Method of user equipment, method of network node, user equipment, and network node

Abstract

An aspect of this disclosure includes a method of a User Equipment (UE). The method includes performing a registration procedure using a 5G Femtocell. Another aspect of this disclosure includes a method of a network node. The method includes performing a registration procedure using a 5G Femtocell.

Description

METHOD OF USER EQUIPMENT, METHOD OF NETWORK NODE, USER EQUIPMENT, AND NETWORK NODE

[0001] The present disclosure relates to a method of a User Equipment (UE), a method of a network node, a User Equipment (UE), a network node etc.

[0002] High bandwidth and throughput with 5G are required indoors to enable new immersive applications such as AR / VR / MR, etc. While a lot of capacity is required indoor, outdoor to indoor coverage with 5G mid and high-bands is limited.

[0003] NPL 1: 3GPP TR 21.905: "Vocabulary for 3GPP Specifications", V17.1.0 (2021-12) 　　NPL 2: 3GPP TS 33.320: "Security of Home Node B (HNB) / Home evolved Node B (HeNB)", V17.0.0 (2022-03) 　　NPL 3: 3GPP TS 23.003: "Numbering, addressing and identification". V18.2.0 (2023-06) 　　NPL 4: 3GPP TS 23.501: "System architecture for the 5G System (5GS)". V18.1.0 (2023-03) 　　NPL 5: 3GPP TS 23.502: "Procedures for the 5G System (5GS)". V18.1.1 (2023-04) 　　NPL 6: 3GPP TS 23.503: "Policy and charging control framework for the 5G System (5GS) Stage 2". V18.1.0 (2023-03) 　　NPL 7: 3GPP TS 24.501: "Non-Access-Stratum (NAS) protocol for 5G System (5GS) Stage 3". V18.2.1 　　NPL 8: 3GPP TS 33.501: "Security architecture and procedures for 5G system". V18.2.0 (2023-06) 　　NPL 9: 3GPP TS 37.340: "Multi-connectivity Stage 2". V17.5.0 (2023-06) 　　NPL 10: 3GPP TS 38.413: "NG Application Protocol (NGAP)". V17.5.0 (2023-06)

[0004] Although there is strong market demand for 5G Femtocell deployments, the current 3GPP standard for 5G system does not support 5G Femtocell access. Lack of 5G Femtocell support may prevent from deploying a cost-effective way to improve 5G indoor coverage.

[0005] In a first aspect, the present disclosure provides a method of a User Equipment (UE) including: 　　performing a registration procedure using a 5G Femtocell.

[0006] In a second aspect, the present disclosure provides a method of a network node including: 　　performing a registration procedure using a 5G Femtocell.

[0007] In a third aspect, the present disclosure provides a method of a network node including: 　　performing a 5G Femtocell setup procedure.

[0008] In a fourth aspect, the present disclosure provides a User Equipment (UE) including: 　　means for performing a registration procedure using a 5G Femtocell.

[0009] In a fifth aspect, the present disclosure provides a network node including: 　　means for performing a registration procedure using a 5G Femtocell.

[0010] In a sixth aspect, the present disclosure provides a network node including: 　　means for performing a 5G Femtocell setup procedure.

[0011] Embodiments of the present disclosure will now be described, by way of example, with reference to the accompanying drawings.Fig. 1 is a diagram illustrating a configuration example of an Architecture supporting 5G Femtocell of a First example of a First Aspect.Fig. 2 is a diagram illustrating a configuration example of a Protocol stack of a First example of the First Aspect.Fig. 3 is a diagram illustrating a configuration example of a Protocol stack of a First example of the First Aspect.Fig. 4 is a diagram illustrating a configuration example of a Protocol stack of a First example of the First Aspect.Fig. 5 is a diagram illustrating a configuration example of a Protocol stack of a First example of the First Aspect.Fig. 6 is a Signaling diagram of a Second example of the First Aspect.Fig. 7 is a Signaling diagram of a Third example of the First Aspect.Fig. 8 is a formant of the CSG Identifier of a Third example of the First Aspect.Fig. 9 is an example of a CSG support indication bit of a Fourth example of the First Aspect.Fig. 10 is an example of an access restriction for 5G CAS cell of a Fourth example of the First Aspect.Fig. 11 is a Signaling diagram of a Fifth example of the First Aspect.Fig. 12 is a Signaling diagram of a Sixth example of the First Aspect.Fig. 13 is an Architecture supporting 5G Femtocell of a First example of a Second Aspect.Fig. 14 is a Signaling diagram of a Second example of the Second Aspect.Fig. 15 is a Signaling diagram of a Fifth example of the Second Aspect.Fig. 16 is a diagram illustrating a configuration example of an Architecture supporting 5G Femtocell of a First example of a Third Aspect.Fig. 17 is a Signaling diagram of a Second example of the Third Aspect.Fig. 18 is a Signaling diagram of a Fourth example of the Third Aspect.Fig. 19 is a Signaling diagram of a Fifth example of the Third Aspect.Fig. 20 is a diagram illustrating a configuration example of a system overview.Fig. 21 is a block diagram illustrating a configuration example of a UE.Fig. 22 is a block diagram illustrating a configuration example of an (R)AN node.Fig. 23 is a diagram illustrating a configuration example of a System overview of (R)AN node based on O-RAN architecture.Fig. 24 is a block diagram illustrating a configuration example of an RU.Fig. 25 is a block diagram illustrating a configuration example of a DU.Fig. 26 is a block diagram illustrating a configuration example of a CU.Fig. 27 is a block diagram illustrating a configuration example of an AMF.Fig. 28 is a block diagram illustrating a configuration example of an SMF.Fig. 29 is a block diagram illustrating a configuration example of a UPF.Fig. 30 is a block diagram illustrating a configuration example of a PCF.Fig. 31 is a block diagram illustrating a configuration example of an NWDAF.Fig. 32 is a block diagram illustrating a configuration example of a UDM.Fig. 33 is a block diagram illustrating a configuration example of an NSSF.Fig. 34 is a block diagram illustrating a configuration example of an AAA Server.Fig. 35 is a block diagram illustrating a configuration example of an NRF.Fig. 36 is a block diagram illustrating a configuration example of an AF.Description of Example Embodiments

[0012] Abbreviations 　　For the purposes of the present document, the abbreviations given in NPL 1 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in NPL 1.

[0013] 4G-GUTI　　4G Globally Unique Temporary UE Identity 5GC　　5G Core Network 5GLAN　　5G Local Area Network 5G HE AV　　5G Home Environment Authentication Vector 5G SE AV　　5G Serving Environment Authentication Vector 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 AMF-G　　Geographically selected Access and Mobility Management Function AMF-NG　　Non-Geographically selected Access and Mobility Management Function ANDSF　　Access Network Discovery and Selection Function AR　　Augmented Reality ARFCN　　Absolute radio-frequency channel number AS　　Access Stratum ASN　　Abstract Syntax Notation ATSSS　　Access Traffic Steering, Switching, Splitting ATSSS-LL　　ATSSS Low-Layer AuC　　Authentication Centre AUSF　　Authentication Server Function AUTN　　Authentication token BCCH　　Broadcast Control Channel BMCA　　Best Master Clock Algorithm BSF　　Binding Support Function CAG　　Closed Access Group CAPIF　　Common API Framework for 3GPP northbound APIs CDR　　Charging Data Record CHF　　Charging Function CN PDB　　Core Network Packet Delay Budget CP　　Control Plane CSG　　Closed Subscriber Group DAPS　　Dual Active Protocol Stacks DL　　Downlink DN　　Data Network DNAI　　DN Access Identifier DNN　　Data Network Name DRX　　Discontinuous Reception DSATSSS　　Dual Steer Access Traffic Steering, Switching, Splitting DSATSSS-LL　　Dual Steer Access Traffic Steering, Switching, Splitting- Low-Layer DSMA　　Dual Steer Multi Access DS-TT　　Device-side TSN translator ePDG　　evolved Packet Data Gateway EBI　　EPS Bearer Identity ECGI　　E-UTRAN Cell Global Identifier 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 GCI　　Global Cable Identifier GEO　　Geostationary Earth Orbit GFBR　　Guaranteed Flow Bit Rate GMLC　　Gateway Mobile Location Centre G-PDU　　GTP encapsulated user Plane Data Unit GPS　　Global Positioning System GPSI　　Generic Public Subscription Identifier GSO　　Geosynchronous Orbit GUAMI　　Globally Unique AMF Identifier GUTI　　Globally Unique Temporary UE Identity HPLMN　　Home Public Land Mobile Network HR　　Home Routed (roaming) HSS　　Home Subscriber Server IAB　　Integrated access and backhaul IEC　　International Electrotechnical Commission IMEI / TAC　　IMEI Type Allocation Code IMSI　　International Mobile Subscriber Identity IPsec　　Internet Protocol Security IPUPS　　Inter PLMN UP Security I-SMF　　Intermediate SMF ISO　　International Organization for Standardization I-UPF　　Intermediate UPF LADN　　Local Area Data Network LBO　　Local Break Out (roaming) LCS　　Location Service LEO　　Low Earth Orbit LMF　　Location Management Function LoA　　Level of Automation LPP　　LTE Positioning Protocol LRF　　Location Retrieval Function MA　　Multi Access MCC　　Mobile country code MCX　　Mission Critical Service MDBV　　Maximum Data Burst Volume ME　　Mobile Equipment MFBR　　Maximum Flow Bit Rate MICO　　Mobile Initiated Connection Only MINT　　Minimization of service interruption MITM　　Man In the Middle MME　　Mobility Management Entity MN　　Master Node MNC　　Mobile Network Code MNO　　Mobile Network Operator MOCN　　Multiple Operator Core Network MPS　　Multimedia Priority Service MPTCP　　Multi-Path TCP Protocol MR　　Mixed Reality MT　　Mobile Termination, Mobile Terminating, Mobile terminated N3IWF　　Non-3GPP InterWorking Function N3GPP　　Non-3GPP access N5CW　　Non-5G-Capable over WLAN NAI　　Network Access Identifier NAS　　Non-Access-Stratum NAT　　Network Address Translation NCGI　　NR Cell Global Identity NCI　　NR Cell Identity NEF　　Network Exposure Function NF　　Network Function NGAP　　Next Generation Application Protocol NGSO　　Non-Geosynchronous Orbit NID　　Network identifier NMEA　　National Marine Electronics Association NPN　　Non-Public Network NR　　New Radio NSAG　　Network Slice Access Stratum Group 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 NSSRG　　Network Slice Simultaneous Registration Group NW-TT　　Network-side TSN translator NWDAF　　Network Data Analytics Function PCF　　Policy Control Function PCO　　Protocol Configuration Options PCRF　　Policy and Charging Rules Function PDB　　Packet Delay Budget 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 ProSe　　Proximity based Services PSA　　PDU Session Anchor PTP　　Precision Time Protocol QFI　　QoS Flow Identifier QoE　　Quality of Experience RACS　　Radio Capabilities Signalling optimisation (R)AN　　(Radio) Access Network RAT　　Radio Access Technology RFID　　Radio Frequency Identification RG　　Residential Gateway RIM　　Remote Interference Management RQA　　Reflective QoS Attribute RQI　　Reflective QoS Indication RRC　　Radio Resource Control RSC　　Relay Service Code RSD　　Route Selection Descriptor RSN　　Redundancy Sequence Number RSRP　　Reference Signal Received Power RSRQ　　Reference Signal Received Quality RTT　　Round-Trip Time RVAS　　Roaming Value Added Service SA NR　　Standalone New Radio SBA　　Service Based Architecture SBI　　Service Based Interface SCP　　Service Communication Proxy SD　　Slice Differentiator SEAF　　Security Anchor Functionality SENSE　　Signal Level Enhanced Network Selection SEPP　　Security Edge Protection Proxy SGW　　Serving Gateway SIB　　System Information Block SINR　　Signal to Interference plus Noise Ratio SLA　　Service Level Agreement SMF　　Session Management Function SMS　　Short Message Service SMSF　　Short Message Service Function SN　　Sequence Number SN　　Secondary Node 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 TAU　　Tracking Area Update TEID　　Tunnel Endpoint Identifier TMGI　　Temporary Mobile Group Identity TMSI　　Temporary Mobile Subscriber Identity 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 UCU　　UE Configuration Update UDM　　Unified Data Management UDR　　Unified Data Repository UDSF　　Unstructured Data Storage Function UE　　User Equipment UL　　Uplink UL CL　　Uplink Classifier UPF　　User Plane Function UPSI　　UE Policy Section Identifier URLLC　　Ultra Reliable Low Latency Communication URRP-AMF　　UE Reachability Request Parameter for AMF URSP　　UE Route Selection Policy USIM　　User Services Identity Module VID　　VLAN Identifier VLAN　　Virtual Local Area Network VPLMN　　Visited Public Land Mobile Network VR　　Virtual Reality 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 WPT　　Wireless Power Transfer

[0014] Definitions 　　For the purposes of the present document, the terms and definitions given in NPL 1 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in NPL 1.

[0015] General 　　Those skilled in the art will appreciate that elements in the figures are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the figures by conventional symbols, and the figures may show only those specific details that are pertinent to understanding the Aspects of the present disclosure so as not to obscure the figures with details that will be readily apparent to those skilled in the art having the benefit of the description herein.

[0016] For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the Aspect illustrated in the figures and specific language will be used to describe them. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Such alterations and further modifications in the illustrated system, and such further applications of the principles of the disclosure as would normally occur to those skilled in the art are to be construed as being within the scope of the present disclosure.

[0017] The terms "comprises", "comprising", or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such a process or method. Similarly, one or more devices or entities or sub-systems or elements or structures or components preceded by "comprises... a" does not, without more constraints, preclude the existence of other devices, sub-systems, elements, structures, components, additional devices, additional sub-systems, additional elements, additional structures or additional components. Appearances of the phrase "in an Aspect", "in another Aspect" and similar language throughout this specification may, but not necessarily do, all refer to the same Aspect.

[0018] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. The system, methods, and examples provided herein are only illustrative and not intended to be limiting.

[0019] In the following specification and the claims, reference will be made to a number of terms, which may be defined to have the following meanings. The singular forms "a", "an", and "the" include plural references unless the context clearly dictates otherwise.

[0020] As used herein, information is associated with data and knowledge, as data is meaningful information and represents the values attributed to parameters. Further knowledge signifies understanding of an abstract or concrete concept. Note that this example system is simplified to facilitate description of the disclosed subject matter and is not intended to limit the scope of this disclosure. Other devices, systems, and configurations may be used to implement the Aspects disclosed herein in addition to, or instead of, a system, and all such Aspects are contemplated as within the scope of the present disclosure.

[0021] Each of Aspects and elements included in the each of Aspects described below may be implemented independently or in combination with any other. These Aspects include novel characteristics different from one another. Accordingly, these Aspects contribute to achieving objects or solving problems different from one another and contribute to obtaining advantages different from one another.

[0022] Any lists described in following aspects include at least one parameter or multiple parameters.

[0023] The expression "A and / or B" in this disclosure may mean "at least one of A or B". 　　The definition of parameter(s) in each Aspect may be referred each other.

[0024] Although this disclosure discloses a mechanism to establish multiple data plane connections in the 5GS, all mechanisms in this disclosure can equally apply to the EPS and / or any other system as well. In a case all mechanisms in this disclosure are to apply to the EPS, the following terminology conversions apply: ●　　gNB → eNodeB ●　　AMF → MME ●　　SMF → MME or SGW or PGW or combined SGW and PGW or SMF + PGW-C in a case of interworking with EPS ●　　UPF → SGW-U or PGW-U or combined SGW-U and PGW-U or UPF + PGW-U in a case of interworking with EPS ●　　UDM → HSS ●　　PCF → PCRF ●　　NRF → 3GPP DNS Server ●　　NGAP → S1AP ●　　XnAP → X2AP ●　　Any NGAP messages → Respective S1AP messages ●　　Any XnAP messages → Respective X2AP messages ●　　Registration Request message → Attach Request message or TAU Request message ●　　Any AMF service-related messages (ex. Namf_Communication_NonUeN2InfoNotify) → GTP-C messages ●　　Any UDM service-related messages (ex. Nudm_SDM_Notification) → DIAMETER messages ●　　5G-GUTI → GUTI ●　　5G-S-TMSI → S-TMSI ●　　5G Femtocell → Home eNodeB

[0025] In this disclosure, the 5G Femtocell may mean the 5G base station deployed in a private premise and connected to the PLMN or the NPN. The 5G Femtocell may support NR NG-RAN or E-UTRAN.

[0026] The 5G Femtocell may be expressed by different ways, for example, Femto, 5G Femto, 5G HgNB, 5G Home gNB, 5GHeNodeB, 5G Home eNodeB.

