Communication device method

Abstract

An exemplary objective of the present disclosure is to provide a method and apparatus that can solve the problem that current 3GPP specifications lack a mechanism for addressing a new attribute, "maximum number of UEs with at least one PDU session / PDN connection." An aspect of the present disclosure includes a method of a communications device. The method includes receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI). The method includes determining whether the S-NSSAI includes an attribute related to the maximum number of User Equipments (UEs) that simultaneously use the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. If the method determines that the S-NSSAI includes the attribute, it includes continuing to send a second message. The second message includes the S-NSSAI for performing a procedure for checking and updating the number of UEs available per network slice.

Description

[Technical Field]

[0001] The present disclosure relates to a method of a communication device, a method of a User Equipment (UE), a communication device, and a UE. [Background technology]

[0002] The GSMA has sent Liaison Statement (LS) S2-2202800 (Non-Patent Document 9) to request SA2 to specify support for a new Network Slice Type (NEST) attribute, "Maximum number of UEs with at least one PDU session / PDN connection", defined in the GSMA document, Generic Network Slice Template (Non-Patent Document 10).

[0003] The Service and System Aspects Working Group 2 (SA2) of the 3rd Generation Partnership Project (3GPP®) is working on enhancing the capabilities and functions of the 5GS architecture. 3GPP contribution SP-220988 (Non-Patent Document 11) is a Work Item Description (WID) for the SA2 Technical Enhancement or Improvement (TEI) agreed for Release 18, and its purpose is to specify a request from the GSMA to address the 5GS enhancements for adding a new NEST attribute: "Maximum number of UEs with at least one PDU session / PDN connection." [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP TR 21.905: Vocabulary for 3GPP Specifications.V17.1.0(2021-12) [Non-patent document 2] 3GPP TS23.501:System architecture for the 5G System(5GS).V17.6.0(2022-09) [Non-licensed document 3] 3GPP TS23.502:Procedures for the 5G System(5GS).V17.6.0(2022-09)

Non-licensed Document 4

Non-licensed Document 5

Non-licensed Document 6

Non-licensed Document 7

Non-licensed literature 9

Non-licensed literature 10

[0005] Current 3GPP specifications (e.g., TS23.501 (Non-Patent Document 2) and TS23.502 (Non-Patent Document 3)) do not support the new NEST attribute "maximum number of UEs with at least one PDU session / PDN connection" defined by GSMA (Non-Patent Document 10). For 5GS network slice(s) supporting EPS interconnection, 5GS counts UEs registered with 5GS, while EPS counts UEs with at least one PDN connection, which may result in a constraint that the counting is not unified. Therefore, a requirement is required to address the constraint for unified counting by considering the new attribute "maximum number of UEs with at least one PDU session / PDN connection." Therefore, for example, it is necessary to address the constraint for unified counting by considering the new attribute "maximum number of UEs with at least one PDU session / PDN connection" of 5GS network slice(s) that can be used by the maximum number of UEs simultaneously (for both 5GS and EPS UEs). However, the current 3GPP specifications do not provide a mechanism for addressing at least one of the new attributes and requirements. [Means for solving the problem]

[0006] In a first exemplary aspect, a method for a communication device includes: receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); Determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; If it is determined that the S-NSSAI has the attribute, continue to send a second message, wherein the second message includes an S-NSSAI for performing a confirmation and update procedure for the number of UEs available per network slice.

[0007] In a second exemplary aspect, a method of a communication device includes: receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); Determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; If it is determined that the S-NSSAI has the attribute, sending a second message, the second message including an S-NSSAI for performing a confirmation and update procedure for the number of UEs available per network slice.

[0008] In a third exemplary aspect, a method of User Equipment (UE) comprises: transmitting a first message including Single Network Slice Selection Assistance Information (S-NSSAI); If the S-NSSAI has an attribute related to the maximum number of UEs using the network slice simultaneously with at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection, the procedure for confirming and updating the number of UEs available per network slice has not been performed, and receiving a second message having a list including at least one S-NSSAI, the S-NSSAI being included in the list.

[0009] In a fourth exemplary aspect, a method for a communication device includes: receiving a first message from an Access and Mobility Management Function (AMF), the first message including Single Network Slice Selection Assistance Information (S-NSSAI); Determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; If it is determined that the S-NSSAI has the attribute, continuing to perform the procedure of checking and updating the number of UEs available per network slice for the S-NSSAI.

[0010] In a fifth exemplary aspect, a method of a communications device includes communicating with another communications device and transmitting information to the other communications device indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has attributes related to a maximum number of user equipments simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection.

[0011] In a sixth exemplary aspect, a method of a communication device includes: communicating with other communication devices; The method includes receiving information from another communication device indicating that the Single Network Slice Selection Assistance Information (S-NSSAI) has attributes regarding the maximum number of user equipments that will simultaneously use the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection.

[0012] In a seventh exemplary aspect, a communication device includes: means for receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); A means for determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; means for continuing to send the second message if it determines that the S-NSSAI has the attribute; The second message includes an S-NSSAI for performing a procedure to check and update the number of UEs available per network slice.

[0013] In an eighth exemplary aspect, a communication device includes: means for receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); A means for determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; means for transmitting a second message if the S-NSSAI determines that the S-NSSAI has the attribute; The second message includes an S-NSSAI for performing a procedure to check and update the number of UEs available per network slice.

[0014] In a ninth exemplary aspect, a User Equipment (UE) includes means for receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); and means for receiving a second message including a list including at least one S-NSSAI for which a procedure for checking and updating the number of available UEs per network slice has not been performed, if the S-NSSAI includes an attribute related to a maximum number of UEs simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; The S-NSSAI is included in the list.

[0015] In a tenth exemplary aspect, a communication device includes: means for receiving a first message from an Access and Mobility Management Function (AMF), the first message including Single Network Slice Selection Assistance Information (S-NSSAI); A means for determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; and means for continuing to perform a procedure for checking and updating the number of UEs available per network slice for the S-NSSAI if it is determined that the S-NSSAI has the attribute.

[0016] In an eleventh exemplary aspect, a communication device includes: means for communicating with other communication devices; The method includes means for transmitting information to another communication device, instructing that the Single Network Slice Selection Assistance Information (S-NSSAI) has attributes related to the maximum number of user equipments that will simultaneously use the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection.

[0017] In a twelfth exemplary aspect, a communication device comprises: means for communicating with other communication devices; The method includes receiving information from another communication device, the information indicating that the Single Network Slice Selection Assistance Information (S-NSSAI) has attributes regarding the maximum number of user equipments that will simultaneously use the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. [Effects of the Invention]

[0018] The present disclosure provides a method or the like that addresses at least one of the new attributes and requirements in the current 3GPP specifications. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a signaling diagram of a first example according to the first aspect. [Figure 2] FIG. 2 is a signaling diagram of a second example embodiment of the first aspect. [Figure 3] FIG. 3 is a signaling diagram of a first example of the second aspect. [Figure 4] FIG. 4 is a signaling diagram of a second example according to the second aspect. [Figure 5] FIG. 5 is a signaling diagram of a first example of the third aspect. [Figure 6] FIG. 6 is a signaling diagram of a second example of the third aspect. [Figure 7] FIG. 7 is a signaling diagram of a first example of the fourth aspect. [Figure 8] FIG. 8 is a diagram showing an outline of the system. [Figure 9] FIG. 9 is a block diagram illustrating a UE. [Figure 10] FIG. 10 is a block diagram illustrating an (R)AN node. [Figure 11] FIG. 11 is a diagram illustrating a system overview of an (R)AN node based on the O-RAN architecture. [Figure 12] FIG. 12 is a block diagram illustrating an RU. [Figure 13] FIG. 13 is a block diagram showing a DU. [Figure 14] FIG. 14 is a block diagram showing a CU. [Figure 15] FIG. 15 is a block diagram showing AMF. [Figure 16] FIG. 16 is a block diagram showing an SMF. [Figure 17] FIG. 17 is a block diagram illustrating the UPF. [Figure 18] FIG. 18 is a block diagram showing a PCF. [Figure 19] FIG. 19 is a block diagram illustrating the NEF. [Figure 20] FIG. 20 is a block diagram illustrating the UDM. [Figure 21] FIG. 21 is a block diagram illustrating the NSSF. [Figure 22] FIG. 22 is a block diagram illustrating the NSACF. DETAILED DESCRIPTION OF THE INVENTION

[0020] (abbreviation) This document uses TR21.905 (Non-Patent Document 1) and the following abbreviations. If the same abbreviations exist in TR21.905 (Non-Patent Document 1), the abbreviations defined in this document take precedence over those definitions. 4G-GUTI 4G Globally Unique Temporary UE Identity 5GC 5G Core Network 5GLAN 5G Local Area Network 5GS 5G System 5G-AN 5G Access Network 5G-AN PDB 5G Access Network Packet Delay Budget 5G-EIR 5G-Equipment Identity Register 5G-GUTI 5G Globally Unique Temporary Identifier 5G-BRG 5G Broadband Residential Gateway 5G-CRG 5G Cable Residential Gateway 5G GM 5G Grand Master 5G-RG 5G Residential Gateway 5G-S-TMSI 5G S-Temporary Mobile Subscription Identifier 5G VN 5G Virtual Network 5QI 5G QoS Identifier ABBA Anti-Bidding-down Between Architectures AF Application Function AMF Access and Mobility Management Function API Application Programming Interface AS Access Stratum ATSSS Access Traffic Steering,Switching,Splitting ATSSS-LL ATSSS Low-Layer AUSF Authentication Server Function AUTN Authentication token BBF Broadband Forum BMCA Best Master Clock Algorithm BSF Binding Support Function CAG Closed Access Group CAPIF Common API Framework for 3GPP northbound APIs CHF Charging Function CN PDB Core Network Packet Delay Budget CP Control Plane CU Centralized Unit DAPS Dual Active Protocol Stacks DL Downlink DN Data Network DNAI DN Access Identifier DNN Data Network Name DRX Discontinuous Reception DS-TT Device-side TSN translator DU Distributed Unit ePDG evolved Packet Data Gateway EAP Extensible Authentication Protocol EBI EPS Bearer Identity EPS Evolved Packet System EUI Extended Unique Identifier FAR Forwarding Action Rule FN-BRG Fixed Network Broadband RG FN-CRG Fixed Network Cable RG FN-RG Fixed Network RG FQDN Fully Qualified Domain Name GFBR Guaranteed Flow Bit Rate GMLC Gateway Mobile Location Centre GPSI Generic Public Subscription Identifier GUAMI Globally Unique AMF Identifier GUTI Globally Unique Temporary UE Identity HR Home Routed(roaming) IAB Integrated access and backhaul IMEI International Mobile Equipment Identity IMEI / TAC IMEI Type Allocation Code IMS IP Multimedia Subsystem IOWN Innovative Optical and Wireless Network IPUPS Inter PLMN UP Security I-SMF Intermediate SMF I-UPF Intermediate UPF LADN Local Area Data Network LBO Local Break Out(roaming) LMF Location Management Function LoA Level of Automation LPP LTE Positioning Protocol LRF Location Retrieval Function LTE Long Term Evolution MAC Medium Access Control MCC Mobile country code MCX Mission Critical Service MDBV Maximum Data Burst Volume MFBR Maximum Flow Bit Rate MICO Mobile Initiated Connection Only MNC Mobile Network Code MO Mobile Originated MPS Multimedia Priority Service MPTCP Multi-Path TCP Protocol MT Mobile Terminated MT Mobile Termination N3IWF Non-3GPP InterWorking Function N5CW Non-5G-Capable over WLAN NAI Network Access Identifier NAS Non-Access Stratum NEF Network Exposure Function NEST Network Slice Type NF Network Function NGAP Next Generation Application Protocol ngKSI Next Generation Key Set Identifier NID Network identifier NPN Non-Public Network NR New Radio NRF Network Repository Function NSAC Network Slice Admission Control NSACF Network Slice Admission Control Function NSI ID Network Slice Instance Identifier NSSAA Network Slice-Specific Authentication and Authorization NSSAAF Network Slice-Specific Authentication and Authorization Function NSSAI Network Slice Selection Assistance Information NSSF Network Slice Selection Function NSSP Network Slice Selection Policy NW-TT Network-side TSN translator NWDAF Network Data Analytics Function O-RAN Open RAN Alliance O-DU O-RAN Distributed Unit O-CU O-RAN Centralized Unit O-RU O-RAN Radio Unit PCF Policy Control Function PDB Packet Delay Budget PDCP Packet Data Convergence Protocol PDR Packet Detection Rule PDU Protocol Data Unit PEI Permanent Equipment Identifier PER Packet Error Rate PFD Packet Flow Description PLMN Public Land Mobile Network PNI-NPN Public Network Integrated Non-Public Network PPD Paging Policy Differentiation PPF Paging Proceed Flag PPI Paging Policy Indicator PSA PDU Session Anchor PTP Precision Time Protocol QFI QoS Flow Identifier QoE Quality of Experience QoS Quality of Service RACS Radio Capabilities Signalling optimisation (R)AN(Radio)Access Network RG Residential Gateway RU Radio Unit RIM Remote Interference Management RLC Radio Link Control RQA Reflective QoS Attribute RQI Reflective QoS Indication RRC Radio Resource Control RSN Redundancy Sequence Number SA NR Standalone New Radio SBA Service Based Architecture SBI Service Based Interface SCP Service Communication Proxy SD Slice Differentiator SDAP Service Data Adaptation Protocol SEAF Security Anchor Functionality SEPP Security Edge Protection Proxy SMF Session Management Function SMS Short Message Service SMSF Short Message Service Function SN Sequence Number SN name Serving Network Name SNPN Stand-alone Non-Public Network S-NSSAI Single Network Slice Selection Assistance Information SOR Steering Of Roaming SSC Session and Service Continuity SSCMSP Session and Service Continuity Mode Selection Policy SST Slice / Service Type SUCI Subscription Concealed Identifier SUPI Subscription Permanent Identifier SV Software Version TAI Tracking Area Identity TCP Transmission Control Protocol TNAN Trusted Non-3GPP Access Network TNAP Trusted Non-3GPP Access Point TNGF Trusted Non-3GPP Gateway Function TNL Transport Network Layer TNLA Transport Network Layer Association TSC Time Sensitive Communication TSCAI TSC Assistance Information TSN Time Sensitive Networking TSN GM TSN Grand Master TSP Traffic Steering Policy TT TSN Translator TWIF Trusted WLAN Interworking Function UCMF UE radio Capability Management Function UDM Unified Data Management UDR Unified Data Repository UDSF Unstructured Data Storage Function UE User Equipment UL Uplink UL CL Uplink Classifier UP User Plane UPF User Plane Function URLLC Ultra Reliable Low Latency Communication URRP-AMF UE Reachability Request Parameter for AMF URSP UE Route Selection Policy UU Interface between User Equipment and Radio Access Network VID VLAN Identifier VLAN Virtual Local Area Network W-5GAN Wireline 5G Access Network W-5GBAN Wireline BBF Access Network W-5GCAN Wireline 5G Cable Access Network W-AGF Wireline Access Gateway Function WLAN Wireless Local Area Network WUS Wake Up Signal

[0021] (definition) This document applies to 3GPP TR21.905 (Non-Patent Document 1) and the following terms and definitions. If the same term is defined in 3GPP TR21.905 (Non-Patent Document 1), the term defined in this document takes precedence.

[0022] (General rules) Those skilled in the art will understand that elements in the figures are illustrated for simplicity and may not necessarily be drawn to scale. Further, with respect to the configuration of a device, one or more components of the device may be represented in the figures by conventional symbols, and the figures may show only certain details relevant to an understanding of aspects of the present disclosure so as not to obscure the figures with details that will be readily apparent to one of ordinary skill in the art having the benefit of the description herein.

[0023] For the purposes of promoting an understanding of the principles of the present disclosure, reference will be made to the embodiments illustrated in the figures and specific language will be used to describe them. However, it will be understood that no limitation of the scope of the present disclosure is intended thereby. Such changes and further modifications in the illustrated systems, and such further applications of the principles of the present disclosure as would normally occur to one skilled in the art, should be construed as being within the scope of the present disclosure. The terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process or method comprising a list of steps does not include only those steps, but may also include other steps not expressly listed or inherent in such process or method. Similarly, "comprises...a" following one or more devices, entities, subsystems, elements, structures, or components does not, without further constraints, exclude the presence of other devices, subsystems, elements, structures, components, additional devices, additional subsystems, additional elements, additional structures, or additional components. Throughout this specification, appearances of the phrases "in one embodiment," "in another embodiment," and similar language may, but do not necessarily, all refer to the same embodiment.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The systems, methods, and examples provided herein are illustrative only and are not intended to be limiting.

[0025] In the following specification and claims, reference will be made to a number of terms that shall be defined to have the following meanings: The singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

[0026] As used herein, information is associated with data and knowledge because data is meaningful information and values ​​attributed to parameters. Further knowledge refers to understanding abstract or concrete concepts. It should be noted that this exemplary system is simplified to facilitate explanation of the disclosed subject matter and is not intended to limit the scope of the present disclosure. Other devices, systems, and configurations can be used in addition to or instead of the system to implement aspects disclosed herein, and all such aspects are considered to be within the scope of the present disclosure.

[0027] Furthermore, each of the aspects and elements included in each aspect described below may be implemented independently or in combination with one another. These aspects include novel features that are different from one another. Therefore, these aspects contribute to achieving different objectives or solving different problems, and to obtaining different advantages from one another.

[0028] In the present disclosure, the phrase "A and / or B" may mean "at least one of A and B."

[0029] Signaling(s) or message(s) between communication devices (e.g., UE(s), AMF(s), SMF(s), NSACF(s), etc.) can be realized using existing message(s) between the communication devices or newly defined message(s).

[0030] An exemplary object of the present disclosure is to provide a method and apparatus that can solve the above problems.

[0031] A method for a communications device according to an exemplary aspect of the present disclosure includes receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI). The method includes determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. If the method determines that the S-NSSAI has the attribute, it includes continuing to transmit a second message including the S-NSSAI for performing a procedure for checking and updating the number of UEs available per network slice.

[0032] A method for a communications device according to an exemplary aspect of the present disclosure includes receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI). The method includes determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. If the method determines that the S-NSSAI has the attribute, it includes transmitting a second message including the S-NSSAI for performing a procedure for checking and updating the number of UEs available per network slice.

[0033] A method for a user equipment (UE) according to an example aspect of the present disclosure includes transmitting a first message including Single Network Slice Selection Assistance Information (S-NSSAI). If the S-NSSAI includes an attribute related to a maximum number of UEs simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection, the method includes receiving a second message including a list including at least one S-NSSAI for which a procedure for checking and updating the number of UEs available per network slice has not been performed. The S-NSSAI is included in the list.

[0034] A method for a communications device according to an example aspect of the present disclosure includes receiving a first message from an Access and Mobility Management Function (AMF), the first message including Single Network Slice Selection Assistance Information (S-NSSAI). The method includes determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) that simultaneously use the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. If the method determines that the S-NSSAI has the attribute, continuing to perform a verification and update procedure of the number of UEs available per network slice.

[0035] A method for a communications device according to an exemplary aspect of the present disclosure includes communicating with another communications device, the method including transmitting, to the other communications device, information indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has attributes related to a maximum number of user equipments simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection.

[0036] A method of a communications device according to an example aspect of the present disclosure includes communicating with another communications device, the method including receiving information from the other communications device, the information indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has attributes related to a maximum number of user equipments simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection.

[0037] A communications device according to an exemplary aspect of the present disclosure includes a memory and at least one hardware processor coupled to the memory. The at least one hardware processor is configured to receive a first message including Single Network Slice Selection Assistance Information (S-NSSAI). The at least one hardware processor is configured to determine whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. The at least one hardware processor is configured to continue transmitting a second message if it determines that the S-NSSAI has the attribute. The second message includes the S-NSSAI for performing a procedure for checking and updating the number of UEs available per network slice.

[0038] A communications apparatus according to an exemplary aspect of the present disclosure includes a memory and at least one hardware processor coupled to the memory. The at least one hardware processor is configured to receive a first message including Single Network Slice Selection Assistance Information (S-NSSAI). The at least one hardware processor is configured to determine whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. If the at least one hardware processor determines that the S-NSSAI has the attribute, the at least one hardware processor is configured to transmit a second message including the S-NSSAI for performing a procedure for checking and updating the number of UEs available per network slice.

[0039] A user equipment (UE) according to an exemplary aspect of the present disclosure includes a memory and at least one hardware processor coupled to the memory. The at least one hardware processor is configured to transmit a first message including Single Network Slice Selection Assistance Information (S-NSSAI). If the S-NSSAI includes an attribute related to a maximum number of UEs simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection, the at least one hardware processor is configured to receive a second message including a list including at least one S-NSSAI for which a procedure for checking and updating the number of available UEs per network slice has not been performed. The S-NSSAI is included in the list.

[0040] A communications apparatus according to an exemplary aspect of the present disclosure includes a memory and at least one hardware processor coupled to the memory. The at least one hardware processor is configured to receive a first message including Single Network Slice Selection Assistance Information (S-NSSAI) from an Access and Mobility Management Function (AMF). The at least one hardware processor is configured to determine whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. The at least one hardware processor is configured to continue performing a verification and update procedure of the number of UEs available per network slice if it determines that the S-NSSAI has the attribute.

[0041] A communications device according to an exemplary aspect of the present disclosure includes a memory and at least one hardware processor coupled to the memory, the at least one hardware processor configured to communicate with another communications device, and the at least one hardware processor configured to transmit, to the other communications device, information indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has attributes related to a maximum number of user equipments simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection.

[0042] A communications device according to an exemplary aspect of the present disclosure includes a memory and at least one hardware processor coupled to the memory. The at least one hardware processor is configured to communicate with another communications device. The at least one hardware processor is configured to receive, from the other communications device, information indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has attributes related to a maximum number of user equipments simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection.

[0043] (First aspect) This aspect provides a mechanism to accommodate the new GSMA-defined attribute "maximum number of UEs with at least one PDU session / PDN connection" per network slice by configuring the AMF and SMF with attribute details for monitoring and limiting the total number of UEs in a unified manner in the NSACF.

[0044] For example, this aspect provides a mechanism to accommodate the new attribute "maximum number of UEs with at least one PDU session / PDN connection" defined by the GSMA per network slice that UEs (both 5GS UEs and EPS UEs) can use simultaneously by configuring the AMF and SMF with attribute details for monitoring and limiting the number of UEs in a unified manner in the NSACF.

[0045] Network slicing allows configuring multiple tailored dedicated logical networks based on customer requirements on a shared infrastructure. A network slice is identified by a Single Network Slice Selection Assistance Information (S-NSSAI). The S-NSSAI contains a Slice Service Type (SST) and possibly a Slice Differentiator (SD) to distinguish between the same SST customized for different groups / purposes. A PDU session belongs to only one specific network slice instance per PLMN.

[0046] GSMA NG.116 (Non-Patent Document 10) provides a Generic Network Slice Template (GST), which is a set of attributes that can characterize the type of network slice. A NEST is a GST filled with assigned values ​​to represent the requirements of a customer application or use case. A UE can use a network slice (S-NSSAI) that meets the customer requirements, represented by the attributes and parameter values.

