ETSI TS 138 331 V17.5.0 (2023-07)

5G; NR; Radio Resource Control (RRC); Protocol specification (3GPP TS 38.331 version 17.5.0 Release 17)

RTS/TSGR-0238331vh50

General Information

• Status: Not Published
• Technical Committee: 3GPP RAN 2 - Radio layer 2 specification and Radio layer 3 RR specification
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 27-Jul-2023

Standards Content (Sample)

ETSI TS 138 331 V17.5.0 (2023-07)






TECHNICAL SPECIFICATION
5G;
NR;
Radio Resource Control (RRC);
Protocol specification
(3GPP TS 38.331 version 17.5.0 Release 17)

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3GPP TS 38.331 version 17.5.0 Release 17 1 ETSI TS 138 331 V17.5.0 (2023-07)

Reference
RTS/TSGR-0238331vh50
Keywords
5G
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ETSI

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3GPP TS 38.331 version 17.5.0 Release 17 2 ETSI TS 138 331 V17.5.0 (2023-07)
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ETSI

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3GPP TS 38.331 version 17.5.0 Release 17 3 ETSI TS 138 331 V17.5.0 (2023-07)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 24
1 Scope . 25
2 References . 25
3 Definitions, symbols and abbreviations . 28
3.1 Definitions . 28
3.2 Abbreviations . 30
4 General . 32
4.1 Introduction . 32
4.2 Architecture . 33
4.2.1 UE states and state transitions including inter RAT . 33
4.2.2 Signalling radio bearers . 36
4.3 Services . 36
4.3.1 Services provided to upper layers . 36
4.3.2 Services expected from lower layers . 37
4.4 Functions . 37
5 Procedures . 38
5.1 General . 38
5.1.1 Introduction. 38
5.1.2 General requirements . 38
5.1.3 Requirements for UE in MR-DC . 39
5.2 System information . 39
5.2.1 Introduction. 39
5.2.2 System information acquisition . 40
5.2.2.1 General UE requirements . 40
5.2.2.2 SIB validity and need to (re)-acquire SIB . 41
5.2.2.2.1 SIB validity . 41
5.2.2.2.2 SI change indication and PWS notification . 42
5.2.2.3 Acquisition of System Information . 43
5.2.2.3.1 Acquisition of MIB and SIB1 . 43
5.2.2.3.2 Acquisition of an SI message . 44
5.2.2.3.3 Request for on demand system information . 46
5.2.2.3.3a Request for on demand positioning system information . 47
5.2.2.3.4 Actions related to transmission of RRCSystemInfoRequest message . 48
5.2.2.3.5 Acquisition of SIB(s) or posSIB(s) in RRC_CONNECTED . 49
5.2.2.3.6 Actions related to transmission of DedicatedSIBRequest message . 49
5.2.2.4 Actions upon receipt of System Information . 50
5.2.2.4.1 Actions upon reception of the MIB . 50
5.2.2.4.2 Actions upon reception of the SIB1 . 50
5.2.2.4.3 Actions upon reception of SIB2 . 54
5.2.2.4.4 Actions upon reception of SIB3 . 55
5.2.2.4.5 Actions upon reception of SIB4 . 55
5.2.2.4.6 Actions upon reception of SIB5 . 56
5.2.2.4.7 Actions upon reception of SIB6 . 56
5.2.2.4.8 Actions upon reception of SIB7 . 56
5.2.2.4.9 Actions upon reception of SIB8 . 57
5.2.2.4.10 Actions upon reception of SIB9 . 58
5.2.2.4.11 Actions upon reception of SIB10 . 58
5.2.2.4.12 Actions upon reception of SIB11 . 58
5.2.2.4.13 Actions upon reception of SIB12 . 58
5.2.2.4.14 Actions upon reception of SIB13 . 60
ETSI