[0027] An example object of this disclosure is to provide a method and apparatus that can solve the above-mentioned problem.

[0028] Each Aspects and elements may relate to one of following descriptions, combination of following descriptions, or all of following descriptions, but the each Aspects and the elements are not limited to following descriptions.

[0029] Each Aspects and elements may provide solution related to one of following descriptions, combination of following descriptions, or all of following descriptions, but the each Aspects and the elements may provide solution other than the following descriptions.

[0030] For example, the following aspects needs to be supported by the 3GPP standard to make the 5G Femtocell deployment possible: ●　　Define the overall architecture and required functional and procedural impacts for supporting 5G Femtocell deployments. ●　　Define the 5G Femtocell access control mechanism based on the existing CAG (Closed Access Group) concept. ●　　Enable provisioning of subscribers allowed to access 5G Femtocells and how to manage an access control for 5G Femtocell by the CAG owner or an authorized administrator.

[0031] 5G Femtocell offers a cost-effective way to improve 5G indoor coverage, and offload macro gNB network traffic. 5G Femtocell can use higher frequency bands, allowing premises owners to deploy Femtocell on their own, and leading to efficient and effective usage of higher frequency spectrum.

[0032] A method of a User Equipment (UE) according to example aspect of this disclosure includes performing a registration procedure using a 5G Femtocell.

[0033] A method of a network node according to example aspect of this disclosure includes performing a registration procedure using a 5G Femtocell.

[0034] A method of a network node according to example aspect of this disclosure includes performing a 5G Femtocell setup procedure.

[0035] A User Equipment (UE) according to example aspect of this disclosure includes means for performing a registration procedure using a 5G Femtocell.

[0036] A network node according to example aspect of this disclosure includes means for performing a registration procedure using a 5G Femtocell.

[0037] A network node according to example aspect of this disclosure includes performing a 5G Femtocell setup procedure.

[0038] First Aspect 　　This aspect discloses an architecture and mechanisms to support the 5G Femtocell 501 in 5GS.

[0039] First example of the First Aspect 　　This example includes an architecture to support the 5G Femtocell 501 in 5GS. 　　Fig. 1 illustrates an example of an 5GS architecture that supports 5G Femtocells.

[0040] The 5G Femtocell 501 represents an 5G Femtocell in a private premise, for example, private house, office, school, park, factory, hospital, museum, stadium or etc. The 5G Femtocell 501 is connected to the SecGW 502 that is located at the PLMN. The SecGW 502 in Fig. 1 may be considered as an entity in 5G RAN node 5 of the PLMN or an entity in the Core Network 7 of the PLMN. The connection between the 5G Femtocell 501 and the SecGW 502 are security protected adapting the IPsec technology. The 5G RAN node 5 may include the 5G Femtocell 501. The SecGW 502 may be expressed as SeGW.

[0041] In one example, the 5G Femtocell 501 uses the FR2 (Frequency Range 2, 24250MHz - 52600MHz).

[0042] In another example, the 5G Femtocell 501 uses the FR1 (Frequency Range 1, 450MHz - 6000MHz). 　　In one example, the SecGW 502 is located at the 5GC (Core network 7) in the PLMN.

[0043] In one example, the SecGW 502 is located at the 5G RAN node 5 in the PLMN. 　　The SecGW 502 may be expressed by different ways, for example, N3IWF, Security gateway for Femtocell access, Security Gateway for Femtocell, etc.

[0044] The AAA Server 77 is an authentication and authorization server for the 5G Femtocell 501. The AAA Server may be located at a Credentials Holder (CH)'s network.

[0045] In a case where the UPF 72 is located at the private premise close to the 5G Femtocell 501, a connection between the 5G Femtocell 501 and the UPF 72 may be directly connected without traversing the SecGW 502. I.e., there is no IPsec tunnel for the connection between the 5G Femtocell 501 and the UPF 72.

[0046] In a case where the UPF 72 is located at the private premise close to the 5G Femtocell 501, a connection between the 5G Femtocell 501 and the UPF 72 may always be connected though the SecGW 502. I.e., there is the IPsec tunnel for the connection between the 5G Femtocell 501 and the UPF 72. For example, the user data can be monitored by the PLMN with this connection model.

[0047] The SMF 71 may be located at the private premise close to the 5G Femtocell 501 if the UPF 72 is located at the private premise. 　　The AF 201 may be located at the private premise close to the 5G Femtocell 501 if the UPF 72 is located at the private premise.

[0048] Based on the disclosed architecture in this aspect, this aspect also discloses protocol stacks between the 5G Femtocell 501 and AMF 70 and between the 5G Femtocell 501 and UPF 72.

[0049] Fig. 2 illustrates an example of a protocol stack between the 5G Femtocell 501 and the AMF 70 for an Internet Protocol IPv4 address with the NAT 503 located between the 5G Femtocell 501 and the AMF 70.

[0050] The IPsec connection is established between the 5G Femtocell 501 and the AMF 70 in order to secure control signalling in both the STCP layer and the NGAP layer. 　　The STCP connection as well as the NGAP connection are established after the IPsec layer is deployed between the 5G Femtocell 501 and the AMF 70. 　　For example, the NGAP connection is established based on the signalling diagram as disclosed by the Second example of the First Aspect.

[0051] Fig. 3 illustrates an example of a protocol stack between the 5G Femtocell 501 and the AMF 70 for an Internet Protocol IPv6 address. 　　The IPsec connection is established between the 5G Femtocell 501 and the AMF 70 in order to secure control signalling in both the STCP layer and the NGAP layer.

[0052] The STCP connection as well as the NGAP connection are established after the IPsec layer is deployed between the 5G Femtocell 501 and the AMF 70. 　　For example, the NGAP connection is established based on the signalling diagram as disclosed by the Second example of the First Aspect.

[0053] Fig. 4 illustrates an example of a protocol stack between the 5G Femtocell 501 and the UPF 72 for an Internet Protocol IPv4 address with the NAT 503 located between the 5G Femtocell 501 and the UPF 72.

[0054] The IPsec connection is established between the 5G Femtocell 501 and the UPF 72 in order to secure control signalling in both the UDP layer and the GTP-U layer.

[0055] Fig. 5 illustrates an example of a protocol stack between the 5G Femtocell 501 and the UPF 72 for an Internet Protocol IPv6 address. 　　The IPsec connection is established between the 5G Femtocell 501 and the UPF 72 in order to secure control signalling in both the UDP layer and the GTP-U layer.

[0056] Second example of the First Aspect 　　This example includes a mechanism of the initialization procedure for the 5G Femtocell 501. The initialization procedure is, for example, booting up procedure, but it can be any other procedure.

[0057] This aspect may be referred when the 5G Femtocell 501 boots up very first time, when the 5G Femtocell 501 restarts, when the system configuration of the 5G Femtocell 501 is updated.

[0058] While this example discloses a mechanism to initialize the IP layer for deploying the IPsec tunnel between the 5G Femtocell 501 and SecGW 502, the third example discloses a mechanism to initialize the NGAP layer.

[0059] Fig. 6 illustrates an example of the initialization procedure for the 5G Femtocell 501. 　　The detailed processes of the Second example of the First Aspect are described below with reference to Fig. 6.

[0060] Step 1. The 5G Femtocell 501 is ready to start the initialization procedure. For example, the 5G Femtocell 501 boots up very first time, when the 5G Femtocell 501 restarts, when the system configuration of the 5G Femtocell 501 is updated.

[0061] Step 2. The 5G Femtocell 501 sends the IKE_SA_INIT request message to the SecGW 502.

[0062] Step 3. Upon reception of the IKE_SA_INIT request message from the 5G Femtocell 501, the SecGW 502 sends the IKE_SA_INIT response message, requesting a certificate from the 5G Femtocell 501.

[0063] Step 4. Upon reception of the I IKE_SA_INIT response message from the SecGW 502, the 5G Femtocell 501 sends the IKE_AUTH request message including AUTH1 and Idi. The AUTH1 is an authentication parameter of the 5G Femtocell 501. The CSG ID is set to the Idi as the identity of the 5G Femtocell 501. The 5G Femtocell 501 also requests a certificate from the SecGW 502.

[0064] Step 5. Upon reception of the IKE_AUTH request message from the 5G Femtocell 501, 　　SecGW 502 checks the correctness of the AUTH1 received from the 5G Femtocell 501 and calculates the AUTH parameter as to set to the AUTH2.

[0065] Step 6. The SecGW 502 sends the IKE_AUTH response message to the 5G Femtocell 501 including with AUTH2 and Idi. The AUTH2 is an authentication parameter of the SecGW 502. The Idi is an identifier of the SecGW 502.

[0066] Step 7. Upon reception of the IKE_AUTH response message from the SecGW 502, the 5G Femtocell 501 checks the correctness of the AUTH2 received from the SecGW 502.

[0067] Step 8. The 5G Femtocell 501 sends another IKE_AUTH request message including Idi to perform EAP authentication. The CSG ID is set to the Idi as the identity of the 5G Femtocell 501.

[0068] Step 9. The SecGW 502 sends the Authentication Request message with an empty EAP AVP to the AAA Server 77, containing the identity received in IKE_AUTH request message received in step 8.

[0069] Step 10. The EAP-AKA-based authentication procedure continues with Step 10 in section A2 in NPL 2 take place with the following terminology replacements. ●　　H(e)NB is replaced with the 5G Femtocell 501. ●　　SeGW is replaced with the SecGW 502. ●　　AAA-Server is replaced with the AAA Server 77. ●　　HSS is replaced with the UDM 75.

[0070] Step 11. After successful EAP-AKA-based authentication procedure, the 5G Femtocell 501 performs the NG Setup procedure with the AMF 70.

[0071] Variant 1 of First example of the First Aspect 　　In a case where the 5G Femtocell 501 is deployed in the operator network (PLMN operator network) or a trusted domain of the operator network, Steps 2 to 10 may not take place.

[0072] Third example of the First Aspect 　　Fig. 7 illustrates an example of the setup procedure for the 5G Femtocell 501. 　　The detailed processes of the Third example of the First Aspect are described below with reference to Fig. 7.

[0073] Step 1. The 5G Femtocell 501 triggers the NG Setup procedure. For example, in a case where the 5G Femtocell 501 restarts or the configuration of the 5G Femtocell 501 is updated, the 5G Femtocell 501 may trigger the NG Setup procedure.

[0074] Step 2. The 5G Femtocell 501 sends an NG Setup request message to the AMF 70 including at least one of 5G Femtocell supported, CSG ID, List of supported SMF information, and List of supported UPF information. The following bullets explain each parameter in detail.

[0075] ●　　5G Femtocell supported: The 5G Femtocell supported indicates that the 5G Femtocell related features (for example, CSG handling, etc.) are supported by the 5G Femtocell 501.

[0076] The 5G Femtocell supported may have a different expression and it has a several value. For example, the 5G Femtocell supported may be called as BS type (Base Station type) and it may have one or more of the following values for example: 　　　　5G Femtocell 　　　　Open 5G Femtocell 　　　　Private 5G Femtocell 　　　　NPN 5G Femtocell 　　　　PNI-NPN 5G Femtocell 　　　　SNPN 5G Femtocell 　　　　5G Femtocell in DU for UPF direct connection 　　　　Open 5G Femtocell in DU for UPF direct connection 　　　　Private 5G Femtocell in DU for UPF direct connection 　　　　NPN 5G Femtocell in DU for UPF direct connection 　　　　PNI-NPN 5G Femtocell in DU for UPF direct connection 　　　　SNPN 5G Femtocell in DU for UPF direct connection

[0077] ●　　CSG ID: The CSG ID indicates the CSG (Closed Subscriber Group) identifier. The CSG ID may be the same as the CAG (Closed Access Group) identifier or CAG identity that is used for the Public Network Integrated NPN as defined in NPL 4.

[0078] In a case where the CSG ID is a part of the CAG ID, the following format in Fig. 8 may take.

[0079] In this format, CSG Identifier may be used as the same as the CAG identifier in the RRC protocol as well as NAS protocols. The CSG indicator field in the CAG Identifier indicates that this information is used to express the CSG Identifier as a discriminator and the value of the CSG Identifier is in the f (27 bit-length) in the CAG Identifier. The value part of the CSG Identifier can commonly be managed with the Closed Subscriber Group for EPS as defined in section 4.7 in NPL 3. In one example, Value "00000" in the CSG indicator field may be a discriminator to indicate that the CAG identifier (32 bit-length) applies to the CSG Identifier and the CSG Identifier field (27 bit-length) is considered as a value of the CSG Identifier.

[0080] In another example, Value "11111" in the CSG indicator field may be a discriminator to indicate that the CAG identifier (32 bit-length) applies to the CSG Identifier and the CSG Identifier field (27 bit-length) is considered as a value of the CSG Identifier.

[0081] In yet another example, the MSB (Most Significant Bit) of the CAG Identifier may be used to distinguish whether it is a CAG Identifier or a CSG Identifier.

[0082] ●　　List of supported SMF information: The List of supported SMF information indicates a list of SMFs that are integrated with the 5G Femtocell 501 or a list of SMFs that are located close to the 5G Femtocell 501 in the same IP domain. The List of supported SMF information may have one SMF entry or multiple SMF entries. Each entry of the SMF information may have at least the following information: 　　　　FQDN to the SMF, IP address of the SMF 　　　　Associated CSG Identifier 　　　　Supported IP version 　　　　List of associated DNN 　　　　List of associated S-NSSAI 　　　　List of associated NDD and S-NSSAI combination

[0083] ●　　List of supported UPF information: The List of supported UPF information indicates a list of UPFs that are integrated with the 5G Femtocell 501 or a list of UPFs that are located close to the 5G Femtocell 501 in the same IP domain. The List of supported UPF information may have one UPF entry or multiple UPF entries. Each entry of the UPF may have at least the following information: 　　　　FQDN to the UPF, IP address of the UPF 　　　　Associated CSG Identifier 　　　　Supported IP version 　　　　List of associated DNN 　　　　List of associated S-NSSAI 　　　　List of associated NDD and S-NSSAI combination 　　　　NAT information (the range of IP addresses the NAT uses towards the DN (e.g., public IP addresses))

[0084] In a case where the NG Setup request message includes the List of supported SMF information, the following Steps 3-a1 to 3-a3 take place.

[0085] Step 3-a1. Upon reception of the NG Setup request message, the AMF 70 sends an Nnrf_NFManagement_NFRegister message to an NRF 78 including at least one of NF type and SMF information.

[0086] The NF type indicates the Network Function type and it is set as the SMF. The SMF information is one entity of the List of supported SMF information.

[0087] In a case where the List of supported SMF information in Step 2 includes multiple entries, the AMF 70 sends the Nudm_UECM_Registration Request message to an NRF 78 multiple times to register the SMFs in the NRF 78. Alternatively, the AMF 70 may include a list of multiple SMF entities in the Nudm_UECM_Registration Request message to the NRF 78 and register them with the NRF 78 in a single interaction with the NRF 78.

[0088] Step 3-a2. Upon reception of the Nnrf_NFManagement_NFRegister message from the AMF 70, the NRF 78 registers the received SMF information to the record in the NRF 78. The CSG ID may be used by the NRF 78 or other consumer node to restrict the access with this SMF only for those of users who are accessing from the 5G Femtocell 501.

[0089] Step 3-a3. The NRF 78 sends the Nnrf_NFManagement_NFRegister response message to the AMF 70. The Nnrf_NFManagement_NFRegister response message may include a cause value indicating that the requested registration is successfully completed or not.

[0090] In a case where the NG Setup request message includes the List of supported UPF information, the following Steps 3-b1 to 3-b3 take place.

[0091] Step 3-b1. Upon reception of the NG Setup request message, the AMF 70 sends an Nnrf_NFManagement_NFRegister message to an NRF 78 including at least one of NF type and UPF information.

[0092] The NF type indicates the Network Function type and it is set as the UPF. The UPF information is one entity of the List of supported SMF information.

[0093] In a case where the List of supported UPF information in Step 2 includes multiple entries, the AMF 70 sends the Nudm_UECM_Registration Request message to an NRF 78 multiple times to register the UPFs in the NRF 78. Alternatively, the AMF 70 may include a list of multiple UPF entities in the Nudm_UECM_Registration Request message to the NRF 78 and register them with the NRF 78 in a single interaction with the NRF 78.

[0094] Step 3-b2. Upon reception of the Nnrf_NFManagement_NFRegister message from the AMF 70, the NRF 78 registers the received UPF information to the record in the NRF 78. The CSG ID may be used by the NRF 78 or other consumer node to restrict to access with this UPF only for those of users who are accessing from the 5G Femtocell 501.

