ETSI TS 136 331 V18.3.1 (2024-10)

LTE; Evolved Universal Terrestrial Radio Access (E-UTRA); Radio Resource Control (RRC); Protocol specification (3GPP TS 36.331 version 18.3.1 Release 18)

RTS/TSGR-0236331vi31

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: 17-Oct-2024

Standards Content (Sample)

TECHNICAL SPECIFICATION
LTE;
Evolved Universal Terrestrial Radio Access (E-UTRA);
Radio Resource Control (RRC);
Protocol specification
(3GPP TS 36.331 version 18.3.1 Release 18)

3GPP TS 36.331 version 18.3.1 Release 18 1 ETSI TS 136 331 V18.3.1 (2024-10)

Reference
RTS/TSGR-0236331vi31
Keywords
LTE
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ETSI
3GPP TS 36.331 version 18.3.1 Release 18 2 ETSI TS 136 331 V18.3.1 (2024-10)
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ETSI
3GPP TS 36.331 version 18.3.1 Release 18 3 ETSI TS 136 331 V18.3.1 (2024-10)
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 . 30
3.1 Definitions . 30
3.2 Abbreviations . 33
4 General . 37
4.1 Introduction . 37
4.2 Architecture . 38
4.2.1 UE states and state transitions including inter RAT . 38
4.2.2 Signalling radio bearers . 42
4.3 Services . 43
4.3.1 Services provided to upper layers . 43
4.3.2 Services expected from lower layers . 44
4.4 Functions . 44
4.5 Data available for transmission for NB-IoT . 45
5 Procedures . 45
5.1 General . 45
5.1.1 Introduction. 45
5.1.2 General requirements . 46
5.1.3 Requirements for UE in MR-DC . 47
5.2 System information . 47
5.2.1 Introduction. 47
5.2.1.1 General . 47
5.2.1.2 Scheduling . 48
5.2.1.2a Scheduling for NB-IoT . 49
5.2.1.3 System information validity and notification of changes . 50
5.2.1.4 Indication of ETWS notification . 52
5.2.1.5 Indication of CMAS notification . 52
5.2.1.6 Notification of EAB parameters change . 53
5.2.1.7 Access Barring parameters change in NB-IoT . 53
5.2.1.8 Notification of UAC parameters change . 53
5.2.2 System information acquisition . 54
5.2.2.1 General . 54
5.2.2.2 Initiation . 54
5.2.2.3 System information required by the UE . 54
5.2.2.4 System information acquisition by the UE . 56
5.2.2.5 Essential system information missing . 60
5.2.2.6 Actions upon reception of the MasterInformationBlock message . 61
5.2.2.7 Actions upon reception of the SystemInformationBlockType1 message . 61
5.2.2.8 Actions upon reception of SystemInformation messages . 64
5.2.2.9 Actions upon reception of SystemInformationBlockType2 . 64
5.2.2.10 Actions upon reception of SystemInformationBlockType3 . 66
5.2.2.11 Actions upon reception of SystemInformationBlockType4 . 67
5.2.2.12 Actions upon reception of SystemInformationBlockType5 . 67
5.2.2.13 Actions upon reception of SystemInformationBlockType6 . 68
5.2.2.14 Actions upon reception of SystemInformationBlockType7 . 68
5.2.2.15 Actions upon reception of SystemInformationBlockType8 . 68
5.2.2.16 Actions upon reception of SystemInformationBlockType9 . 69
5.2.2.17 Actions upon reception of SystemInformationBlockType10 . 69
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5.2.2.18 Actions upon reception of SystemInformationBlockType11 . 69
5.2.2.19 Actions upon reception of SystemInformationBlockType12 . 70
5.2.2.20 Actions upon reception of SystemInformationBlockType13 . 71
5.2.2.21 Actions upon reception of SystemInformationBlockType14 . 71
5.2.2.22 Actions upon reception of SystemInformationBlockType15 . 71
5.2.2.23 Actions upon reception of SystemInformationBlockType16 . 71
5.2.2.24 Actions upon reception of SystemInformationBlockType17 . 71
5.2.2.25 Actions upon reception of SystemInformationBlockType18 . 71
5.2.2.26 Actions upon reception of SystemInformationBlockType19 . 72
5.2.2.27 Actions upon reception of SystemInformationBlockType20 . 72
5.2.2.28 Actions upon reception of SystemInformationBlockType21 . 72
5.2.2.29 Actions upon reception of SystemInformationBlockType22-NB . 73
5.2.2.30 Actions upon reception of SystemInformationBlockType23-NB . 73
5.2.2.31 Actions upon reception of SystemInformationBlockType24 . 73
5.2.2.32 Actions upon reception of SystemInformationBlockType25 . 73
5.2.2.33 Actions upon reception of SystemInformationBlockType26 . 73
5.2.2.33a Actions upon reception of SystemInformationBlockType26a . 73
5.2.2.34 Actions upon reception of SystemInformationBlockPos . 74
5.2.2.35 Actions upon reception of SystemInformationBlockType27 . 74
