13, wherein, the controller is further configured to receive a request message for requesting the permitted slice and the permitted slice area from the UE when the UE moves outside the serving area of the permitted slice.

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