[0095] Step 3-b3. The NRF 78 sends the Nnrf_NFManagement_NFRegister response message to the AMF 70. The Nnrf_NFManagement_NFRegister response message may include a cause value indicating that the requested registration is successfully completed or not.

[0096] Step 4. The AMF 70 sends the NG Setup response message to the 5G Femtocell 501 including at least one of 5G Femtocell supported, SMF registered and UPF registered.

[0097] The following bullets explain each parameter in detail. ●　　The 5G Femtocell supported: The 5G Femtocell supported indicates that the 5G Femtocell related features (for example, CSG handling, etc.) are supported by the AMF 70 and associated SMF 71, UPF 72, or other associated 5GC nodes.

[0098] ●　　SMF registered: The SMF registered indicates that the SMF entry, as indicated in the NG Setup request in Step 2, is successfully registered in the NRF 78. The SMF registered may have an associated SMF information in a case where the List of supported SMF information in the NG Setup request in Step 2 has multiple entries. This information may be set based on the received cause in Step 3-a3.

[0099] ●　　UPF registered: The UPF registered indicates that the UPF entry as indicated in the NG Setup request in Step 2 is successfully registered in the NRF 78. The UPF registered may have an associated UPF information in a case where the List of supported UPF information in the NG Setup request in Step 2 has multiple entries. This information may be set based on the received cause in Step 3-b3.

[0100] Variant 1 of Third example of the First Aspect 　　The NG Setup request message in Step 2 may be a RAN Configuration Update message or any existing NGAP message or a new NGAP message. 　　The NG Setup response message in Step 4 may be a RAN Configuration Update Acknowledge message or any existing NGAP message or a new NGAP message.

[0101] Variant 2 of Third example of the First Aspect 　　In a case where the 5G Femtocell 501 receives the AMF Configuration Update message or any other existing or a new NGAP message from the AMF 70, the 5G Femtocell 501 sends the AMF Configuration Update Acknowledge message to the AMF 70 including at least one of 5G Femtocell supported, CSG ID, List of supported SMF information, and List of supported UPF information. Refer to Step 2 for parameter details.

[0102] When the AMF 70 receives the AMF Configuration Update Acknowledge message or any other existing or a new NGAP message from the 5G Femtocell 501 including at least one of 5G Femtocell supported, CSG ID, List of supported SMF information, and List of supported UPF information, Steps 3-a1 to 3-a3 and / or Steps 3-b1 to 3-b3 take place.

[0103] Variant 3 of Third example of the First Aspect 　　One example, the CSG indicator field in the CAG Identifier in the system information (sent over the BCCH) or new indicator in the system information (sent over the BCCH) may indicate whether the 5G Femtocell 501 is an open Femtocell or a closed Femtocell.

[0104] While the open Femtocell can be accessed by any UE3s, the closed Femtocell requires a membership to access to the 5G Femtocell 501. The membership to access to the 5G Femtocell 501 may be managed in the UDM 75 as the subscriber data for the UE 3 together with the CSG ID.

[0105] One example when the UE 3 accesses to the 5G Femtocell 501 either as the open Femtocell or as the closed Femtocell, the AS layer in the UE 3 reports to the upper layer of the UE 3 as the UE 3 is accessing with either as the open Femtocell or as the closed Femtocell. When the upper layer of the UE 3 receives the report indicating Femtocell access, a display of the UE 3 may display an icon that indicate the Femtocell access. The icon that indicates the Femtocell access may be read by the user to distinguish either it is the Femtocell access or not.

[0106] In a case where the PLMN or NPN operator provides a different tariff plan for the Femtocell access (Example, any connectivity services using Femtocell are free of charge.), the icon is useful for users to know a cost of the connectivity services.

[0107] Fourth example of the First Aspect 　　This example discloses mechanisms for access control to the 5G Femtocell 501 by broadcasting 5G Femtocell related information.

[0108] The 5G Femtocell 501 for NR 　　The access control to the 5G Femtocell 501 for NR includes one or more of the following technical aspects. ●　　A 5G Femtocell 501 broadcasts a CSG support indication bit in an existing MIB or SIB. Fig. 9 illustrates an example of new additional information in the SIB2.

[0109] ●　　When the UE 3, as a 5G UE supporting a CSG features, reads the CSG support indication in a SIB or MIB, it can identify that it is the CSG cell and read the CAG ID (CAG identifier or CAG identity).

[0110] ●　　If the CAG ID is configured in the allowed CSG list in the UE 3, the UE 3 considers the cell as a suitable CSG cell for the UE 3 otherwise the cell is not suitable.

[0111] ●　　If the SIB doesn't broadcast the CSG support indication and broadcasts the CAG ID (CAG identifier or CAG identity), the UE 3 considers the cell as a CAG cell and considers the cell as valid if the CAG ID is configured in the allowed CAG list in the UE 3.

[0112] ●　　A 5G Femtocell 501 broadcasts a bit as barred in order to restrict the legacy UE camping on the 5G CSG cell. Fig. 10 illustrates an example of new additional information in the SIB1.

[0113] ●　　The UE 3, 5G UE supporting the bit for access restriction, ignores this bit.

[0114] The 5G Femtocell 501 for E-UTRA 　　The access control to the 5G Femtocell 501 for E-UTRA includes one or more of the following technical aspects.

[0115] ●　　A 5G Femtocell 501 broadcasts a 5G CSG support indication bit in an existing SIB 1 which is different than the existing CSG Support indication in SIB 1.

[0116] ●　　When the UE 3, a 5G UE supporting a CSG features, reads the 5G CSG support indication in a SIB 1, it can determine that the cell support CSG in 5GS and read the CSG ID (CSG identifier or CSG identity).

[0117] ●　　If the CSG ID is configured in the allowed CSG list in the UE 3, the UE 3 considers the cell as a suitable CSG cell for 5GS otherwise the cell is not suitable for the 5GS.

[0118] ●　　The cell can broadcast CSG ID for 5GS which is different from the CSG ID (CSG identifier or CSG identity) for EPS.

[0119] ●　　If the SIB doesn't broadcast the 5G CSG support indication and only broadcasts the CSG support indication, the UE 3 considers the cell supports CSG only in EPS. If the femto cell indicates support of 5GS and does not support CSG in the 5GS then the UE initiates attach procedure or tracking area update procedure if the CSG identity of the femto cell is in the allowed CSG list of the UE.

[0120] ●　　In one example when the UE performs manual CSG identity selection procedure, the UE shall present only those CAG identity to the user which has associated HNB name broadcasted in an existing SIB or a new SIB. the UE will ignore the CAG identities which has no associated HNB name associated with it. This is the case when the CAG identity is used to broadcasts the CSG identity.

[0121] ●　　In one example, when the UE is configured as CAG only UE, the 5GS UDM or AMF either triggers network initiated procedure (e.g. UE configuration update procedure) to send the allowed CAG identities which contains CAG identities of only PNI-NPN or send the allowed CAG identities which contains CAG identities of only PNI-NPN in the Registration accept message or any other existing NAS message. This is the case when the CAG identity is used to broadcasts the CSG identity. When the UE is configured as CAG only UE and it knows that a CAG identity is associated with femto cell (e.g., the HNB name is associated with the CAG identity) then the UE shall not use the CAG identity to select a cell.

[0122] Fifth example of the First Aspect 　　Fig. 11 illustrates an example of the Registration procedure with the 5G Femtocell 501.

[0123] This example includes a method of a User Equipment (UE). The method includes the UE for requesting access 5G Femtocell and a 5GC allows the UE to access 5G Femtocell if the UE has valid subscription for 5G Femtocell access.

[0124] The detailed processes of the Fifth example of the First Aspect are described below with reference to Fig. 11.

[0125] Step 1. The UE 3 listens to the broadcast information and decides to perform the Registration procedure with the 5G Femtocell 501.

[0126] In one example, the UE 3 listens to the broadcast information as disclosed in the Fourth example of the First Aspect and decides to perform the Registration procedure with the 5G Femtocell 501. 　　The UE 3 sends the RRC Setup Request message to the 5G Femtocell 501.

[0127] Step 2. Upon the reception of the RRC Setup Request message in Step 1, the 5G Femtocell 501 sends the RRC Setup message to the UE 3.

[0128] Step 3. The UE 3 sends the RRC Setup Complete message to the 5G Femtocell 501 including at least one of 5G CSG support indication and Dedicated NAS message. Refer to the following bullets for the 5G CSG support indication. The Dedicated NAS message includes the Registration Request message. The Registration Request message to an AMF 70 includes at least one of User ID and 5G CSG support indication.

[0129] The following bullets explain each parameter in detail. ●　　User ID: User ID (e.g., the User ID may be expressed as User Identity) may be a 5G-GUTI, SUCI or SUPI.

[0130] ●　　5G CSG support indication: The 5G CSG support indication indicates that the UE 3 supports necessary functionalities (e.g., the procedures as defined in the Aspects of this disclosure) to access the 5G Femtocell.

[0131] Step 4. Upon reception of the RRC Setup Complete message from the UE 3, the 5G Femtocell 501 sends the Initial UE message to the AMF 70 including at least one of 5G CSG support indication, 5G Femtocell supported, 5G CSG ID and NAS PDU. The NAS-PDU includes the Registration Request message that is received in the Dedicated NAS in Step 3.

[0132] The 5G CSG ID is a 5G CSG ID that the UE 3 is accessing and may be included by the 5G Femtocell 501. 　　For the 5G Femtocell supported, refer to Step 2 in Fig. 7.

[0133] Step 5. Upon reception of the Registration Request message in step 5, the AMF 70 sends an Nudm_UECM_Registration Request message to a UDM 75 including at least one of the SUPI, 5G CSG support indication and 5G CSG ID.

[0134] For example, the 5G CSG ID in Nudm_UECM_Registration Request message may be included by the AMF 70 from the 5G CSG ID that is received in the Initial UE message in Step 4.

[0135] For example, the 5G CSG ID in Nudm_UECM_Registration Request message may be included by the AMF 70 from the 5G CSG ID that is received in the NG Setup request message in Step 2 in Fig. 7.

[0136] Step 6. Upon reception of the Nudm_UECM_Registration Request message in step 5, the UDM 75 sends an Nudm_UECM_Registration Response message to the AMF 70.

[0137] Step 7. After the completion of the Nudm_UECM_Registration service in steps 5 and 6, the AMF 70 sends an Nudm_SDM_Get Request message to the UDM 75 including at least one of the SUPI, 5G CSG support indication and 5G CSG ID.

[0138] Step 8. The UDM 75 finds Subscriber data for the UE 3 and sends an Nudm_SDM_Get Response message to the AMF 70 including the Subscriber data for the UE 3. The Subscriber data may include an Allowed CSG Identifier list or the Operator CSG list. The Allowed CSG Identifier list is a list of CSG IDs that the UE 3 is allowed to access.

[0139] The Allowed CSG Identifier list may be provided to the AMF 70 in the subscriber data only if the UE 3 subscribes to one or more CSGs (Closed Service Groups).

[0140] In one example, the Allowed CSG Identifier list may be provided to the AMF 70 in the subscriber data if the UDM 75 receives the 5G CSG support indication in the Nudm_UECM_Registration Request message in Step 5 or in the Nudm_SDM_Get Request message in Step 7.

[0141] After Step 8, the AMF 70 may send the Registration Accept message to the UE 3 as a successful Registration procedure or the Registration Reject message to the UE 3 as an unsuccessful Registration procedure. 　　For the successful Registration, follows Steps 9-a1 and 9-a2, otherwise, follows Step 9-b1.

[0142] Successful Registration 　　Step 9-a1. The AMF 70 sends the Registration Accept message to the UE 3 including at least one of 5G-GUTI and Allowed CSG Identifier list or the Operator CSG list.

[0143] The AMF 70 accepts the Registration procedure from the UE 3 if the CSG ID for the 5G Femtocell 501 that the UE 3 is currently accessing with is in the Allowed CSG Identifier list or Operator CSG list that is received from the UDM 75.

[0144] The AMF 70 accepts the Registration procedure from the UE 3 if the UE 3 is accessing with non-Femtocell (for example, usual cells that PLMN operator deployed in their network).

[0145] Step 9-a2. Upon reception of the Registration Accept message, the UE 3 stores the received Allowed CSG Identifier list in the Registration Accept message in step 9-a1 into non-volatile memory in the UE 3. 　　The UE 301 sends the Registration Complete message to the AMF 70.

[0146] Unsuccessful Registration 　　Step 9-b1. The AMF 70 sends the Registration Reject message to the UE 3 including a cause.

[0147] The AMF 70 may reject the Registration procedure from the UE 3 if the CSG ID for the 5G Femtocell 501 that the UE 3 is currently accessing with is not in the Allowed CSG Identifier list that is received from the UDM 75.

[0148] The AMF 70 may reject the Registration procedure from the UE 3 if the UE 3 is accessing with the 5G Femtocell 501 but the UE 3 does not indicate the 5G CSG support indication in the Registration Request message.

[0149] The AMF 70 may include a cause in the Registration Reject with the Cause #6 - Illegal ME or another existing or a new cause value in a case where the UE 3 does not indicate the 5G CSG support indication in the Registration Request message.

[0150] The AMF 70 may include a new cause in the Registration Reject indicating that the 5G Femtocell 501 that the UE 3 is currently accessing with is not in the Allowed CSG Identifier list.

[0151] When the UE 3 receives the Registration Reject message from the AMF 70, the UE 3 may not attempt another Registration procedure with the 5G Femtocell 501 depending on the received cause value.

[0152] Variant 1 of Fifth example of the First Aspect 　　In Step 8, The UDM 75 may manage the Allowed CSG Identifier list associating with the S-NSSAI.

[0153] In one example, the S-NSSAI in the subscriber data may have associated CSG Identifiers. 　　In another example, each CSG Identifier in the Allowed CSG Identifier list may have associated S-NSSAIs in the Subscribed NSSAI.

[0154] When the AMF 70 receives the Nudm_SDM_Get Response message from the UDM 75 including the Allowed CSG Identifier list associating with the S-NSSAI. The AMF 70 may send the Registration Accept message to the UE3 only if an associated S-NSSAI with the CSG Identifier in the Allowed CSG Identifier list is included in the Allowed NSSAI or Pending NSSAI in the Registration Accept message.

[0155] Variant 2 of Fifth example of the First Aspect 　　In Step 9-a1, the UE 3 stores the received Allowed CSG Identifier list in a dedicated memory for the 5G Femtocell access in the UE 3. In this case, the UE 3 may have two Allowed CSG Identifier lists, one for the 5G Femtocell access and the other one for the HeNB (Home eNodeB) access in EPS.

[0156] With this approach, the CSG Identifier value for the 5G Femtocell access may have a different value from a CSG Identifier value for the HeNB (Home eNodeB) access in EPS.

[0157] In addition, the CAG Identifier that is used for the Public Network Integrated NPN access as defined in NPL 4 may be maintained in the UE 3 even the UE 3 moves to the EPS and an Allowed CSG Identifier list for the HeNB (Home eNodeB) access is stored when the UE 3 accesses with the EPS. I.E., the CAG Identifier for the Public Network Integrated NPN access is not overwritten by the received Allowed CSG Identifier list for the HeNB (Home eNodeB) access.

[0158] Alternatively, in Step 9-a1, the UE 3 stores the received Allowed CSG Identifier list in a common memory in the UE 3 for both the 5G Femtocell access and the HeNB (Home eNodeB) access with EPS.

[0159] With this approach, the CSG Identifier for the UE 3 have a common CSG Identifier value for the 5G Femtocell access and the HeNB (Home eNodeB) access in EPS.

[0160] In addition, the MME in the EPC may provide the CAG Identifier for the Public Network Integrated NPN access together with the Allowed CSG Identifier list for the HeNB (Home eNodeB) access in the Attach accept message or the TAU accept message or any existing NAS messages.

[0161] Variant 3 of Fifth example of the First Aspect 　　In one example, at step 3 of Fig. 11 if the 5G CSG support indication is included in the RRC Setup Complete message from the UE 3, the 5G Femtocell 501 may use the 5G CSG support indication in order to select an AMF, for example AMF 70, which supports the 5G CSG functionality.

[0162] Variant 4 of Fifth example of the First Aspect 　　In one example the operator CSG list as defined in Annex C of TS 23.122 is sent using SOR procedure. The UDM in step 3a of C.2 of TS 23.122 gets operator CSG list from the SoR in the Nsoraf_SoR_Get Response message. One receiving the operator CSG list the UDM sends to the operator CSG list in the steering of roaming information UE suing SoR procedure as defined in the Annex C of TS 23.122. In one example an entry in operator CSG list may contain CSG identity or CAG identity + PLMN ID or SNPN ID + HNB name.