[0047] The Network Slice Admission Control (NSAC) controls the number of registered UEs per network slice and the number of PDU sessions per network slice. The Network Slice Admission Control Function (NSACF) implements NSAC on the S-NSSAI that is the target of NSAC by coordinating with the AMF and SMF.

[0048] Assume that 5GS supports EPS interworking for a set of network slice(s). In this scenario, the attribute "maximum number of UEs with at least one PDU session / PDN connection" corresponds to 5GS network slice(s). These network slices are used simultaneously by UEs (both 5GS UEs and EPS UEs), allowing the total number limit to be applied in a unified manner in both 5GS and EPS.

[0049] The attribute "maximum number of UEs with at least one PDU session / PDN connection" may describe (or mean, indicate, or relate to) the maximum number of UEs that can use a network slice simultaneously with at least one PDU session / PDN connection (or at least one of a PDU session and a PDN connection).

[0050] (First Example of the First Aspect) This embodiment provides a mechanism for configuring the AMF to recognize network slice(s) having details of the new attribute "Maximum number of UEs with at least one PDU session / PDN connection" defined by GSMA and the existing attribute "UEs registered with 5GS", including the attribute details, and for performing a verification and update procedure of the number of UEs available per S-NSSAI for network slice(s) that match one of the attributes and are subject to NSAC during the registration procedure.

[0051] The attribute "UEs registered with 5GS" may be referred to in this disclosure as "Maximum UEs" or an older attribute. "The present disclosure" may mean at least one aspect.

[0052] In the present disclosure, in the procedure for checking and updating the number of UEs available for each S-NSSAI, a check of the total number of registered UEs can be performed.

[0053] A detailed process of a first example relating to the first aspect is described below with reference to Figure 1. Figure 1 shows a procedure for configuring an AMF to recognize network slice(s) (S-NSSAI(s)) with different attributes and applying NSAC during the registration procedure.

[0054] Step 1: AMF 70 is configured to recognize network slice(s) (S-NSSAI(s)) with its attributes, such as UE 3 registered with 5GS and UE 3 having at least one PDU session or PDN connection, to perform NSAC based on the slice type and its attributes. For example, S-NSSAI#1 (UE registered with 5GS) and S-NSSAI#2 (UE having at least one PDU session / PDN connection) are two network slices with specific attributes, which are subject to NSAC.

[0055] In the present disclosure, for example, S-NSSAI#1 may have or be associated with the attribute "UE registered in 5GS."

[0056] In the present disclosure, for example, S-NSSAI#2 may have or be associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0057] In the present disclosure, for example, AMF70 may be configured to recognize (or otherwise determine) the attribute(s) of the network slice(s) (or S-NSSAI(s)).

[0058] In the present disclosure, for example, AMF 70 may be configured to recognize that S-NSSAI#1 has or is associated with the attribute "UE registered with 5GS," and AMF 70 may be configured to recognize that S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0059] In the present disclosure, for example, AMF70 can recognize or understand that S-NSSAI#1 has or is associated with the attribute "UE registered in 5GS" and S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0060] In the present disclosure, for example, AMF70 may be configured with information regarding attributes (e.g., "UEs registered with 5GS" and "maximum number of UEs with at least one PDU session / PDN connection") for each network slice (or S-NSSAI). In the present disclosure, the information regarding the attributes may indicate that S-NSSAI#1 has or is associated with the attribute "UEs registered with 5GS," and / or the information regarding the attributes may indicate that S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0061] In the present disclosure, for example, based on information regarding attributes, AMF70 can determine which network slices (or S-NSSAIs) have or are associated with which attributes.

[0062] In the present disclosure, for example, the AMF 70 may pre-store information about the attributes or may receive information about the attributes from other network nodes.

[0063] In the present disclosure, for example, when a registration procedure for S-NSSAI is performed, the attribute "UE registered with 5GS" may indicate that a count or update of the number of UEs (or NSAC related to the number of UEs) has been performed.

[0064] In the present disclosure, for example, the attribute "maximum number of UEs with at least one PDU session / PDN connection" may indicate that an aggregation or update of the number of UEs (or NSAC related to the number of UEs) is performed when a PDU session establishment procedure for S-NSSAI is performed.

[0065] In the present disclosure, for example, the attribute "maximum number of UEs with at least one PDU session / PDN connection" may indicate that when a registration procedure for S-NSSAI is performed, no counting or updating of the number of UEs (or NSAC related to the number of UEs) is performed, but may indicate that when a PDU session establishment procedure for S-NSSAI is performed, counting or updating of the number of UEs (or NSAC related to the number of UEs) is performed.

[0066] In the present disclosure, for example, the attribute "maximum number of UEs with at least one PDU session / PDN connection" can be expressed as "maximum number of UEs with at least one PDU session in 5GS and at least one PDN connection in EPS", or "maximum number of UEs with at least one PDU session and PDN connection", or "maximum number of UEs with at least one PDU session or PDN connection", or "UEs with at least one PDU session / PDN connection", or "UEs with at least one PDU session".

[0067] For network slice(s) whose attribute is "maximum number of UEs with at least one PDU session / PDN connection", UEs 3 that are registered with the 5GS network slice but do not have a PDU session established are not counted. Also, the attribute "maximum number of UEs with at least one PDU session / PDN connection" is not used together with the attribute "maximum number of UEs".

[0068] Step 2: The NSSAI is a collection of S-NSSAI(s). The Requested NSSAI is the NSSAI provided by the UE 3 to the serving PLMN during the registration procedure. Here, the UE 3 provides the Requested NSSAI to the AMF 70 as part of the Registration Request, and the Requested NSSAI includes two S-NSSAIs (S-NSSAI#1 and S-NSSAI#2).

[0069] For example, UE3 may send a Registration Request message with a Requested NSSAI including S-NSSAI#1 and S-NSSAI#2.

[0070] Optionally, if the serving PLMN is not the home PLMN of the UE 3, the UE 3 may include a mapping of Requested NSSAIs, which maps each S-NSSAI of the Requested NSSAI to an S-NSSAI of the HPLMN.

[0071] Step 3: Steps 2 to 19c of the registration procedure in TS23.502 (Non-Patent Document 3) and FIG. 4.2.2.2.2-1 are performed.

[0072] Step 4: The AMF 70 is configured with information indicating which network slices are subject to the NSAC.

[0073] For example, AMF70 may determine (or confirm, or verify) whether the S-NSSAI(s) (e.g., S-NSSAI#2) in the Requested NSSAI of step 2 is associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection."

[0074] Further, AMF70 may determine (or confirm, or verify) whether the S-NSSAI(s) (e.g., S-NSSAI#2) in the Requested NSSAI of step 2 is subject to NSAC.

[0075] If the S-NSSAI(s) in the Requested NSSAI of step 2 (e.g., S-NSSAI#2) are associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" and / or are subject to NSAC (e.g., if AMF 70 determines that the S-NSSAI(s) in the Requested NSSAI of step 2 (e.g., S-NSSAI#2) are associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" and are subject to NSAC), AMF 70 performs option A of FIG. 1. Otherwise, if the S-NSSAI(s) in the Requested NSSAI of step 2 (e.g., S-NSSAI#1) are associated with the attribute "UEs registered with 5GS" and are subject to NSAC, AMF 70 performs option B of FIG. 1. In the present disclosure, S-NSSAI#1 and S-NSSAI#2 can be subject to NSAC.

[0076] For example, if S-NSSAI#1 is associated with the attribute "UE registered with 5GS" and S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" and / or S-NSSAI#1 and S-NSSAI#2 are subject to NSAC, AMF70 can execute option A of Figure 1.

[0077] For example, if S-NSSAI#1 and S-NSSAI#2 are associated with the attribute "UE registered in 5GS" and / or S-NSSAI#1 and S-NSSAI#2 are subject to NSAC, AMF70 may execute option B of Figure 1.

[0078] The AMF 70 activates confirmation of the number of UEs per network slice. The AMF 70 activates an update procedure to update the number of UEs registered in an S-NSSAI having the attribute "UE registered in 5GS" and subject to NSAC. For example, the AMF 70 may activate a confirmation and update procedure of the number of available UEs per network slice and update the number of UEs registered in an S-NSSAI having the attribute "UE registered in 5GS" and subject to NSAC. In the present disclosure, the confirmation and update procedure of the number of available UEs per network slice may be expressed as a confirmation and update procedure of the number of available UEs per S-NSSAI.

[0079] There may be multiple NSACFs 77 for different S-NSSAIs that are the subject of NSAC, and therefore the AMF 70 checks the number of UEs 3 available per network slice and sends update requests to multiple NSACFs 77.

[0080] (Option A) Step 5a: Network slices (e.g., S-NSSAI#2) that are associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" but for which no PDU session has yet been established are not considered for NSAC during the registration procedure. Therefore, at this stage, only network slice(s) (e.g., S-NSSAI#1) that are associated with the attribute "UEs registered with 5GS" and are subject to NSAC are considered.

[0081] The AMF 70 uses the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation to share the UE ID, value(s) of S-NSSAI(s) and Access Type information with the NSACF 77 to increase the number of UEs 3 registered to the same S-NSSAI.

[0082] In this disclosure, the value(s) of S-NSSAI(s) may be expressed as S-NSSAI(s). For example, AMF 70 may send an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI #1 to NSACF 77.

[0083] For example, AMF70 may send an Nnsacf_NSAC_NumOfUEsUpdate_Request message to perform a procedure to check and update the number of UEs available per S-NSSAI.

[0084] For example, AMF70 may not send (or may continue to send) an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 if S-NSSAI#2 has the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0085] For example, AMF70 may not include S-NSSAI#2 in the Nnsacf_NSAC_NumOfUEsUpdate_Request message if S-NSSAI#2 has the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0086] Step 6a: The NSACF 77 checks the tally of the number of UEs 3 registered per network slice (i.e., S-NSSAI), and if the total number does not exceed the maximum limit, increases the total number and allows the UEs 3 to use the same S-NSSAI.

[0087] For example, NSACF77 checks the tally of the number of UE3s registered for S-NSSAI#1, and if the total number does not exceed the maximum limit, increases the total number and allows UE3 to use S-NSSAI#1.

[0088] For example, NSACF 77 may check the tally of the number of UEs 3 registered for S-NSSAI#1, and if the total number exceeds the maximum limit, may not increase the total number and may not allow UEs 3 to use S-NSSAI#1.

[0089] Step 7a: NSACF 77 uses the Nnsacf_NSAC_NumOfUEsUpdate_Response service operation to notify AMF 70 whether the limit on the maximum number of registered UEs 3 per network slice has been reached. In the present disclosure, the limit on the maximum number of registered UEs per network slice can be expressed as the maximum number of registered UEs per network slice.

[0090] For example, if the maximum number of UEs registered in S-NSSAI#1 has not been reached, NSACF 77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered in S-NSSAI#1 has not been reached. In the present disclosure, "the maximum number of UEs has not been reached" may be expressed as "the maximum number of UEs has not currently been reached."

[0091] For example, if the maximum number of UEs registered in S-NSSAI#1 is reached, NSACF 77 may transmit an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered in S-NSSAI#1 has been reached. In the present disclosure, "the maximum number of UEs has been reached" may be expressed as "the maximum number of UEs is currently reached."

[0092] Step 8a: Upon receiving the response from the NSACF 77, the AMF 70 sends a Registration Accept message to the UE 3, including at least one of an Allowed NSSAI and a Rejected NSSAI. The Allowed NSSAI indicates a set of S-NSSAIs that the UE 3 can use to access services from serving PLMNs in the current Registration Area. The Rejected NSSAI indicates a set of S-NSSAIs that the UE 3 cannot use to access services. The Registration Accept message also includes an Unchecked NSSAI. The Unchecked NSSAI indicates a set of S-NSSAIs that are subject to NSAC and should be confirmed with the NSACF 77 during the PDU session establishment procedure. The Unchecked NSSAI may not be included in the Registration Accept message.

[0093] The Unchecked NSSAI includes a set of S-NSSAIs with the attribute "maximum number of UEs with at least one PDU session / PDN connection," and their availability has not yet been confirmed with the NSACF 77 during the registration procedure if no PDU session has been established to the UE 3. The UE 3 can use the S-NSSAI(s) specified in the Unchecked NSSAI while requesting PDU session establishment as long as the S-NSSAI(s) are within the Allowed NSSAIs, but the availability of the S-NSSAI(s) is known only at the end of the PDU session establishment procedure, after confirmation with the NSACF 77. The Unchecked NSSAI can include S-NSSAI(s) for which the procedure for checking and updating the number of available UEs per S-NSSAI has not been performed. The Unchecked NSSAI can include S-NSSAI(s) for which the procedure for checking and updating the number of available UEs per S-NSSAI has not been performed during the registration procedure. The Unchecked NSSAI may be a list of S-NSSAI(s) for which the procedure for checking and updating the number of available UEs per S-NSSAI has not been performed. The Unchecked NSSAI may be a list of S-NSSAI(s) for which the procedure for checking and updating the number of available UEs per S-NSSAI has not been performed during the registration procedure. The AMF 70 may store the Unchecked NSSAI. When the UE 3 reselects a cell for a TAI that does not belong to the registered TAI and performs a mobility registration procedure, the old AMF includes the Unchecked NSSAI in a message to the new AMF. The new AMF stores the Unchecked NSSAI and updates the UE count during the PDU session establishment procedure for the S-NSSAI stored in the Unchecked NSSAI.

[0094] Here, the serving PLMN (e.g., AMF 70) sends the Allowed NSSAIs (e.g., including S-NSSAI#1 and S-NSSAI#2) and the Unchecked NSSAIs (e.g., including S-NSSAI#2) to the UE 3 in a Registration Accept message. The Allowed NSSAIs may include S-NSSAI#1 and S-NSSAI#2. The Unchecked NSSAIs may include S-NSSAI#2.

[0095] For example, if AMF70 determines in step 4 that S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" (or if AMF70 executes option A), AMF70 may send an Unchecked NSSAI including S-NSSAI#2 to UE3.

[0096] If S-NSSAI#2 is the subject of an NSSAA (or NSSAA procedure), the Registration Accept message includes the Allowed NSSAI set to (or including) S-NSSAI#1, the Pending NSSAI set to (or including) S-NSSAI#2, and the Unchecked NSSAI set to (or including) S-NSSAI#2. If the NSSAA procedure is completed successfully, AMF70 sends a Configuration Update command with the Allowed NSSAI set to S-NSSAI#1 and S-NSSAI#2, and, in some cases, with the Unchecked NSSAI set to S-NSSAI#2. Alternatively, if the NSSAA procedure is completed successfully, AMF70 can send a Configuration Update command with the Allowed NSSAI set to S-NSSAI#1 and the Unchecked NSSAI set to S-NSSAI#2. If the NSSAA procedure fails, AMF70 sends the extended rejected NSSAI set to S-NSSAI#2. If UE3 receives a configuration update command with an extended rejected NSSAI, UE3 deletes S-NSSAI#2 from the Unchecked NSSAI.

[0097] For example, if AMF70 receives an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#1 has been reached, AMF70 may send a Registration Accept message having an Allowed NSSAI including S-NSSAI#2, a Rejected NSSAI including S-NSSAI#1, and / or an Unchecked NSSAI including S-NSSAI#2.

[0098] In step 4, if AMF70 determines that S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection", AMF70 may include an Unchecked NSSAI including S-NSSAI#2 in the Registration Accept message.

[0099] In step 4, if AMF70 determines that S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection", AMF70 may include an Allowed NSSAI including S-NSSAI#2 in the Registration Accept message.

[0100] For example, in addition to or instead of sending the Unchecked NSSAI, AMF70 may send a Registration Accept message including information indicating that verification of the count of the number of UE3s registered for S-NSSAI#2 has not been performed.

[0101] For example, information indicating that the count of the number of UEs 3 registered for S-NSSAI#2 is not checked may have a similar role to Unchecked NSSAI in the present disclosure.

[0102] (Option B) Step 5b: If two S-NSSAIs (e.g., S-NSSAI#1 and S-NSSAI#2) in the Requested NSSAI are associated with the same attribute "UE registered in 5GS" and are considered to be subject to NSAC, then both slices (S-NSSAI#1 and S-NSSAI#2) are considered for the verification and update procedure of the number of UEs available per network slice in this case.

[0103] The AMF 70 uses the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation to share the UE ID, S-NSSAI(s) value, and Access Type information with the NSACF 77 and increase the number of UEs 3 registered to the same S-NSSAI(s).

[0104] For example, AMF70 may send an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#1 and S-NSSAI#2 to NSACF77.

[0105] Step 6b: The NSACF 77 checks the total number of UEs 3 registered per network slice (i.e., S-NSSAI), and if the total number does not exceed the maximum limit, increases the total number and allows the UEs 3 to use the same S-NSSAI. For example, the NSACF 77 checks the total number of UEs 3 registered for S-NSSAI#1 and S-NSSAI#2, and if the total number does not exceed the maximum limit, increases the total number and allows the UEs 3 to use S-NSSAI#1 and S-NSSAI#2. For example, the NSACF 77 checks the total number of UEs 3 registered for S-NSSAI#1 and S-NSSAI#2, and if the total number exceeds the maximum limit, does not increase the total number and does not allow the UEs 3 to use S-NSSAI#1 and S-NSSAI#2. The NSACF 77 can perform NSAC for S-NSSAI#1 and S-NSSAI#2.

[0106] Step 7b: The NSACF 77 uses the Nnsacf_NSAC_NumOfUEsUpdate_Response service operation to notify the AMF 70 whether the limit on the maximum number of registered UEs 3 per network slice has been reached.

[0107] For example, if the maximum number of UEs registered in S-NSSAI#1 has not been reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered in S-NSSAI#1 has not been reached.

[0108] For example, if the maximum number of UEs registered to S-NSSAI#2 has not been reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#2 has not been reached.

[0109] For example, if the maximum number of UEs registered to S-NSSAI#1 is reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#1 has been reached.

[0110] For example, if the maximum number of UEs registered to S-NSSAI#2 is reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#2 has been reached.

[0111] For example, if the maximum number of UEs registered in S-NSSAI#1 has not been reached and the maximum number of UEs registered in S-NSSAI#2 has not been reached, NSACF77 can send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered in S-NSSAI#1 has not been reached and information indicating that the maximum number of UEs registered in S-NSSAI#2 has not been reached.

[0112] For example, when the maximum number of UEs registered in S-NSSAI#1 has been reached and the maximum number of UEs registered in S-NSSAI#2 has been reached, NSACF77 can send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered in S-NSSAI#1 has been reached and information indicating that the maximum number of UEs registered in S-NSSAI#2 has been reached.

[0113] For example, if the maximum number of UEs registered in S-NSSAI#1 has not been reached and the maximum number of UEs registered in S-NSSAI#2 has been reached, NSACF77 can send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered in S-NSSAI#1 has not been reached and information indicating that the maximum number of UEs registered in S-NSSAI#2 has been reached.

[0114] For example, if the maximum number of UEs registered in S-NSSAI#1 has been reached and the maximum number of UEs registered in S-NSSAI#2 has not been reached, NSACF77 can send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered in S-NSSAI#1 has been reached and information indicating that the maximum number of UEs registered in S-NSSAI#2 has not been reached.

[0115] Step 8b: Upon receiving the response from the NSACF 77, the AMF 70 sends at least one of an Allowed NSSAI, which indicates a set of S-NSSAIs that the UE 3 can use to access services from the serving PLMN in the current Registration Area, and a Rejected NSSAI, which indicates a set of S-NSSAIs that the UE 3 cannot use to access services. Here, the serving PLMN (e.g., AMF 70) sends the Allowed NSSAIs (e.g., including S-NSSAI#1 and S-NSSAI#2) to the UE 3 in a Registration Accept message.

[0116] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#1 has not been reached, AMF70 can send a Registration Accept message having an Allowed NSSAI including S-NSSAI#1.

[0117] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#1 has been reached, AMF70 may send a Registration Accept message having a Rejected NSSAI including S-NSSAI#1.

[0118] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#2 has not been reached, AMF70 may send a Registration Accept message having an Allowed NSSAI including S-NSSAI#2.

[0119] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#2 has been reached, AMF70 may send a Registration Accept message having a Rejected NSSAI including S-NSSAI#2.

[0120] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#1 has not been reached and information indicating that the maximum number of UEs registered to S-NSSAI#2 has not been reached, AMF70 can send a Registration Accept message having an Allowed NSSAI including S-NSSAI#1 and S-NSSAI#2.

[0121] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#1 has been reached and information indicating that the maximum number of UEs registered to S-NSSAI#2 has been reached, AMF70 can send a Registration Accept message having a Rejected NSSAI including S-NSSAI#1 and S-NSSAI#2.

[0122] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#1 has not been reached and information indicating that the maximum number of UEs registered to S-NSSAI#2 has been reached, AMF70 can send a Registration Accept message having an Allowed NSSAI including S-NSSAI#1 and a Rejected NSSAI including S-NSSAI#2.

[0123] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered for S-NSSAI#1 has been reached and information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached, AMF70 can send a Registration Accept message having a Rejected NSSAI including S-NSSAI#1 and an Allowed NSSAI including S-NSSAI#2.

[0124] (Modification 1 of the first embodiment related to the first aspect) In step 2 of the first embodiment of the first aspect of Figure 1, the UE 3 provides a Requested NSSAI. In some cases, the UE 3 may not provide a Requested NSSAI. In that case, the network identifies an S-NSSAI suitable for the UE 3 and proceeds with the registration procedure.

[0125] (Second Example of the First Aspect) This embodiment configures an SMF to recognize network slice(s) that have details of the new attribute "maximum number of UEs with at least one PDU session / PDN connection" defined by GSMA and the existing attribute "UEs registered with 5GS", including the attribute details, and includes a mechanism for performing, during a PDU session establishment procedure, a verification and update procedure of the number of UEs available per S-NSSAI of network slice(s) that conform to the attribute "maximum number of UEs with at least one PDU session / PDN connection" and are subject to NSAC.

[0126] A detailed process of a second example embodiment relating to the first aspect is described below with reference to Figure 2. Figure 2 shows a procedure for configuring an SMF to recognize network slice(s) with different attributes (S-NSSAI) and applying NSAC during a PDU session establishment procedure.

[0127] The process of the second embodiment of the first aspect may be performed after the process of the first embodiment of each aspect, for example, the process of the second embodiment of the first aspect may be performed after step 8a of the first embodiment of the first aspect.

[0128] Step 1: SMF 71 is configured to recognize network slice(s) (S-NSSAI) with its attributes, such as UE 3 registered with 5GS and UE 3 having at least one PDU session or PDN connection, to perform NSAC based on the slice type and its attributes. For example, S-NSSAI#1 (UE registered with 5GS) and S-NSSAI#2 (UE having at least one PDU session / PDN connection) are two network slices with specific attributes, which are subject to NSAC.

[0129] In the present disclosure, for example, SMF71 may be configured to recognize (or may be configured to determine, or may be configured to verify) attributes of network slice(s) (or S-NSSAI(s)).