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3GPP TS 38.331 version 17.5.0 Release 17 4 ETSI TS 138 331 V17.5.0 (2023-07)
5.2.2.4.15 Actions upon reception of SIB14 . 60
5.2.2.4.16 Actions upon reception of SIBpos . 60
5.2.2.4.17 Actions upon reception of SIB15 . 60
5.2.2.4.18 Actions upon reception of SIB16 . 60
5.2.2.4.19 Actions upon reception of SIB17 . 60
5.2.2.4.20 Actions upon reception of SIB18 . 60
5.2.2.4.21 Actions upon reception of SIB19 . 60
5.2.2.4.22 Actions upon reception of SIB20 . 61
5.2.2.4.23 Actions upon reception of SIB21 . 61
5.2.2.5 Essential system information missing . 61
5.2.2.6 T430 expiry . 61
5.3 Connection control . 62
5.3.1 Introduction. 62
5.3.1.1 RRC connection control . 62
5.3.1.2 AS Security . 63
5.3.2 Paging . 64
5.3.2.1 General . 64
5.3.2.2 Initiation . 64
5.3.2.3 Reception of the Paging message by the UE or PagingRecord by the L2 U2N Remote UE . 64
5.3.3 RRC connection establishment . 66
5.3.3.1 General . 66
5.3.3.1a Conditions for establishing RRC Connection for NR sidelink communication/discovery/V2X
sidelink communication . 66
5.3.3.2 Initiation . 67
5.3.3.3 Actions related to transmission of RRCSetupRequest mes sa ge . 68
5.3.3.4 Reception of the RRCSetup by the UE . 68
5.3.3.5 Reception of the RRCReject by the UE . 72
5.3.3.6 Cell re-selection or cell selection or relay (re)selection while T390, T300 or T302 is running (UE
in RRC_IDLE) . 72
5.3.3.7 T300 expiry . 72
5.3.3.8 Abortion of RRC connection establishment . 74
5.3.4 Initial AS security activation . 74
5.3.4.1 General . 74
5.3.4.2 Initiation . 75
5.3.4.3 Reception of the SecurityModeCommand by the UE . 75
5.3.5 RRC reconfiguration . 76
5.3.5.1 General . 76
5.3.5.2 Initiation . 77
5.3.5.3 Reception of an RRCReconfiguration by the UE . 77
5.3.5.4 Secondary cell group release . 89
5.3.5.5 Cell Group configuration . 89
5.3.5.5.1 General . 89
5.3.5.5.2 Reconfiguration with sync . 90
5.3.5.5.3 RLC bearer release . 92
5.3.5.5.4 RLC bearer addition/modification . 92
5.3.5.5.5 MAC entity configuration . 93
5.3.5.5.6 RLF Timers & Constants configuration . 94
5.3.5.5.7 SpCell Configuration . 94
5.3.5.5.8 SCell Release . 96
5.3.5.5.9 SCell Addition/Modification . 96
5.3.5.5.10 BH RLC channel release . 97
5.3.5.5.11 BH RLC channel addition/modification . 97
5.3.5.5.12 Uu Relay RLC channel release . 97
5.3.5.5.13 Uu Relay RLC channel addition/modification . 97
5.3.5.6 Radio Bearer configuration . 98
5.3.5.6.1 General . 98
5.3.5.6.2 SRB release . 98
5.3.5.6.3 SRB addition/modification . 98
5.3.5.6.4 DRB release . 100
5.3.5.6.5 DRB addition/modification . 101
5.3.5.6.6 Multicast MRB release . 104
5.3.5.6.7 Multicast MRB addition/modification . 104
ETSI

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3GPP TS 38.331 version 17.5.0 Release 17 5 ETSI TS 138 331 V17.5.0 (2023-07)
5.3.5.7 AS Security key update . 105
5.3.5.8 Reconfiguration failure . 106
5.3.5.8.1 Void . 106
5.3.5.8.2 Inability to comply with RRCReconfiguration . 106
5.3.5.8.3 T304 expiry (Reconfiguration with sync Failure) or T420 expiry (Path switch failure) . 108
5.3.5.9 Other configuration . 109
5.3.5.9a MUSIM gap configuration . 113
5.3.5.10 MR-DC release . 114
5.3.5.11 Full configuration . 114
5.3.5.12 BAP configuration . 116
5.3.5.12a IAB Other Configuration . 117
5.3.5.12a.1 IP address management . 117
5.3.5.12a.1.1 IP Address Release . 117
5.3.5.12a.1.2 IP Address Addition/Modification . 117
5.3.5.13 Conditional Reconfiguration . 118
5.3.5.13.1 General . 118
5.3.5.13.2 Conditional reconfiguration removal . 119
5.3.5.13.3 Conditional reconfiguration addition/modification . 119
5.3.5.13.4 Conditional reconfiguration evaluation . 119
5.3.5.13.4a Conditional reconfiguration evaluation of SN initiated inter-SN CPC for EN-DC . 121
5.3.5.13.5 Conditional reconfiguration execution . 121
5.3.5.13a SCG activation . 122
5.3.5.13b SCG deactivation . 122
5.3.5.13b1 SCG activation without SN message . 122
5.3.5.13c FR2 UL gap configuration . 123
5.3.5.13d Application layer measurement configuration . 123
5.3.5.14 Sidelink dedicated configuration . 124
5.3.5.15 L2 U2N Relay UE configuration . 126
5.3.5.15.1 General . 126
5.3.5.15.2 L2 U2N Remote UE Release . 127
5.3.5.15.3 L2 U2N Remote UE Addition/Modification . 127
5.3.5.16 L2 U2N Remote UE configuration . 127
5.3.6 Counter check . 128
5.3.6.1 General . 128
5.3.6.2 Initiation . 128
5.3.6.3 Reception of the CounterCheck message by the UE . 128
5.3.7 RRC connection re-establishment .
...