[0163] Sixth example of the First Aspect 　　Fig. 12 illustrates an example of the PDU Session Establishment procedure with both the UPF 72 and the SMF 71 located at close distance to the 5G Femtocell 501. For example, both the UPF 72 and the SMF 71 are located at the same IP domain of the 5G Femtocell 501 and both the UPF 72 and the SMF 71 are reachable from any core network nodes in 5GC (Core network 7) securely using the IPsec tunnel.

[0164] In one example, only the UPF 72 is located at close distance to the 5G Femtocell 501 while the SMF 71 is located at the 5GC (Core network 7) in operator network.

[0165] For example, the UPF 72 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the 5G Femtocell 501 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect.

[0166] For example, the UPF 72 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the UPF 72 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with the UPF 72 in Fig. 6.

[0167] In another example, the SMF 71 may also be located at close distance to the 5G Femtocell 501. For example, the SMF 71 is located at the same IP domain of the 5G Femtocell 501 and the SMF 71 is reachable from any core network node in 5GC (Core network 7) securely using the IPsec tunnel.

[0168] For example, the SMF 71 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the 5G Femtocell 501 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect.

[0169] For example, the SMF 71 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the SMF 71 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with the SMF 71 in Fig. 6.

[0170] The detailed processes of the Sixth example of the First Aspect are described below with reference to Fig. 12.

[0171] Step 0. The UE 3 has been registered to the AMF 70.

[0172] Step 1. The UE 3 sends a UL NAS Transport message to the AMF 70 including at least one of PDU Session ID, 5G CSG support indication, DNN, S-NSSAI and NAS container. The NAS container includes a PDU Session Establishment Request message, Service Request message or any other NAS message with the purpose of establishing a PDU Session or with the purpose to re-use an already established PDU Session or modify the already established PDU Session.

[0173] The following bullets explain each parameter in detail. ●　　PDU Session ID: The PDU Session ID is an identifier that corresponds to an Association between the UE 3 and a Data Network 20 that provides a PDU connectivity service. ●　　5G CSG support indication: Refer to Step 3 in Fig. 11. ●　　DNN: The DNN is a Data Network Name that is equivalent to an APN in EPS. The DNN is a reference to a data network. ●　　S-NSSAI: The S-NSSAI is a Single NSSAI that indicates a network slice.

[0174] Step 2. Upon reception of the UL NAS Transport message from the UE 3, the AMF 70 performs the SMF selection based on at least one of the received 5G CSG support indication, DNN and S-NSSAI from the UE 3.

[0175] If the CSG ID in the Initial UE message from the 5G Femtocell 501 that conveys the UL NAS Transport message in Step 1 or the CSG ID that is received in the NG Setup request message as disclosed by the Third example of the First Aspect is not listed in the Allowed CSG Identifier list in the MM context for the UE 3, the AMF 70 sends back to the UE 3 the 5GSM message which was not forwarded to the SMF 71, including a 5GMM cause indicating that the CSG ID is not allowed. Otherwise, the AMF 70 sends the Nnrf_NFDiscovery_Request message to the NRF 78 including at least one of NF type, DNN, S-NSSAI, CSG ID and 5G Femtocell supported.

[0176] The following bullets explain each parameter in detail. ●　　NF type: the NF type indicates the Network Function type that the AMF 70 is selecting. In this case, the NF type is set to the SMF. ●　　DNN: Refer to Step 1. ●　　S-NSSAI: Refer to Step 1. ●　　CSG ID: The CSG ID indicates a 5G CSG ID that the UE 3 is accessing with. The AMF 70 obtains the CSG ID in the Initial UE message from the 5G Femtocell 501 when the 5G Femtocell 501 transfers the UL NAS Transport message in Step 1. ●　　5G Femtocell supported: Refer to Step 2 in Fig. 7.

[0177] Step 3. Upon reception of the Nnrf_NFDiscovery_Request message from the AMF 70, the NRF 78 performs the SMF selection based on at least one of the received DNN, S-NSSAI, CSG ID and 5G Femtocell supported indicator from the AMF 70. In one example, the NRF 78 refers to the SMF information that is provided by the AMF 70 in Step 3-a1 in Fig. 7 in the SMF selection.

[0178] The NRF 78 sends the Nnrf_NFDiscovery response message to the AMF 70 including SMF address. The SMF address may be a FQDN of the SMF 71 or the IP address of the SMF 71.

[0179] Step 4. The AMF 70 sends an Nsmf_PDUSession_CreateSMContext Request message to the SMF 71 based on the SMF address information from the NRF 78 in Step 3 including at least one of PDU Session ID, DNN, S-NSSAI, CSG ID, 5G Femtocell supported and PDU Session Establishment Request message.

[0180] Refer to Step 1 and Step 2 for parameter details. 　　In one example, the DNN, S-NSSAI, CSG ID and 5G Femtocell supported are used when the SMF 71 generates a charging ticket (known as CDR).

[0181] Step 5. Upon reception of the Nsmf_PDUSession_CreateSMContext Request message from the AMF 70, the SMF 71 sends the Nsmf_PDUSession_CreateSMContext response message to the AMF 70.

[0182] Step 6. Upon reception of the Nsmf_PDUSession_CreateSMContext Request message from the AMF 70, the SMF 71 performs the UPF selection based on at least one of the received DNN, S-NSSAI, CSG ID and 5G Femtocell supported from the AMF 70. The SMF 71 sends the Nnrf_NFDiscovery_Request message to the NRF 78 including at least one of NF type, DNN, S-NSSAI, CSG ID and 5G Femtocell supported.

[0183] The following bullets explain each parameter in detail. ●　　NF type: the NF type indicates the Network Function type that the SMF 71 is selecting. In this case, the NF type is set to the UPF. ●　　DNN: Refer to Step 1. ●　　S-NSSAI: Refer to Step 1. ●　　CSG ID: Refer to Step 2. ●　　5G Femtocell supported: Refer to Step 2 in Fig. 7.

[0184] Step 7. Upon reception of the Nnrf_NFDiscovery_Request message from the SMF 71, the NRF 78 performs the UPF selection based on at least one of the received DNN, S-NSSAI, CSG ID and 5G Femtocell supported from the AMF 70.

[0185] In one example, the NRF 78 refers to the UPF information that is provided by the AMF 70 in Step 3-b1 in Fig. 7 in the UPF selection.

[0186] The NRF 78 sends the Nnrf_NFDiscovery response message to the SMF 71 including UPF address. The UPF address may be a FQDN of the UPF 72 or the IP address of the UPF 72.

[0187] Step 8. The SMF 71 sends an N4 Session Establishment Request message to the UPF 72 based on the UPF address information from the NRF 78 in Step 7 including at least one of the PDU Session ID, DNN, S-NSSAI, CSG ID and 5G Femtocell supported.

[0188] Upon reception of the N4 Session Establishment Request message, the UPF 72 may reserve resource(s) for the PDU Session.

[0189] Step 9. After successful resource reservation for the PDU Session, the UPF 72 sends an N4 Session Establishment Response message to the SMF 71 including a UPF close to RAN chosen.

[0190] UPF close to RAN chosen indicates that the UPF 72 is chosen based on the CSG ID and the UPF 72 is located close to the 5G Femtocell 501.

[0191] Step 10. The SMF 71 sends an Namf_Communication_N1N2MessageTransfer message to the AMF 70 including at least one of PDU Session ID, N2 SM information and N1 SM container.

[0192] The N2 SM information includes the UPF close to RAN chosen. 　　The N1 SM container includes a PDU Session Establishment Accept message.

[0193] Step 11. Upon reception of the Namf_Communication_N1N2MessageTransfer message from the SMF 71, the AMF 70 sends the Downlink NAS Transport message to the 5G Femtocell 501 including the NAS PDU. The NAS PDU includes the PDU Session Establishment Accept message that is transferred by the 5G Femtocell 501 to the UE 3.

[0194] The UPF close to RAN chosen is transferred by the N2 message to the 5G Femtocell 501 when the AMF 70 sends the Downlink NAS Transport message to the UE 3.

[0195] After successful PDU Session Establishment procedure, the UE 3 communicates with the AF 201 via the UPF 72 that is located close to the 5G Femtocell 501. In one example, the AF 201 may be integrated with the 5G Femtocell 501. Another example, the AF 201 is located at the same IP domain of the 5G Femtocell 501.

[0196] The AF 201 may be called as a Service server at the Edge network. 　　The AF 201 may be called as a the MEC Service server.

[0197] In a case where the UPF 72 and AF 201 are located close to the 5G Femtocell 501, optimized user plane between the UE 3 and AF 201 may be established. The optimized user plane connection may be called as a Traffic offloading, a MEC connection or a MEC service.

[0198] Second Aspect 　　This aspect discloses an architecture and mechanisms to support the 5G SN Femtocell 501 in 5GS where the 5G SN Femtocell 501 is considered as SN (Secondary Node) in the Multi-connectivity as defined in NPL 9.

[0199] First example of the Second Aspect 　　This example includes an architecture to support the 5G SN Femtocell 501 in 5GS.

[0200] Fig. 13 illustrates an example of an 5GS architecture that supports 5G Femtocells where the 5G SN Femtocell 501 is considered as SN (Secondary Node) and the 5G MN RAN 503 is considered as MN (Master Node) in the Multi-connectivity as defined in NPL 9.

[0201] Although there is one 5G SN Femtocell 501 shown in Fig. 13 as the SN, there may be more than one 5G SN Femtocells 501 that configures the Multi-connectivity. One example, the 5G SN Femtocell 501 uses the FR2 (Frequency Range 2, 24250MHz - 52600MHz) for user data transmission while the 5G MN RAN 503 uses the FR1 (Frequency Range 1, 450MHz - 6000MHz) for both the RRC signalling transmission and user data transmission.

[0202] The 5G MN RAN 503 may be expressed as the 5G MN RAN node 503 or the 5G MN Femtocell 503. The 5G SN Femtocell 501 may provide one Femto cell. The 5G RAN node 5 may include the 5G SN Femtocell 501 and the 5G MN RAN 503.

[0203] The 5G SN Femtocell 501 represents an 5G Femtocell in a private premise, for example, private house, office, school, park, factory, hospital, museum, stadium or etc. The 5G SN Femtocell 501 is connected to the SecGW 502 that is located at the PLMN. The connection between the 5G SN Femtocell 501 and the SecGW 502 are security protected adapting the IPsec technology.

[0204] The IPsec connection between the 5G SN Femtocell 501 and the SecGW 502 may be established by the initialization procedure as disclosed in the Second example of the First Aspect except Step 11 with replacing the 5G Femtocell 501 to the 5G SN Femtocell 501 in Fig. 6.

[0205] There may be another SecGW 502 located in front of the 5G MN RAN 503. In this case, the XN interface is established between the 5G MN RAN 503 and the 5G SN Femtocell 501 after successful IPsec connection established.

[0206] The IPsec connection between the 5G SN Femtocell 501 and the SecGW 502 in front of the 5G MN RAN 503 may be established by the initialization procedure as disclosed in the Second example of the First Aspect except Step 11 with replacing the 5G Femtocell 501 to the 5G SN Femtocell 501 in Fig. 6.

[0207] The 5G SN Femtocell 501 and 5G MN RAN 503 may be located at the PLMN or NPN domain.

[0208] In this case, the SecGW 502 may not exist and the 5G SN Femtocell 501 and 5G MN RAN 503 communicate with 5GC nodes within 5GC (Core network 7) in the PLMN or NPN directly.

[0209] Second example of the Second Aspect 　　Fig. 14 illustrates an example of the setup procedure for the 5G SN Femtocell 501. 　　The detailed processes of the Second example of the Second Aspect are described below with reference to Fig. 14.

[0210] Step 1. The 5G SN Femtocell 501 triggers the XN Setup procedure. For example, in a case where the 5G SN Femtocell 501 restarts or configuration of the 5G SN Femtocell 501 is updated, the 5G SN Femtocell 501 may trigger the XN Setup procedure.

[0211] Step 2. The 5G SN Femtocell 501 sends an XN Setup request message to the 5G MN RAN 503 including at least one of 5G Femtocell supported, CSG ID, List of supported SMF information, and List of supported UPF information. Refer to Step 2 in Fig. 7 for parameter details.

[0212] Step 3-a. In a case where the XN Setup request message includes the List of supported SMF information, Steps 2, 3-a1, 3-a2, 3-a3 and 4 in Fig. 7 take place.

[0213] Step 3-b. In a case where the XN Setup request message includes the List of supported UPF information, Steps 2, 3-b1, 3-b2, 3-b3 and 4 in Fig. 7 take place.

[0214] Step 4. The 5G MN RAN 503 sends the XN Setup response message to the 5G SN Femtocell 501 including at least one of 5G Femtocell supported, SMF registered and UPF registered.

[0215] The following bullets explain each parameter in detail. ●　　The 5G Femtocell supported: Refer to Step 4 in Fig. 7.

[0216] ●　　SMF registered: The SMF registered indicates that the SMF entry as indicated in the XN Setup request in Step 2 is successfully registered in the NRF 78. The SMF registered may have an associated SMF information in a case where the List of supported SMF information in the XN Setup request in Step 2 has multiple entries. This information may be set based on the received cause in Step 3-a3 in Fig. 7.

[0217] ●　　UPF registered: The UPF registered indicates that the UPF entry as indicated in the XN Setup request in Step 2 is successfully registered in the NRF 78. The UPF registered may have an associated UPF information in a case where the List of supported UPF information in the XN Setup request in Step 2 has multiple entries. This information may be set based on the received cause in Step 3-b3 in Fig. 7.

[0218] Variant 1 of Second example of the Second Aspect 　　The XN Setup request message in Step 2 may be an NG-RAN node Configuration Update message or any other existing message or a new message between the 5G SN Femtocell 501 and the 5G MN RAN 503.

[0219] The XN Setup response message in Step 4 may be an NG-RAN node Configuration Update Acknowledge message or any other existing message or a new message between the 5G SN Femtocell 501 and the 5G MN RAN 503.

[0220] Variant 2 of Second example of the Second Aspect 　　In a case where the 5G SN Femtocell 501 receives the XN Setup request message from the 5G MN RAN 503, the 5G Femtocell SN 501 sends the XN Setup response message to the 5G MN RAN 503 including at least one of 5G Femtocell supported, CSG ID, List of supported SMF information, and List of supported UPF information. Refer to Step 2 in Fig. 7 for parameter details.

[0221] When the 5G MN RAN 503 receives the XN Setup response message from the 5G SN Femtocell 501 including at least one of 5G Femtocell supported, CSG ID, List of supported SMF information, and List of supported UPF information, Steps 3-a and / or Steps 3-b take place.

[0222] Third example of the Second Aspect 　　This example discloses mechanisms for access control to the 5G SN Femtocell 501 and / or 5G MN RAN 503 by broadcasting 5G Femtocell related information.

[0223] The 5G SN Femtocell 501 may broadcasts 5G Femtocell related information. 　　For example, the 5G SN Femtocell 501 may broadcasts 5G Femtocell related information as disclosed in the Fourth example of the First Aspect with replacing the 5G Femtocell 501 to the 5G SN Femtocell 501.

[0224] The 5G MN RAN 503 may broadcasts 5G Femtocell related information that support 5G SN Femtocell 501 on behalf of the 5G SN Femtocell 501.

[0225] For example, the 5G MN RAN 503 may broadcasts 5G Femtocell related information as disclosed in the Fourth example of the First Aspect with replacing the 5G Femtocell 501 to the 5G MN RAN 503.

[0226] Fourth example of the Second Aspect 　　This example discloses an example of the Registration procedure with the 5G SN Femtocell 501.

[0227] The Registration procedure as disclosed in the Fifth example of the First Aspect may be used with the following replacements: ●　　The 5G Femtocell 501 is replaced with the 5G MN RAN 503.

[0228] In addition, the following modifications can apply: ●　　In the Initial UE message in Step 4 in Fig. 11 from the 5G MN RAN 503, 5G Femtocell supported and 5G CSG ID are included by the 5G MN RAN 503 based on the configuration of the 5G SN Femtocell 501 that is received by the XN Setup procedure as disclosed by the Second example of the Second Aspect.

[0229] ●　　In the Registration accept message in Step 9-a1 in Fig. 11 from the AMF 70, the AMF 70 populates / includes the Allowed CSG Identifier list to the N2 message to the 5G MN RAN 503. The N2 message is not clearly illustrated in Fig. 11. The N2 message is used between the AMF 70 and the 5G MN RAN 503 to convey the Registration accept message to the UE 3 in Step 9-a1. The Allowed CSG Identifier list may be referred by the 5G MN RAN 503 when the 5G MN RAN 503 decides to configure the multi-connectivity as defined in NPL 9.

