ETSI TS 124 501 V15.5.0 (2019-10)

5G; Non-Access-Stratum (NAS) protocol for 5G System (5GS); Stage 3 (3GPP TS 24.501 version 15.5.0 Release 15)

RTS/TSGC-0124501vf50

General Information

• Status: Published
• Publication Date: 30-Sep-2019
• Technical Committee: 3GPP CT 1 - MM/CC/SM [lu] (formely CN1)
• Current Stage: 12 - Completion
• Completion Date: 01-Oct-2019

Standards Content (Sample)

ETSI TS 124 501 V15.5.0 (2019-10)






TECHNICAL SPECIFICATION
5G;
Non-Access-Stratum (NAS) protocol for 5G System (5GS)
Stage 3
(3GPP TS 24.501 version 15.5.0 Release 15)

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1 ETSI TS 124 501 V15.5.0 (2019-10)



Reference
RTS/TSGC-0124501vf50
Keywords
5G
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2 ETSI TS 124 501 V15.5.0 (2019-10)
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Modal verbs terminology
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ETSI

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3 ETSI TS 124 501 V15.5.0 (2019-10)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 18
1 Scope . 19
2 References . 19
3 Definitions and abbreviations . 21
3.1 Definitions . 21
3.2 Abbreviations . 25
4 General . 27
4.1 Overview . 27
4.2 Coordination between the protocols for 5GS mobility management and 5GS session management . 27
4.3 UE domain selection . 28
4.3.1 UE's usage setting . 28
4.3.2 Domain selection for UE originating sessions / calls . 28
4.3.3 Change of UE's usage setting . 30
4.3.4 Change or determination of IMS voice availability . 30
4.4 NAS security . 31
4.4.1 General . 31
4.4.2 Handling of 5G NAS security contexts. 31
4.4.2.1 General . 31
4.4.2.2 Establishment of a mapped 5G NAS security context during inter-system change from S1 mode
to N1 mode in 5GMM-CONNECTED mode . 33
4.4.2.3 Establishment of a 5G NAS security context during N1 mode to N1 mode handover . 34
4.4.2.4 Establishment of an EPS security context during inter-system change from N1 mode to S1 mode
in 5GMM-CONNECTED mode . 35
4.4.2.5 Establishment of secure exchange of NAS messages . 35
4.4.2.6 Change of security keys . 37
4.4.3 Handling of NAS COUNT and NAS sequence number . 37
4.4.3.1 General . 37
4.4.3.2 Replay protection . 38
4.4.3.3 Integrity protection and verification . 38
4.4.3.4 Ciphering and deciphering . 38
4.4.3.5 NAS COUNT wrap around . 39
4.4.4 Integrity protection of NAS signalling messages. 39
4.4.4.1 General . 39
4.4.4.2 Integrity checking of NAS signalling messages in the UE . 40
4.4.4.3 Integrity checking of NAS signalling messages in the AMF . 40
4.4.5 Ciphering of NAS signalling messages . 42
4.4.6 Protection of initial NAS signalling messages . 42
4.5 Unified access control . 44
4.5.1 General . 44
4.5.2 Determination of the access identities and access category associated with a request for access . 45
4.5.3 Operator-defined access categories . 49
4.5.4 Access control and checking . 50
4.5.4.1 Access control and checking in 5GMM-IDLE mode . 50
