ETSI TS 124 301 V15.8.0 (2020-01)

ETSI TS 124 301 V15.8.0 (2020-01)






TECHNICAL SPECIFICATION
Universal Mobile Telecommunications System (UMTS);
LTE;
5G;
Non-Access-Stratum (NAS)
protocol for Evolved Packet System (EPS);
Stage 3
(3GPP TS 24.301 version 15.8.0 Release 15)

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3GPP TS 24.301 version 15.8.0 Release 15 1 ETSI TS 124 301 V15.8.0 (2020-01)



Reference
RTS/TSGC-0124301vf80
Keywords
5G,LTE,UMTS
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DECT™, PLUGTESTS™, UMTS™ and the ETSI logo are trademarks of ETSI registered for the benefit of its Members.

3GPP™ and LTE™ are trademarks of ETSI registered for the benefit of its Members and
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®
GSM and the GSM logo are trademarks registered and owned by the GSM Association.
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3GPP TS 24.301 version 15.8.0 Release 15 2 ETSI TS 124 301 V15.8.0 (2020-01)
Intellectual Property Rights
Essential patents
IPRs essential or potentially essential to normative deliverables may have been declared to ETSI. The information
pertaining to these essential IPRs, if any, is publicly available for ETSI members and non-members, and can be found
in ETSI SR 000 314: "Intellectual Property Rights (IPRs); Essential, or potentially Essential, IPRs notified to ETSI in
respect of ETSI standards", which is available from the ETSI Secretariat. Latest updates are available on the ETSI Web
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Legal Notice
This Technical Specification (TS) has been produced by ETSI 3rd Generation Partnership Project (3GPP).
The present document may refer to technical specifications or reports using their 3GPP identities. These shall be
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Modal verbs terminology
In the present document "shall", "shall not", "should", "should not", "may", "need not", "will", "will not", "can" and
"cannot" are to be interpreted as described in clause 3.2 of the ETSI Drafting Rules (Verbal forms for the expression of
provisions).
"must" and "must not" are NOT allowed in ETSI deliverables except when used in direct citation.
ETSI

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3GPP TS 24.301 version 15.8.0 Release 15 3 ETSI TS 124 301 V15.8.0 (2020-01)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 19
1 Scope . 20
2 References . 20
3 Definitions and abbreviations . 23
3.1 Definitions . 23
3.2 Abbreviations . 29
4 General . 30
4.1 Overview . 30
4.2 Linkage between the protocols for EPS mobility management and EPS session management . 31
4.2A Handling of NAS signalling low priority indication . 31
4.3 UE mode of operation . 32
4.3.1 General . 32
4.3.2 Change of UE mode of operation . 33
4.3.2.1 General . 33
4.3.2.2 Change of UE's usage setting . 35
4.3.2.3 Change of voice domain preference for E-UTRAN . 36
4.3.2.4 Change or determination of IMS registration status . 37
4.3.2.5 Change of configuration regarding the use of SMS. . 39
4.4 NAS security . 40
4.4.1 General . 40
4.4.2 Handling of EPS security contexts . 40
4.4.2.1 General . 40
4.4.2.2 Establishment of a mapped EPS security context during intersystem handover . 41
4.4.2.3 Establishment of secure exchange of NAS messages . 42
4.4.2.4 Change of security keys . 44
4.4.2.5 Derivation of keys at CS to PS SRVCC handover from A/Gb mode to S1 mode or from Iu mode
to S1 mode . 44
4.4.3 Handling of NAS COUNT and NAS sequence number . 45
4.4.3.1 General . 45
4.4.3.2 Replay protection . 46
4.4.3.3 Integrity protection and verification . 46
4.4.3.4 Ciphering and deciphering . 47
4.4.3.5 NAS COUNT wrap around . 47
4.4.4 Integrity protection of NAS signalling messages. 47
4.4.4.1 General . 47
4.4.4.2 Integrity checking of NAS signalling messages in the UE . 48
4.4.4.3 Integrity checking of NAS signalling messages in the MME . 48
4.4.5 Ciphering of NAS signalling messages . 50
4.5 Disabling and re-enabling of UE's E-UTRA capability . 51
4.6 Applicability of procedures . 53
4.6.1 Relay nodes . 53
4.7 EPS mobility management and EPS session management in NB-S1 mode . 53
4.8 EPS mobility management and EPS session management in WB-S1 mode for IoT . 53
4.9 Disabling and re-enabling of UE's NB-IoT capability . 54
5 Elementary procedures for EPS mobility manage ment . 55
5.1 Overview . 55
5.1.1 General . 55
5.1.2 Types of EMM procedures . 55
5.1.3 EMM sublayer states . 56
5.1.3.1 General . 56
ETSI