[0230] For example, if a CSG ID that is supported by the 5G SN Femtocell 501 is in the Allowed CSG Identifier list for the UE 3, the 5G MN RAN 503 decides to configure the multi-connectivity for the UE 3.

[0231] For example, if a CSG ID that is supported by the 5G SN Femtocell 501 is not in the Allowed CSG Identifier list for the UE 3, the 5G MN RAN 503 decides not to configure the multi-connectivity for the UE 3.

[0232] In one example, the Allowed CSG Identifier list may be defined within the existing NGAP parameter. For example, the Allowed CSG Identifier list may be defined in the Mobility restriction list as defined in NPL 10.

[0233] In one example, the N2 message is the Initial Context setup request message, Downlink NAS Transport message, Reroute NAS Request message, Handover Request message, other existing NGAP message or new NGAP message.

[0234] Fifth example of the Second Aspect 　　Fig. 15 illustrates an example of the PDU Session Establishment procedure with both the UPF 72 and the SMF 71 located at close distance to the 5G SN Femtocell 501. For example, both the UPF 72 and the SMF 71 are located at the same IP domain of the 5G SN Femtocell 501 and both the UPF 72 and the SMF 71 are reachable from any core network nodes in 5GC (Core network 7) securely using the IPsec tunnel.

[0235] In one example, only the UPF 72 is located at close distance to the 5G SN Femtocell 501 while the SMF 71 is located at the 5GC (Core network 7) in operator network.

[0236] For example, the UPF 72 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the 5G SN Femtocell 501 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with 5G SN Femtocell 501 in Fig. 6.

[0237] For example, the UPF 72 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the UPF 72 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with the UPF 72 in Fig. 6.

[0238] In one example, the SMF 71 may also be located at close to the 5G SN Femtocell 501. For example, the SMF 71 is located at the same IP domain of the 5G SN Femtocell 501 and the SMF 71 is reachable from any core network nodes in 5GC (Core network 7) securely using the IPsec tunnel.

[0239] For example, the SMF 71 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the 5G SN Femtocell 501 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with the 5G SN Femtocell 501 in Fig. 6.

[0240] For example, the SMF 71 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the SMF 71 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with the SMF 71 in Fig. 6.

[0241] In one example, the 5G MN RAN 502 and the 5G SN Femtocell 501 are located at the same IP domain. 　　In another example, the 5G MN RAN 502 and the 5G SN Femtocell 501 are not located at the same IP domain.

[0242] The detailed processes of the Fifth example of the Second Aspect are described below with reference to Fig. 15.

[0243] Step 0. The UE 3 has been registered to the AMF 70.

[0244] Step 1. The UE 3 sends a UL NAS Transport message to the AMF 70 via the 5G MN RAN 503 including at least one of PDU Session ID, 5G CSG support indication, DNN, S-NSSAI and NAS container. Refer to Step 1 in Fig. 12 for parameter details.

[0245] Steps 2 to 3. Steps 2 to 3 in Fig. 12 take place with replacing the 5G Femtocell 501 with the 5G MN RAN 503.

[0246] Step 4. The AMF 70 sends an Nsmf_PDUSession_CreateSMContext Request message to the SMF 71 based on the SMF address information from the NRF 78 in Step 3 in Fig. 12 including at least one of PDU Session ID, DNN, S-NSSAI, CSG ID, 5G Femtocell supported, Allowed CSG Identifier list and PDU Session Establishment Request message.

[0247] Refer to Step 1 and Step 2 in Fig. 7 for parameter details. 　　The Allowed CSG Identifier list is a list of CSG ID that the UE 3 is allowed to access. The AMF 70 may populate / include the Allowed CSG Identifier list if the AMF 70 stores it in the MM context for the UE 3.

[0248] The AMF 70 may have obtained the Allowed CSG Identifier list for the UE 3 during the Registration procedure as disclosed by the Fifth example of the First Aspect.

[0249] In one example, the DNN, S-NSSAI, CSG ID and 5G Femtocell supported are used when the SMF 71 generates a charging ticket (as known as CDR).

[0250] Step 5. If the SMF 71 does not have Session Management Subscription data for the UE 3, the SMF 71 may send the Nudm_SDM_Get message to the UDM 75 including at least one of SUPI, DNN, S-NSSAI, CSG ID and 5G Femtocell supported. Refer to Step 1 and Step 2 in Fig. 7 for parameter details.

[0251] Step 6. Upon reception of the Nudm_SDM_Get message from the SMF 71, the UDM 75 sends the Nudm_SDM_Get response message to the SMF 71 including the Session Management Subscription data. The Session Management Subscription data may include the Allowed CSG Identifier list for the UE 3.

[0252] Step 7. Steps 5 to 9 in Fig. 12 take place with replacing the 5G Femtocell 501 with the 5G MN RAN 503.

[0253] Step 8. The SMF 71 sends an Namf_Communication_N1N2MessageTransfer message to the AMF 70 including at least one of PDU Session ID, N2 SM information and N1 SM container.

[0254] The N1 SM container includes a PDU Session Establishment Accept message. 　　The N2 SM information includes the Allowed CSG Identifier list.

[0255] Step 9. Upon reception of the Namf_Communication_N1N2MessageTransfer message from the SMF 71, the AMF 70 sends the Downlink NAS Transport message to the 5G MN RAN 503 including the Allowed CSG Identifier list and the NAS PDU. The NAS PDU includes the PDU Session Establishment Accept message that is transferred by the 5G MN RAN 503 to the UE 3.

[0256] The Allowed CSG Identifier list that is received by 5G MN RAN 503 in the Downlink NAS Transport message may be considered by the 5G MN RAN 503 when the 5G MN RAN 503 decides to configure the multi-connectivity as defined in NPL 9.

[0257] For example, if a CSG ID that is supported by the 5G SN Femtocell 501 is in the Allowed CSG Identifier list for the UE 3, the 5G MN RAN 503 decides to configure the multi-connectivity for the UE 3.

[0258] For example, if a CSG ID that is supported by the 5G SN Femtocell 501 is not in the Allowed CSG Identifier list for the UE 3, the 5G MN RAN 503 decides not to configure the multi-connectivity for the UE 3.

[0259] In one example, the Allowed CSG Identifier list may be defined within the existing NGAP parameter. For example, the Allowed CSG Identifier list may be defined in the Mobility restriction list as defined in NPL 10.

[0260] After successful PDU Session Establishment procedure, the UE 3 communicates with the AF 201 via the UPF 72 that may be located close to the 5G MN RAN 503 or the 5G SN Femtocell 501. In one example, the AF 201 may be integrated with the 5G MN RAN 503 or the 5G SN Femtocell 501. Another example, the AF 201 is located at the same IP domain of the 5G MN RAN 503 or the 5G SN Femtocell 501.

[0261] The AF 201 may be called as a Service server at the Edge network. 　　The AF 201 may be called as a the MEC Service server.

[0262] Variant 1 of Fifth example of the Second Aspect 　　After successful PDU Session Establishment procedure, 5G MN RAN 503 may initiate the Secondary Node Addition procedure with the 5G SN Femtocell 501 as described in NPL 9. For example, whether the 5G MN RAN 503 initiate the Secondary Node Addition procedure with the 5G SN Femtocell 501 or not is decided based on the descriptions in Step 9.

[0263] In a case where the UPF 72 and AF 201 are located close to the 5G SN Femtocell 501, optimized user plane between the UE 3 and AF 201 may be established. The optimized user plane connection may be called as a Traffic offloading, a MEC connection or a MEC service.

[0264] Third Aspect 　　This Aspect includes an architecture to support the 5G Femtocell 501 in 5GS where the 5G Femtocell 501 is considered as DU (Distributed Unit) 61.

[0265] First example of the Third Aspect 　　This aspect discloses an architecture and mechanisms to support the 5G DU Femtocell 501 in 5GS where the 5G DU Femtocell 501 is considered as DU (Distributed Unit) 61.

[0266] Fig. 16 illustrates an example of an 5GS architecture that supports 5G Femtocells where the 5G DU Femtocell 501 is considered as a DU 61 and the 5G CU Femtocell 503 is considered as a CU 62. The 5G CU Femtocell 503 may be expressed as the 5G CU RAN node 503 or the 5G CU RAN 503. The 5G RAN node 5 and / or the 5G Femtocell may include the 5G DU Femtocell 501 and the 5G CU Femtocell 503.

[0267] Although there is one 5G DU Femtocell 501 shown in Fig. 16 as the DU 61, there may be more than one 5G DU Femtocells 501 deployed in the Private premise, PLMN or NPN. The UE 3 chooses one 5G DU Femtocell 501 to access to the AF 201 in the external network.

[0268] One example, the 5G DU Femtocell 501 uses the FR2 (Frequency Range 2, 24250MHz - 52600MHz). 　　Another example, the 5G DU Femtocell 501 uses the FR1 (Frequency Range 1, 450MHz - 6000MHz).

[0269] The 5G DU Femtocell 501 represents an 5G Femtocell in a private premise, for example, private house, office, school, park, factory, hospital, museum, stadium or etc. The 5G DU Femtocell 501 is connected to the SecGW 502 that is located at the PLMN. The connection between the 5G DU Femtocell 501 and the SecGW 502 are security protected adapting the IPsec technology.

[0270] The IPsec connection between the 5G DU Femtocell 501 and the SecGW 502 may be established by the initialization procedure as disclosed in the Second example of the First Aspect except Step 11 with replacing the 5G Femtocell 501 to the 5G DU Femtocell 501 in Fig. 6.

[0271] There may be another SecGW 502 located in front of the 5G CU Femtocell 503. In this case, the F1 interface is established between the 5G CU Femtocell 503 and the 5G DU Femtocell 501 after successful IPsec connection established.

[0272] The IPsec connection between the 5G DU Femtocell 501 and the SecGW 502 in front of the 5G CU Femtocell 503 may be established by the initialization procedure as disclosed in the Second example of the First Aspect except Step 11 with replacing the 5G Femtocell 501 to the 5G DU Femtocell 501 in Fig. 6.

[0273] The 5G DU Femtocell 501 and 5G CU Femtocell 503 may be located at the PLMN or NPN domain.

[0274] In this case, the SecGW 502 may not exist and the 5G DU Femtocell 501 and 5G CU Femtocell 503 communicate with 5GC nodes within 5GC (Core network 7) in the PLMN or NPN directly.

[0275] Second example of the Third Aspect 　　Fig. 17 illustrates an example of the setup procedure for the 5G DU Femtocell 501. 　　The detailed processes of the Second example of the Third Aspect are described below with reference to Fig. 17.

[0276] Step 1. The 5G DU Femtocell 501 triggers the F1 Setup procedure. For example, in a case where the 5G DU Femtocell 501 restarts or configuration of the 5G DU Femtocell 501 is updated, the 5G DU Femtocell 501 may trigger the F1 Setup procedure.

[0277] Step 2. The 5G DU Femtocell 501 sends an F1 Setup request message to the 5G CU Femtocell 503 including at least one of 5G Femtocell supported, CSG ID, List of supported SMF information, List of supported UPF information and List of associated 5G CU UP information. Refer to Step 2 in Fig. 7 for parameter details.

[0278] The List of associated 5G CU UP information is a set of 5G CU UPs that are associated with the 5G CU Femtocell 503. The 5G CU Femtocell 503 stores the List of associated 5G CU UP information per 5G DU Femtocell 501 basis.

[0279] A 5G CU UP in the set of 5G CU UPs may be located close to the 5G CU Femtocell 503. 　　A 5G CU UP in the set of 5G CU UPs may be integrated with the 5G CU Femtocell 503.

[0280] The set of 5G CU UPs may be associated with a UPF 72 or a set of UPFs 72 that are listed in the List of supported UPF information. 　　A 5G CU UP in the set of 5G CU UPs may be located close to a UPF 72 or a set of UPFs that are listed in the List of supported UPF information.

[0281] A 5G CU UP in the set of 5G CU UPs may be integrated with a UPF 72 or a set of UPFs 72 that are listed in the List of supported UPF information. 　　A 5G CU UP may be chosen by the 5G CU Femtocell 503 when the 5G CU Femtocell 503 establishes user plane resources with a UPF 72 that is listed in the List of supported UPF information in Step 2.

[0282] In this case, the user plane connection between the UE 3 and the AF 201 via the UPF 72 is optimized and may provide low latency communication because of a short path connection.

[0283] Step 3-a. In a case where the F1 Setup request message includes the List of supported SMF information, Steps 2, 3-a1, 3-a2, 3-a3 and 4 in Fig. 7 take place.

[0284] Step 3-b. In a case where the F1 Setup request message includes the List of supported UPF information, Steps 2, 3-b1, 3-b2, 3-b3 and 4 in Fig. 7 take place.

[0285] Step 4. The 5G CU Femtocell 503 sends the F1 Setup response message to the 5G DU Femtocell 501 including at least one of 5G Femtocell supported, SMF registered and UPF registered.

[0286] The following bullets explain each parameter in detail. ●　　The 5G Femtocell supported: Refer to Step 4 in Fig. 7.

[0287] ●　　SMF registered: The SMF registered indicates that the SMF entry as indicated in the F1 Setup request in Step 2 is successfully registered in the NRF 78. The SMF registered may have an associated SMF information in a case where the List of supported SMF information in the F1 Setup request in Step 2 has multiple entries. This information may be set based on the received cause in Step 3-a3 in Fig. 7.

[0288] ●　　UPF registered: The UPF registered indicates that the UPF entry as indicated in the F1 Setup request in Step 2 is successfully registered in the NRF 78. The UPF registered may have an associated UPF information in a case where the List of supported UPF information in the F1 Setup request in Step 2 has multiple entries. This information may be set based on the received cause in Step 3-b3 in Fig. 7.

[0289] Variant 1 of Second example of the Second Aspect 　　The F1 Setup request message in Step 2 may be an GNB-DU Configuration Update message or any other existing or a new message between the 5G DU Femtocell 501 and the 5G CU Femtocell 503.

[0290] The F1 Setup response message in Step 4 may be an GNB-DU Configuration Update Acknowledge message or any other existing or a new message between the 5G DU Femtocell 501 and the 5G CU Femtocell 503.

[0291] Variant 2 of Second example of the Second Aspect 　　In a case where the 5G DU Femtocell 501 receives the GNB-CU Configuration Update message from the 5G CU Femtocell 503, the 5G Femtocell DU 501 sends the GNB-CU Configuration Update Acknowledge message to the 5G CU Femtocell 503 including at least one of 5G Femtocell supported, CSG ID, List of supported SMF information, and List of supported UPF information. Refer to Step 2 in Fig. 7 for parameter details.

[0292] When the 5G CU Femtocell 503 receives the GNB-CU Configuration Update Acknowledge message from the 5G DU Femtocell 501 including at least one of 5G Femtocell supported, CSG ID, List of supported SMF information, and List of supported UPF information, Steps 3-a and / or Steps 3-b take place.

[0293] Third example of the Third Aspect 　　This example discloses mechanisms for access control to the 5G DU Femtocell 501 broadcasting 5G Femtocell related information.

[0294] The 5G DU 501 may broadcasts 5G Femtocell related information. 　　For example, the 5G DU Femtocell 501 may broadcast 5G Femtocell related information as disclosed in the Fourth example of the First Aspect with replacing the 5G Femtocell 501 to the 5G DU Femtocell 501.

[0295] Fourth example of the Third Aspect 　　This example discloses an example of the Registration procedure with the 5G DU Femtocell 501.

[0296] This example includes a method of a User Equipment (UE). The method includes the UE for requesting access 5G Femtocell and a 5GC allows the UE to access 5G Femtocell if the UE has valid subscription for 5G Femtocell access.

[0297] The detailed processes of the Fourth example of the Third Aspect are described below with reference to Fig. 18.

[0298] Step 1. The UE 3 listens to the broadcasting information and decides to perform the Registration procedure with the 5G DU Femtocell 501.

[0299] In one example, the UE 3 listens to the broadcasting information as disclosed in the Third example of the Third Aspect and decides to perform the Registration procedure with the 5G Femtocell DU 501. 　　The UE 3 sends the RRC Setup Request message to the 5G DU Femtocell 501.

[0300] Step 2. Upon the reception of the RRC Setup Request message in Step 1, the 5G DU Femtocell 501 sends the RRC Setup request message to the UE 3.

[0301] Step 3. The UE 3 sends the RRC Setup Complete message to the 5G DU Femtocell 501 including at least one of 5G CSG support indication and Dedicated NAS message. Refer to Step 3 in the Fifth example of the First Aspect for parameter details.

[0302] Step 4. Upon reception of the RRC Setup Complete message from the UE 3, the 5G DU Femtocell 501 sends the Initial UE RRC message to the 5G CU Femtocell 503 including at least one of 5G CSG support indication, 5G Femtocell supported, 5G CSG ID and NAS PDU. Refer to Step 4 in the Fifth example of the First Aspect for parameter details.