4.5.4.2 Access control and checking in 5GMM-CONNECTED mode and in 5GMM-CONNECTED
mode with RRC inactive indication . 51
4.5.5 Exception handling and avoiding double barring . 53
4.5.6 Mapping between access categories/access identities and RRC establishment cause . 56
4.6 Network slicing . 57
4.6.1 General . 57
4.6.2 Mobility management aspects. 58
4.6.2.1 General . 58
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4 ETSI TS 124 501 V15.5.0 (2019-10)
4.6.2.2 NSSAI storage . 58
4.6.2.3 Provision of NSSAI to lower layers in 5GMM-IDLE mode . 59
4.6.3 Session management aspects . 61
4.7 NAS over non-3GPP access . 61
4.7.1 General . 61
4.7.2 5GS mobility management aspects . 61
4.7.2.1 General . 61
4.7.2.2 Establishment cause for non-3GPP access . 62
4.7.3 5GS session management aspects . 62
4.7.4 Limited service state over non-3GPP access . 62
4.8 Interworking with E-UTRAN connected to EPC . 63
4.8.1 General . 63
4.8.2 Single-registration mode . 63
4.8.2.1 General . 63
4.8.2.2 Single-registration mode with N26 interface . 63
4.8.2.3 Single-registration mode without N26 interface . 63
4.8.2.3.1 Interworking between NG-RAN and E-UTRAN . 63
4.8.2.3.2 Interworking between N3IWF connected to 5GCN and E-UTRAN . 64
4.8.3 Dual-registration mode . 65
4.8.4 Core Network selection . 66
4.9 Disabling and re-enabling of UE's N1 mode capability . 66
4.9.1 General . 66
4.9.2 Disabling and re-enabling of UE's N1 mode capability for 3GPP access . 67
4.9.3 Disabling and re-enabling of UE's N1 mode capability for non-3GPP access. 67
4.10 Interworking with ePDG connected to EPC . 68
4.11 UE configuration parameter updates . 68
5 Elementary procedures for 5GS mobility management . 68
5.1 Overview . 68
5.1.1 General . 68
5.1.2 Types of 5GMM procedures . 68
5.1.3 5GMM sublayer states . 70
5.1.3.1 General . 70
5.1.3.2 5GMM sublayer states . 70
5.1.3.2.1 5GMM sublayer states in the UE. 70
5.1.3.2.1.1 General . 70
5.1.3.2.1.2 Main states . 70
5.1.3.2.1.2.1 5GMM-NULL . 70
5.1.3.2.1.2.2 5GMM-DEREGISTERED . 70
5.1.3.2.1.2.3 5GMM-REGISTERED-INITIATED . 71
5.1.3.2.1.2.4 5GMM-REGISTERED . 71
5.1.3.2.1.2.5 5GMM-DEREGISTERED-INITIATED . 71
5.1.3.2.1.2.6 5GMM-SERVICE-REQUEST-INITIATED. 71
5.1.3.2.1.3 Substates of state 5GMM-DEREGISTERED . 71
5.1.3.2.1.3.1 General . 71
5.1.3.2.1.3.2 5GMM-DEREGISTERED.NORMAL-SERVICE . 71
5.1.3.2.1.3.3 5GMM-DEREGISTERED.LIMITED-SERVICE . 71
5.1.3.2.1.3.4 5GMM-DEREGISTERED.ATTEMPTING-REGISTRATION . 71
5.1.3.2.1.3.5 5GMM-DEREGISTERED.PLMN-SEARCH . 71
5.1.3.2.1.3.6 5GMM-DEREGISTERED.NO-SUPI . 72
5.1.3.2.1.3.7 5GMM-DEREGISTERED.NO-CELL-AVAILABLE . 72
5.1.3.2.1.3.8 5GMM-DEREGISTERED.eCALL-INACTIVE . 72
5.1.3.2.1.3.9 5GMM-DEREGISTERED.INITIAL-REGISTRATION-NEEDED . 72
5.1.3.2.1.4 Substates of state 5GMM-REGISTERED . 72
5.1.3.2.1.4.1 General . 72
5.1.3.2.1.4.2 5GMM-REGISTERED.NORMAL-SERVICE . 72
5.1.3.2.1.4.3 5GMM-REGISTERED.NON-ALLOWED-SERVICE . 72
5.1.3.2.1.4.4 5GMM-REGISTERED.ATTEMPTING-REGISTRATION-UPDATE . 73