[0130] In the present disclosure, for example, SMF71 can be configured to recognize that S-NSSAI#1 has or is associated with the attribute "UE registered in 5GS" and that S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0131] In the present disclosure, for example, SMF71 can recognize or understand that S-NSSAI#1 has or is associated with the attribute "UE registered in 5GS" and that S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0132] In the present disclosure, for example, SMF71 can be configured with information regarding attributes (e.g., "UE registered with 5GS" and "UE with at least one PDU session / PDN connection") for each network slice (or S-NSSAI).

[0133] In the present disclosure, for example, based on information regarding attributes, SMF71 can determine which network slices (or S-NSSAIs) have or are associated with which attributes.

[0134] In the present disclosure, for example, the SMF 71 may pre-store information about the attributes or may receive information about the attributes from other network nodes.

[0135] Step 2: UE3 provides S-NSSAI (e.g., S-NSSAI#2) and / or Unchecked NSSAI (e.g., including S-NSSAI#2) to SMF71 as part of a PDU session establishment request. For example, UE 3 may send a PDU session establishment request message that includes at least one S-NSSAI with which UE 3 desires to establish a PDU session and that includes an Unchecked NSSAI.

[0136] For example, UE3 may send a PDU session establishment request message that includes at least S-NSSAI#2 with which UE3 desires to establish a PDU session, and has an Unchecked NSSAI that includes S-NSSAI#2.

[0137] For example, UE3 may select S-NSSAI#2 from the Allowed NSSAIs received in step 8a of FIG.

[0138] For example, UE3 may select S-NSSAI#2 from at least one of the Allowed NSSAI and the Unchecked NSSAI received in step 8a of Figure 1. The S-NSSAI(s) included in the PDU session establishment request message may be included in at least one of the Allowed NSSAI and the Unchecked NSSAI received in step 8a of Figure 1.

[0139] Step 2 can be separated into two parts:

[0140] The UE 3 may send a UL NAS Transport message with an S-NSSAI (e.g., S-NSSAI#2), a payload container, and / or an Unchecked NSSAI (e.g., including S-NSSAI#2) to the AMF 70. The payload container includes a PDU session establishment request message.

[0141] When AMF70 receives the UL NAS Transport message, AMF70 can send a PDU session establishment request message and / or an Nsmf_PDUSession_CreateSMContext Request message including an Unchecked NSSAI (e.g., including S-NSSAI#2) to SMF71.

[0142] In one embodiment, the PDU session establishment request message may include an Unchecked NSSAI (eg, including S-NSSAI#2).

[0143] Optionally, if the serving PLMN is not the home PLMN of the UE 3, the UE 3 may include an Allowed NSSAI / Unchecked NSSAI mapping, which maps each S-NSSAI of the Allowed NSSAI / Unchecked NSSAI to an S-NSSAI of the HPLMN.

[0144] The Unchecked NSSAI may not be included in the PDU session establishment request message. For example, in step 8a of Figure 1, if the UE 3 does not receive the Unchecked NSSAI from the AMF 70, the UE 3 may not send the Unchecked NSSAI.

[0145] For example, if UE3 receives information in step 8a of FIG. 1 indicating that verification of the count of the number of UE3s registered for S-NSSAI#2 has not been performed, UE3 may include that information in the PDU session establishment request message.

[0146] Step 3: Steps 2 to 10b of the PDU session establishment procedure in TS23.502 (Non-Patent Document 3), Figure 4.3.2.2.1-1, are performed.

[0147] Step 4: The SMF 71 is configured with information indicating which network slices are subject to the NSAC.

[0148] For example, SMF71 may determine whether the S-NSSAI(s) (e.g., S-NSSAI#2) in the Unchecked NSSAI (or S-NSSAI(s) (e.g., S-NSSAI#2) in the PDU Session Establishment Request) in step 2 is associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection".

[0149] Furthermore, SMF71 can determine whether the S-NSSAI(s) (e.g., S-NSSAI#2) in the Unchecked NSSAI (or S-NSSAI(s) (e.g., S-NSSAI#2)) in step 2 is subject to NSAC.

[0150] If the S-NSSAI(s) (e.g., S-NSSAI#2) in the Unchecked NSSAI of step 2 (or the S-NSSAI(s) (e.g., S-NSSAI#2) in the PDU Session Establishment Request) are associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" and are subject to NSAC (e.g., if SMF71 determines that the S-NSSAI(s) (e.g., S-NSSAI#2) in the Unchecked NSSAI of step 2 (or the S-NSSAI(s) (e.g., S-NSSAI#2) in the PDU Session Establishment Request) are associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" and / or are subject to NSAC), SMF71 performs option A of Figure 2. Otherwise, SMF71 performs option B of Figure 2.

[0151] For example, if SMF71 does not receive an Unchecked NSSAI, SMF71 can determine whether S-NSSAI#2 in the PDU Session Establishment Request is associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection" and / or is subject to NSAC.

[0152] For example, if SMF71 receives information indicating that confirmation of the number of UEs registered for S-NSSAI#2 has not been performed, SMF71 can determine whether S-NSSAI#2 in the PDU Session Establishment Request is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" and / or is subject to NSAC.

[0153] The SMF 71 activates the procedure for checking and updating the number of available UEs per network slice to update the number of UEs that are registered in the S-NSSAI with the attribute "maximum number of UEs with at least one PDU session / PDN connection" and are subject to NSAC. In the present disclosure, the SMF 71 can perform the procedure for checking and updating the number of available UEs per network slice by using the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation or by sending a Nnsacf_NSAC_NumOfUEsUpdate_Request message.

[0154] For example, if S-NSSAI#2 is subject to NSAC and / or S-NSSAI#2 is associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection", SMF71 may execute option A of Figure 2.

[0155] For example, if S-NSSAI#2 is subject to NSAC and / or is associated with the attribute "UE registered with 5GS", SMF71 may perform option B of Figure 2.

[0156] There may be multiple NSACFs 77 for different S-NSSAIs that are the subject of NSAC, and therefore the SMF 71 issues confirmation and update requests for the number of UEs available per network slice to multiple NSACFs 77.

[0157] (Option A) Step 5a: SMF71 selects S-NSSAI(s) (e.g., S-NSSAI#2) that are associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection" in the Unchecked NSSAI (or in the PDU session establishment request message) and are subject to NSAC.

[0158] The SMF71 uses the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation to share the UE ID, PDU Session ID, value(s) of S-NSSAI(s) and Access Type information with the NSACF77 to increase the number of UEs 3 registered to the same S-NSSAI.

[0159] For example, SMF 71 can send an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 to NSACF 77.

[0160] For example, if SMF 71 does not receive an Unchecked NSSAI from UE 3, SMF 71 can determine whether S-NSSAI#2 included in the PDU session establishment request message has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" based on the configuration mentioned in step 1. If SMF 71 determines that S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," SMF 71 can send an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 to NSACF 77.

[0161] For example, if the SMF 71 receives information indicating that a check of the count of registered UEs 3 for S-NSSAI#2 has not been performed, the SMF 71 can determine whether the S-NSSAI#2 included in the PDU session establishment request message has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" based on the configuration mentioned in step 1. If the SMF 71 determines that the S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," the SMF 71 can send an Nnsacf_NSAC_NumOfUEsUpdate_Request message including the S-NSSAI#2 to the NSACF 77.

[0162] Step 6a: The NSACF 77 checks the tally of the number of UEs 3 registered per network slice (i.e., S-NSSAI), and if the total number does not exceed the maximum limit, increases the total number and allows the UEs 3 to use the same S-NSSAI.

[0163] For example, when NSACF 77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 from SMF 71, NSACF 77 can check the count of the number of UEs 3 registered for S-NSSAI#2.

[0164] For example, NSACF77 checks the tally of the number of UE3s registered for S-NSSAI#2, and if the total number does not exceed the maximum limit, increases the total number and allows UE3 to use S-NSSAI#2.

[0165] For example, NSACF77 may check the tally of the number of UE3s registered for S-NSSAI#2, and if the total number exceeds the maximum limit, may not increase the total number and may not allow UE3s to use S-NSSAI#2.

[0166] Step 7a: The NSACF 77 uses the Nnsacf_NSAC_NumOfUEsUpdate_Response service operation to notify the SMF 71 whether the limit on the maximum number of registered UEs 3 per network slice has been reached.

[0167] For example, if the maximum number of UEs registered to S-NSSAI#2 has not been reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#2 has not been reached.

[0168] For example, if the maximum number of UEs registered to S-NSSAI#2 is reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#2 has been reached.

[0169] Step 8a: Upon receiving the response from the NSACF 77, the SMF 71 sends either a PDU Session Establishment Accept message by including the S-NSSAI from the Unchecked NSSAI received in step 3, or a PDU Session Establishment Reject message with a cause indicating that "the maximum number of UEs with at least one PDU session per S-NSSAI has been reached" to the AMF 70. The reason may indicate that the number of UEs with at least one PDU session / PDN connection per S-NSSAI has been reached.

[0170] For example, SMF71 can send a PDU Session Establishment Accept message including S-NSSAI#2.

[0171] For example, if the response from NSACF77 includes information indicating that the maximum number of UEs registered to S-NSSAI#2 has not been reached, SMF71 can send a PDU Session Establishment Accept message including S-NSSAI#2.

[0172] For example, SMF71 can send a PDU Session Establishment Reject message including S-NSSAI#2.

[0173] For example, the PDU Session Establishment Reject message may include a reason indicating that "the maximum number of UEs with at least one PDU session per S-NSSAI has been reached."

[0174] For example, SMF71 may send a PDU Session Establishment Reject message including S-NSSAI#2 with a reason indicating that "the maximum number of UEs with at least one PDU session per S-NSSAI has been reached."

[0175] For example, in the present disclosure, the reason may be expressed as a reason value or a rejection reason.

[0176] For example, if the response from NSACF77 includes information indicating that the maximum number of UEs registered to S-NSSAI#2 has been reached, SMF71 can send a PDU Session Establishment Reject message including S-NSSAI#2.

[0177] Sending the PDU Session Establishment Accept message and sending the PDU Session Establishment Reject message can be performed using Namf_Communication_N1N2MessageTransfer.

[0178] Step 9a: The AMF 70 sends the message received from the SMF 71 to the UE 3. Here, the AMF 70 sends a PDU Session Establishment Reject message including a Rejected S-NSSAI (e.g., S-NSSAI#2) with the reason "The maximum number of UEs with at least one PDU session per S-NSSAI has been reached."

[0179] When the AMF 70 receives a PDU Session Establishment Accept message from the SMF 71, the AMF 70 can send a PDU Session Establishment Accept message to the UE 3.

[0180] If the AMF 70 receives a PDU Session Establishment Reject message from the SMF 71, the AMF 70 may send a PDU Session Establishment Reject message to the UE 3.

[0181] (Option B) Step 5b: If the S-NSSAI(s) (e.g., S-NSSAI#2) are associated with the attribute "UEs registered in 5GS" and the number of UEs for the S-NSSAI(s) (e.g., S-NSSAI#2) has already been tallied in the registration procedure, or if the S-NSSAI(s) (e.g., S-NSSAI#2) are not subject to NSAC, the S-NSSAI(s) are considered in this case and they are not subject to NSAC again.

[0182] The SMF 71 sends to the AMF 70 either a PDU Session Establishment Accept message by including the S-NSSAI from the Allowed NSSAI received in step 3, or a PDU Session Establishment Reject message including a reason if the PDU session establishment failed in step 3. The reason may indicate that the PDU session establishment failed.

[0183] For example, if SMF71 determines, based on the configuration mentioned in step 1, that S-NSSAI#2 has or is associated with the attribute "UE registered in 5GS", SMF71 may not perform the Nnsacf_NSAC_NumOfUEsUpdate_Response service operation for S-NSSAI#2.

[0184] SMF71 can then send a PDU Session Establishment Accept message including S-NSSAI#2 to AMF70 if the PDU session establishment is completed successfully in step 3.

[0185] If the PDU session establishment fails in step 3, SMF71 can send a PDU Session Establishment Reject message including S-NSSAI#2 to AMF70.

[0186] Sending the PDU Session Establishment Accept message and sending the PDU Session Establishment Reject message can be performed using Namf_Communication_N1N2MessageTransfer.

[0187] Step 6b: The AMF 70 sends the message received from the SMF 71 to the UE 3. Here, the AMF 70 sends a PDU Session Establishment Accept message having an S-NSSAI value (e.g., S-NSSAI#2).

[0188] When the AMF 70 receives a PDU Session Establishment Accept message from the SMF 71, the AMF 70 can send a PDU Session Establishment Accept message to the UE 3.

[0189] If the AMF 70 receives a PDU Session Establishment Reject message from the SMF 71, the AMF 70 may send a PDU Session Establishment Reject message to the UE 3.

[0190] (Modification 1 of the second embodiment related to the first aspect) In step 2 of the second embodiment of the first aspect of Figure 2, the UE 3 provides an S-NSSAI and / or an Unchecked NSSAI. In some cases, the UE 3 may not provide an S-NSSAI and / or an Unchecked NSSAI. In that case, the network identifies an S-NSSAI suitable for the UE 3 and proceeds with the PDU session establishment procedure.

[0191] (Modification 2 of the second embodiment related to the first aspect) In step 1 of the second embodiment related to the first aspect of FIG. 2, the SMF 71 is configured to recognize network slice(s) with attribute details for executing / activating NSAC based on the slice type and its attributes. Because the AMF 70 normally maintains configuration data as a control signaling node, the AMF 70 can be configured in step 1 to recognize network slice(s) with attribute details for executing / activating NSAC on behalf of the SMF 71. In this case, the AMF 70 can share configuration details of the S-NSSAI in the Allowed NSSAI and / or Unchecked NSSAI with the SMF 71 to execute / activate a procedure for checking and updating the number of UEs available per network slice. Then, a procedure similar to step 5 described in the second embodiment related to the first aspect of FIG. 2 is performed. The configuration details of the S-NSSAI(s) may include information (e.g., S-NSSAI(s)) indicating attributes for each network slice(s). The configuration details of the S-NSSAI(s) may include information indicating that the S-NSSAI#1 has or is associated with the attribute "UE registered in 5GS", as well as information indicating that the S-NSSAI#1 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection".

[0192] For example, AMF 70 can send the configuration details of S-NSSAI(s) to SMF 71 using existing message(s) or new message(s) between AMF 70 and SMF 71. SMF 71 can then perform the process(es) in step 4 based on the configuration details of the received S-NSSAI.

[0193] According to this variant, SMF71 may perform the process of step 4 based on the configuration details of the received S-NSSAI(s) if SMF71 is not configured to recognize the network slice(s) (S-NSSAI(s)) in its attributes.

[0194] (Modification 3 of the second embodiment related to the first aspect) In step 7a, if SMF71 receives an Nnsacf_NSAC_NumOfUEsUpdate_Response message indicating that the update request for some UEs was successful (e.g., if SMF71 receives a response from NSACF77 containing information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached), SMF71 can include S-NSSAI#2 in the Checked NSSAI in the PDU Session Establishment Accept message and send it to UE3 via AMF70.

[0195] For example, if SMF71 receives a response from NSACF77 containing information indicating that the maximum number of UEs registered for S-NSSAI#2 has been reached, SMF71 can include S-NSSAI#2 in a PDU Session Establishment Accept message and send it to UE3 via AMF70.

[0196] When UE3 receives S-NSSAI#2 in the Checked NSSAI, it deletes S-NSSAI#2 from the Unchecked NSSAI in the memory unit of UE3.

[0197] The Checked NSSAI can indicate the set of S-NSSAIs that have been checked to the NSACF 77 during the PDU session establishment procedure.

[0198] (Modification 4 of the second embodiment related to the first aspect) During the procedure of Figure 2, SMF71 can perform a procedure to check and update the number of PDU sessions available per network slice.

[0199] For example, if SMF71 receives a response from NSACF77 in step 7a indicating that the number of UEs registered for S-NSSAI#2 has not reached the maximum limit, SMF71 can perform a verification and update procedure for the number of PDU sessions available per network slice to update (i.e., increase or decrease) the number of PDU sessions established for S-NSSAI#2.

[0200] For example, if SMF71 receives a response from NSACF77 in step 7a indicating that the number of UEs registered for S-NSSAI#2 has reached the maximum limit, SMF71 may not perform the procedure for checking and updating the number of PDU sessions available per network slice for S-NSSAI#2. If SMF71 does not perform the procedure for checking and updating the number of PDU sessions available per network slice for S-NSSAI#2, SMF71 may perform the process(es) of step 8a of Figure 2.

[0201] For example, in the procedure for checking and updating the number of PDU sessions available per network slice, SMF71 can use the Nnsacf_NSAC_NumOfPDUsUpdate_Request service operation for S-NSSAI#2 (e.g., SMF71 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Request message including S-NSSAI#2 to NSACF77).

[0202] For example, upon receiving the Nnsacf_NSAC_NumOfPDUsUpdate_Request message, the NSACF 77 checks the tally of the number of PDU sessions for S-NSSAI#2, and if the total number does not exceed the maximum limit, it can increase the total number and allow the UE 3 to use S-NSSAI#2. The NSACF 77 can then use the Nnsacf_NSAC_NumOfPDUsUpdate_Response service operation to notify the SMF 71 whether the maximum number of PDU sessions established for S-NSSAI#2 has been reached. The limit on the maximum number of PDU sessions can be expressed as a PDU session maximum number.

[0203] For example, if the maximum number of PDU sessions established for S-NSSAI#2 is reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71, including information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0204] For example, if the maximum number of PDU sessions established for S-NSSAI#2 has not been reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71, including information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has not been reached.

[0205] Upon receiving a response from the NSACF 77, the SMF 71 can send either a PDU Session Establishment Accept message including the S-NSSAI#2 or a PDU Session Establishment Reject message with a reason "maximum number of UEs with at least one PDU session per S-NSSAI has been reached" to the AMF 70. The AMF 70 can send the received PDU Session Establishment Accept message or the received PDU Session Establishment Reject message to the UE 3.

[0206] For example, SMF71 can send a PDU Session Establishment Accept message including S-NSSAI#2.

[0207] For example, if the response from NSACF77 includes information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has not been reached, SMF71 can send a PDU Session Establishment Accept message including S-NSSAI#2.

[0208] For example, SMF71 can send a PDU Session Establishment Reject message including S-NSSAI#2.

[0209] For example, the PDU Session Establishment Reject message may include a reason indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0210] For example, SMF71 may send a PDU Session Establishment Reject message including S-NSSAI#2 with a reason indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0211] For example, if the response from NSACF77 includes information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached, SMF71 can send a PDU Session Establishment Reject message including S-NSSAI#2.

[0212] For example, in the case of option B, SMF71 can perform a procedure to check and update the number of PDU sessions available per network slice.

[0213] (Modification 5 of the second embodiment related to the first aspect) Instead of using the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation, the SMF 71 can use the Nnsacf_NSAC_NumOfPDUsUpdate_Request service operation. For example, the SMF 71 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Request message in step 5a having S-NSSAI#2 and / or an Unchecked NSSAI that includes S-NSSAI#2.

[0214] For example, when the NSACF 77 receives an Nnsacf_NSAC_NumOfPDUsUpdate_Request message including an S-NSSAI#2 and / or an Unchecked NSSAI, the NSACF 77 checks the tally of the number of UEs 3 registered for S-NSSAI#2 (e.g., S-NSSAI#2 included in the Unchecked NSSAI), and if the total number does not exceed the maximum limit, increases the total number and allows the UE 3 to use S-NSSAI#2. If the total number exceeds the maximum limit, the NSACF 77 does not increase the total number and does not allow the UE 3 to use S-NSSAI#2.

[0215] Furthermore, when NSACF77 receives an Nnsacf_NSAC_NumOfPDUsUpdate_Request message including S-NSSAI#2 and / or Unchecked NSSAI, NSACF77 can perform a procedure to verify and update the number of PDU sessions available per network slice.

[0216] For example, NSACF 77 may check the tally of the number of UEs 3 registered for S-NSSAI#2, and if the total number does not exceed the maximum limit, may increase the total number and allow UEs 3 to use S-NSSAI#2. NSACF 77 may then check the tally of the number of PDU sessions established for S-NSSAI#2.

[0217] For example, based on the results of checking the tally of the number of registered UEs 3 and the tally of the number of PDU sessions established for S-NSSAI(s), NSACF 77 can include in the Nnsacf_NSAC_NumOfPDUsUpdate_Response message information indicating whether the maximum number of UEs registered for S-NSSAI#2 has been reached, and information indicating whether the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0218] For example, if the maximum number of UEs registered for S-NSSAI#2 has not been reached and the maximum number of PDU sessions established for S-NSSAI#2 has not been reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71, the message including at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has not been reached.

[0219] For example, if the maximum number of UEs registered for S-NSSAI#2 has been reached and the maximum number of PDU sessions established for S-NSSAI#2 has been reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71, the message including at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0220] For example, if the maximum number of UEs registered for S-NSSAI#2 has been reached and the maximum number of PDU sessions established for S-NSSAI#2 has not been reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71, the message including at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has not been reached.

[0221] For example, if the maximum number of UEs registered for S-NSSAI#2 has not been reached and the maximum number of PDU sessions established for S-NSSAI#2 has been reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71 that includes at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0222] For example, if the response from NSF77 contains information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has not been reached, SMF71 can send a PDU Session Establishment Accept message including S-NSSAI#2.

[0223] For example, SMF71 may send a PDU Session Establishment Reject message including S-NSSAI#2 if the response from NSACF77 includes at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0224] Instead of or in addition to the Unchecked NSSAI, the SMF 71 may include in the Nnsacf_NSAC_NumOfPDUsUpdate_Request message a request to perform the verification and update procedure for the number of UEs available per S-NSSAI for S-NSSAI #2. When the NSACF 77 receives the request, it may verify the tally of the number of UEs 3 registered for S-NSSAI #2.

[0225] (Modification 6 of the second embodiment related to the first aspect) The SMF 71 can include an Unchecked NSSAI including S-NSSAI#2 in the Nnsacf_NSAC_NumOfUEsUpdate_Request message.

[0226] For example, when NSACF 77 receives an Unchecked NSSAI including S-NSSAI#2 from SMF 71, it can check the count of the number of UEs 3 registered for S-NSSAI#2.

[0227] Instead of or in addition to the Unchecked NSSAI, the SMF 71 may include in the Nnsacf_NSAC_NumOfPDUsUpdate_Request message a request to perform the verification and update procedure for the number of UEs available per S-NSSAI for S-NSSAI #2. When the NSACF 77 receives the request, it may verify the tally of the number of UEs 3 registered for S-NSSAI #2.

[0228] In order to distinguish between the Nnsacf_NSAC_NumOfUEsUpdate_Request message from the AMF 70 and the Nnsacf_NSAC_NumOfUEsUpdate_Request message from the SMF 71, the SMF 71 can include information indicating that the Nnsacf_NSAC_NumOfUEsUpdate_Request message was sent from the SMF 71 in the Nnsacf_NSAC_NumOfUEsUpdate_Request message.