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3GPP TS 24.301 version 15.8.0 Release 15 4 ETSI TS 124 301 V15.8.0 (2020-01)
5.1.3.2 EMM sublayer states in the UE. 56
5.1.3.2.1 General . 56
5.1.3.2.2 Main states . 57
5.1.3.2.2.1 EMM-NULL . 57
5.1.3.2.2.2 EMM-DEREGISTERED . 57
5.1.3.2.2.3 EMM-REGISTERED-INITIATED . 57
5.1.3.2.2.4 EMM-REGISTERED . 57
5.1.3.2.2.5 EMM-DEREGISTERED-INITIATED . 57
5.1.3.2.2.6 EMM-TRACKING-AREA-UPDATING-INITIATED . 57
5.1.3.2.2.7 EMM-SERVICE-REQUEST-INITIATED. 57
5.1.3.2.3 Substates of state EMM-DEREGISTERED . 58
5.1.3.2.3.1 General . 58
5.1.3.2.3.2 EMM-DEREGISTERED.NORMAL-SERVICE . 58
5.1.3.2.3.3 EMM-DEREGISTERED.LIMITED-SERVICE . 58
5.1.3.2.3.4 EMM-DEREGISTERED.ATTEMPTING-TO-ATTACH. 59
5.1.3.2.3.5 EMM-DEREGISTERED.PLMN-SEARCH . 59
5.1.3.2.3.6 EMM-DEREGISTERED.NO-IMSI . 59
5.1.3.2.3.7 EMM-DEREGISTERED.ATTACH-NEEDED . 59
5.1.3.2.3.8 EMM-DEREGISTERED.NO-CELL-AVAILABLE . 59
5.1.3.2.3.9 EMM-DEREGISTERED.eCALL-INACTIVE . 59
5.1.3.2.4 Substates of state EMM-REGISTERED . 59
5.1.3.2.4.1 General . 59
5.1.3.2.4.2 EMM-REGISTERED.NORMAL-SERVICE . 59
5.1.3.2.4.3 EMM-REGISTERED.ATTEMPTING-TO-UPDATE . 59
5.1.3.2.4.4 EMM-REGISTERED.LIMITED-SERVICE . 60
5.1.3.2.4.5 EMM-REGISTERED.PLMN-SEARCH . 60
5.1.3.2.4.6 EMM-REGISTERED.UPDATE-NEEDED . 60
5.1.3.2.4.7 EMM-REGISTERED.NO-CELL-AVAILABLE . 60
5.1.3.2.4.8 EMM-REGISTERED.ATTEMPTING-TO-UPDATE-MM . 60
5.1.3.2.4.9 EMM-REGISTERED.IMSI-DETACH-INITIATED . 60
5.1.3.3 EPS update status . 60
5.1.3.4 EMM sublayer states in the MME . 61
5.1.3.4.1 EMM-DEREGISTERED. 61
5.1.3.4.2 EMM-COMMON-PROCEDURE-INITIATED . 61
5.1.3.4.3 EMM-REGISTERED . 61
5.1.3.4.4 EMM-DEREGISTERED-INITIATED . 61
5.1.4 Coordination between EMM and GMM . 62
5.1.5 Coordination between EMM and MM . 63
5.2 Behaviour of the UE in state EMM-DEREGISTERED and state EMM-REGISTERED . 63
5.2.1 General . 63
5.2.2 UE behaviour in state EMM-DEREGISTERED . 63
5.2.2.1 General . 63
5.2.2.2 Primary substate selection . 64
5.2.2.2.1 Selection of the substate after power on . 64
5.2.2.3 Detailed description of UE behaviour in state EMM-DEREGISTERED . 64
5.2.2.3.1 NORMAL-SERVICE . 64
5.2.2.3.2 LIMITED-SERVICE . 64
5.2.2.3.3 ATTEMPTING-TO-ATTACH . 64
5.2.2.3.4 PLMN-SEARCH . 65
5.2.2.3.5 NO-IMSI . 65
5.2.2.3.6 ATTACH-NEEDED . 65
5.2.2.3.7 NO-CELL-AVAILABLE . 65
5.2.2.3.8 eCALL-INACTIVE . 65
5.2.2.4 Substate when back to state EMM-DEREGISTERED from another EMM state . 66
5.2.3 UE behaviour in state EMM-REGISTERED . 66
5.2.3.1 General . 66
5.2.3.2 Detailed description of UE behaviour in state EMM-REGISTERED . 66
5.2.3.2.1 NORMAL-SERVICE . 66
5.2.3.2.2 ATTEMPTING-TO-UPDATE . 67
5.2.3.2.3 LIMITED-SERVICE . 67
5.2.3.2.4 PLMN-SEARCH . 68
5.2.3.2.5 UPDATE-NEEDED . 68
ETSI