[0303] Upon reception of the Initial UE RRC message from the 5G DU Femtocell 501, the 5G CU Femtocell 503 sends the Initial UE message to the AMF 70 including at least one of 5G CSG support indication, 5G Femtocell supported, 5G CSG ID and NAS PDU. The NAS-PDU includes the Registration Request message that is received in the Dedicated NAS in Step 3.

[0304] The 5G CSG ID is a 5G CSG ID that the UE 3 is accessing and may be included by the 5G DU Femtocell 501. 　　For the 5G Femtocell supported, refer to Step 2 in Fig. 7.

[0305] Step 5. Steps 4 to 8 in Fig. 11 take place with replacing the 5G Femtocell 501 with the 5G DU Femtocell 501 and the 5G CU Femtocell 503.

[0306] After Step 5, the AMF 70 may send the Registration Accept message to the UE 3 as a successful Registration procedure or the Registration Reject message to the UE 3 as an unsuccessful Registration procedure. 　　For the successful Registration, follows Steps 6-a1 to 6-a4, otherwise, follows Step 6-b1.

[0307] Successful Registration 　　Step 6-a1. The AMF 70 sends the N2 message to the 5G CU Femtocell 503 including at least one of Allowed CSG Identifier list and NAS PDU. The NAS PDU includes the Registration Accept message. Further the Registration Accept message to the UE 3 including at least one of 5G-GUTI and Allowed CSG Identifier list.

[0308] The AMF 70 accepts the Registration procedure from the UE 3 if the CSG ID for the 5G DU Femtocell 501 that the UE 3 is currently accessing with is in the Allowed CSG Identifier list that is received from the UDM 75.

[0309] The AMF 70 accepts the Registration procedure from the UE 3 if the UE 3 is accessing with non-Femtocell (for example, usual cells that PLMN operator deployed in their network).

[0310] In one example, the N2 message may be DOWNLINK NAS TRANSPORT message, PDU SESSION RESOURCE SETUP REQUEST message, PDU SESSION RESOURCE MODIFY REQUEST message, INITIAL CONTEXT SETUP REQUEST message, UE CONTEXT MODIFICATION REQUEST message, any existing NGAP message or new NGAP message.

[0311] Step 6-a2. Upon reception of the N2 message from the AMF 70, The 5G CU Femtocell 503 sends the DL RRC MESSAGE TRANSFER message to the 5G DU Femtocell 501 including at least one of Allowed CSG Identifier list and RRC-Container. The RRC-Container includes the Registration Accept message. Further the Registration Accept message to the UE 3 including at least one of 5G-GUTI and Allowed CSG Identifier list. The 5G DU Femtocell 501 stores the received Allowed CSG Identifier list.

[0312] Step 6-a3. Upon reception of the DL RRC MESSAGE TRANSFER message from the 5G CU Femtocell 503, the 5G DU Femtocell 501 sends the DL information transfer message to the UE 3 including Dedicated NAS message. The Dedicated NAS message includes the Registration Accept message. Further the Registration Accept message to the UE 3 including at least one of 5G-GUTI and Allowed CSG Identifier list.

[0313] Step 6-a4. Upon reception of the Registration Accept message, the UE 3 stores the received Allowed CSG Identifier list in the Registration Accept message in step 6-a3 into non-volatile memory in the UE 3. 　　The UE 301 sends the Registration Complete message to the AMF 70.

[0314] Unsuccessful Registration 　　Step 6-b1. Refer to Step 9-b1 in Fig. 11.

[0315] Fifth example of the Third Aspect 　　Fig. 19 illustrates an example of the PDU Session Establishment procedure with both the UPF 72 and the SMF 71 located at close distance to the 5G DU Femtocell 501. For example, both the UPF 72 and the SMF 71 are located at the same IP domain of the 5G DU Femtocell 501 and both the UPF 72 and the SMF 71 are reachable from any core network nodes in 5GC (Core network 7) securely using the IPsec tunnel.

[0316] In one example, only the UPF 72 is located at close distance to the 5G DU Femtocell 501 while the SMF 71 is located at the 5GC (Core network 7) in operator network.

[0317] For example, the UPF 72 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the 5G DU Femtocell 501 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with the 5G DU Femtocell 501 in Fig. 6.

[0318] For example, the UPF 72 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the UPF 72 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with the UPF 72 in Fig. 6.

[0319] In one example, the SMF 71 may also be located at close to the 5G DU Femtocell 501. For example, the SMF 71 is located at the same IP domain of the 5G DU Femtocell 501 and the SMF 71 is reachable from any core network nodes in 5GC (Core network 7) securely using the IPsec tunnel.

[0320] For example, the SMF 71 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the 5G DU Femtocell 501 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with the 5G DU Femtocell 501 in Fig. 6.

[0321] For example, the SMF 71 may be securely reachable from the 5GC (Core network 7) using the IPsec tunnel established between the SMF 71 and the SecGW 502 by the procedure as disclosed by the Second example of the First Aspect with replacing the 5G Femtocell 501 with the SMF 71 in Fig. 6.

[0322] The detailed processes of the Fifth example of the Third Aspect are described below with reference to Fig. 19.

[0323] Step 1. Steps 0 to 10 in Fig. 12 take place with replacing the 5G Femtocell 501 with the 5G DU Femtocell 501 and the 5G CU Femtocell 503.

[0324] Step 2. The AMF 70 sends the PDU SESSION RESOURCE SETUP REQUEST message to the 5G CU Femtocell 503 including at least one of Allowed CSG Identifier list, UPF close to RAN chosen and NAS PDU. The NAS PDU includes the PDU Session Establishment accept message. Further the PDU Session Establishment accept message to the UE 3 including the Allowed CSG Identifier list.

[0325] Step 3. Upon reception of the PDU SESSION RESOURCE SETUP REQUEST message from the AMF 70, The 5G CU Femtocell 503 selects the 5G CU UP and 5G CU UP resources close to the 5G DU Femtocell 501 if the close to RAN chosen is indicated.

[0326] Alternatively, the 5G CU Femtocell 503 selects the 5G CU UP and 5G CU UP resources close to the 5G DU Femtocell 501 if the PDU Session Resource Setup Request Transfer in the PDU SESSION RESOURCE SETUP REQUEST message includes the UPF endpoint information that is close to the 5G DU Femtocell 501.

[0327] Step 4. After successful 5G CU UP selection and 5G CU UP resource reservation, the 5G CU Femtocell 503 sends the DL RRC MESSAGE TRANSFER message to the 5G DU Femtocell 501 including at least one of Allowed CSG Identifier list, UPF close to RAN chosen and RRC-Container. The RRC-Container includes the Session Establishment accept message.

[0328] Step 5. Upon reception of the DL RRC MESSAGE TRANSFER message from the 5G CU Femtocell 503, the 5G DU Femtocell 501 sends the DL information transfer message to the UE 3 including Dedicated NAS message. The Dedicated NAS message includes the Session Establishment accept message.

[0329] System overview 　　Fig. 20 schematically illustrates an example of a telecommunication system 1 for a mobile (cellular or wireless) to which the above aspects are applicable.

[0330] The telecommunication system 1 represents a system overview in which an end-to-end communication is possible. For example, UE 3 (or user equipment, 'mobile device' 3) communicates with other UEs 3 or service servers in the data network 20 via respective (R)AN nodes 5 and a core network 7.

[0331] The (R)AN node 5 supports any radio accesses including a 5G radio access technology (RAT), an E-UTRA radio access technology, a beyond 5G RAT, a 6G RAT and non-3GPP RAT including wireless local area network (WLAN) technology as defined by the Institute of Electrical and Electronics Engineers (IEEE).

[0332] The (R)AN node 5 may split into a Radio Unit (RU), Distributed Unit (DU) and Centralized Unit (CU). In some aspects, each of the units may be connected to each other and structure the (R)AN node 5 by adopting an architecture as defined by the Open RAN (O-RAN) Alliance, where the units above are referred to as O-RU, O-DU and O-CU respectively.

[0333] The (R)AN node 5 may be split into control plane function and user plane function. Further, multiple user plane functions can be allocated to support a communication. In some aspects, user traffic may be distributed to multiple user plane functions and user traffic over each user plane functions are aggregated in both the UE 3 and the (R)AN node 5. This split architecture may be called as 'dual connectivity' or 'Multi connectivity'.

[0334] The (R)AN node 5 can also support a communication using the satellite access. In some aspects, the (R)AN node 5 may support a satellite access and a terrestrial access.

[0335] In addition, the (R)AN node 5 can also be referred as an access node for a non-wireless access. The non-wireless access includes a fixed line access as defined by the Broadband Forum (BBF) and an optical access as defined by the Innovative Optical and Wireless Network (IOWN).

[0336] The core network 7 may include logical nodes (or 'functions') for supporting a communication in the telecommunication system 1. For example, the core network 7 may be 5G Core Network (5GC) that includes, amongst other functions, control plane functions and user plane functions. Each function in logical nodes can be considered as a network function. The network function may be provided to another node by adapting the Service Based Architecture (SBA).

[0337] A Network Function can be deployed as distributed, redundant, stateless, and scalable that provides the services from several locations and several execution instances in each location by adapting the network virtualization technology as defined by the European Telecommunications Standards Institute, Network Functions Virtualization (ETSI NFV).

[0338] The core network 7 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0339] As is well known, a UE 3 may enter and leave the areas (i.e., radio cells) served by the (R)AN node 5 as the UE 3 is moving around in the geographical area covered by the telecommunication system 1. In order to keep track of the UE 3 and to facilitate movement between the different (R)AN nodes 5, the core network 7 comprises at least one access and mobility management function (AMF) 70. The AMF 70 is in communication with the (R)AN node 5 coupled to the core network 7. In some core networks, a mobility management entity (MME) or a mobility management node for beyond 5G or a mobility management node for 6G may be used instead of the AMF 70.

[0340] The core network 7 also includes, amongst others, a Session Management Function (SMF) 71, a User Plane Function (UPF) 72, a Policy Control Function (PCF) 73, a Network Data Analytics Function (NWDAF) 74, a Unified Data Management (UDM) 75, a Network Slice Selection Function (NSSF) 76, an AAA Server 77, a Network Repository Function (NRF) 78. When the UE 3 is roaming to a visited Public Land Mobile Network (VPLMN), a home Public Land Mobile Network (HPLMN) of the UE 3 provides the UDM 75 and at least some of the functionalities of the SMF 71, UPF 72, PCF 73 and the AAA Server 77 for the roaming-out UE 3.

[0341] The UE 3 and a respective serving (R)AN node 5 are connected via an appropriate air interface (for example the so-called "Uu" interface and / or the like). Neighboring (R)AN node 5 are connected to each other via an appropriate (R)AN node 5 to (R)AN node interface (such as the so-called "Xn" interface and / or the like). Each (R)AN node 5 is also connected to nodes in the core network 7 (such as the so-called core network nodes) via an appropriate interface (such as the so-called "N2" / "N3" interface(s) and / or the like). From the core network 7, connection to a data network 20 is also provided. The data network 20 can be an internet, a public network, an external network, a private network or an internal network of the PLMN. In a case where the data network 20 is provided by a PLMN operator or Mobile Virtual Network Operator (MVNO), the IP Multimedia Subsystem (IMS) service may be provided by that data network 20. The UE 3 can be connected to the data network 20 using IPv4, IPv6, IPv4v6, Ethernet or unstructured data type. The data network may include an Application Function (AF) 201.

[0342] The "Uu" interface may include a Control plane of Uu interface and User plane of Uu interface.

[0343] The User plane of Uu interface is responsible to convey user traffic between the UE 3 and a serving (R)AN node 5. The User plane of Uu interface may have a layered structure with SDAP, PDCP, RLC and MAC sublayer over the physical connection (i.e., PHY sublayer).

[0344] The Control plane of Uu interface is responsible to establish, modify and release a connection between the UE 3 and a serving (R)AN node 5. The Control plane of Uu interface may have a layered structure with RRC, PDCP, RLC and MAC sublayers over the physical connection.

[0345] For example, the following messages are communicated over the RRC layer to support AS signaling.

[0346] ●　　RRC Setup Request message: This message is sent from the UE 3 to the (R)AN node 5. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be included together in the RRC Setup Request message. 　　　　establishmentCause and ue-Identity. The ue-Identity may have a value of ng-5G-S-TMSI-Part1 or randomValue.

[0347] ●　　RRC Setup message: This message is sent from the (R)AN node 5 to the UE 3. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be included together in the RRC Setup message. 　　　　masterCellGroup and radioBearerConfig

[0348] ●　　RRC setup complete message: This message is sent from the UE 3 to the (R)AN node 5. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be included together in the RRC setup complete message. 　　　　guami-Type, iab-NodeIndication, idleMeasAvailable, ue-MeasurementsAvailable, mobilityState, ng-5G-S-TMSI-Part2, registeredAMF, selectedPLMN-Identity, s-NSSAI-List, onboardingRequest

[0349] The UE 3 and the AMF 70 are connected via an appropriate interface (for example the so-called N1 interface and / or the like). The N1 interface is responsible to provide a communication between the UE 3 and the AMF 70 to support NAS signaling. The N1 interface may be established over a 3GPP access and over a non-3GPP access. For example, the following messages are communicated over the N1 interface.

[0350] ●　　registration request message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters that are disclosed by Aspects in this disclosure, 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.

[0351] ●　　registration accept message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters that are disclosed by Aspects in this disclosure, 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 5G-S-TMSI configuration, Negotiated WUS assistance information, Negotiated NB-N1 mode DRX parameters and Extended rejected NSSAI.

[0352] ●　　Registration Complete message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be included together in the Registration Complete message. 　　　　SOR transparent container.

[0353] ●　　Authentication Request message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters that are disclosed by Aspects in this disclosure, 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.

[0354] ●　　Authentication Response message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be populated together in the Authentication Response message. 　　　　Authentication response message identity, Authentication response parameter and EAP message.

[0355] ●　　Authentication Result message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be populated together in the Authentication Result message. 　　　　ngKSI, EAP message and ABBA.

[0356] ●　　Authentication Failure message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be populated together in the Authentication Failure message. 　　　　Authentication failure message identity, 5GMM cause and Authentication failure parameter.

[0357] ●　　Authentication Reject message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be populated together in the Authentication Reject message. 　　　　EAP message.

[0358] ●　　Service Request message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be populated 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.

[0359] ●　　Service Accept message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be populated together in the Service Accept message. 　　　　PDU session status, PDU session reactivation result, PDU session reactivation result error cause, EAP message and T3448 value.

[0360] ●　　Service Reject message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be populated together in the Service Reject message. 　　　　5GMM cause, PDU session status, T3346 value, EAP message, T3448 value and CAG information list.

[0361] ●　　Configuration Update Command message: This message is sent from the AMF 70 to the UE 3. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be populated 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, T3447 value, CAG information list, UE radio capability ID, UE radio capability ID deletion indication, 5GS registration result, Truncated 5G-S-TMSI configuration, Additional configuration indication and Extended rejected NSSAI.

[0362] ●　　Configuration Update Complete message: This message is sent from the UE 3 to the AMF 70. In addition to the parameters that are disclosed by Aspects in this disclosure, following parameters may be populated together in the Configuration Update Complete message. 　　　　Configuration update complete message identity.

[0363] User equipment (UE) 　　Fig. 21 is an example of a block diagram illustrating the main components of the UE 3 (mobile device 3). As shown, the UE 3 includes a transceiver circuit 31 which is operable to transmit signals to and to receive signals from the connected node(s) via one or more antennas 32. Further, the UE 3 may include a user interface 34 for inputting information from outside or outputting information to outside. Although not necessarily shown in the Figure, the UE 3 may have all the usual functionality of a conventional mobile device and this may be provided by any one or any combination of hardware, software and firmware, as appropriate. Software may be pre-installed in the memory and / or may be downloaded via the telecommunication network or from a removable data storage device (RMD), for example. A controller 33 controls the operation of the UE 3 in accordance with software stored in a memory 36. The software includes, among other things, an operating system 361 and a communications control module 362 having at least a transceiver control module 3621. The communications control module 362 (using its transceiver control module 3621) is responsible for handling (generating / sending / receiving) signalling and uplink / downlink data packets between the UE 3 and other nodes, such as the (R)AN node 5 and the AMF 70. Such signalling may include, for example, appropriately formatted signalling messages (e.g. a registration request message and associated response messages) relating to access and mobility management procedures (for the UE 3). The controller 33 interworks with one or more Universal Subscriber Identity Module (USIM) 35. If there are multiple USIMs 35 equipped, the controller 33 may activate only one USIM 35 or may activate multiple USIMs 35 at the same time.