[0229] When the NSACF 77 receives information indicating that the Nnsacf_NSAC_NumOfUEsUpdate_Request message has been sent from the SMF 71, the NSACF 77 can check the total number of UEs 3 registered for the S-NSSAI #2.

[0230] For example, information indicating that the Nnsacf_NSAC_NumOfUEsUpdate_Request message was sent from the SMF 71 can be expressed as information indicating that the Nnsacf_NSAC_NumOfUEsUpdate_Request message was not sent from the AMF 70.

[0231] For example, instead of information indicating that a Nnsacf_NSAC_NumOfUEsUpdate_Request message was sent from SMF 71, information indicating that a Nnsacf_NSAC_NumOfUEsUpdate_Request message was sent during the PDU session establishment procedure can be used.

[0232] (Modification 7 of the second embodiment related to the first aspect) The SMF 71 can include an Unchecked NSSAI including S-NSSAI#2 in the Nnsacf_NSAC_NumOfUEsUpdate_Request message.

[0233] For example, when NSACF 77 receives an Unchecked NSSAI including S-NSSAI#2 from SMF 71, it can check the count of the number of UEs 3 registered for S-NSSAI#2.

[0234] If the NSACF 77 determines that the total number of registered UEs 3 for S-NSSAI#2 does not exceed the maximum limit, the NSACF 77 may perform a procedure for checking and updating the number of available UEs per network slice (e.g., the NSACF 77 may check the tally of the number of PDU sessions for S-NSSAI#2). Based on the result of checking the tally of the number of PDU sessions for S-NSSAI#2, the NSACF 77 may perform the process described in Variation 4 of the second embodiment related to the first aspect.

[0235] (Second aspect) This aspect provides a mechanism for supporting the new GSMA-defined attribute "maximum number of UEs with at least one PDU session / PDN connection" for each network slice by configuring the NSACF to recognize network slice(s) having the attribute "maximum number of UEs with at least one PDU session / PDN connection" for monitoring and limiting the total number of UEs in a unified manner.

[0236] For example, this aspect provides a mechanism to accommodate the new GSMA-defined attribute "Maximum number of UEs with at least one PDU session / PDN connection" for each network slice that a UE (both 5GS and EPS UEs) can use simultaneously by configuring the NSACF to recognize network slice(s) having the attribute "Maximum number of UEs with at least one PDU session / PDN connection" for monitoring and limiting the total number of UEs in a unified manner.

[0237] (First Example of the Second Aspect) This embodiment provides a mechanism for performing a verification and update procedure of the number of UEs available per S-NSSAI by configuring the NSACF to maintain a new attribute "maximum number of UEs with at least one PDU session / PDN connection" per network slice during the registration procedure.

[0238] A detailed process of a first embodiment relating to the second aspect will be described below with reference to Figure 3. Figure 3 shows a procedure for configuring an NSACF to recognize network slice(s) (S-NSSAI(s)) with a new attribute "maximum number of UEs with at least one PDU session / PDN connection" and applying the NSAC during the registration procedure.

[0239] Step 1: NSACF77 is configured to recognize network slice(s) (S-NSSAI(s)) with new attribute "Maximum number of UEs with at least one PDU session / PDN connection" configuration data for performing NSAC based on slice type and its attributes.

[0240] In the present disclosure, for example, NSACF77 may be configured to recognize (or determine) attributes of network slice(s) (or S-NSSAI(s)).

[0241] In the present disclosure, for example, NSACF77 can be configured to recognize that S-NSSAI#1 has or is associated with the attribute "UE registered with 5GS" and S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0242] In the present disclosure, for example, NSACF77 can recognize or understand that S-NSSAI#1 has or is associated with the attribute "UE registered in 5GS" and S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0243] In the present disclosure, for example, NSACF77 can be configured with information regarding attributes (e.g., "UE registered with 5GS" and "UE with at least one PDU session / PDN connection") for each network slice (or S-NSSAI).

[0244] In the present disclosure, for example, NSACF77 can determine which network slices (or S-NSSAIs) have or are associated with which attributes based on information about the attributes.

[0245] In the present disclosure, for example, NSACF 77 may pre-store information about attributes or may receive information about attributes from other network nodes.

[0246] For network slice(s) whose attribute is "maximum number of UEs with at least one PDU session / PDN connection", UEs 3 that are registered with the 5GS network slice but do not have a PDU session established are not counted. Also, the new attribute "maximum number of UEs with at least one PDU session / PDN connection" is not used together with the attribute "maximum number of UEs".

[0247] Step 2: NSSAI is a collection of S-NSSAIs. Requested NSSAI is an NSSAI provided by UE3 to the serving PLMN during the registration procedure. Here, UE3 provides the Requested NSSAI to AMF70 as part of the Registration Request, and the Requested NSSAI includes two S-NSSAIs (S-NSSAI#1 and S-NSSAI#2).

[0248] For example, UE3 may send a Registration Request message with a Requested NSSAI including S-NSSAI#1 and S-NSSAI#2. This step 2 may be the same as step 2 in FIG.

[0249] Optionally, if the serving PLMN is not the home PLMN of the UE 3, the UE 3 may include a mapping of Requested NSSAIs, which maps each S-NSSAI of the Requested NSSAI to an S-NSSAI of the HPLMN.

[0250] Step 3: Steps 2 to 19c of the registration procedure in TS23.502 (Non-Patent Document 3) and FIG. 4.2.2.2.2-1 are performed.

[0251] Step 4: The AMF 70 is configured with information indicating which network slices are subject to NSAC. If the S-NSSAI(s) in the Requested NSSAI are subject to NSAC regardless of their attribute parameters, the AMF 70 performs a verification and update procedure of the number of available UEs per network slice.

[0252] There may be multiple NSACFs 77 for different S-NSSAIs that are the subject of NSAC, and therefore the AMF 70 operates the verification and update procedure of the number of UEs available per network slice for multiple NSACFs 77.

[0253] Step 5: The AMF 70 uses the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation to share the UE ID, value of S-NSSAI(s) and Access Type information with the NSACF 77 and increase the number of UEs 3 registered to the same S-NSSAI(s). For example, AMF70 may send an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#1 and S-NSSAI#2 to NSACF77.

[0254] Step 6: With the new attribute configuration data available, the NSACF 77 can identify the network slices associated with the new attribute "Maximum number of UEs with at least one PDU session / PDN connection" and include the PDU session(s) in the Unchecked NSSAI if they are not already established. Step 6 can be triggered by receiving an Nnsacf_NSAC_NumOfUEsUpdate_Request message from the AMF 70.

[0255] The network slice(s) associated with the existing attribute "UE registered in 5GS" are considered for NSAC at this stage. NSACF77 checks the tally of the number of registered UE3s for each network slice associated with the existing attribute, and if the total number does not exceed the maximum limit, increases the total number and allows UE3s to use the same S-NSSAI.

[0256] For example, NSACF77 may determine whether the received S-NSSAI(s) is associated with the attribute "UE registered with 5GS" or the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0257] In this case, because S-NSSAI#1 is associated with the attribute "UE registered with 5GS," NSACF 77 checks the tally of the number of UEs 3 registered for S-NSSAI#1, and if the total number does not exceed the maximum limit, increases the total number and allows the UE 3 to use S-NSSAI#1. For example, if the total number exceeds the maximum limit, NSACF 77 may not increase the total number and may not allow the UE 3 to use S-NSSAI#1.

[0258] For example, in this case, since S-NSSAI#2 has the attribute "maximum number of UEs with at least one PDU session / PDN connection", NSACF77 does not need to check the count of the number of UEs3 registered for S-NSSAI#2.

[0259] For example, if NSACF77 determines that S-NSSAI#2 has the attribute "maximum number of UEs with at least one PDU session / PDN connection" and the received Nnsacf_NSAC_NumOfUEsUpdate_Request message does not include an Unchecked NSSAI containing S-NSSAI#2, NSACF77 does not need to check the count of the number of UEs3 registered for S-NSSAI#2.

[0260] For example, if NSACF77 determines that S-NSSAI#2 has the attribute "maximum number of UEs with at least one PDU session / PDN connection" and the received Nnsacf_NSAC_NumOfUEsUpdate_Request message includes an Unchecked NSSAI that includes S-NSSAI#2, NSACF77 may check the tally of the number of UE3s registered for S-NSSAI#2, or NSACF77 may not check the tally of the number of UE3s registered for S-NSSAI#2.

[0261] An Unchecked NSSAI may be defined by the description of the first aspect, or by the description of the second aspect or any other aspect.

[0262] For example, if the NSACF 77 determines that the S-NSSAI#2 has the attribute "maximum number of UEs with at least one PDU session / PDN connection," the NSACF 77 can determine whether PDU session(s) for the S-NSSAI#2 are established for the UE 3. For example, if the NSACF 77 manages the PDU session(s) established for the S-NSSAI#2 using a UE ID, the NSACF 77 can use the UE ID (e.g., the UE ID identifying the UE 3) included in the received Nnsacf_NSAC_NumOfUEsUpdate_Request message to determine whether PDU session(s) for the S-NSSAI#2 are established for the UE 3. If the NSACF 77 determines that PDU session(s) for the S-NSSAI#2 are not established for the UE 3, the NSACF 77 does not need to check the tally of the number of UEs 3 registered for the S-NSSAI#2. If NSACF77 determines that PDU session(s) for S-NSSAI#2 have been established for UE3, NSACF77 may check the tally of the number of UE3s registered for S-NSSAI#2.

[0263] For example, if NSACF77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 from AMF70 and determines that S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," NSACF77 does not need to check the tally of the number of UEs3 registered for S-NSSAI#2.

[0264] For example, if NSACF77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#1 from AMF70 and determines that S-NSSAI#1 is associated with the attribute "UE registered in 5GS", NSACF77 can check the count of the number of registered UEs3 for S-NSSAI#1.

[0265] For example, when NSACF 77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message from AMF 70, NSACF 77 can determine that the Nnsacf_NSAC_NumOfUEsUpdate_Request message was sent in the registration procedure.

[0266] If the NSACF77 determines that the Nnsacf_NSAC_NumOfUEsUpdate_Request message was sent in the registration procedure, the NSACF77 may determine whether the S-NSSAI(s) included in the Nnsacf_NSAC_NumOfUEsUpdate_Request message are associated with the attribute "UEs registered with 5GS" or the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0267] For example, NSACF 77 may determine whether S-NSSAI#2 is associated with the attribute "UEs registered with 5GS" or the attribute "maximum number of UEs with at least one PDU session / PDN connection." If NSACF 77 then determines that S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," it may not need to check the tally of the number of UEs registered for S-NSSAI#2.

[0268] For example, NSACF 77 may determine whether S-NSSAI#1 is associated with the attribute "UEs registered in 5GS" or the attribute "maximum number of UEs with at least one PDU session / PDN connection." If NSACF 77 determines that S-NSSAI#1 is associated with the attribute "UEs registered in 5GS," it may then check the tally of the number of UEs registered for S-NSSAI#1.

[0269] Step 7: The NSACF 77 uses the Nnsacf_NSAC_NumOfUEsUpdate_Response service operation to notify the AMF 70 whether the limit on the maximum number of registered UEs per network slice has been reached for the network slice(s) associated with the existing attribute, and sends an Unchecked NSSAI to the AMF 70, including the network slice(s) associated with the new attribute.

[0270] The Allowed NSSAI can include S-NSSAI#1. The Allowed NSSAI can also include S-NSSAI#2. The Allowed NSSAI can include at least one of S-NSSAI#1 and S-NSSAI#2. The Unchecked NSSAI can include S-NSSAI#2. The NSACF 77 can store the Unchecked NSSAI.

[0271] For example, if the maximum number of UEs registered to S-NSSAI#1 has not been reached, NSACF 77 may send an Nnsacf_NSAC_NumOfUesUpdate_Response message with an AllowedNSSAI that includes S-NSSAI#1.

[0272] For example, if the maximum number of UEs registered to S-NSSAI#1 has been reached, NSACF 77 can send an Nnsacf_NSAC_NumOfUesUpdate_Response message including a RejectedNSSAI that includes S-NSSAI#1.

[0273] For example, if the maximum number of UEs registered in S-NSSAI#1 has not been reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered in S-NSSAI#1 has not been reached.

[0274] For example, in addition to or instead of sending an Allowed NSSAI including S-NSSAI#1, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#1 has not been reached.

[0275] For example, if the maximum number of UEs registered to S-NSSAI#1 is reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#1 has been reached.

[0276] For example, in addition to or instead of sending a Rejected NSSAI including S-NSSAI#1, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered for S-NSSAI#1 has been reached.

[0277] For example, if NSACF77 does not confirm the tally of the number of UEs 3 registered for S-NSSAI#2 based on the new attribute "Maximum number of UEs with at least one PDU session / PDN connection" (or based on the determination described in step 6), NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including an Unchecked NSSAI that includes S-NSSAI#2.

[0278] For example, in addition to or instead of sending the Unchecked NSSAI, the NSACF 77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that verification of the count of the number of UEs 3 registered for S-NSSAI#2 has not been performed.

[0279] Step 8: Upon receiving the response from the NSACF 77, the AMF 70 sends a Registration Accept message to the UE 3, including at least one of an Allowed NSSAI, which indicates a set of S-NSSAIs that the UE 3 can use to access services from the serving PLMN in the current Registration Area, and a Rejected NSSAI, which indicates a set of S-NSSAIs that the UE 3 cannot use to access services. The Registration Accept message also includes an Unchecked NSSAI, which indicates a set of S-NSSAIs that are subject to NSAC and will be confirmed with the NSACF 77 during the PDU session establishment procedure before the UE 3 can use them to access services from the serving PLMN. The Unchecked NSSAI may not be included in the Registration Accept message.

[0280] The Unchecked NSSAIs include a set of S-NSSAIs with the attribute "maximum number of UEs with at least one PDU session / PDN connection", and their availability has not yet been confirmed with the NSACF 77 during the registration procedure if no PDU session has been established to the UE 3. The UE can use the S-NSSAI(s) specified in the Unchecked NSSAI while requesting PDU session establishment, but the availability of the S-NSSAI(s) is known only at the end of the PDU session establishment procedure after confirmation with the NSACF. The AMF 70 can store the Unchecked NSSAIs. When the UE 3 reselects a cell with a TAI that does not belong to the registered TAI and performs a mobility registration procedure, the old AMF includes the Unchecked NSSAIs in a message to the new AMF. The new AMF stores the Unchecked NSSAIs and updates the UE count during the PDU session establishment procedure for the S-NSSAIs stored in the Unchecked NSSAIs.

[0281] Here, the serving PLMN (e.g., AMF 70) sends the Allowed NSSAI (e.g., including S-NSSAI#1) and the Unchecked NSSAI (e.g., including S-NSSAI#2) to the UE 3 in a Registration Accept message. The Allowed NSSAI may include S-NSSAI#1. The Allowed NSSAI may also include S-NSSAI#2. The Allowed NSSAI may include at least one of S-NSSAI#1 and S-NSSAI#2. The Unchecked NSSAI may include S-NSSAI#2.

[0282] For example, if AMF 70 receives an Allowed NSSAI from NSACF 77, AMF 70 can send a Registration Accept message including the Allowed NSSAI.

[0283] For example, if AMF 70 receives a Rejected NSSAI from NSACF 77, AMF 70 can send a Registration Accept message including the Rejected NSSAI.

[0284] For example, if AMF 70 receives an Unchecked NSSAI from NSACF 77, AMF 70 can send a Registration Accept message including the Unchecked NSSAI.

[0285] For example, if AMF70 receives an Allowed NSSAI including S-NSSAI#1 from NSACF77, AMF70 can send a Registration Accept message having an Allowed NSSAI including S-NSSAI#1.

[0286] For example, if AMF70 receives a Rejected NSSAI including S-NSSAI#1 from NSACF77, AMF70 can send a Registration Accept message including a Rejected NSSAI including S-NSSAI#1.

[0287] For example, if AMF 70 receives an Unchecked NSSAI including S-NSSAI#2 from NSACF 77, AMF 70 can send a Registration Accept message including an Unchecked NSSAI including S-NSSAI#2.

[0288] For example, if AMF70 receives an Allowed NSSAI including S-NSSAI#1 and S-NSSAI#2, and an Unchecked NSSAI including S-NSSAI#2 from NSACF77, AMF70 can send a Registration Accept message having an Allowed NSSAI including S-NSSAI#1 and S-NSSAI#2, and an Unchecked NSSAI including S-NSSAI#2.

[0289] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#1 has not been reached, AMF70 can send a Registration Accept message having an Allowed NSSAI including S-NSSAI#1.

[0290] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#1 has been reached, AMF70 may send a Registration Accept message having a Rejected NSSAI including S-NSSAI#1.

[0291] For example, if AMF70 receives information from NSACF77 indicating that verification of the number of UEs 3 registered for S-NSSAI#2 has not been performed, AMF70 may send a Registration Accept message having an Unchecked NSSAI including S-NSSAI#2.

[0292] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered for S-NSSAI#1 has not been reached and that confirmation of the number of UEs registered for S-NSSAI#2 has not been performed, AMF70 can send a Registration Accept message having an Allowed NSSAI including S-NSSAI#1 and S-NSSAI#2, and an Unchecked NSSAI including S-NSSAI#2.

[0293] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered for S-NSSAI#1 has been reached and that confirmation of the number of UEs registered for S-NSSAI#2 has not been performed, AMF70 can send a Registration Accept message having a Rejected NSSAI including S-NSSAI#1, an Allowed NSSAI including S-NSSAI#2, and an Unchecked NSSAI including S-NSSAI#2.

[0294] For example, in addition to or instead of sending the Unchecked NSSAI, AMF70 may send a Registration Accept message including information indicating that verification of the count of the number of UE3s registered for S-NSSAI#2 has not been performed.

[0295] For example, if AMF70 receives information from NSACF77 indicating that confirmation of the number of UE3 registered for S-NSSAI#2 has not been performed, AMF70 may send a Registration Accept message including information indicating that confirmation of the number of UE3 registered for S-NSSAI#2 has not been performed.

[0296] (Modification 1 of the first embodiment related to the second aspect) In order to distinguish between the Nnsacf_NSAC_NumOfUEsUpdate_Request message from AMF70 and the Nnsacf_NSAC_NumOfUEsUpdate_Request message from SMF71, AMF70 can include information in the Nnsacf_NSAC_NumOfUEsUpdate_Request message indicating that the Nnsacf_NSAC_NumOfUEsUpdate_Request message was sent from AMF70.

[0297] If the NSACF 77 receives information from the AMF 70 indicating that a Nnsacf_NSAC_NumOfUEsUpdate_Request message has been sent and determines that the S-NSSAI#2 is associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection", the NSACF 77 does not need to check the tally of the number of UEs 3 registered for the S-NSSAI#2.

[0298] For example, instead of information indicating that the Nnsacf_NSAC_NumOfUEsUpdate_Request message was sent from AMF 70, information indicating that the Nnsacf_NSAC_NumOfUEsUpdate_Request message was sent during the registration procedure may be used.

[0299] (Second Example of the Second Aspect) This embodiment provides a mechanism for performing a procedure to verify and update the number of UEs available per S-NSSAI by configuring the NSACF to maintain a new attribute "maximum number of UEs with at least one PDU session / PDN connection" per network slice during the PDU session establishment procedure.

[0300] A detailed process of a second example embodiment relating to the second aspect will be described below with reference to Figure 4. Figure 4 shows a procedure for configuring an NSACF to recognize network slice(s) (S-NSSAI(s)) with a new attribute "maximum number of UEs with at least one PDU session / PDN connection" and applying NSAC during a PDU session establishment procedure. The process of the second example embodiment relating to the second aspect can be performed after the process of the first example embodiment relating to each aspect.

[0301] Step 1: The NSACF 77 is configured to recognize network slice(s) (S-NSSAI(s)) with a new attribute "Maximum number of UEs with at least one PDU session / PDN connection" configuration data for performing NSAC based on the slice type and its attributes. This step 1 may be the same as step 1 in Figure 3.

[0302] Step 2: UE3 provides S-NSSAI (e.g., S-NSSAI#2) and / or Unchecked NSSAI (e.g., including S-NSSAI#2) to SMF71 as part of a PDU session establishment request.

[0303] Step 2 can be separated into two parts:

[0304] The UE 3 may send a UL NAS Transport message including an S-NSSAI (e.g., S-NSSAI#2), a payload container, and / or an Unchecked NSSAI (e.g., including S-NSSAI#2) to the AMF 70. The payload container includes a PDU session establishment request message.

[0305] When AMF70 receives the UL NAS Transport message, AMF70 can send a PDU session establishment request message and / or an Nsmf_PDUSession_CreateSMContext Request message including an Unchecked NSSAI (e.g., including S-NSSAI#2) to SMF71.

[0306] In one embodiment, the PDU session establishment request message may include an Unchecked NSSAI (eg, including S-NSSAI#2).

[0307] Optionally, if the serving PLMN is not the home PLMN of the UE 3, the UE 3 may include an Allowed NSSAI / Unchecked NSSAI mapping, which maps each S-NSSAI of the Allowed NSSAI / Unchecked NSSAI to an S-NSSAI of the HPLMN.

[0308] The Unchecked NSSAI may not be included in the PDU session establishment request message. For example, in step 8 of Figure 3, if the UE 3 does not receive the Unchecked NSSAI from the AMF 70, the UE 3 may not send the Unchecked NSSAI.

[0309] For example, if UE 3 receives information indicating that the counting check of the number of registered UE 3s for S-NSSAI#2 has not been performed in step 8 of Figure 3, UE 3 may include this information in the PDU session establishment request message. This step 2 may be the same as step 2 of Figure 2.

[0310] Step 3: Steps 2 to 10b of the PDU session establishment procedure in TS23.502 (Non-Patent Document 3), Figure 4.3.2.2.1-1, are performed.

[0311] Step 4: SMF71 is configured with information indicating which network slices are subject to NSAC. Regardless of the attribute parameters, if the S-NSSAI(s) in the Allowed NSSAI and / or Unchecked NSSAI and / or in the PDU session establishment request message are subject to NSAC, SMF71 performs a verification and update procedure of the number of available UEs per network slice.

[0312] For example, when SMF71 receives an Unchecked NSSAI including S-NSSAI#2, SMF71 can perform a procedure to confirm and update the number of UEs available per network slice for S-NSSAI#2.

[0313] For example, if S-NSSAI#2 is the subject of NSAC and SMF71 receives a PDU session establishment request message having S-NSSAI#2 and / or an Unchecked NSSAI including S-NSSAI#2, SMF71 can perform a procedure to confirm and update the number of UEs available per network slice for S-NSSAI#2.

[0314] There may be multiple NSACFs 77 for different S-NSSAIs that are the subject of NSAC, and therefore the SMF 71 issues confirmation and update requests for the number of UEs available per network slice to multiple NSACFs 77.

[0315] Step 5: The SMF 71 uses the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation to share the UE ID, PDU Session ID, value of S-NSSAI(s) and Access Type information with the NSACF 77 to increase the number of UEs 3 registered to the same S-NSSAI(s).

[0316] For example, SMF 71 can send an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 to NSACF 77.

[0317] For example, SMF71 may send an Nnsacf_NSAC_NumOfUEsUpdate_Request message to NSACF77, which message includes at least one of S-NSSAI#1 and S-NSSAI#2.