5.1.3.2.1.4.5 5GMM-REGISTERED.LIMITED-SERVICE . 73
5.1.3.2.1.4.6 5GMM-REGISTERED.PLMN-SEARCH . 73
5.1.3.2.1.4.7 5GMM-REGISTERED.NO-CELL-AVAILABLE . 73
5.1.3.2.1.4.8 5GMM-REGISTERED.UPDATE-NEEDED . 73
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5 ETSI TS 124 501 V15.5.0 (2019-10)
5.1.3.2.2 5GS update status in the UE . 73
5.1.3.2.3 5GMM sublayer states in the network side . 74
5.1.3.2.3.1 General . 74
5.1.3.2.3.2 5GMM-DEREGISTERED . 74
5.1.3.2.3.3 5GMM-COMMON-PROCEDURE-INITIATED . 74
5.1.3.2.3.4 5GMM-REGISTERED . 74
5.1.3.2.3.5 5GMM-DEREGISTERED-INITIATED . 74
5.1.4 Coordination between 5GMM and EMM . 75
5.1.4.1 General . 75
5.1.4.2 Coordination between 5GMM and EMM with N26 interface . 75
5.1.4.3 Coordination between 5GMM and EMM without N26 interface . 75
5.2 Behaviour of the UE in state 5GMM-DEREGISTERED and state 5GMM-REGISTERED . 76
5.2.1 General . 76
5.2.2 UE behaviour in state 5GMM-DEREGISTERED . 76
5.2.2.1 General . 76
5.2.2.2 Primary substate selection . 76
5.2.2.2.1 Selection of the substate after power on . 76
5.2.2.3 Detailed description of UE behaviour in state 5GMM-DEREGISTERED . 76
5.2.2.3.1 NORMAL-SERVICE . 76
5.2.2.3.2 LIMITED-SERVICE . 77
5.2.2.3.3 ATTEMPTING-REGISTRATION . 77
5.2.2.3.4 PLMN-SEARCH . 77
5.2.2.3.5 NO-SUPI . 77
5.2.2.3.6 NO-CELL-AVAILABLE . 77
5.2.2.3.7 eCALL-INACTIVE . 77
5.2.2.4 Substate when back to state 5GMM-DEREGISTERED from another 5GMM state . 78
5.2.3 UE behaviour in state 5GMM-REGISTERED . 78
5.2.3.1 General . 78
5.2.3.2 Detailed description of UE behaviour in state 5GMM-REGISTERED . 78
5.2.3.2.1 NORMAL-SERVICE . 78
5.2.3.2.2 NON-ALLOWED-SERVICE . 79
5.2.3.2.3 ATTEMPTING-REGISTRATION-UPDATE . 79
5.2.3.2.4 LIMITED-SERVICE . 80
5.2.3.2.5 PLMN-SEARCH . 80
5.2.3.2.6 NO-CELL-AVAILABLE . 80
5.3 General on elementary 5GMM procedures . 80
5.3.1 5GMM modes and N1 NAS signalling connection . 80
5.3.1.1 Establishment of the N1 NAS signalling connection . 80
5.3.1.2 Re-establishment of the N1 NAS signalling connection . 81
5.3.1.3 Release of the N1 NAS signalling connection . 82
5.3.1.4 5GMM-CONNECTED mode with RRC inactive indication . 85
5.3.2 Permanent identifiers . 87
5.3.3 Temporary identities . 87
5.3.4 Registration areas . 88
5.3.5 Service area restrictions . 89
5.3.6 Mobile initiated connection only mode . 90
5.3.7 Handling of the periodic registration update timer and mobile reachable timer . 91
5.3.8 Handling of timer T3502 . 93
5.3.9 Handling of NAS level mobility management congestion control . 93
5.3.10 Handling of DNN based congestion control . 94
5.3.11 Handling of S-NSSAI based congestion control . 94
5.3.12 Handling of local emergency numbers . 94
5.3.12A Handling of local emergency numbers received via 3GPP access and non-3GPP access . 95
5.3.12A.1 General . 95
5.3.12A.2 Receiving a REGISTRATION ACCEPT message via non-3GPP access . 96
5.3.13 Lists of 5GS forbidden tracking areas. 96
5.3.14 List of equivalent PLMNs . 97
5.3.15 Transmission failure abnormal case in the UE .
...