[0364] The UE 3 may, for example, support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0365] The UE 3 may, for example, be an item of equipment for production or manufacture and / or an item of energy related machinery (for example equipment or machinery such as: boilers; engines; turbines; solar panels; wind turbines; hydroelectric generators; thermal power generators; nuclear electricity generators; batteries; nuclear systems and / or associated equipment; heavy electrical machinery; pumps including vacuum pumps; compressors; fans; blowers; oil hydraulic equipment; pneumatic equipment; metal working machinery; manipulators; robots and / or their application systems; tools; molds or dies; rolls; conveying equipment; elevating equipment; materials handling equipment; textile machinery; sewing machines; printing and / or related machinery; paper converting machinery; chemical machinery; mining and / or construction machinery and / or related equipment; machinery and / or implements for agriculture, forestry and / or fisheries; safety and / or environment preservation equipment; tractors; precision bearings; chains; gears; power transmission equipment; lubricating equipment; valves; pipe fittings; and / or application systems for any of the previously mentioned equipment or machinery etc.).

[0366] The UE 3 may, for example, be an item of transport equipment (for example transport equipment such as: rolling stocks; motor vehicles; motor cycles; bicycles; trains; buses; carts; rickshaws; ships and other watercraft; aircraft; rockets; satellites; drones; balloons etc.).

[0367] The UE 3 may, for example, be an item of information and communication equipment (for example information and communication equipment such as: electronic computer and related equipment; communication and related equipment; electronic components etc.).

[0368] The UE 3 may, for example, be a refrigerating machine, a refrigerating machine applied product, an item of trade and / or service industry equipment, a vending machine, an automatic service machine, an office machine or equipment, a consumer electronic and electronic appliance (for example a consumer electronic appliance such as: audio equipment; video equipment; a loud 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 cleaner etc.).

[0369] The UE 3 may, for example, be an electrical application system or equipment (for example an electrical application system or equipment such as: an x-ray system; a particle accelerator; radio isotope equipment; sonic equipment; electromagnetic application equipment; electronic power application equipment etc.).

[0370] The UE 3 may, for example, be an electronic lamp, a luminaire, a measuring instrument, an analyzer, a tester, or a surveying or sensing instrument (for example a surveying or sensing instrument such as: a smoke alarm; a human alarm sensor; a motion sensor; a wireless tag etc.), a watch or clock, a laboratory instrument, optical apparatus, medical equipment and / or system, a weapon, an item of cutlery, a hand tool, or the like.

[0371] The UE 3 may, for example, be a wireless-equipped personal digital assistant or related equipment (such as a wireless card or module designed for attachment to or for insertion into another electronic device (for example a personal computer, electrical measuring machine)).

[0372] The UE 3 may be a device or a part of a system that provides applications, services, and solutions described below, as to "internet of things (IoT)", using a variety of wired and / or wireless communication technologies.

[0373] Internet of Things devices (or "things") may be equipped with appropriate electronics, software, sensors, network connectivity, and / or the like, which enable these devices to collect and exchange data with each other and with other communication devices. IoT devices may comprise automated equipment that follow software instructions stored in an internal memory. IoT devices may operate without requiring human supervision or interaction. IoT devices might also remain stationary and / or inactive for a long period of time. IoT devices may be implemented as a part of a (generally) stationary apparatus. IoT devices may also be embedded in non-stationary apparatus (e.g. vehicles) or attached to animals or persons to be monitored / tracked.

[0374] It will be appreciated that IoT technology can be implemented on any communication devices that can connect to a communications network for sending / receiving data, regardless of whether such communication devices are controlled by human input or software instructions stored in memory.

[0375] It will be appreciated that IoT devices are sometimes also referred to as Machine-Type Communication (MTC) devices or Machine-to-Machine (M2M) communication devices or Narrow Band-IoT UE (NB-IoT UE). It will be appreciated that a UE 3 may support one or more IoT or MTC applications.

[0376] The UE 3 may be a smart phone or a wearable device (e.g. smart glasses, a smart watch, a smart ring, or a hearable device). For a wearable device, the UE 3 may be a reduced capability device (RedCap).

[0377] The UE 3 may be a car, or a connected car, or an autonomous car, or a vehicle device, or a motorcycle or V2X (Vehicle to Everything) communication module (e.g. Vehicle to Vehicle communication module, Vehicle to Infrastructure communication module, Vehicle to People communication module and Vehicle to Network communication module).

[0378] (R)AN node 　　Fig. 22 is an example of a block diagram illustrating the main components of an exemplary (R)AN node 5, for example a base station ('eNB' in LTE, 'gNB' in 5G, a base station for 5G beyond, a base station for 6G). As shown, the (R)AN node 5 includes a transceiver circuit 51 which is operable to transmit signals to and to receive signals from connected UE(s) 3 via one or more antennas 52 and to transmit signals to and to receive signals from other network nodes (either directly or indirectly) via a network interface 53. A controller 54 controls the operation of the (R)AN node 5 in accordance with software stored in a memory 55. Software may be pre-installed in the memory and / or may be downloaded via the telecommunication network or from a removable data storage device (RMD), for example. The software includes, among other things, an operating system 551 and a communications control module 552 having at least a transceiver control module 5521.

[0379] The communications control module 552 (using its transceiver control sub-module) is responsible for handling (generating / sending / receiving) signalling between the (R)AN node 5 and other nodes, such as the UE 3, another (R)AN node 5, the AMF 70 and the UPF 72 (e.g., directly or indirectly). The signalling may include, for example, appropriately formatted signalling messages relating to a radio connection and a connection with the core network 7 (for a particular UE 3), and in particular, relating to connection establishment and maintenance (e.g., RRC connection establishment and other RRC messages), NG Application Protocol (NGAP) messages (i.e. messages by N2 reference point) and Xn application protocol (XnAP) messages (i.e. messages by Xn reference point), etc. Such signalling may also include, for example, broadcast information (e.g., Master Information and System information) in a sending case.

[0380] The controller 54 is also configured (by software or hardware) to handle related tasks such as, when implemented, UE mobility estimate and / or moving trajectory estimation.

[0381] The (R)AN node 5 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0382] The 5G Femtocell 501, SecGW 502, NAT 503, 5G MN RAN 503, and 5G SN Femtocell 501 may have same components to the (R)AN node 5. The (R)AN node 5 may be expressed as a RAN node, 5G RAN node, RAN, (R)AN etc.

[0383] System overview of (R)AN node 5 based on O-RAN architecture 　　Fig. 23 schematically illustrates an example of a (R)AN node 5 based on O-RAN architecture to which the (R)AN node 5 aspects are applicable.

[0384] The (R)AN node 5 based on O-RAN architecture represents a system overview in which the (R)AN node is split into a Radio Unit (RU) 60, Distributed Unit (DU) 61 and Centralized Unit (CU) 62. In some aspects, each unit may be combined. For example, the RU 60 can be integrated / combined with the DU 61 as an integrated / combined unit, the DU 61 can be integrated / combined with the CU 62 as another integrated / combined unit. Any functionality in the description for a unit (e.g., one of RU 60, DU 61 and CU 62) can be implemented in the integrated / combined unit above. Further, CU 62 can separate into two functional units such as CU Control plane (CP) and CU User plane (UP). The CU CP has a control plane functionality in the (R)AN node 5. The CU UP has a user plane functionality in the (R)AN node 5. Each CU CP is connected to the CU UP via an appropriate interface (such as the so-called "E1" interface and / or the like).

[0385] The UE 3 and a respective serving RU 60 are connected via an appropriate air interface (for example the so-called "Uu" interface and / or the like). Each RU 60 is connected to the DU 61 via an appropriate interface (such as the so-called "Front haul", "Open Front haul", "F1" interface and / or the like). Each DU 61 is connected to the CU 62 via an appropriate interface (such as the so-called "Mid haul", "Open Mid haul", "E2" interface and / or the like). Each CU 62 is also connected to nodes in the core network 7 (such as the so-called core network nodes) via an appropriate interface (such as the so-called "Back haul", "Open Back haul", "N2" / "N3" interface(s) and / or the like). In addition, a user plane part of the DU 61 can also be connected to the core network nodes via an appropriate interface (such as the so-called "N3" interface(s) and / or the like).

[0386] Depending on functionality split among the RU 60, DU 61 and CU 62, each unit provides some of the functionality that is provided by the (R)AN node 5. For example, the RU 60 may provide a functionalities to communicate with a UE 3 (e.g., the Network Relay UE 300) over air interface, the DU 61 may provide functionalities to support MAC layer and RLC layer, the CU 62 may provide functionalities to support PDCP layer, SDAP layer and RRC layer.

[0387] Radio Unit (RU) 　　Fig. 24 is an example of a block diagram illustrating the main components of an exemplary RU 60, for example a RU part of base station ('eNB' in LTE, 'gNB' in 5G, a base station for 5G beyond, a base station for 6G). As shown, the RU 60 includes a transceiver circuit 601 which is operable to transmit signals to and to receive signals from connected UE(s) 3 via one or more antennas 602 and to transmit signals to and to receive signals from other network nodes or network unit (either directly or indirectly) via a network interface 603. A controller 604 controls the operation of the RU 60 in accordance with software stored in a memory 605. Software may be pre-installed in the memory and / or may be downloaded via the telecommunication network or from a removable data storage device (RMD), for example. The software includes, among other things, an operating system 6051 and a communications control module 6052 having at least a transceiver control module 60521.

[0388] The communications control module 6052 (using its transceiver control sub-module) is responsible for handling (generating / sending / receiving) signalling between the RU 60 and other nodes or units, such as the UE 3, another RU 60 and DU 61 (e.g., directly or indirectly). The signalling may include, for example, appropriately formatted signalling messages relating to a radio connection and a connection with the RU 60 (for a particular UE 3 (e.g., the Network Relay UE 300)), and in particular, relating to MAC layer and RLC layer.

[0389] The controller 604 is also configured (by software or hardware) to handle related tasks such as, when implemented, UE mobility estimate and / or moving trajectory estimation.

[0390] The RU 60 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0391] As described above, the RU 60 can be integrated / combined with the DU 61 as an integrated / combined unit. Any functionality in the description for the RU 60 can be implemented in the integrated / combined unit above.

[0392] Distributed Unit (DU) 　　Fig. 25 is an example of a block diagram illustrating the main components of an exemplary DU 61, for example a DU part of a base station ('eNB' in LTE, 'gNB' in 5G, a base station for 5G beyond, a base station for 6G). As shown, the apparatus includes a transceiver circuit 611 which is operable to transmit signals to and to receive signals 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 a memory 614. Software may be pre-installed in the memory 614 and / or may be downloaded via the telecommunication network or from a removable data storage device (RMD), for example. 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 communications control module 6142 (using its transceiver control module 61421) is responsible for handling (generating / sending / receiving) signalling between the DU 61 and other nodes or units, such as the RU 60 and other nodes and units.

[0393] The DU 61 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0394] As described above, the RU 60 can be integrated / combined with the DU 61 or CU 62 as an integrated / combined unit. Any functionality in the description for DU 61 can be implemented in one of the integrated / combined unit above. The 5G DU Femtocell 501 may have same components to the DU 61.

[0395] Centralized Unit (CU) 　　Fig. 26 is an example of a block diagram illustrating the main components of an exemplary CU 62, for example a CU part of base station ('eNB' in LTE, 'gNB' in 5G, a base station for 5G beyond, a base station for 6G). As shown, the apparatus includes a transceiver circuit 621 which is operable to transmit signals to and to receive signals 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 a memory 624. Software may be pre-installed in the memory 624 and / or may be downloaded via the telecommunication network or from a removable data storage device (RMD), for example. 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 communications control module 6242 (using its transceiver control module 62421) is responsible for handling (generating / sending / receiving) signalling between the CU 62 and other nodes or units, such as the DU 61 and other nodes and units.

[0396] The CU 62 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0397] As described above, the CU 62 can be integrated / combined with the DU 61 as an integrated / combined unit. Any functionality in the description for the CU 62 can be implemented in the integrated / combined unit above. 　　The 5G CU Femtocell 503 may have same components to the CU 62.

[0398] AMF 　　Fig. 27 is an example of a block diagram illustrating the main components of the AMF 70. As shown, the apparatus includes a transceiver circuit 701 which is operable to transmit signals to and to receive signals from other nodes (including the UE 3 (e.g., the Network Relay UE 300 and the UE 3), the NSSF 76) via a network interface 702. A controller 703 controls the operation of the AMF 70 in accordance with software stored in a memory 704. Software may be pre-installed in the memory 704 and / or may be downloaded via the telecommunication network or from a removable data storage device (RMD), for example. The 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) signalling between the AMF 70 and other nodes, such as the UE 3 (e.g., via the (R)AN node 5) and other core network nodes (including core network nodes in the HPLMN of the UE 3) when the UE 3 is roaming-in. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a registration request message and associated response messages) relating to access and mobility management procedures (for the UE 3).

[0399] The AMF 70 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0400] SMF 　　Fig. 28 is an example of a block diagram illustrating the main components of the SMF 71. As shown, the apparatus includes a transceiver circuit 711 which is operable to transmit signals to and to receive signals 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. Software may be pre-installed in the memory 714 and / or may be downloaded via the telecommunication network or from a removable data storage device (e.g., a removable memory device (RMD)), for example. The software includes, among other things, an operating system 7141 and a communications control module 7142 having at least a transceiver control module 71421. The communications control module 7142 (using its transceiver control module 71421) is responsible for handling (generating / sending / receiving) signalling between the SMF 71 and other nodes, such as the AMF 70 and other core network nodes (including core network nodes in the HPLMN of the UE 3 (e.g., the Network Relay UE 300 and the UE 3)) when the UE 3 is roaming-in. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a HTTP restful methods based on the service based interfaces) relating to policy management procedures (for the UE 3).

[0401] The SMF 71 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0402] UPF 　　Fig. 29 is an example of a block diagram illustrating the main components of the UPF 72. As shown, the apparatus includes a transceiver circuit 721 which is operable to transmit signals to and to receive signals 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. Software may be pre-installed in the memory 724 and / or may be downloaded via the telecommunication network or from a removable data storage device (e.g., a removable memory device (RMD)), for example. The software includes, among other things, an operating system 7241 and a communications control module 7242 having at least a transceiver control module 72421. The communications control module 7242 (using its transceiver control module 72421) is responsible for handling (generating / sending / receiving) signalling between the UPF 72 and other nodes, such as the SMF 71 and other core network nodes (including core network nodes in the HPLMN of the UE 3 (e.g., the Network Relay UE 300 and the UE 3)) when the UE 3 is roaming-in. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a HTTP restful methods based on the service based interfaces) relating to policy management procedures (for the UE 3).

[0403] The UPF 72 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0404] PCF 　　Fig. 30 is an example of a block diagram illustrating the main components of the PCF 73. As shown, the apparatus includes a transceiver circuit 731 which is operable to transmit signals to and to receive signals 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. Software may be pre-installed in the memory 734 and / or may be downloaded via the telecommunication network or from a removable data storage device (e.g., a removable memory device (RMD)), for example. The 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) signalling between the PCF 73 and other nodes, such as the AMF 70 and other core network nodes (including core network nodes in the HPLMN of the UE 3 (e.g., the Network Relay UE 300 and the UE 3)) when the UE 3 is roaming-in. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a HTTP restful methods based on the service based interfaces) relating to policy management procedures (for the UE 3).

[0405] The PCF 73 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0406] NWDAF 　　Fig. 31 is an example of a block diagram illustrating the main components of the NWDAF 74. As shown, the apparatus includes a transceiver circuit 741 which is operable to transmit signals to and to receive signals from other nodes (including the AMF 70 and the UDM 75) via a network interface 742. A controller 743 controls the operation of the NWDAF 74 in accordance with software stored in a memory 744. Software may be pre-installed in the memory 744 and / or may be downloaded via the telecommunication network or from a removable data storage device (e.g., a removable memory device (RMD)), for example. The 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) signalling between the NWDAF 74 and other nodes, such as the AMF 70 and other core network nodes (including core network nodes in the HPLMN of the UE 3) when the UE 3 is roaming-in. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a HTTP restful methods based on the service based interfaces) relating to policy management procedures (for the UE 3).

[0407] The NWDAF 74 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0408] UDM 　　Fig. 32 is an example of a block diagram illustrating the main components of the UDM 75. As shown, the apparatus includes a transceiver circuit 751 which is operable to transmit signals to and to receive signals 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 a memory 754. Software may be pre-installed in the memory 754 and / or may be downloaded via the telecommunication network or from a removable data storage device (RMD), for example. The 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) signalling between the UDM 75 and other nodes, such as the AMF 70 and other core network nodes (including core network nodes in the VPLMN of the UE 3 (e.g., the Network Relay UE 300 and the UE 3)) when the UE 3 is roaming-out. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a HTTP restful methods based on the service based interfaces) relating to mobility management procedures (for the UE 3).