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3GPP TS 24.301 version 15.8.0 Release 15 5 ETSI TS 124 301 V15.8.0 (2020-01)
5.2.3.2.6 NO-CELL-AVAILABLE . 68
5.2.3.2.7 ATTEMPTING-TO-UPDATE-MM. 68
5.2.3.2.8 IMSI-DETACH-INITIATED . 68
5.3 General on elementary EMM procedures . 69
5.3.1 EMM modes and NAS signalling connection . 69
5.3.1.1 Establishment of the NAS signalling connection . 69
5.3.1.2 Release of the NAS signalling connection . 70
5.3.1.2.1 General . 70
5.3.1.2.2 UE is using EPS services with control plane CIoT EPS optimization . 72
5.3.1.3 Suspend and resume of the NAS signalling connection . 72
5.3.2 Lists of forbidden tracking areas . 74
5.3.3 List of forbidden PLMNs for attach in S101 mode . 74
5.3.3a Forbidden PLMNs for EPS services . 74
5.3.4 Equivalent PLMNs list. 74
5.3.5 Handling of the periodic tracking area update timer and mobile reachable timer (S1 mode only) . 74
5.3.6 Handling of timer T3402 . 76
5.3.7 Handling of the Local Emergency Numbers List and the Extended Local Emergency Numbers List . 76
5.3.7a Specific requirements for UE configured to use timer T3245 . 78
5.3.7b Specific requirements for UE when receiving non-integrity protected reject messages . 78
5.3.8 Abnormal cases in the UE . 80
5.3.9 Handling of NAS level mobility management congestion control . 81
5.3.9A Handling of congestion control for transport of user data via the control plane . 82
5.3.10 Access class control . 82
5.3.11 Power saving mode . 82
5.3.12 Extended idle-mode DRX cycle . 83
5.3.13 Interaction between power saving mode and extended idle mode DRX cycle . 84
5.3.14 Dedicated core network . 84
5.3.15 CIoT EPS optimizations . 84
5.3.16 Restriction on use of enhanced coverage . 86
5.3.17 Service Gap Control. 86
5.4 EMM common procedures . 87
5.4.1 GUTI reallocation procedure . 87
5.4.1.1 General . 87
5.4.1.2 GUTI reallocation initiation by the network . 88
5.4.1.3 GUTI reallocation completion by the UE . 88
5.4.1.4 GUTI reallocation completion by the network . 88
5.4.1.5 Abnormal cases in the UE . 88
5.4.1.6 Abnormal cases on the network side . 88
5.4.2 Authentication procedure . 90
5.4.2.1 General . 90
5.4.2.2 Authentication initiation by the network . 90
5.4.2.3 Authentication response by the UE . 91
5.4.2.4 Authentication completion by the network . 92
5.4.2.5 Authentication not accepted by the network . 92
5.4.2.6 Authentication not accepted by the UE . 93
5.4.2.7 Abnormal cases . 93
5.4.3 Security mode control procedure . 97
5.4.3.1 General . 97
5.4.3.2 NAS security mode control initiation by the network . 98
5.4.3.3 NAS security mode command accepted by the UE . 99
5.4.3.4 NAS security mode control completion by the network . 101
5.4.3.5 NAS security mode command not accepted by the UE. 101
5.4.3.6 Abnormal cases in the UE . 101
5.4.3.7 Abnormal cases on the network side . 101
5.4.4 Identification procedure .
...