[0318] For example, SMF71 may send an Nnsacf_NSAC_NumOfUEsUpdate_Request message to NSACF77 that includes an Unchecked NSSAI that includes S-NSSAI#2 (and / or information indicating that verification of the count of registered UEs for S-NSSAI#2 has not been performed).

[0319] For example, SMF71 may send an Nnsacf_NSAC_NumOfUEsUpdate_Request message to NSACF77, including at least one of S-NSSAI#1 and S-NSSAI#2, and an Unchecked NSSAI including S-NSSAI#2 (and / or information indicating that verification of the count of registered UEs for S-NSSAI#2 has not been performed).

[0320] Step 6: Using the available new attribute configuration data (e.g., attributes for each S-NSSAI), the NSACF 77 can identify (or determine) the network slice(s) associated with the new attribute "maximum number of UEs with at least one PDU session" and consider them for NSAC if they do not have a PDU session. The NSACF 77 checks the tally of the number of registered UEs per network slice associated with the new attribute, and if the total number does not exceed the maximum limit, increases the total number and allows UE 3 to use the same S-NSSAI. Step 6 can be triggered by receiving an Nnsacf_NSAC_NumOfUEsUpdate_Request message from the SMF 71.

[0321] For example, when NSACF77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 from SMF71, NSACF77 can determine whether S-NSSAI#2 is associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection."

[0322] For example, if NSACF77 determines that S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," it can check the tally of the number of UEs3 registered for S-NSSAI#2.

[0323] For example, if NSACF77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 from SMF71 and determines that S-NSSAI#2 is associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection," NSACF77 can check the count of the number of UEs3 registered for S-NSSAI#2.

[0324] For example, NSACF77 checks the tally of the number of UEs registered for S-NSSAI#2, and if the total number does not exceed the maximum limit, increases the total number and allows UE3 to use S-NSSAI#2.

[0325] For example, NSACF77 may check the tally of the number of UEs registered for S-NSSAI#2, and if the total number exceeds the maximum limit, may not increase the total number and may not allow UE3 to use S-NSSAI#2.

[0326] For example, when the NSACF 77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 from the SMF 71, the NSACF 77 can determine whether the S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection." If the NSACF 77 then determines that the S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," the NSACF 77 can check the tally of the number of UEs registered for the S-NSSAI#2. If the total number of UEs does not exceed the maximum limit, the NSACF 77 can increase the total number and cause the UEs to use the S-NSSAI#2; if the maximum limit is exceeded, the NSACF 77 can not increase the total number and cause the UEs to not use the S-NSSAI#2.

[0327] For example, when the NSACF 77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 and / or an Unchecked NSSAI including S-NSSAI#2 from the SMF 71, the NSACF 77 can determine whether S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection." If the NSACF 77 determines that S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," the NSACF 77 can check the tally of the number of UEs registered for S-NSSAI#2. If the total number of UEs does not exceed the maximum limit, the NSACF 77 can increase the total number and allow UEs to use S-NSSAI#2, and if the maximum limit is exceeded, the NSACF 77 can not increase the total number and prevent UEs from using S-NSSAI#2.

[0328] For example, if the NSACF 77 receives from the SMF 71 an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 and / or information indicating that a check of the number of UEs registered for S-NSSAI#2 has not been performed, the NSACF 77 may determine whether S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection." If the NSACF 77 determines that S-NSSAI#2 is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," it may check the tally of the number of UEs registered for S-NSSAI#2. If the total number of UEs does not exceed the maximum limit, the NSACF 77 may increase the total number and cause UE3 to use S-NSSAI#2, and if the maximum limit is exceeded, the NSACF 77 may not increase the total number and cause UE3 to not use S-NSSAI#2.

[0329] For example, if the NSACF 77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 and / or an Unchecked NSSAI including S-NSSAI#2 from the SMF 71, and if the S-NSSAI#2 and / or the Unchecked NSSAI in the Nnsacf_NSAC_NumOfUEsUpdate_Request message are associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," the NSACF 77 may check the tally of the number of UEs registered for S-NSSAI#2. The NSACF 77 may then increase the total number of UEs 3 if it does not exceed the maximum limit and allow the UEs 3 to use S-NSSAI#2, and may not increase the total number and prevent the UEs 3 from using S-NSSAI#2 if it does exceed the maximum limit.

[0330] For example, if the NSACF 77 receives from the SMF 71 an Nnsacf_NSAC_NumOfUEsUpdate_Request message including information indicating that checking the tally of the number of UEs registered for S-NSSAI#2 and / or S-NSSAI#2 has not been performed, and the S-NSSAI#2 in the Nnsacf_NSAC_NumOfUEsUpdate_Request message and / or the S-NSSAI#2 indicated by the information is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection," the NSACF 77 may check the tally of the number of UEs registered for S-NSSAI#2. The NSACF 77 may then increase the total number of UEs 3 if the total number does not exceed the maximum limit and allow UE 3 to use S-NSSAI#2, or may not increase the total number and prevent UE 3 from using S-NSSAI#2 if the maximum limit is exceeded. This step 6 may be the same as step 6a of FIG. 2.

[0331] Step 7: The NSACF 77 uses the Nnsacf_NSAC_NumOfUEsUpdate_Response service operation to notify the SMF 71 whether the limit on the maximum number of registered UEs per network slice has been reached.

[0332] For example, if the maximum number of UEs registered to S-NSSAI#2 has not been reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#2 has not been reached.

[0333] For example, if the maximum number of UEs registered to S-NSSAI#2 is reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#2 has been reached.

[0334] Since the network slice(s) associated with the existing attribute have already been tallied during the registration procedure, the NSACF 77 sends them to the SMF 71 for processing directly without applying NSAC to them again.

[0335] 3, if the number of UEs 3 for S-NSSAI#1 has already been counted and NSACF 77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#1, NSACF 77 may not count the number of UEs 3 for S-NSSAI#1 and may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message to SMF 71 including information indicating that the maximum number of UEs registered in S-NSSAI#1 has not been reached. Instead of the information indicating that the maximum number of UEs registered in S-NSSAI#1 has not been reached, information indicating that the number of UEs 3 for S-NSSAI#1 has already been counted may be used.

[0336] Step 8: Upon receiving the response from the NSACF 77, the SMF 71 sends either a PDU Session Establishment Accept message by including an S-NSSAI from the Allowed NSSAI / Unchecked NSSAI received in step 3, or a PDU Session Establishment Reject message with the reason "maximum number of UEs with at least one PDU session per S-NSSAI reached" to the AMF 70. This step 8 may be the same as step 8a in Figure 2.

[0337] Step 9: The AMF 70 transmits the message received from the SMF 71 to the UE 3. Here, the AMF 70 transmits a PDU Session Establishment Reject message including a Rejected S-NSSAI (e.g., S-NSSAI#2) with the reason "the maximum number of UEs with at least one PDU session per S-NSSAI has been reached" and, optionally, a back-off timer. The AMF 70 can transmit the PDU Session Establishment Reject message including the back-off timer (or back-off timer value) to the UE 3. This step 9 may be the same as step 9a in Figure 2.

[0338] Step 10: When UE3 receives the PDU Session Establishment Accept message in step 9, UE3 deletes S-NSSAI#2 from the Unchecked NSSAI list (or Unchecked NSSAI). When UE3 receives the PDU Session Establishment Reject message in step 9, UE3 may start a timer with a value set for the back-off timer, and UE3 will not initiate the PDU session establishment procedure for S-NSSAI#2 until the timer expires. This step 10 may be performed after step 9a in FIG. 2. In this case, AMF70 may transmit the back-off timer (or back-off timer value) to UE3 in step 9a. For example, the transmission of the back-off timer by UE3 and corresponding process(es) may be applied to other aspects.

[0339] (Modification 1 of the second embodiment related to the second aspect) Similar to variant 4 of the second embodiment relating to the first aspect, during the procedure of FIG. 4, SMF 71 may perform a procedure for checking and updating the number of UEs available per network slice.

[0340] (Modification 2 of the second embodiment related to the second aspect) Instead of using the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation, the SMF 71 can use the Nnsacf_NSAC_NumOfPDUsUpdate_Request service operation. For example, in step 5, the SMF 71 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Request message with S-NSSAI#2 and / or an Unchecked NSSAI that includes S-NSSAI#2.

[0341] For example, if the NSACF 77 stores an Unchecked NSSAI that includes S-NSSAI#2 (e.g., the NSACF 77 sent an Unchecked NSSAI in step 8 of FIG. 3 and stored the sent Unchecked NSSAI that includes S-NSSAI#2), and the NSACF 77 receives an Nnsacf_NSAC_NumOfPDUsUpdate_Request message that includes S-NSSAI#2 (and / or an Unchecked NSSAI that includes S-NSSAI#2), the NSACF 77 can determine whether the S-NSSAI#2 is associated with the attribute "maximum number of UEs that have at least one PDU session / PDN connection." If the NSACF 77 determines that the S-NSSAI#2 is associated with the attribute "maximum number of UEs that have at least one PDU session / PDN connection," the NSACF 77 can perform the process(es) of step 6.

[0342] Furthermore, when NSACF77 receives an Nnsacf_NSAC_NumOfPDUsUpdate_Request message including S-NSSAI#2, it can perform a procedure to check and update the number of PDU sessions available per network slice.

[0343] For example, NSACF 77 may check the tally of the number of UEs 3 registered for S-NSSAI#2, and if the total number does not exceed the maximum limit, may increase the total number and allow UEs 3 to use S-NSSAI#2. NSACF 77 may then check the tally of the number of PDU sessions established for S-NSSAI#2.

[0344] For example, based on the results of checking the tally of the number of registered UEs 3 and the tally of the number of PDU sessions established for S-NSSAI(s), NSACF 77 can include in the Nnsacf_NSAC_NumOfPDUsUpdate_Response message information indicating whether the maximum number of UEs registered for S-NSSAI#2 has been reached, and information indicating whether the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0345] For example, if the maximum number of UEs registered for S-NSSAI#2 has not been reached and the maximum number of PDU sessions established for S-NSSAI#2 has not been reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71, the message including at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has not been reached.

[0346] For example, if the maximum number of UEs registered for S-NSSAI#2 has been reached and the maximum number of PDU sessions established for S-NSSAI#2 has been reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71, the message including at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0347] For example, if the maximum number of UEs registered for S-NSSAI#2 has been reached and the maximum number of PDU sessions established for S-NSSAI#2 has not been reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71, the message including at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has not been reached.

[0348] For example, if the maximum number of UEs registered for S-NSSAI#2 has not been reached and the maximum number of PDU sessions established for S-NSSAI#2 has been reached, NSACF77 can send an Nnsacf_NSAC_NumOfPDUsUpdate_Response message to SMF71 that includes at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0349] For example, if the response from NSF77 contains information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has not been reached, SMF71 can send a PDU Session Establishment Accept message including S-NSSAI#2.

[0350] For example, SMF71 may send a PDU Session Establishment Reject message including S-NSSAI#2 if the response from NSACF77 includes at least one of information indicating that the maximum number of UEs registered for S-NSSAI#2 has been reached and information indicating that the maximum number of PDU sessions established for S-NSSAI#2 has been reached.

[0351] (Modification 3 of the second embodiment related to the second aspect) Modification 5 of the second embodiment relating to the first aspect may be applied to the second aspect.

[0352] (Modification 4 of the second embodiment related to the second aspect) Modification 6 of the second embodiment relating to the first aspect may be applied to the second aspect.

[0353] For example, if NSACF77 receives information indicating that a Nnsacf_NSAC_NumOfUEsUpdate_Request message has been sent from SMF71 and determines that S-NSSAI#2 is associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection," NSACF77 can check the tally of the number of UEs3 registered for S-NSSAI#2.

[0354] (Third aspect) This aspect provides a mechanism for supporting the new GSMA-defined attribute "maximum number of UEs with at least one PDU session / PDN connection" for each network slice by configuring the NSACF to internally recognize the network slice(s) with their attribute details in order to monitor and limit the total number of UEs in a unified manner.

[0355] For example, this aspect provides a mechanism to accommodate the new GSMA-defined attribute "maximum number of UEs with at least one PDU session / PDN connection" per network slice that can be used simultaneously by the maximum number of UEs (both 5GS and EPS UEs) by configuring the NSACF to internally recognize network slice(s) with attribute details in order to monitor and limit the total number of UEs in a unified manner.

[0356] (First Example of the Third Aspect) This embodiment provides a mechanism in which the NSACF is internally configured to recognize details of the network slice(s) and their attributes, and performs a verification and update procedure of the number of UEs available per S-NSSAI within the NSACF during the registration procedure.

[0357] A detailed process of the first embodiment relating to the third aspect will be described below with reference to Figure 5. Figure 5 shows a procedure for internally configuring the NSACF to recognize network slice(s) (S-NSSAI(s)) using attribute configuration data and applying the NSAC during the registration procedure.

[0358] Step 1: The NSACF 77 is internally configured to recognize network slice(s) (S-NSSAI(s)) having attribute parameter configuration data for performing NSAC based on the slice type and its attributes. This step 1 may be the same as step 1 in Figure 3.

[0359] For network slice(s) whose attribute is "maximum number of UEs with at least one PDU session / PDN connection", UEs 3 that are registered with the 5GS network slice but do not have a PDU session established are not counted. Also, the new attribute "maximum number of UEs with at least one PDU session / PDN connection" is not used together with the attribute "maximum number of UEs".

[0360] Step 2: NSSAI is a collection of S-NSSAIs. Requested NSSAI is an NSSAI provided by UE3 to the serving PLMN during the registration procedure. Here, UE3 provides the Requested NSSAI to AMF70 as part of the Registration Request, and the Requested NSSAI includes two S-NSSAIs (S-NSSAI#1 and S-NSSAI#2). This step 2 may be the same as step 2 in Figure 1.

[0361] Optionally, if the serving PLMN is not the home PLMN of the UE 3, the UE 3 may include a mapping of Requested NSSAIs, which maps each S-NSSAI of the Requested NSSAI to an S-NSSAI of the HPLMN.

[0362] Step 3: Steps 2 to 19c of the registration procedure in TS23.502 (Non-Patent Document 3) and FIG. 4.2.2.2.2-1 are performed.

[0363] Step 4: The AMF 70 is configured with information indicating which network slices are subject to NSAC. If the S-NSSAI(s) in the Requested NSSAI are subject to NSAC regardless of their attribute parameters, the AMF 70 performs a verification and update procedure of the number of available UEs per network slice. This step 4 may be the same as step 4 in Figure 3.

[0364] There may be multiple NSACFs 77 for different S-NSSAIs that are the subject of NSAC, and therefore the AMF 70 performs the verification and update procedure for the number of UEs 3 available per network slice for multiple NSACFs 77.

[0365] Step 5: The AMF 70 uses the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation to share the UE ID, value of S-NSSAI(s) and Access Type information with the NSACF 77 and increase the number of UEs 3 registered to the same S-NSSAI(s). This step 5 may be the same as step 5 in FIG.

[0366] Step 6: Using the available attribute parameter configuration data, NSACF77 can identify network slice(s) and group them based on attribute parameters such as network slices associated with i) the new attribute "Maximum number of UEs with at least one PDU session / PDN connection" and ii) the existing attribute "UEs registered with 5GS".

[0367] The network slice(s) associated with the existing attribute "UE registered in 5GS" are considered for NSAC at this stage. NSACF77 checks the tally of the number of registered UE3s for each network slice associated with the existing attribute, and if the total number does not exceed the maximum limit, increases the total number and allows UE3s to use the same S-NSSAI.

[0368] For network slice(s) associated with the new attribute "Maximum number of UEs with at least one PDU session / PDN connection" during the registration procedure, NSACF 77 may not perform any action on the network slice(s) and may simply passively include the network slice(s) in the Allowed NSSAI. This step 6 may be the same as step 6 in Figure 3.

[0369] Step 7: The NSACF 77 uses the Nnsacf_NSAC_NumOfUEsUpdate_Response service operation to notify the AMF 70 whether the limit on the maximum number of registered UEs per network slice has been reached for the network slice(s) associated with the existing attribute.

[0370] This step 7 may be the same as step 7 in Figure 3. Alternatively, this step 7 may be the same as step 7 in Figure 3, except for sending an Unchecked NSSAI.

[0371] For example, if the maximum number of UEs registered to S-NSSAI#1 has not been reached, NSACF 77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message with an Allowed NSSAI that includes S-NSSAI#1.

[0372] For example, if the maximum number of UEs registered to S-NSSAI#1 has been reached, NSACF 77 can send an Nnsacf_NSAC_NumOfUesUpdate_Response message including a RejectedNSSAI that includes S-NSSAI#1.

[0373] For example, if the maximum number of UEs registered in S-NSSAI#1 has not been reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered in S-NSSAI#1 has not been reached.

[0374] For example, in addition to or instead of sending an Allowed NSSAI including S-NSSAI#1, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#1 has not been reached.

[0375] For example, if the maximum number of UEs registered to S-NSSAI#1 is reached, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered to S-NSSAI#1 has been reached.

[0376] For example, in addition to or instead of sending a Rejected NSSAI including S-NSSAI#1, NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered for S-NSSAI#1 has been reached.

[0377] For example, if NSACF77 does not confirm the counting of the number of UEs registered for S-NSSAI#2 based on the new attribute "Maximum number of UEs with at least one PDU session / PDN connection" (e.g., even if NSACF77 does not perform the counting of the number of UEs registered for S-NSSAI#2), NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message with an Allowed NSSAI including S-NSSAI#2.

[0378] For example, if NSACF77 does not confirm the counting of the number of UEs registered for S-NSSAI#2 based on the new attribute "Maximum number of UEs with at least one PDU session / PDN connection" in addition to or instead of sending an AllowedNSSAI including S-NSSAI#2 (e.g., even if NSACF77 does not perform the counting of the number of UEs registered for S-NSSAI#2), NSACF77 may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message including information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached.

[0379] In the present disclosure, information indicating that the maximum number of UEs registered in S-NSSAI#2 has not been reached can be expressed as information indicating that counting of the number of UEs3 has not been performed for S-NSSAI#2, or information indicating that NSAC regarding the number of UEs3 for S-NSSAI#2 has not been performed.

[0380] The Allowed NSSAI may include S-NSSAI#1. The Allowed NSSAI may also include S-NSSAI#2. The Allowed NSSAI may include at least one of S-NSSAI#1 and S-NSSAI#2.

[0381] Step 8: Upon receiving the response from the NSACF 77, the AMF 70 sends at least one of an Allowed NSSAI, which indicates a set of S-NSSAIs that the UE 3 can use to access services from serving PLMNs in the current Registration Area, and a Rejected dNSSAI, which indicates a set of S-NSSAIs that the UE 3 cannot use to access services. Here, the AMF 70 of the serving PLMN sends the Allowed NSSAIs to the UE 3 in a Registration Accept message (e.g., including S-NSSAI#1, S-NSSAI#2).

[0382] This step 8 may be the same as step 8 in Figure 3. Alternatively, this step 8 may be the same as step 8 in Figure 3, except for sending an Unchecked NSSAI.

[0383] For example, if AMF 70 receives an Allowed NSSAI from NSACF 77, AMF 70 can send a Registration Accept message including the Allowed NSSAI.

[0384] For example, if AMF 70 receives a Rejected NSSAI from NSACF 77, AMF 70 can send a Registration Accept message including the Rejected NSSAI.

[0385] For example, if AMF70 receives an Allowed NSSAI from NSACF77 that includes at least one of S-NSSAI#1 and S-NSSAI#2, AMF70 can send a Registration Accept message having an Allowed NSSAI that includes at least one of S-NSSAI#1 and S-NSSAI#2.

[0386] For example, if AMF70 receives a Rejected NSSAI including S-NSSAI#1 from NSACF77, AMF70 can send a Registration Accept message including a Rejected NSSAI including S-NSSAI#1.

[0387] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#1 has not been reached, AMF70 can send a Registration Accept message having an Allowed NSSAI including S-NSSAI#1.

[0388] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered to S-NSSAI#1 has been reached, AMF70 may send a Registration Accept message having a Rejected NSSAI including S-NSSAI#1.

[0389] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered for S-NSSAI#1 has not been reached and information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached, AMF70 can send a Registration Accept message having an Allowed NSSAI that includes at least one of S-NSSAI#1 and S-NSSAI#2.

[0390] For example, if AMF70 receives information from NSACF77 indicating that the maximum number of UEs registered for S-NSSAI#1 has been reached and information indicating that the maximum number of UEs registered for S-NSSAI#2 has not been reached, AMF70 can send a Registration Accept message having a Rejected NSSAI including S-NSSAI#1 and an Allowed NSSAI including S-NSSAI#2.

[0391] (Modification 1 of the first embodiment related to the third aspect) The third aspect may be applied to the first modification of the first embodiment relating to the second aspect.

[0392] (Second Example of the Third Aspect) This embodiment provides a mechanism for the NSACF to be internally configured to recognize details of the network slice and its attributes in order to perform a procedure for checking and updating the number of UEs available per S-NSSAI in the NSACF during the PDU session establishment procedure.

[0393] A detailed process of a second embodiment relating to the third aspect will be described below with reference to Figure 6. Figure 6 shows a procedure for internally configuring an NSACF to recognize network slice(s) (S-NSSAI(s)) using attribute parameters and applying NSAC during a PDU session establishment procedure. The process of the second embodiment relating to the third aspect can be performed after the process of the embodiment relating to the first aspect.

[0394] Step 1: The NSACF 77 is internally configured to recognize the network slice(s) using its attribute parameter configuration data for performing NSAC based on the slice type and its attributes. This step 1 may be the same as step 1 in Figure 5.

[0395] Step 2: UE3 provides S-NSSAI (e.g., S-NSSAI#2) to SMF71 as part of the PDU session establishment request.

[0396] Step 2 can be separated into two parts:

[0397] The UE 3 may send a UL NAS Transport message including an S-NSSAI (e.g., S-NSSAI#2), a payload container, and / or an Unchecked NSSAI (e.g., S-NSSAI#2) to the AMF 70. The payload container includes a PDU session establishment request message. The UL NAS Transport message may include an Unchecked NSSAI (e.g., including S-NSSAI#2).

[0398] When the AMF 70 receives the UL NAS Transport message, the AMF 70 can send an Nsmf_PDUSession_CreateSMContext Request message, which includes a PDU session establishment request message, to the SMF 71. The Nsmf_PDUSession_CreateSMContext Request message can include an Unchecked NSSAI (e.g., including S-NSSAI#2).

[0399] In one embodiment, the PDU session establishment request message may include an Unchecked NSSAI (eg, including S-NSSAI#2).

[0400] For example, if UE3 has an Unchecked NSSAI (e.g., including S-NSSAI#2), UE3 can send a UL NAS Transport message including the Unchecked NSSAI to AMF70. For example, in step 8a of Figure 1 or step 8 of Figure 3, if UE3 receives a Registration Accept message including an Unchecked NSSAI (e.g., including S-NSSAI#2) and UE3 has an Unchecked NSSAI, UE3 can send a UL NAS Transport message including the Unchecked NSSAI.