[0409] The UDM 75 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0410] NSSF 　　Fig. 33 is an example of a block diagram illustrating the main components of the NSSF 76. As shown, the apparatus includes a transceiver circuit 761 which is operable to transmit signals to and to receive signals 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. Software may be pre-installed in the memory 764 and / or may be downloaded via the telecommunication network or from a removable data storage device (RMD), for example. The 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) signalling between the NSSF 76 and other nodes, such as the AMF 70 and other core network nodes (including core network nodes in the VPLMN of the UE 3) when the UE 3 is roaming-out. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a HTTP restful methods based on the service based interfaces) relating to mobility management procedures (for the UE 3).

[0411] The NSSF 76 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0412] AAA Server 　　Fig. 34 is an example of a block diagram illustrating the main components of the AAA Server 77. As shown, the apparatus includes a transceiver circuit 771 which is operable to transmit signals to and to receive signals from other nodes (including the AMF 70) via a network interface 772. A controller 773 controls the operation of the AAA Server 77 in accordance with the software stored in a memory 774. The Software may be pre-installed in the memory 774 and / or may be downloaded via the telecommunication network or from a removable data storage device (e.g., a removable memory device (RMD)), for example. The 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) signalling between the AAA Server 77 and other nodes, such as the AMF 70 and other core network nodes (including core network nodes in the HPLMN of the UE 3) when the UE 3 is roaming-in. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a HTTP restful methods based on the service based interfaces) relating to network data analytics function procedures (for the UE 3).

[0413] The AAA Server 77 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0414] NRF 　　Fig. 35 is an example of a block diagram illustrating the main components of the NRF 78. As shown, the apparatus includes a transceiver circuit 781 which is operable to transmit signals to and to receive signals from other nodes (including the AMF 70) via a network interface 782. A controller 783 controls the operation of the NRF 78 in accordance with the software stored in a memory 784. The Software may be pre-installed in the memory 784 and / or may be downloaded via the telecommunication network or from a removable data storage device (e.g., a removable memory device (RMD)), for example. The software includes, among other things, an operating system 7841 and a communications control module 7842 having at least a transceiver control module 78421. The communications control module 7842 (using its transceiver control module 78421) is responsible for handling (generating / sending / receiving) signalling between the NRF 78 and other nodes, such as the AMF 70 and other core network nodes (including core network nodes in the HPLMN of the UE 3) when the UE 3 is roaming-in. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a HTTP restful methods based on the service based interfaces) relating to network data analytics function procedures (for the UE 3).

[0415] The NRF 78 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0416] AF 　　Fig. 36 is an example of a block diagram illustrating the main components of the AF 201. As shown, the apparatus includes a transceiver circuit 2011 which is operable to transmit signals to and to receive signals from other nodes (including the UE 3 (e.g., the Network Relay UE 300 and the UE 3)) via a network interface 2012. A controller 2013 controls the operation of the AF 201 in accordance with software stored in a memory 2014. Software may be pre-installed in the memory 2014 and / or may be downloaded via the telecommunication network or from a removable data storage device (e.g., a removable memory device (RMD)), for example. The software includes, among other things, an operating system 20141 and a communications control module 20142 having at least a transceiver control module 201421. The communications control module 20142 (using its transceiver control module 201421) is responsible for handling (generating / sending / receiving) signalling between the AF 201 and other nodes, such as the UE 3 and other core network nodes (including core network nodes in the HPLMN of the UE 3) when the UE 3 is roaming-in. Such signalling may include, for example, appropriately formatted signalling messages (e.g., a HTTP restful methods based on the service based interfaces) relating to policy management procedures (for the UE 3).

[0417] The AF 201 may support the Non-Public Network (NPN), The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).

[0418] Modifications and Alternatives 　　Detailed aspects have been described above. As those skilled in the art will appreciate, a number of modifications and alternatives can be made to the above aspects whilst still benefiting from the disclosures embodied therein. By way of illustration only a number of these alternatives and modifications will now be described.

[0419] In the above description, the UE 3 and the network apparatus are described for ease of understanding as having a number of discrete modules (such as the communication control modules). Whilst these modules may be provided in this way for certain applications, for example where an existing system has been modified to implement the disclosure, in other applications, for example in systems designed with the inventive features in mind from the outset, these modules may be built into the overall operating system or code and so these modules may not be discernible as discrete entities. These modules may also be implemented in software, hardware, firmware or a mix of these.

[0420] Each controller may comprise any suitable form of processing circuitry including (but not limited to), for example: one or more hardware implemented computer processors; microprocessors; central processing units (CPUs); arithmetic logic units (ALUs); input / output (IO) circuits; internal memories / caches (program and / or data); processing registers; communication buses (e.g. control, data and / or address buses); direct memory access (DMA) functions, hardware or software implemented counters, pointers and / or timers; and / or the like.

[0421] In the above aspects, a number of software modules were described. As those skilled in the art will appreciate, the software modules may be provided in compiled or un-compiled form and may be supplied to the UE 3 and the network apparatus as a signal over a computer network, or on a recording medium. Further, the functionality performed by part or all of this software may be performed using one or more dedicated hardware circuits. However, the use of software modules is preferred as it facilitates the updating of the UE 3 and the network apparatus in order to update their functionalities.

[0422] In the above aspects, a 3GPP radio communications (radio access) technology is used. However, any other radio communications technology (e.g., WLAN, Wi-Fi, WiMAX, Bluetooth, etc.) and other fix line communications technology (e.g. BBF Access, Cable Access, optical access, etc.) may also be used in accordance with the above aspects.

[0423] Items of user equipment might include, for example, communication devices such as mobile telephones, smartphones, user equipment, personal digital assistants, laptop / tablet computers, web browsers, e-book readers and / or the like. Such mobile (or even generally stationary) devices are typically operated by a user, although it is also possible to connect so-called 'Internet of Things' (IoT) devices and similar machine-type communication (MTC) devices to the network. For simplicity, the present application refers to mobile devices (or UEs) in the description but it will be appreciated that the technology described can be implemented on any communication devices (mobile and / or generally stationary) that can connect to a communications network for sending / receiving data, regardless of whether such communication devices are controlled by human input or software instructions stored in memory.

[0424] Various other modifications will be apparent to those skilled in the art and will not be described in further detail here.

[0425] As will be appreciated by one of skill in the art, the present disclosure may be embodied as a method, and system. Accordingly, the present disclosure may take the form of an entirely hardware embodiment, a software embodiment or an embodiment combining software and hardware aspects.

[0426] It will be understood that each block of the block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general-purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a plurality of microprocessors, one or more microprocessors, or any other such configuration.

[0427] The methods or algorithms described in connection with the examples disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. A storage medium may be coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC.

[0428] The previous description of the disclosed examples is provided to enable any person skilled in the art to make or use the present disclosure. Various modifications to these examples will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other examples without departing from the spirit or scope of the disclosure. Thus, the present disclosure is not intended to be limited to the examples shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0429] While the disclosure has been particularly shown and described with reference to exemplary Aspects thereof, the disclosure is not limited to these Aspects. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by this document. For example, the Aspects above are not limited to 5GS, and the Aspects are also applicable to communication system other than 5GS (e.g., 6G system, 5G beyond system).

[0430] This application is based upon and claims the benefit of priority from Indian Patent Application No. 202311060522, filed on September 8, 2023, the disclosure of which is incorporated herein in its entirety by reference.

[0431] Supplementary notes 　　The whole or part of the example Aspects disclosed above can be described as, but not limited to, the following supplementary notes. 　　<First Supplementary notes> 　　　　(Supplementary note A1) 　　A method of a User Equipment (UE) comprising: 　　performing a registration procedure using a 5G Femtocell. 　　　　(Supplementary note A2) 　　A method of a network node comprising: 　　performing a registration procedure using a 5G Femtocell. 　　　　(Supplementary note A3) 　　The method according to supplementary note A2, wherein the network node is a core network node. 　　　　(Supplementary note A4) 　　The method according to supplementary note A3, wherein the core network node is an Access and Mobility Management Function (AMF) node. 　　　　(Supplementary note A5) 　　The method according to supplementary note A2, wherein the network node is a 5G Femtocell. 　　　　(Supplementary note A6) 　　The method according to supplementary note A5, wherein the 5G Femtocell includes a 5G Distributed Unit (DU) Femtocell and a 5G Centralized Unit (CU) Femtocell. 　　　　(Supplementary note A7) 　　A method of a network node comprising: 　　performing a 5G Femtocell setup procedure. 　　　　(Supplementary note A8) 　　The method according to supplementary note A7, wherein the network node is a 5G Femtocell. 　　　　(Supplementary note A9) 　　The method according to supplementary note A7, wherein the network node is a core network node. 　　　　(Supplementary note A10) 　　A User Equipment (UE) comprising: 　　means for performing a registration procedure using a 5G Femtocell. 　　　　(Supplementary note A11) 　　A network node comprising: 　　means for performing a registration procedure using a 5G Femtocell. 　　　　(Supplementary note A12) 　　The network node according to supplementary note A11, wherein the network node is a core network node. 　　　　(Supplementary note A13) 　　The network node according to supplementary note A12, wherein the core network node is an Access and Mobility Management Function (AMF) node. 　　　　(Supplementary note A14) 　　The network node according to supplementary note A11, wherein the network node is a 5G Femtocell. 　　　　(Supplementary note A15) 　　The network node according to supplementary note A14, wherein the 5G Femtocell includes a 5G Distributed Unit (DU) Femtocell and a 5G Centralized Unit (CU) Femtocell. 　　　　(Supplementary note A16) 　　A network node comprising: 　　means for performing a 5G Femtocell setup procedure. 　　　　(Supplementary note A17) 　　The network node according to supplementary note A16, wherein the network node is a 5G Femtocell. 　　　　(Supplementary note A18) 　　The network node according to supplementary note A16, wherein the network node is a core network node. 　　　　(Supplementary note A19) 　　The method according to supplementary note A2, wherein the network node receives a message including Subscriber data for the UE. 　　　　(Supplementary note A20) 　　The method according to supplementary note A19, wherein the Subscriber data includes an Allowed CSG Identifier list, the Allowed CSG Identifier indicating a Closed Subscriber Group identifier (CSG ID). 　　　　(Supplementary note A21) 　　The method according to supplementary note A7, wherein the network node receives a message including a CSG ID. 　　　　(Supplementary note A22) 　　The method according to supplementary note A21, wherein the CSG ID is a part of a Closed Access Group identifier (CAG ID). 　　　　(Supplementary note A23) 　　The method according to supplementary note A22, wherein the CSG ID is expressed in a CSG Identifier field (27 bit-length) in the CAG ID. 　　<Second Supplementary notes> 　　　　(Supplementary note B1) 　　A method of a User Equipment (UE) comprising: 　　performing a PDU Session Establishment procedure related to 5G Femtocell. 　　　　(Supplementary note B2) 　　A method of a network node comprising: 　　performing a PDU Session Establishment procedure related to 5G Femtocell. 　　　　(Supplementary note B3) 　　The method according to supplementary note B2, wherein the network node is a core network node. 　　　　(Supplementary note B4) 　　The method according to supplementary note B3, wherein the core network node is a User Plane Function (UPF) node. 　　　　(Supplementary note B5) 　　The method according to supplementary note B4, wherein the UPF node is located at a private premise network. 　　　　(Supplementary note B6) 　　A User Equipment (UE) comprising: 　　means for performing a PDU Session Establishment procedure related to 5G Femtocell. 　　　　(Supplementary note B7) 　　A network node comprising: 　　means for performing a PDU Session Establishment procedure related to 5G Femtocell. 　　　　(Supplementary note B8) 　　The network node according to supplementary note B7, wherein the network node is a core network node. 　　　　(Supplementary note B9) 　　The network node according to supplementary note B8, wherein the core network node is a User Plane Function (UPF) node. 　　　　(Supplementary note B10) 　　The network node according to supplementary note B9, wherein the UPF node is located at a private premise network.

[0432] 1　　TELECOMMUNICATION SYSTEM 3　　USER EQUIPMENT (UE) 5　　(R)AN NODE 501　　5G FEMTOCELL 502　　SECGW 503　　NETWORK ADDRESS TRANSLATION (NAT) 60　　RADIO UNIT (RU) 61　　DISTRIBUTED UNIT (DU) 62　　CENTRALIZED UNIT (CU) 7　　CORE NETWORK 70　　ACCESS AND MOBILITY MANAGEMENT FUNCTION (AMF) 71　　SESSION MANAGEMENT FUNCTION (SMF) 72　　USER PLANE FUNCTION (UPF) 73　　POLICY CONTROL FUNCTION (PCF) 74　　NETWORK DATA ANALYTICS FUNCTION (NWDAF) 75　　UNIFIED DATA MANAGEMENT (UDM) 76　　NETWORK SLICE SELECTION FUNCTION (NSSF) 77　　AAA SERVER 78　　NETWORK REPOSITORY FUNCTION (NRF) 20　　DATA NETWORK 201　　APPLICATION FUNCTION (AF) 31, 51, 601, 611, 621, 701, 711, 721, 731, 741, 751, 761, 771, 781, 2011　　TRANSCEIVER CIRCUIT 32, 52, 602　　ANTENNA 53, 603, 612, 622, 702, 712, 722, 732, 742, 752, 762, 772, 782, 2012　　NETWORK INTERFACE 33, 54, 604, 613, 623, 703, 713, 723, 733, 743, 753, 763, 773, 783, 2013　　CONTROLLER 34　　USER INTERFACE 35　　UNIVERSAL SUBSCRIBER IDENTITY MODULE (USIM) 36, 55, 605, 614, 624, 704, 714, 724, 734, 744, 754, 764, 774, 784, 2014　　MEMORY 361, 551, 6051, 6141, 6241, 7041, 7141, 7241, 7341, 7441, 7541, 7641, 7741, 7841, 20141　　OPERATING SYSTEM 362, 552, 6052, 6142, 6242, 7042, 7142, 7242, 7342, 7442, 7542, 7642, 7742, 7842, 20142　　COMMUNICATIONS CONTROL MODULE 3621, 5521, 60521, 61421, 62421, 70421, 71421, 72421, 73421, 74421, 75421, 76421, 77421, 78421, 201421　　TRANSCEIVER CONTROL MODULE

Claims

1. A method of a User Equipment (UE) comprising: 　　performing a registration procedure using a 5G Femtocell.

2. A method of a network node comprising: 　　performing a registration procedure using a 5G Femtocell.

3. The method according to claim 2, wherein the network node is a core network node.

4. The method according to claim 3, wherein the core network node is an Access and Mobility Management Function (AMF) node.

5. The method according to claim 2, wherein the network node is a 5G Femtocell.

6. The method according to claim 5, wherein the 5G Femtocell includes a 5G Distributed Unit (DU) Femtocell and a 5G Centralized Unit (CU) Femtocell.

7. A method of a network node comprising: 　　performing a 5G Femtocell setup procedure.

8. The method according to claim 7, wherein the network node is a 5G Femtocell.

9. The method according to claim 7, wherein the network node is a core network node.

10. A User Equipment (UE) comprising: 　　means for performing a registration procedure using a 5G Femtocell.

11. A network node comprising: 　　means for performing a registration procedure using a 5G Femtocell.

12. The network node according to claim 11, wherein the network node is a core network node.

13. The network node according to claim 12, wherein the core network node is an Access and Mobility Management Function (AMF) node.

14. The network node according to claim 11, wherein the network node is a 5G Femtocell.

15. The network node according to claim 14, wherein the 5G Femtocell includes a 5G Distributed Unit (DU) Femtocell and a 5G Centralized Unit (CU) Femtocell.

16. A network node comprising: 　　means for performing a 5G Femtocell setup procedure.

17. The network node according to claim 16, wherein the network node is a 5G Femtocell.

18. The network node according to claim 16, wherein the network node is a core network node.

19. The method according to claim 2, wherein the network node receives a message including Subscriber data for the UE.

20. The method according to claim 19, wherein the Subscriber data includes an Allowed CSG Identifier list, the Allowed CSG Identifier indicating a Closed Subscriber Group identifier (CSG ID).

21. The method according to claim 7, wherein the network node receives a message including a CSG ID.

22. The method according to claim 21, wherein the CSG ID is a part of a Closed Access Group identifier (CAG ID).

23. The method according to claim 22, wherein the CSG ID is expressed in a CSG Identifier field (27 bit-length) in the CAG ID.

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