[0401] Optionally, if the serving PLMN is not the home PLMN of the UE 3, the UE 3 may include an Allowed NSSAI / Unchecked NSSAI mapping, which maps each S-NSSAI of the Allowed NSSAI / Unchecked NSSAI to an HPLMNS-NSSAI.

[0402] Step 3: Steps 2 to 10b of the PDU session establishment procedure in TS23.502 (Non-Patent Document 3), Figure 4.3.2.2.1-1, are performed.

[0403] Step 4: SMF 71 is configured with information indicating which network slices are subject to NSAC. Regardless of the attribute parameter, if S-NSSAI(s) in the Allowed NSSAI are subject to NSAC, SMF 71 performs the verification and update procedure of the number of available UEs per network slice.

[0404] There may be multiple NSACFs 77 for different S-NSSAIs that are the subject of NSAC, and therefore the SMF 71 performs the confirmation and update procedure of the number of UEs 3 available per network slice for multiple NSACFs 77. This step 4 may be the same as step 4 in Figure 4.

[0405] Step 5: The SMF 71 uses the Nnsacf_NSAC_NumOfUEsUpdate_Request service operation to share the UE ID, PDU Session ID, value of S-NSSAI(s) and Access Type information with the NSACF 77 and increment the number of UEs 3 registered to the same S-NSSAI(s).

[0406] For example, SMF 71 can send an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#2 to NSACF 77.

[0407] For example, SMF71 may send an Nnsacf_NSAC_NumOfUEsUpdate_Request message to NSACF77, which message includes at least one of S-NSSAI#1 and S-NSSAI#2.

[0408] For example, the SMF 71 can send an Nnsacf_NSAC_NumOfUEsUpdate_Request message including an Unchecked NSSAI that includes S-NSSAI#2 to the NSACF 77. This step 5 may be the same as step 5 in FIG.

[0409] Step 6: Using the available new attribute configuration data (e.g., attributes for each S-NSSAI(s)), the NSACF 77 identifies the network slices associated with the new attribute "maximum number of UEs with at least one PDU session / PDN connection" and can consider them for NSAC if they do not have a PDU session. The NSACF 77 checks the tally of the number of registered UEs 3 for each network slice associated with the new attribute, and if the total number does not exceed the maximum limit, increases the total number and allows the UEs 3 to use the same S-NSSAI. This step 6 can be triggered by receiving an Nnsacf_NSAC_NumOfUEsUpdate_Request message from the SMF 71. This step 6 may be the same as step 6 in Figure 4.

[0410] Step 7: The NSACF 77 uses the Nnsacf_NSAC_NumOfUEsUpdate_Response service operation to notify the SMF 71 whether the limit on the maximum number of registered UEs 3 per network slice has been reached. This step 7 may be the same as step 7 in Figure 4.

[0411] Since the network slice(s) associated with the existing attributes have already been tallied during the registration procedure, the NSACF 77 can send them to the SMF 71 for processing directly without applying NSAC again.

[0412] For example, in step 6 of Figure 3, if the number of UEs 3 for S-NSSAI#1 has already been counted and NSACF77 receives an Nnsacf_NSAC_NumOfUEsUpdate_Request message including S-NSSAI#1, NSACF77 may not count the number of UEs 3 for S-NSSAI#1 and may send an Nnsacf_NSAC_NumOfUEsUpdate_Response message to SMF71 including information indicating that the maximum number of UEs registered to S-NSSAI#1 has not been reached.

[0413] Step 8: Upon receiving the response from the NSACF 77, the SMF 71 sends either a PDU Session Establishment Accept message by including the S-NSSAI from the Allowed NSSAI received in step 3, or a PDU Session Establishment Reject message with the reason "maximum number of UEs with at least one PDU session per S-NSSAI reached" to the AMF 70. This step 8 may be the same as step 8 in Figure 4.

[0414] Step 9: The AMF 70 sends the message received from the SMF 71 to the UE 3. Here, the AMF 70 sends a PDU Session Establishment Reject message with the reason "The maximum number of UEs with at least one PDU session per S-NSSAI has been reached." This step 9 may be the same as step 9 in Figure 4.

[0415] The AMF 70 may send a PDU Session Establishment Reject message including the back-off timer (or back-off timer value) to the UE 3. If the UE 3 receives the back-off timer, it may perform process(es) similar to step 10 of FIG.

[0416] (Modification 1 of the second embodiment related to the third aspect) As with variant 4 of the second embodiment relating to the first aspect, during the procedure of Figure 6, SMF71 can perform a procedure to confirm and update the number of PDU sessions available per network slice.

[0417] (Modification 2 of the second embodiment related to the third aspect) Modification 2 of the second embodiment relating to the second aspect may be applied to the third aspect.

[0418] (Modification 3 of the second embodiment related to the third aspect) Modification 5 of the second embodiment relating to the first aspect may be applied to the third aspect.

[0419] (Modification 4 of the second embodiment related to the third aspect) Modification 6 of the second embodiment relating to the first aspect may be applied to the third aspect.

[0420] For example, if NSACF77 receives information indicating that a Nnsacf_NSAC_NumOfUEsUpdate_Request message has been sent from SMF71 and determines that S-NSSAI#2 is associated with the attribute "Maximum number of UEs with at least one PDU session / PDN connection," NSACF77 can check the tally of the number of UEs3 registered for S-NSSAI#2.

[0421] (Aspect 4) This aspect provides a mechanism for configuring the Early Admission Control (EAC) update procedure to enable EAC mode for S-NSSAIs that are subject to NSAC and have the attribute "maximum number of UEs with at least one PDU session / PDN connection."

[0422] The detailed process of the fourth aspect is described below with reference to Figure 7. Figure 7 shows the Early Admission Control (EAC) update procedure for S-NSSAI with NSAC target attribute "Maximum number of UEs with at least one PDU session / PDN connection".

[0423] Step 1: The NSACF 77 is configured to recognize network slice(s) (S-NSSAI(s)) with a new attribute "Maximum number of UEs with at least one PDU session / PDN connection" configuration data for performing NSAC based on the slice type and its attributes. This step 1 may be the same as step 1 in Figure 3.

[0424] AMF70 may authorize EAC notification.

[0425] For example, if AMF70 performs a procedure to check and update the number of UEs available per network slice in NSACF77, AMF70 can authorize EAC notification of S-NSSAI.

[0426] For example, AMF 70 implicitly authorizes EAC notification of S-NSSAI when NSACF 77 performs the procedure of checking and updating the number of UEs available per network slice for S-NSSAI.

[0427] (About AMF) Step 2a: The NSACF 77 sends an EAC mode notification to the AMF 70 together with the attribute parameters to which the authorized S-NSSAI is associated.

[0428] For example, the NSACF 77 may send an EAC mode notification (e.g., an Nnsacf_NSAC_EACNotify message) to the AMF 70, including information indicating that the S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection." The EAC mode notification may include information indicating that the S-NSSAI#1 has or is associated with the attribute "UE registered with 5GS."

[0429] In the present disclosure, the attribute parameter may include at least one of information indicating that S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" and information indicating that S-NSSAI#1 has or is associated with the attribute "UEs registered in 5GS".

[0430] Step 3a: AMF70 uses the attribute parameter information of the notified S-NSSAI to perform the verification and update procedure of the number of UEs available per S-NSSAI if the S-NSSAI is subject to NSAC and is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" as proposed in the first embodiment relating to the first aspect of Figure 1.

[0431] (About SMF) Step 2b: The NSACF 77 sends an EAC mode notification to the SMF 71 along with the attribute parameters with which the authorized S-NSSAI is associated. For example, the NSACF 77 can send an EAC mode notification (e.g., an Nnsacf_NSAC_EACNotify message) to the SMF 71 including information indicating that the S-NSSAI#2 has or is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection." The EAC mode notification can include information indicating that the S-NSSAI#1 has or is associated with the attribute "UE registered with 5GS."

[0432] Step 3b: SMF71 uses the attribute parameter information of the notified S-NSSAI to perform the verification and update procedure of the number of UEs available per S-NSSAI if the S-NSSAI is subject to NSAC and is associated with the attribute "maximum number of UEs with at least one PDU session / PDN connection" as proposed in the second example embodiment for the first aspect of Figure 2.

[0433] According to the above-described embodiments relating to each aspect and their modifications, at least the above-mentioned problems can be solved.

[0434] For example, the above-described embodiments of each aspect and their variations provide at least one of an apparatus and a method that can solve at least the above-mentioned problems. For example, the above embodiments relating to each aspect and their variations can solve the problem that there is no mechanism for addressing at least one of the new attributes and requirements in the current 3GPP specifications.

[0435] (System Overview) FIG. 8 illustrates schematically a telecommunications system 1 for mobile (cellular or wireless) devices (known as user equipment (UE)) to which the above aspects can be applied.

[0436] The telecommunications system 1 is an overview of a system capable of end-to-end communication, for example, a UE 3 (or user equipment, "mobile device" 3) communicating with other UEs 3 or service servers in a data network 20 via corresponding (R)AN nodes 5 and a core network 7.

[0437] The (R)AN node 5 supports any wireless access technology, including non-3GPP RATs, including, for example, 5G radio access technology (RAT), E-UTRA radio access technology, Beyond 5G RAT, 6G RAT, and wireless local area network (WLAN) technology defined by the Institute of Electrical and Electronics Engineers (IEEE).

[0438] The (R)AN node 5 can be divided into a Radio Unit (RU), a Distributed Unit (DU), and a Centralized Unit (CU). In an aspect, each of the units can be connected to each other to construct the (R)AN node 5 by adopting an architecture defined by the Open RAN (O-RAN) Alliance, where the above units are referred to as the O-RU, O-DU, and O-CU, respectively.

[0439] The (R)AN node 5 may be divided into one or more control plane functions and one or more user plane functions. Furthermore, multiple user plane functions may be allocated to accommodate communications. In some aspects, user traffic may be distributed across multiple user plane functions, with user traffic on each user plane function being aggregated to both the UE 3 and the (R)AN node 5. This divided architecture may be referred to as "dual connectivity" or "multi-connectivity."

[0440] The (R)AN node 5 may also support communications using satellite access. In an aspect, the (R)AN node 5 may support satellite access and terrestrial access.

[0441] The (R)AN node 5 may also be referred to as an access node for non-wireless access, including fixed line access as defined by the Broadband Forum (BBF) and optical access as defined by the Innovative Optical and Wireless Network (IOWN).

[0442] The core network 7 may include logical nodes (or "functions") for supporting communications in the telecommunications system 1. For example, the core network 7 may be a 5G Core Network (5GC), which includes control plane functions and user plane functions, among other functions. Each function within a logical node may be considered a network function. Network functions may be provided to other nodes by adapting a Service Based Architecture (SBA).

[0443] By adapting network virtualization techniques as defined by the European Telecommunications Standards Institute Network Functions Virtualization (ETSI NFV), network functions can be deployed as distributed, redundant, stateless, and scalable, providing services from several locations and several running instances at each location.

[0444] The core network 7 can correspond to a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN). As is known, as a UE 3 moves within the geographic area covered by the telecommunications system 1, the UE 3 may move in and out of areas (i.e., radio cells) served by the (R)AN nodes 5. To track the UE 3 and facilitate movement between different (R)AN nodes 5, the core network 7 comprises at least one Access and Mobility Management Function (AMF) 70. The AMF 70 communicates with the (R)AN nodes 5 coupled to the core network 7. In some core networks, a Mobility Management Entity (MME) or mobility management node for Beyond 5G may be used instead of the AMF 70, or a mobility management node for 6G may be used.

[0445] The core network 7 also includes, among other things, a Session Management Function (SMF) 71, a User Plane Function (UPF) 72, a Policy Control Function (PCF) 73, a Network Exposure Function (NEF) 74, a Unified Data Management (UDM) 75, a Network Slice Selection Function (NSSF) 76, and a Network Slice Admission Control Function (NSACF) 77. When a UE 3 is roaming in a Visited Public Land Mobile Network (VPLMN), the Home Public Land Mobile Network (HPLMN) of the UE 3 provides at least some of the functionality of the UDM 75, SMF 71, UPF 72, and PCF 73 to the roaming-out UE 3.

[0446] The UE 3 and each serving (R)AN node 5 are connected via an appropriate air interface (e.g., the so-called "Uu" interface, etc.). Adjacent (R)AN nodes 5 are connected to each other via appropriate (R)AN node 5 (e.g., the so-called "Xn" interface) to (R)AN node interfaces. Each (R)AN node 5 is also connected to nodes within the core network 7 (e.g., so-called core network nodes) via appropriate interfaces (e.g., the so-called "N2" / "N3" interface(s)). The core network 7 also provides a connection to a data network 20. The data network 20 can be the Internet, a public network, an external network, a private network, or an internal network of a PLMN. If the data network 20 is provided by a PLMN operator or a Mobile Virtual Network Operator (MVNO), the data network 20 can provide IP Multimedia Subsystem (IMS) services. The UE 3 can connect to the data network 20 using IPv4, IPv6, IPv4v6, Ethernet, or unstructured data types.

[0447] The "Uu" interface may include a control plane and a user plane.

[0448] The user plane of the Uu interface is responsible for carrying user traffic between the UE 3 and the serving (R)AN node 5. The user plane of the Uu interface may have a layered structure, with SDAP, PDCP, RLC, and MAC sublayers over the physical connection.

[0449] The control plane of the Uu interface is responsible for establishing, modifying, and releasing the connection between the UE 3 and the serving (R)AN node 5. The control plane of the Uu interface may have a hierarchical structure, with RRC, PDCP, RLC, and MAC sublayers over the physical connection.

[0450] For example, the following messages are communicated over the RRC layer to accommodate AS signaling: RRC Setup Request message: This message is sent from the UE 3 to the (R)AN node 5. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be included together in the RRC Setup Request message: #establishmentCause, and ue-Identity, where ue-Identity can have the value of ng-5G-S-TMSI-Part1 or randomValue. RRC Setup message: This message is sent from the (R)AN node 5 to the UE 3. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be included together in the RRC Setup message: #masterCellGroup, and radioBearerConfig. RRC Setup Complete message: This message is sent from the UE 3 to the (R)AN node 5. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be included together in the RRC Setup Complete message: #guami-Type, iab-NodeIndication, idleMeasAvailable, mobilityState, ng-5G-S-TMSI-Part2, registeredAMF, selectedPLMN-Identity

[0451] The UE 3 and the AMF 70 are connected via an appropriate interface (such as the so-called N1 interface). The N1 interface is responsible for providing communication between the UE 3 and the AMF 70 to support NAS signaling. The N1 interface can be established via 3GPP access and non-3GPP access. For example, the following messages are communicated via the N1 interface: Registration Request message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be included together in the Registration Request message: #5GS registration type, ngKSI, 5GS mobile identity, Non-current native NAS key set identifier, 5GMM capability, UE security capability, Requested NSSAI, Last visited registered TAI, S1 UE network capability, Uplink data status, PDU session status, MICO indication, UE status, Additional GUTI, Allowed PDU session status, UE's usage setting, Requested DRX parameters, EPS NAS message container, LADN indication, Payload container type, Payload container, Network slicing indication, 5GS update type, Mobile station classmark 2, Supported codecs, NAS message container, EPS bearer context status, Requested extended DRX parameters, T3324 value, UE radio capability ID, Requested mapped NSSAI, Additional information requested, Requested WUS assistance information, N5GC indication, and Requested NB-N1 mode DRX parameters. Registration Accept message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be included together in the Registration Accept message: #5GS registration result, 5G-GUTI, Equivalent PLMNs, TAI list, Allowed NSSAI, Rejected NSSAI, Configured NSSAI, 5GS network feature support, PDU session status, PDU session reactivation result, PDU session reactivation result error cause, LADN information, MICO indication, Network slicing indication, Service area list, T3512 value, Non-3GPP de-registration timer value, T3502 value, Emergency number list, Extended emergency number list, SOR transparent container, EAP message, NSSAI inclusion mode, Operator-defined access category definitions, Negotiated DRX parameters, Non-3GPP NW policies, EPS bearer context status, Negotiated extended DRX parameters, T3447 value, T3448 value, T3324 value, UE radio capability ID, UE radio capability ID deletion indication, Pending NSSAI, Ciphering key data, CAG information list, Truncated �G-S-TMSI configuration, Negotiated WUS assistance information, Negotiated NB-N1 mode DRX parameters, and Extended rejected NSSAI. Registration Complete message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters disclosed by the embodiments of the present disclosure, the following parameters may be included together in the Registration Complete message: #SOR transparent container. Authentication Request message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be included together in the Authentication Request message: #ngKSI, ABBA, Authentication parameter RAND(5G authentication challenge), Authentication parameter AUTN(5G authentication challenge), and EAP message. Authentication Response message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be taken together in the Authentication Response message: #Authentication response message identity,Authentication response parameter and EAP message. Authentication Result message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be taken together in the Authentication Result message: #ngKSI, EAP Message, and ABBA. Authentication Failure message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be taken together in the Authentication Failure message: #Authentication failure message identification, 5GMM cause, and authentication failure parameters. Authentication Reject message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters disclosed by the embodiments of the present disclosure, the following parameters can be taken together in the Authentication Reject message: #EAPmessage. Service Request message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be taken together in the Service Request message: #ngKSI, Service type, 5G-S-TMSI, Uplink data status, PDU session status, Allowed PDU session status, NAS message container. Service Accept message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be taken together in the Service Accept message: #PDU session status, PDU session reactivation result, PDU session reactivation result error cause, EAP message, and T3448 value. - Service Reject message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters disclosed by the aspects of the present disclosure, any of the following parameters may be taken together in the Service Reject message: #5GMM cause, PDU session status, T3346 value, EAP message, T3448 value, and CAG information list. -Configuration Update Command message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters disclosed by the embodiments of the present disclosure, any of the following parameters may be taken together in the Configuration Update Command message: #Configuration update indication, 5G-GUTI, TAI list, Allowed NSSAI, Service area list, Full name for network, Short name for network, Local time zone, Universal time and local time zone, Network daylight saving time, LADN information, MICO indication, Network slicing indication, Configured NSSAI, Rejected NSSAI, Operator-defined access category definitions, SMS indication, CAG information list, UE radio capability ID deletion indication, 5GS registration result, Truncated 5G-S-TMSI configuration, Additional configuration indication, Extended rejected NSSAI. -Configuration Update Complete message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters disclosed by the embodiments of the present disclosure, the following parameters may be taken together in the Configuration Update Complete message: #Configuration update complete message identity.

[0452] (User equipment (UE)) FIG. 9 is a block diagram illustrating the main components of a mobile device 3 (UE 3). As shown, the UE 3 includes a transceiver circuit 31 operable to transmit and receive signals to and from connected node(s) via one or more antennas 32. The UE 3 may further include a user interface 34 for inputting and outputting information from and to the outside. Although not necessarily shown in FIG. 9, the UE 3 may have all the usual functions of a conventional mobile device, which may be provided by any one or any combination of hardware, software, and firmware, as needed. The software may be pre-installed in memory and / or downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). The controller 33 controls the operation of the UE 3 in accordance with software stored in the memory 36. This software includes, among other things, an operating system 361 and a communications control module 362 having at least one transceiver control module 3621. The communications control module 362 (using its transceiver control module 3621) is responsible for handling (generating / sending / receiving) signaling and uplink / downlink data packets between the UE 3 and other nodes, such as the (R)AN node 5 and the AMF 70. Such signaling may include, for example, appropriately formatted signaling messages (e.g., registration request messages and associated response messages) related to access and mobility management procedures (for the UE 3). The controller 33 interoperates with one or more Universal Subscriber Identity Modules (USIMs) 35. If equipped with multiple USIMs 35, the controller 33 may activate only one USIM 35 or may activate multiple USIMs 35 simultaneously.

[0453] The UE 3 may, for example, be compatible with a Non-Public Network (NPN), which may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0454] UE3 may be, for example, an item of equipment for production or manufacturing, and / or an energy-related item of machinery (e.g., equipment or machinery such as boilers, engines, turbines, solar panels, wind turbines, hydroelectric generators, thermal power plants, nuclear generators, batteries, nuclear systems and / or related equipment, heavy electrical equipment, pumps including vacuum pumps, compressors, fans, blowers, hydraulic equipment, pneumatic equipment, metalworking machinery, manipulators, robots and / or application systems thereof, tools, moulds or dies, rolls, material handling equipment, textile machinery, sewing machines, printing and / or related machinery, paper converting machinery, chemical machinery, mining and / or construction machinery and / or related facilities, machinery and / or implements for agriculture, forestry and / or fisheries, safety and / or environmental protection equipment, tractors, precision bearings, chains, gears, power transmission equipment, lubrication equipment, valves, pipe fittings, and / or application systems for any of the aforementioned equipment or machines).

[0455] UE 3 may be, for example, an item of transportation equipment (e.g., rail cars, automobiles, motorcycles, bicycles, trains, buses, carts, rickshaws, ships and other watercraft, aircraft, rockets, satellites, drones, balloons, and other transportation equipment).

[0456] UE 3 may be, for example, an item of information and communications equipment (eg, information and communications equipment such as electronic computers and related equipment, communications and related equipment, electronic components, etc.).

[0457] UE3 may be, for example, a refrigerator, a refrigerator application product, a goods and / or service industry equipment item, a vending machine, an automated service machine, an office machine, a consumer electronic device and an electronic appliance (e.g., a consumer electrical appliance such as audio equipment, video equipment, a speaker, a radio, a television, a microwave oven, a rice cooker, a coffee machine, a dishwasher, a washing machine, a dryer, an electronic fan or related appliance, a vacuum cleaner, etc.).

[0458] The UE 3 may be, for example, an electrical application system or device (eg, an electrical application system or device such as an X-ray system, a particle accelerator, a radioisotope device, a sonic device, an electromagnetic application device, an electrical application device, etc.).

[0459] The UE3 may be, for example, an electronic lamp, lighting fixture, measuring instrument, analyzer, tester, or surveying or sensing equipment (e.g., surveying or sensing equipment such as smoke detectors, motion sensors, radio frequency tags, etc.), a wristwatch or watch, inspection equipment, optical devices, medical equipment and / or systems, weapons, cutlery items, hand tools, etc.

[0460] UE3 may be, for example, a wireless-equipped personal digital assistant or related equipment (such as a wireless card or module designed to be attached to or inserted into another electronic device (e.g., a personal computer, an electrical measuring instrument)).

[0461] The UE 3 may be part of a device or system that uses various wired and / or wireless communication technologies to provide the applications, services, and solutions described below in relation to the "internet of things (IoT)."

[0462] Internet of Things devices (or "things") can be equipped with appropriate electronics, software, sensors, network connections, etc. that enable these devices to collect and exchange data with each other and with other communicating devices. IoT devices can include automated machines that follow software instructions stored in internal memory. IoT devices may operate without the need for human direction or interaction. IoT devices may also remain stationary and / or inactive for long periods of time. IoT devices can be implemented as part of (typically) stationary equipment. IoT devices can also be incorporated into non-stationary equipment (e.g., vehicles) or attached to animals or people being monitored / tracked.

[0463] It will be understood that IoT technologies may be implemented on any communication device capable of connecting to a communication network to send / receive data, whether such communication device is controlled by human input or by software instructions stored in memory.

[0464] It will be appreciated that an IoT device may also be referred to as a Machine-Type Communication (MTC) device, or a Machine-to-Machine (M2M) communication device, or a Narrow Band-IoT UE (NB-IoT UE). It will be appreciated that a UE 3 may support one or more IoT or MTC applications.

[0465] The UE3 may be a smartphone or a wearable device (e.g., smart glasses, a smart watch, a smart ring, or an auditory device).

[0466] The UE3 may be an automobile, or a connected car, or an autonomous vehicle, or a vehicle device, or a motorcycle, or a V2X (Vehicle-to-Everything) communication module (e.g., a vehicle-to-vehicle communication module, a vehicle-to-infrastructure communication module, a vehicle-to-person communication module, and a vehicle-to-network communication module).

[0467] ((R)AN node) FIG. 10 is a block diagram illustrating the main components of an exemplary (R)AN node 5, e.g., a base station (eNB in ​​LTE, gNB in ​​5G, Beyond 5G base station, 6G base station). As shown, the (R)AN node 5 includes transceiver circuitry 51 operable to transmit and receive signals to and from connected UE(s) 3 via one or more antennas 52, and to transmit and receive signals to and from other network nodes (directly or indirectly) via a network interface 53. A controller 54 controls operation of the (R)AN node 5 according to software stored in memory 55. The software may be pre-installed in the memory and / or may be downloaded, for example, via a telecommunications network or from a removable memory device (e.g., RMD). The software includes, among other things, an operating system 551 and a communications control module 552 having at least a transceiver control module 5521.

[0468] The communication control module 552 (using its transceiver control sub-module) is responsible for handling (generating / sending / receiving) signaling (e.g., directly or indirectly) between the (R)AN node 5 and other nodes, such as a UE 3, another (R)AN node 5, an AMF 70, and a UPF 72. This signaling may include, for example, appropriately formatted signaling messages related to the radio connection and connection with the core network 7 (for a particular UE 3), in particular, connection establishment and maintenance (e.g., RRC connection establishment and other RRC messages), NG Application Protocol (NGAP) messages (i.e., messages over the N2 reference point), and Xn application protocol (XnAP) messages (i.e., messages over the Xn reference point), etc. Such signaling may also include, for example, broadcast information (e.g., master information and system information) in the transmit case.

[0469] When implemented, the controller 54 is also configured (by software or hardware) to handle UE mobility estimation and / or related tasks such as motion trajectory estimation.

[0470] The (R)AN node 5 may correspond to a Non-Public Network (NPN), which may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0471] (System overview of (R)AN Node 5 based on O-RAN architecture) FIG. 11 illustrates schematically an (R)AN node 5 based on an O-RAN architecture to which aspects of the (R)AN node 5 may be applied.

[0472] An (R)AN node 5 based on the O-RAN architecture is an overview of a system in which the (R)AN node is divided into a Radio Unit (RU) 60, a Distributed Unit (DU) 61, and a Centralized Unit (CU) 62. In some aspects, each unit can be combined. For example, the RU 60 can be combined with the DU 61 as a combined / combined unit, and the DU 61 can be combined with the CU 62 as another combined / combined unit. Any functionality described for a unit (e.g., one of the RU 60, DU 61, and CU 62) can be implemented in the combined / combined unit. Furthermore, the CU 62 can be separated into two functional units: a CU Control plane (CP) and a CU User plane (UP). The CU CP performs the control plane function in the (R)AN node 5. The CU UP performs the user plane function in the (R)AN node 5. Each CU CP is connected to the CU UP via an appropriate interface (such as a so-called "E1" interface).

[0473] The UE 3 and each serving RU 60 are connected via an appropriate air interface (e.g., the so-called "Uu" interface, etc.). Each RU 60 is connected to a DU 61 via an appropriate interface (e.g., the so-called "fronthaul," "open fronthaul," "F1" interface, etc.). Each DU 61 is connected to a CU 62 via an appropriate interface (e.g., the so-called "midhaul," "open midhaul," "E2" interface, etc.). Each CU 62 is also connected to a node in the core network 7 (e.g., a so-called core network node) via an appropriate interface (e.g., the so-called "backhaul," "open backhaul," "N2" / "N3" interface(s)), etc. The user plane part of the DU 61 may also be connected to the core network node 7 via an appropriate interface (e.g., the so-called "N3" interface(s)).

[0474] Depending on the functionality divided among the RU 60, DU 61, and CU 62, each unit provides a portion of the functionality provided by the (R)AN node 5. For example, the RU 60 may provide functionality for communicating with the UE 3 over the air interface, the DU 61 may provide functionality for supporting the MAC layer and the RLC layer, and the CU 62 may provide functionality for supporting the PDCP layer, the SDAP layer, and the RRC layer.

[0475] (Radio Unit (RU)) FIG. 12 is a block diagram illustrating the main components of an exemplary RU 60, e.g., the RU portion of a base station (e.g., an eNB in ​​LTE, a gNB in ​​5G, a Beyond 5G base station, or a 6G base station). As shown, the RU 60 includes transceiver circuitry 601 operable to transmit and receive signals to and from connected UE(s) 3 via one or more antennas 602 and to transmit and receive signals to and from other network nodes or units (directly or indirectly) via a network interface 603. A controller 604 controls the operation of the RU 60 in accordance with software stored in memory 605. The software may be pre-installed in the memory and / or may be downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). This software includes, among other things, an operating system 6051 and a communications control module 6052 having at least a transceiver control module 60521.

[0476] The communication control module 6052 (using its transceiver control sub-module) is responsible for handling (generating / sending / receiving) signaling (e.g., directly or indirectly) between the RU 60 and other nodes or units, such as a UE 3, another RU 60, and a DU 61. The signaling may include, for example, appropriately formatted signaling messages relating to the radio connection and connection with the RU 60 (for a particular UE 3), in particular relating to the MAC and RLC layers.

[0477] The controller 604, when implemented, is also configured (by software or hardware) to handle related tasks such as UE mobility estimation and / or motion trajectory estimation.

[0478] The RU 60 can be compatible with a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0479] As described above, the RU 60 can be integrated / combined as an integrated / combined unit with the DU 61. Any of the functions described for the RU 60 can be implemented in the integrated / combined unit.

[0480] (Distributed Unit (DU)) FIG. 13 is a block diagram illustrating the main components of an exemplary DU 61, e.g., the DU portion of a base station (eNB in ​​LTE, gNB in ​​5G, Beyond 5G base station, 6G base station). As shown, the device includes a transceiver circuit 611 operable to transmit and receive signals to and from other nodes or units (including the RU 60) via a network interface 612. A controller 613 controls the operation of the DU 61 in accordance with software stored in memory 614. The software may be pre-installed in memory 614 and / or may be downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). The software includes, among other things, an operating system 6141 and a communications control module 6142 having at least a transceiver control module 61421. The communication control module 6142 (using its transceiver control module 61421) is responsible for handling (generating / sending / receiving) signaling between the DU 61 and other nodes or units, such as the RU 60, and other nodes and units.

[0481] The DU 61 can support a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN). As described above, the DU 61 can be integrated / combined as an integrated / combined unit with the RU 60 or the CU 62. Any of the functions described for the DU 61 can be implemented in the integrated / combined unit.

[0482] (Centralized Unit (CU)) FIG. 14 is a block diagram illustrating the main components of an exemplary CU 62, e.g., the CU portion of a base station (e.g., an eNB in ​​LTE, a gNB in ​​5G, a Beyond 5G base station, or a 6G base station). As shown, the device includes a transceiver circuit 621 operable to transmit and receive signals to and from other nodes or units (including the DU 61) via a network interface 622. A controller 623 controls the operation of the CU 62 in accordance with software stored in memory 624. The software may be pre-installed in memory 624 and / or may be downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). The software includes, among other things, an operating system 6241 and a communications control module 6242 having at least a transceiver control module 62421. The communication control module 6242 (using its transceiver control module 62421) is responsible for handling (generating / sending / receiving) signaling between the CU 62 and other nodes or units, such as the DU 61, and other nodes and units.

[0483] The CU 62 may be compatible with a Non-Public Network (NPN), which may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0484] As mentioned above, the CU 62 can be integrated / combined as an integrated / combined unit with the DU 61. Any functionality described for the CU 62 can be implemented in the integrated / combined unit.

[0485] (AMF) 15 is a block diagram illustrating the major components of the AMF 70. As shown, the device includes a transceiver circuit 701 operable to transmit and receive signals to and from other nodes (including UE 3) via a network interface 702. A controller 703 controls the operation of the AMF 70 in accordance with software stored in memory 704. The software may be pre-installed in memory 704 and / or may be downloaded, for example, over a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). This software includes, among other things, an operating system 7041 and a communications control module 7042 having at least a transceiver control module 70421. The communications control module 7042 (using its transceiver control module 70421) is responsible for handling (generating / sending / receiving) signaling between the AMF 70 and other nodes, such as the UE 3 (e.g., via (R)AN node 5) and other core network nodes (including core network nodes in the UE 3's HPLMN when the UE 3 is roaming in). Such signaling may include, for example, appropriately formatted signaling messages (e.g., registration request messages and associated response messages) related to access and mobility management procedures (for the UE 3).

[0486] The AMF 70 can support a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0487] (SMF) 16 is a block diagram illustrating the major components of the SMF 71. As shown, the device includes a transceiver circuit 711 operable to transmit and receive signals to and from other nodes (including the AMF 70) via a network interface 712. A controller 713 controls the operation of the SMF 71 in accordance with software stored in a memory 714. The software may be pre-installed in the memory 714 and / or downloaded over a telecommunications network or from a removable memory device (RMD), for example. This software includes, among other things, an operating system 7141 and a communications control module 7142 having at least one transceiver control module 71421. The communications control module 7142 (using its transceiver control module 71421) is responsible for handling (generating / sending / receiving) signaling between the SMF 71 and other nodes, such as the UPF 72 and other core network nodes (including core network nodes in the UE 3's HPLMN when the UE 3 is roaming in). Such signaling may include, for example, appropriately formatted signaling messages (e.g., Hypertext Transfer Protocol (HTTP) restful methods based on service-based interfaces) relating to session management procedures (for UE3).

[0488] The SMF 71 can support a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0489] (UPF) 17 is a block diagram illustrating the main components of the UPF 72. As shown, the device includes a transceiver circuit 721 operable to transmit and receive signals to and from other nodes (including the SMF 71) via a network interface 722. A controller 723 controls the operation of the UPF 72 in accordance with software stored in a memory 724. The software may be pre-installed in the memory 724 and / or downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). This software includes, among other things, an operating system 7241 and a communications control module 7242 having at least one transceiver control module 72421. The communications control module 7242 (using its transceiver control module 72421) is responsible for handling (generating / sending / receiving) signaling between the UPF 72 and other nodes, such as the SMF 71 and other core network nodes (including core network nodes in the UE 3's HPLMN when the UE 3 is roaming). Such signaling may include, for example, appropriately formatted signaling messages (eg, GPRS Tunneling Protocol (GTP) for the user plane) relating to user data handling (for UE 3).

[0490] The UPF 72 can support a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0491] (PCF) 18 is a block diagram illustrating the main components of the PCF 73. As shown, the device includes a transceiver circuit 731 operable to transmit and receive signals to and from other nodes (including the AMF 70) via a network interface 732. A controller 733 controls the operation of the PCF 73 in accordance with software stored in a memory 734. The software may be pre-installed in the memory 734 and / or may be downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). This software includes, among other things, an operating system 7341 and a communications control module 7342 having at least a transceiver control module 73421. The communications control module 7342 (using its transceiver control module 73421) is responsible for handling (generating / sending / receiving) signaling between the PCF 73 and other nodes, such as the AMF 70, and other core network nodes (including core network nodes in the UE 3's HPLMN when the UE 3 is roaming in). Such signaling may include, for example, appropriately formatted signaling messages (eg, HTTP restful methods based on service-based interfaces) relating to policy management procedures (for the UE 3).

[0492] The PCF 73 can support a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0493] (NEF) 19 is a block diagram illustrating the major components of the NEF 74. As shown, the device includes a transceiver circuit 741 operable to transmit and receive signals to and from other nodes (including the UDM 75) via a network interface 742. A controller 743 controls the operation of the NEF 74 in accordance with software stored in memory 744. The software may be pre-installed in the memory 744 and / or downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). This software includes, among other things, an operating system 7441 and a communications control module 7442 having at least a transceiver control module 74421. The communications control module 7442 (using its transceiver control module 74421) is responsible for handling (generating / sending / receiving) signaling between the NEF 74 and other nodes, such as the UDM 75 and other core network nodes (including core network nodes in the UE 3's HPLMN when the UE 3 is roaming in). Such signaling may include, for example, appropriately formatted signaling messages (eg, HTTP restful methods based on service-based interfaces) relating to network exposure function procedures (for UE 3).

[0494] The NEF 74 can support a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0495] (UDM) FIG. 20 is a block diagram illustrating the major components of the UDM 75. As shown, the device includes a transceiver circuit 751 operable to transmit and receive signals to and from other nodes (including the AMF 70) via a network interface 752. A controller 753 controls the operation of the UDM 75 in accordance with software stored in memory 754. The software may be pre-installed in the memory 754 and / or downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). This software includes, among other things, an operating system 7541 and a communications control module 7542 having at least a transceiver control module 75421. The communications control module 7542 (using its transceiver control module 75421) is responsible for handling (generating / sending / receiving) signaling between the UDM 75 and other nodes, such as the AMF 70, and other core network nodes (including core network nodes in the UE 3's VPLMN when the UE 3 is roaming out). Such signaling may include, for example, suitably formatted signaling messages (eg, HTTP restful methods based on service-based interfaces) relating to mobility management procedures (for UE 3).

[0496] The UDM 75 can support a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0497] (NSSF) 21 is a block diagram illustrating the major components of the NSSF 76. As shown, the device includes a transceiver circuit 761 operable to transmit and receive signals to and from other nodes (including the AMF 70) via a network interface 762. A controller 763 controls the operation of the NSSF 76 in accordance with software stored in a memory 764. This software may be pre-installed in the memory 764 and / or downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). This software includes, among other things, an operating system 7641 and a communications control module 7642 having at least a transceiver control module 76421. The communications control module 7642 (using its transceiver control module 76421) is responsible for handling (generating / sending / receiving) signaling between the NSSF 76 and other nodes, such as the AMF 70, and other core network nodes (including core network nodes in the UE 3's HPLMN when the UE 3 is roaming). Such signaling may include, for example, appropriately formatted signaling messages (eg, HTTP restful methods based on service-based interfaces) relating to network data analysis function procedures (for UE3).

[0498] The NSSF 76 can support a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0499] (NSACF) 22 is a block diagram illustrating the major components of the NSACF 77. As shown, the device includes a transceiver circuit 771 operable to transmit and receive signals to and from other nodes (including the AMF 70 and SMF 71) via a network interface 772. A controller 773 controls the operation of the NSACF 77 in accordance with software stored in memory 774. This software may be pre-installed in the memory 774 and / or downloaded, for example, via a telecommunications network or from a removable data storage device (e.g., a removable memory device (RMD)). This software includes, among other things, an operating system 7741 and a communications control module 7742 having at least a transceiver control module 77421. The communications control module 7742 (using its transceiver control module 77421) is responsible for handling (generating / sending / receiving) signaling between the NSACF 77 and other nodes, such as the AMF 70, and core network nodes in the UE 3's HPLMN when the UE 3 is roaming. Such signaling may include, for example, appropriately formatted signaling messages (eg, HTTP restful methods based on service-based interfaces) relating to network data analysis function procedures (for UE3).

[0500] The NSACF 77 can accommodate a Non-Public Network (NPN), which can be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0501] (Modifications and Alternatives) Having described detailed embodiments above, those skilled in the art will appreciate that several variations and alterations can be made to the above embodiments while still benefiting from the disclosure embodied therein. By way of example only, some of these alternatives and variations are now described.

[0502] In the above description, for ease of understanding, the UE 3 and network devices are described as having several separate modules (such as a communications control module). While such modules may be provided in this manner in certain applications, such as in applications where an existing system is modified to implement the present disclosure, in other applications, such as in systems designed from the beginning with the features of the present invention in mind, such modules may be incorporated into an overall operating system or code and therefore may not be identified as separate entities. Such modules may be implemented in software, hardware, firmware, or a combination thereof.

[0503] Each controller may comprise any suitable form of processing circuitry, including, for example (but not limited to), one or more hardware-implemented computer processors, microprocessors, central processing units (CPUs), arithmetic logic units (ALUs), input / output (IO) circuitry, internal memory / cache (program and / or data), process registers, communication buses (e.g., control buses, data buses and / or address buses), direct memory access (DMA) functionality, hardware or software-implemented counters, pointers and / or timers, etc.

[0504] In the above embodiments, several software modules have been described. As will be appreciated by those skilled in the art, the software modules may be provided in compiled or uncompiled form and may be provided to the UE 3 and network devices as signals over a computer network or on a recording medium. Furthermore, the functionality performed by some or all of this software may be performed using one or more dedicated hardware circuits. However, the use of software modules is preferred because it facilitates updating the UE 3 and network devices to update their functionality.

[0505] In the above embodiments, 3GPP wireless communication (radio access) technologies are used. However, any other wireless communication technologies (e.g., WLAN, Wi-Fi, WiMAX, Bluetooth, etc.) and other fixed line communication technologies (e.g., BBF access, cable access, optical access, etc.) can also be used in accordance with the above embodiments.

[0506] Items of user equipment may include, for example, communication devices such as mobile phones, smartphones, user equipment, personal digital assistants, laptop / tablet computers, web browsers, e-book readers, etc. Such mobile devices (or more generally fixed devices) are typically operated by a user, although so-called "Internet of Things" (IoT) devices and similar machine-type communication (MTC) devices may also be connected to the network. For ease of explanation, this application refers to mobile devices (or UE), but it will be understood that the described techniques may be implemented in any communication device (mobile and / or generally fixed) capable of connecting to a communication network to send and receive data, regardless of whether such communication device is controlled by human input or software instructions stored in memory.

[0507] Various other variations will be apparent to those skilled in the art and will not be described in further detail here.

[0508] As will be appreciated by those skilled in the art, the present disclosure may be embodied as a method and a system, and thus may take the form of an entirely hardware embodiment, a software embodiment, or an embodiment combining software and hardware aspects.

[0509] It will be understood that each block of the block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a general-purpose computer, a special-purpose computer, or a processor of another programmable data processing apparatus to provide a mechanism such that the instructions, executed by the processor of the computer or other programmable data processing apparatus, cause the processor to implement the functions / acts specified in one or more blocks of the flowcharts and / or block diagrams. A general-purpose processor can be a microprocessor, but alternatively, the processor can be any conventional processor, controller, microcontroller, or state machine. A processor can also be implemented as a combination of computing devices, e.g., multiple microprocessors, one or more microprocessors, or any other such configuration.

[0510] The methods or algorithms described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. The software module may be RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. The storage medium may be coupled to the processor such that the processor can read information from, and write information to, the storage medium. Alternatively, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC.

[0511] The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the spirit or scope of the present disclosure. Thus, the present disclosure is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0512] Although the present disclosure has been shown and described in detail with reference to exemplary embodiments thereof, the present disclosure is not limited to these embodiments. It will be understood by those skilled in the art that various changes in form and details can be made without departing from the spirit and scope of the present disclosure as defined by this specification. For example, the above embodiments are not limited to 5GS, and these embodiments can also be applied to communication systems other than 5GS (e.g., 6G systems, 5G Beyond systems).

[0513] (Addendum) The exemplary aspects disclosed above can be explained in whole or in part as follows, but are not limited to the following: (Appendix 1) 1. A method of a communication device, comprising: receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); Determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; and continuing to send the second message if the S-NSSAI determines that it has the attribute; A method in which the second message includes an S-NSSAI for performing a procedure to confirm and update the number of UEs available per network slice. (Appendix 2) If the S-NSSAI determines that the S-NSSAI does not have the attribute, sending a second message is also included. The method described in Appendix 1. (Appendix 3) If the S-NSSAI determines that it has the attribute, sending a third message; The third message has a list including at least one S-NSSAI for which the procedure for checking and updating the number of available UEs per network slice has not been performed; 3. The method of claim 1 or 2, further comprising sending a third message, the S-NSSAI being included in the list. (Appendix 4) The third message is a registration accept message. The method described in Appendix 3. (Appendix 5) the first message is a registration request message, The second message is a Nnsacf_NSAC_NumOfUEsUpdate_Request message. 5. The method of any one of claims 1 to 4. (Appendix 6) receiving a fourth message including an S-NSSAI; and sending a fifth message including the S-NSSAI; and receiving a sixth message including information indicating that a maximum number of UEs registered for the S-NSSAI has been reached; and sending a seventh message having a Rejected NSSAI that includes the S-NSSAI; 6. The method of any one of claims 1 to 5. (Appendix 7) The fourth message is a PDU session establishment request message; The seventh message is a PDU session establishment reject message. The method described in Appendix 6. (Appendix 8) 1. A method of a communication device, comprising: receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); Determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; and if determining that the S-NSSAI has the attribute, sending a second message; A method in which the second message includes an S-NSSAI for performing a procedure to confirm and update the number of UEs available per network slice. (Appendix 9) the first message is a PDU session establishment request message; The second message is a Nnsacf_NSAC_NumOfUEsUpdate_Request message. The method described in Appendix 8. (Appendix 10) The S-NSSAI in the first message is included in the list, The list includes at least one S-NSSAI for which the procedure for checking and updating the number of available UEs per network slice has not been performed; 10. The method according to claim 8 or 9. (Appendix 11) receiving a third message including information indicating that a maximum number of UEs registered for the S-NSSAI has been reached; and and transmitting a fourth message including the information. 11. The method of any one of claims 8 to 10. (Appendix 12) The third message is a Nnsacf_NSAC_NumOfUEsUpdate_Response message. The method described in Appendix 11. (Appendix 13) A method for User Equipment (UE), comprising: transmitting a first message including Single Network Slice Selection Assistance Information (S-NSSAI); receiving a second message having a list including at least one S-NSSAI for which a procedure for checking and updating the number of UEs available per network slice has not been performed, if the S-NSSAI has an attribute related to a maximum number of UEs simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; The S-NSSAI is included in the list of methods. (Appendix 14) the first message is a registration request message, The second message is a registration accept message. The method described in Appendix 13. (Appendix 15) sending a third message including the list, the third message being a PDU session establishment request message; receiving a fourth message when a maximum number of UEs registered for the S-NSSAI has been reached, the fourth message being a PDU session establishment reject message, the fourth message further including a Rejected NSSAI including the S-NSSAI; 15. The method according to claim 13 or 14. (Appendix 16) 1. A method of a communication device, comprising: receiving a first message from an Access and Mobility Management Function (AMF), the first message including Single Network Slice Selection Assistance Information (S-NSSAI); Determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; If it is determined that the S-NSSAI has the attribute, continuing to perform a procedure for checking and updating the number of UEs available per network slice for the S-NSSAI. (Appendix 17) sending a second message, The second message includes a list including at least one S-NSSAI for which the procedure for checking and updating the number of available UEs per network slice has not been performed; and The S-NSSAI is included in that list. sending a second message, the second message being a Nnsacf_NSAC_NumOfUEsUpdate_Response message; The method described in Appendix 16. (Appendix 18) receiving a third message from a Session Management Function (SMF) that includes the list; determining whether an S-NSSAI in the list has an attribute; If it is determined that the S-NSSAI has the attribute, performing a procedure for checking and updating the number of UEs available per network slice for the S-NSSAI; The method described in Appendix 17. (Appendix 19) receiving a third message from a Session Management Function (SMF) that includes an S-NSSAI; and determining whether the S-NSSAI has an attribute; If it is determined that the S-NSSAI has the attribute, performing a procedure for checking and updating the number of UEs available per network slice for the S-NSSAI. 18. The method according to claim 16 or 17. (Appendix 20) The first message is a Nnsacf_NSAC_NumOfUEsUpdate_Request message; 19. The method of any one of claims 16 to 19. (Appendix 21) 1. A method of a communication device, comprising: communicating with other communication devices; A method comprising: sending information to another communication device indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has attributes regarding the maximum number of user equipments that will simultaneously use the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. (Appendix 22) 1. A method of a communication device, comprising: communicating with other communication devices; A method comprising receiving information from another communication device indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has attributes regarding the maximum number of user equipments that will simultaneously use the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. (Appendix 23) A communication device, means for receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); A means for determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; means for continuing to send the second message if it is determined that the S-NSSAI has the attribute; A communications device, wherein the second message includes an S-NSSAI for performing a procedure for confirming and updating the number of UEs available per network slice. (Appendix 24) and means for transmitting a second message if it is determined that the S-NSSAI does not have the attribute. 24. The communication device of claim 23. (Appendix 25) means for transmitting a third message if it determines that the S-NSSAI has the attribute, The third message has a list including at least one S-NSSAI for which the procedure for checking and updating the number of available UEs per network slice has not been performed; and means for transmitting a third message, the S-NSSAI being included in the list; 25. The communication device of claim 23 or 24. (Appendix 26) The third message is a registration accept message. 26. The communication device of claim 25. (Appendix 27) the first message is a registration request message, The second message is a Nnsacf_NSAC_NumOfUEsUpdate_Request message. 27. A communication device according to any one of appendices 23 to 26. (Appendix 28) means for receiving a fourth message including the S-NSSAI; means for transmitting a fifth message including the S-NSSAI; means for receiving a sixth message including information indicating that a maximum number of UEs registered for the S-NSSAI has been reached; means for transmitting a seventh message having a Rejected NSSAI that includes the S-NSSAI; 28. The communication device of any one of appendices 23 to 27. (Appendix 29) The fourth message is a PDU session establishment request message; The seventh message is a PDU session establishment reject message. 29. The communication device of claim 28. (Appendix 30) A communication device, means for receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); A means for determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; A communications device comprising: a means for transmitting a second message when it is determined that the S-NSSAI has the attribute, the second message including an S-NSSAI for performing a procedure to confirm and update the number of UEs available for each network slice. (Appendix 31) the first message is a PDU session establishment request message; The second message is a Nnsacf_NSAC_NumOfUEsUpdate_Request message. 31. The communication device of claim 30. (Appendix 32) The S-NSSAI in the first message is included in the list, The list includes at least one S-NSSAI for which the procedure for checking and updating the number of available UEs per network slice has not been performed; 32. The communication device of claim 30 or 31. (Appendix 33) means for receiving a third message including information indicating that a maximum number of UEs registered for the S-NSSAI has been reached; means for transmitting a fourth message including the information; 33. The communication device of any one of appendices 30 to 32. (Appendix 34) The third message is a Nnsacf_NSAC_NumOfUEsUpdate_Response message. 34. The communication device of claim 33. (Appendix 35) User Equipment (UE), means for transmitting a first message including Single Network Slice Selection Assistance Information (S-NSSAI); means for receiving a second message having a list including at least one S-NSSAI, wherein if the S-NSSAI has an attribute related to a maximum number of UEs simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection, a procedure for checking and updating the number of UEs available per network slice has not been performed; The S-NSSAI is included in the list,UE. (Appendix 36) the first message is a registration request message, The second message is a registration accept message. UE as described in Appendix 35. (Appendix 37) means for sending a third message including the list, the third message is a PDU session establishment request message; a means for receiving a fourth message when a maximum number of UEs registered for the S-NSSAI has been reached, The fourth message is a PDU session establishment reject message, and the fourth message further comprising means for including a Rejected NSSAI that includes the S-NSSAI. 37. The UE according to claim 35 or 36. (Appendix 38) A communication device, means for receiving a first message from an Access and Mobility Management Function (AMF), the first message including Single Network Slice Selection Assistance Information (S-NSSAI); A means for determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; A communications device comprising: means for continuing to perform a procedure for confirming and updating the number of UEs available per network slice for the S-NSSAI when it is determined that the S-NSSAI has the attribute. (Appendix 39) a means for transmitting a second message, the means comprising: The second message includes a list including at least one S-NSSAI for which the procedure for checking and updating the number of available UEs per network slice has not been performed; and The S-NSSAI is included in that list. means for transmitting a second message, the second message being a Nnsacf_NSAC_NumOfUEsUpdate_Response message; 39. The communications device of claim 38. (Appendix 40) means for receiving a third message from a Session Management Function (SMF) that includes the list; means for determining whether an S-NSSAI in the list has a certain attribute; A communications device as described in Supplementary Note 39, further comprising: means for performing a procedure for confirming and updating the number of UEs available per network slice for the S-NSSAI when it is determined that the S-NSSAI has the attribute. (Appendix 41) means for receiving a third message including an S-NSSAI from a Session Management Function (SMF); means for determining whether the S-NSSAI has a certain attribute; and when it is determined that the S-NSSAI has the attribute, performing a procedure for confirming and updating the number of UEs available for each network slice for the S-NSSAI. 40. The communication device of claim 38 or 39. (Appendix 42) The first message is a Nnsacf_NSAC_NumOfUEsUpdate_Request message; 42. The communication device of any one of appendices 38 to 41. (Appendix 43) A communication device, means for communicating with other communication devices; A communications device comprising: means for transmitting, to another communications device, information indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has attributes regarding the maximum number of user equipments that simultaneously use the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. (Appendix 44) A communication device, means for communicating with other communication devices; A communications device comprising: means for receiving information from another communications device indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has attributes regarding the maximum number of user equipments that will simultaneously use the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection. (Appendix 45) 1. A method performed by a first communication device, comprising: receiving, from the second communication device, a first message regarding Network Slice Admission Control (NSAC) for a maximum number of User Equipment (UE) having at least one Protocol Data Unit (PDU) session and Packet Data Network (PDN) connection based on the UE establishing a PDU session / PDN connection associated with the network slice in the second communication device; A method comprising: performing NSAC for a maximum number of UEs having at least one PDU session / PDN connection. (Appendix 46) and further comprising: tracking a current number of UEs having at least one PDU session / PDN connection established in the network slice to ensure that the current number of UEs does not exceed a maximum number of UEs. The method described in Appendix 45. (Appendix 47) and further comprising: sending a second message to the second communication device based on a current number of UEs having at least one PDU session / PDN connection, the current number of UEs having at least one PDU session / PDN connection having already reached the maximum number of UEs. 46. ​​The method described in Appendix 46. (Appendix 48) 48. The method of any one of appendixes 45 to 47, wherein the first message is a Nnsacf_NSAC_NumOFUEsUpdate_Request message. (Appendix 49) 49. The method of any one of Clauses 45 to 48, wherein the second message is a response message. (Appendix 50) 50. The method of any one of claims 45 to 49, wherein the first communication device is a Network Slice Admission Control Function (NSACF). (Appendix 51) 51. The method of any one of claims 45 to 50, wherein the second communication device is a Session Management Function (SMF). (Appendix 52) A method performed by a second communication device, comprising: Based on a User Equipment (UE) establishing a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection associated with the network slice in the second communication device, sending a first message regarding Network Slice Admission Control (NSAC) for a maximum number of UEs having at least one PDU session / PDN connection to the first communication device; A method comprising: receiving a second message from a first communication device based on a first message received by the first communication device and a current number of UEs having at least one PDU session / PDN connection having already reached a maximum number of UEs. (Appendix 53) and further including transmitting a reason regarding the number of UEs in the network slice based on the fact that the number of UEs having at least one PDU session / PDN connection has already reached a maximum number and receiving a second message from the first communication device. 52. The method described in Appendix 52. (Appendix 54) 54. The method of claim 52 or 53, wherein the first message is a Nnsacf_NSAC_NumOFUEsUpdate_Request message. (Appendix 55) 55. The method of any one of Clauses 52 to 54, wherein the second message is a response message. (Appendix 56) 56. The method of any one of claims 52 to 55, wherein the first communication device is a Network Slice Admission Control Function (NSACF). (Appendix 57) 57. The method of any one of claims 52 to 56, wherein the second communication device is a Session Management Function (SMF).

[0514] This application claims the benefit of priority to Indian Patent Application No. 202311006516, filed on February 1, 2023, the disclosure of which is incorporated herein by reference in its entirety. [Explanation of symbols]

[0515] 20 Data Network 201 CSCF 3UE 31 Transceiver Circuit 32 Antenna 33 Controller 34 User Interface 35 USIM 36 memory 361 Operating Systems 362 Communication Control Module 3621 Transceiver Control Module 5 (R)AN nodes 51 Transceiver circuit 52 Antenna 53 Network Interface 54 Controller 55 memory 551 Operating Systems 552 Communication Control Module 5521 Transceiver Control Module 60RU 601 Transceiver Circuit 602 Antenna 603 Network Interface 604 Controller 605 memory 6051 Operating System 6052 Communication Control Module 60521 Transceiver Control Module 61 DU 611 Transceiver Circuit 612 Network Interface 613 Controller 614 memory 6141 Operating System 6142 Communication Control Module 61421 Transceiver Control Module 62 CU 621 Transceiver Circuit 622 Network Interface 623 Controller 624 memory 6241 Operating System 6242 Communication Control Module 62421 Transceiver Control Module 7 Core Network 70 AMF 701 Transceiver Circuit 702 Network Interface 703 Controller 704 memory 7041 Operating System 7042 Communication Control Module 70421 Transceiver Control Module 71 SMF 711 Transceiver Circuit 712 Network Interface 713 Controller 714 memory 7141 Operating System 7142 Communication Control Module 71421 Transceiver Control Module 72 UPF 721 Transceiver Circuit 722 Network Interface 723 Controller 724 memory 7241 Operating System 7242 Communication Control Module 72421 Transceiver Control Module 73 PCF 731 Transceiver Circuit 732 Network Interface 733 Controller 734 memory 7341 Operating System 7342 Communication Control Module 73421 Transceiver Control Module 74 NEF 741 Transceiver Circuit 742 Network Interface 743 Controller 744 memory 7441 Operating System 7442 Communication Control Module 74421 Transceiver Control Module 75 UDM 751 Transceiver Circuit 752 Network Interface 753 Controller 754 memory 7541 Operating Systems 7542 Communication Control Module 75421 Transceiver Control Module 76 NSSF 761 Transceiver Circuit 762 Network Interface 763 Controller 764 memory 7641 Operating System 7642 Communication Control Module 76421 Transceiver Control Module 77 NSACF 771 Transceiver Circuit 772 Network Interface 773 Controller 774 memory 7741 Operating System 7742 Communication Control Module 77421 Transceiver Control Module

Claims

1. receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); Determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using a network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; continuing to send a second message if the S-NSSAI determines that the S-NSSAI has the attribute; The second message includes the S-NSSAI for performing a procedure to confirm and update the number of UEs available per network slice. Method of communication device.

2. If it is determined that the S-NSSAI does not have the attribute, sending the second message. The method of claim 1.

3. sending a third message if it is determined that the S-NSSAI has the attribute; the third message includes a list including at least one S-NSSAI for which a procedure for checking and updating the number of UEs available per network slice has not been performed; and sending a third message, the S-NSSAI being included in the list.

3. The method according to claim 1 or 2.

4. the third message is a registration accept message; The method of claim 3.

5. the first message is a registration request message, The second message is an Nnsacf_NSAC_NumOfUEsUpdate_Request message; 5. The method according to any one of claims 1 to 4.

6. receiving a fourth message including the S-NSSAI; and sending a fifth message including the S-NSSAI; and receiving a sixth message including information indicating that a maximum number of UEs registered for the S-NSSAI has been reached; and transmitting a seventh message having a Rejected NSSAI that includes the S-NSSAI; 6. The method according to any one of claims 1 to 5.

7. the fourth message is a PDU session establishment request message; the seventh message is a PDU session establishment reject message; The method of claim 6.

8. receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); Determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using a network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; sending a second message if it is determined that the S-NSSAI has the attribute; The second message includes the S-NSSAI for performing a procedure to confirm and update the number of UEs available per network slice. Method of communication device.

9. the first message is a PDU session establishment request message; The second message is an Nnsacf_NSAC_NumOfUEsUpdate_Request message; The method of claim 8.

10. the S-NSSAI in the first message is included in a list; The list includes at least one S-NSSAI for which the procedure for checking and updating the number of UEs available per network slice has not been performed.

10. The method according to claim 8 or 9.

11. receiving a third message including information indicating that a maximum number of UEs registered for the S-NSSAI has been reached; and transmitting a fourth message including the information.

11. The method according to any one of claims 8 to 10.

12. The third message is an Nnsacf_NSAC_NumOfUEsUpdate_Response message. The method of claim 11.

13. transmitting a first message including Single Network Slice Selection Assistance Information (S-NSSAI); receiving a second message having a list including at least one S-NSSAI for which a procedure for checking and updating the number of UEs available per network slice has not been performed, if the S-NSSAI has an attribute related to a maximum number of UEs simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; The S-NSSAI is included in the list. User Equipment (UE) methods.

14. the first message is a registration request message, the second message is a registration accept message; The method of claim 13.

15. sending a third message including the list, wherein the third message is a PDU session establishment request message; and receiving a fourth message when a maximum number of UEs registered for the S-NSSAI has been reached, the fourth message being a PDU session establishment reject message and having a Rejected NSSAI that includes the S-NSSAI; 15. The method of claim 13 or 14.

16. receiving a first message from an Access and Mobility Management Function (AMF), the first message including Single Network Slice Selection Assistance Information (S-NSSAI); and Determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using a network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; If it is determined that the S-NSSAI has the attribute, continuing to perform a confirmation and update procedure of the number of UEs available per network slice for the S-NSSAI. Method of communication device.

17. sending a second message, The second message further includes a list including at least one S-NSSAI for which a procedure for checking and updating the number of available UEs per network slice has not been performed; the S-NSSAI is included in the list; sending a second message, wherein the second message is an Nnsacf_NSAC_NumOfUEsUpdate_Response message; 17. The method of claim 16.

18. receiving a third message from a Session Management Function (SMF) including the list; and determining whether the S-NSSAI in the list has the attribute; If it is determined that the S-NSSAI has the attribute, performing a procedure for checking and updating the number of UEs available per network slice for the S-NSSAI.

18. The method of claim 17.

19. receiving a third message from a Session Management Function (SMF) including the S-NSSAI; and determining whether the S-NSSAI has the attribute; If it is determined that the S-NSSAI has the attribute, performing a procedure for checking and updating the number of UEs available per network slice for the S-NSSAI.

18. The method of claim 16 or 17.

20. The first message is an Nnsacf_NSAC_NumOfUEsUpdate_Request message; 20. The method of any one of claims 16 to 19.

21. communicating with other communication devices; transmitting, to the other communication device, information indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has an attribute related to a maximum number of user equipments simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; Method of communication device.

22. communicating with other communication devices; receiving, from the other communication device, information indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has an attribute related to a maximum number of user equipments simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; Method of communication device.

23. means for receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); A means for determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using a network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; means for continuing to send a second message if it is determined that the S-NSSAI has the attribute; The second message includes the S-NSSAI for performing a procedure to confirm and update the number of UEs available per network slice. Communication equipment.

24. means for transmitting the second message when it is determined that the S-NSSAI does not have the attribute; 24. The communication device of claim 23.

25. means for sending a third message when determining that the S-NSSAI has the attribute, the third message comprises a list including at least one S-NSSAI for which a procedure for checking and updating the number of available UEs per network slice has not been performed; means for transmitting a third message, the S-NSSAI being included in the list; 25. A communication device according to claim 23 or 24.

26. the third message is a registration accept message; 26. The communication device of claim 25.

27. the first message is a registration request message, The second message is an Nnsacf_NSAC_NumOfUEsUpdate_Request message; 27. A communication device according to any one of claims 23 to 26.

28. means for receiving a fourth message including the S-NSSAI; means for transmitting a fifth message including the S-NSSAI; means for receiving a sixth message including information indicating that a maximum number of UEs registered for the S-NSSAI has been reached; means for transmitting a seventh message having a Rejected NSSAI that includes the S-NSSAI; 28. A communication device according to any one of claims 23 to 27.

29. the fourth message is a PDU session establishment request message; the seventh message is a PDU session establishment reject message; 29. The communication device of claim 28.

30. means for receiving a first message including Single Network Slice Selection Assistance Information (S-NSSAI); A means for determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using a network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; means for transmitting a second message when it is determined that the S-NSSAI has the attribute, wherein the second message includes the S-NSSAI for performing a procedure for confirming and updating the number of UEs available per network slice; Communication equipment.

31. the first message is a PDU session establishment request message; The second message is an Nnsacf_NSAC_NumOfUEsUpdate_Request message; 31. The communication device of claim 30.

32. the S-NSSAI in the first message is included in a list; The list includes at least one S-NSSAI for which the procedure for checking and updating the number of UEs available per network slice has not been performed.

32. A communication device according to claim 30 or 31.

33. means for receiving a third message including information indicating that a maximum number of UEs registered for the S-NSSAI has been reached; means for transmitting a fourth message including the information; 33. A communication device according to any one of claims 30 to 32.

34. The third message is an Nnsacf_NSAC_NumOfUEsUpdate_Response message.

34. The communication device of claim 33.

35. means for transmitting a first message including Single Network Slice Selection Assistance Information (S-NSSAI); means for receiving a second message having a list including at least one S-NSSAI, wherein if the S-NSSAI has an attribute related to a maximum number of UEs simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection, a procedure for checking and updating the number of UEs available per network slice has not been performed; The S-NSSAI is included in the list. User Equipment (UE).

36. the first message is a registration request message, the second message is a registration accept message; 36. The UE of claim 35.

37. means for transmitting the third message including the list, the third message is a PDU session establishment request message; means for receiving a fourth message when a maximum number of UEs registered for the S-NSSAI is reached, the fourth message is a PDU session establishment reject message, and the fourth message further comprises means for including a Rejected NSSAI that includes the S-NSSAI.

37. The UE of claim 35 or 36.

38. means for receiving a first message from an Access and Mobility Management Function (AMF), the first message including Single Network Slice Selection Assistance Information (S-NSSAI); A means for determining whether the S-NSSAI has an attribute related to a maximum number of User Equipments (UEs) simultaneously using a network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; and means for continuing to perform a procedure for checking and updating the number of UEs available per network slice for the S-NSSAI when it is determined that the S-NSSAI has the attribute. Communication equipment.

39. a means for transmitting a second message, The second message includes a list including at least one S-NSSAI for which a procedure for checking and updating the number of available UEs per network slice has not been performed; and the S-NSSAI is included in the list; means for transmitting a second message, wherein the second message is an Nnsacf_NSAC_NumOfUEsUpdate_Response message; 39. The communication device of claim 38.

40. means for receiving a third message from a Session Management Function (SMF) that includes the list; means for determining whether the S-NSSAI in the list has the attribute; When it is determined that the S-NSSAI has the attribute, a means for performing a confirmation and update procedure of the number of UEs available for each network slice for the S-NSSAI is further provided.

40. The communication device of claim 39.

41. means for receiving a third message including the S-NSSAI from a Session Management Function (SMF); means for determining whether the S-NSSAI has the attribute; When it is determined that the S-NSSAI has the attribute, a means for performing a confirmation and update procedure of the number of UEs available for each network slice for the S-NSSAI is further provided.

40. A communication device according to claim 38 or 39.

42. The first message is an Nnsacf_NSAC_NumOfUEsUpdate_Request message; 42. A communication device according to any one of claims 38 to 41.

43. means for communicating with other communication devices; means for transmitting, to the other communication device, information indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has an attribute related to a maximum number of user equipments simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; Communication equipment.

44. means for communicating with other communication devices; means for receiving, from the other communication device, information indicating that Single Network Slice Selection Assistance Information (S-NSSAI) has an attribute related to a maximum number of user equipments simultaneously using the network slice for at least one of a Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection; Communication equipment.

45. receiving, from a second communication device, a first message regarding Network Slice Admission Control (NSAC) for a maximum number of User Equipments (UEs) having at least one Protocol Data Unit (PDU) session and a Packet Data Network (PDN) connection based on the UE establishing a PDU session / PDN connection associated with a network slice in the second communication device; performing NSAC for a maximum number of UEs having at least one PDU session / PDN connection; A method performed by a first communication device.

46. and further comprising tracking a current number of UEs having at least one PDU session / PDN connection established in the network slice to ensure that the current number of UEs does not exceed a maximum number of UEs.

46. ​​The method of claim 45.

47. Further comprising: sending a second message to the second communication device based on the current number of UEs having at least one PDU session / PDN connection, the current number having reached the maximum number of UEs; 47. The method of claim 46.

48. 48. The method of any one of claims 45 to 47, wherein the first message is a Nnsacf_NSAC_NumOFUEsUpdate_Request message.

49. 49. The method of any one of claims 45 to 48, wherein the second message is a response message.

50. 50. The method of any one of claims 45 to 49, wherein the first communication device is a Network Slice Admission Control Function (NSACF).

51. 51. The method of any one of claims 45 to 50, wherein the second communication device is a Session Management Function (SMF).

52. Based on a User Equipment (UE) establishing a Protocol Data Unit (PDU) session / Packet Data Network (PDN) connection associated with the network slice in the second communication device, sending a first message for Network Slice Admission Control (NSAC) for a maximum number of UEs having at least one PDU session / PDN connection to the first communication device; receiving a second message from the first communication device based on the first message received by the first communication device and the current number of UEs having at least one PDU session / PDN connection having reached the maximum number of UEs; A method performed by a second communication device.

53. Further comprising: transmitting a reason regarding the number of UEs in the network slice based on the fact that the maximum number of UEs having at least one PDU session / PDN connection has already been reached and receiving the second message from the first communication device.

53. The method of claim 52.

54. 54. The method of claim 52 or 53, wherein the first message is a Nnsacf_NSAC_NumOFUEsUpdate_Request message.

55. 55. The method of any one of claims 52 to 54, wherein the second message is a response message.

56. 56. The method of any one of claims 52 to 55, wherein the first communication device is a Network Slice Admission Control Function (NSACF).

57. 57. A method according to any one of claims 52 to 56, wherein the second communication device is a Session Management Function (SMF).

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