5.2.2.36 Actions upon reception of SystemInformationBlockType28 . 74
5.2.2.37 Actions upon reception of SystemInformationBlockType29 . 74
5.2.2.38 Actions upon reception of SystemInformationBlockType30 . 74
5.2.2.39 Actions upon reception of SystemInformationBlockType31 . 74
5.2.2.40 Actions upon reception of SystemInformationBlockType32 . 74
5.2.2.41 Actions upon reception of SystemInformationBlockType33 . 74
5.2.3 Acquisition of an SI message . 75
5.2.3a Acquisition of an SI message by BL UE or UE in CE or a NB-IoT UE . 75
5.2.3b Acquisition of an SI message from MBMS-dedicated cell . 76
5.3 Connection control . 77
5.3.1 Introduction. 77
5.3.1.1 RRC connection control . 77
5.3.1.2 Security . 79
5.3.1.2a RN security . 81
5.3.1.3 Connected mode mobility . 81
5.3.1.4 Connection control in NB-IoT . 82
5.3.2 Paging . 83
5.3.2.1 General . 83
5.3.2.2 Initiation . 84
5.3.2.3 Reception of the Paging message by the UE . 84
5.3.3 RRC connection establishment . 86
5.3.3.1 General . 86
5.3.3.1a Conditions for establishing RRC Connection for sidelink communication/ discovery/ V2X
sidelink communication/ NR sidelink communication . 89
5.3.3.1b Conditions for initiating EDT . 90
5.3.3.1c Conditions for initiating transmission using PUR . 91
5.3.3.1d Condition for establishing RRC Connection in NT N . 91
5.3.3.2 Initiation . 91
5.3.3.3 Actions related to transmission of RRCConnectionRequest message . 99
5.3.3.3a Actions related to transmission of RRCConnectionResumeRequest message . 100
5.3.3.3b Actions related to transmission of RRCEarlyDataRequest message . 104
5.3.3.3c UE actions upon receiving EDT fallback indication from lower layers . 104
5.3.3.4 Reception of the RRCConnectionSetup by the UE . 105
5.3.3.4a Reception of the RRCConnectionResume by the UE . 111
5.3.3.4b Reception of the RRCEarlyDataComplete by the UE . 116
5.3.3.5 Cell re-selection or cell selection while T300, T302, T303, T305, T306, T308 or T309 is r unni ng . 118
5.3.3.6 T300 expiry . 119
5.3.3.7 T302, T303, T305, T306, or T308 expiry or stop . 120
5.3.3.8 Reception of the RRCConnectionReject by the UE . 121
5.3.3.9 Abortion of RRC connection establishment . 122
5.3.3.9a Abortion of early security reactivation . 123
5.3.3.10 Handling of SSAC related parameters . 123
5.3.3.11 Access barring check. 124
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5.3.3.12 EAB check . 124
5.3.3.13 Access barring check for ACDC . 126
5.3.3.14 Access Barring check for NB-IoT . 126
5.3.3.15 Failure to deliver NAS information in RRCConnectionSetupComplete message . 128
5.3.3.16 Integrity check failure from lower layers while T300 is running . 128
5.3.3.17 Inability to comply with RRCConnectionResume . 129
5.3.3.18 Early security reactivation . 129
5.3.3.19 Timing alignment validation for transmission using PUR . 129
5.3.3.20 Maintenance of PUR occasions . 129
5.3.3.21 UE actions upon indication of out-of-date GNSS position . 130
5.3.3.22 Void. 131
5.3.3.23 UE actions upon detecting discontinuous coverage . 131
5.3.3.24 T390 expiry . 131
5.3.3.25 UE actions upon receiving UL transmission extension indication . 131
5.3.4 Initial security activation . 131
5.3.4.1 General . 131
5.3.4.2 Initiation . 132
5.3.4.3 Reception of the SecurityModeCommand by the UE . 132
5.3.5 RRC connection reconfiguration . 133
5.3.5.1 General . 133
5.3.5.2 Initiation . 133
5.3.5.3 Reception of an RRCConnectionReconfiguration not including the mobilityControlInfo by the
UE . 134
5.3.5.4 Reception of an RRCConnectionReconfiguration including the mobilityControlInfo by the UE
(handover) . 137
5.3.5.5 Reconfiguration failure . 145
5.3.5.6 T304 expiry (handover failure) . 146
5.3.5.7 Void. 148
5.3.5.7a T307 expiry (SCG change failure) . 148
5.3.5.8 Radio Configuration involving full configuration option. 148
5.3.5.9 Conditional reconfiguration . 151
5.3.5.9.1 General . 151
5.3.5.9.2 Conditional reconfiguration removal . 151
5.3.5.9.3 Conditional reconfiguration addition/modification . 151
5.3.5.9.4 Conditional reconfiguration evaluation . 152
5.3.5.9.5 Conditional reconfiguration execution . 153
5.3.5.9.6 VarConditionalReconfiguration remove. 153
5.3.5.9.7 VarConditionalReconfiguration CPC remove . 154
5.3.6 Counter check . 154
5.3.6.1 General . 154
5.3.6.2 Initiation . 154
5.3.6.3 Reception of the CounterCheck message by the UE . 154
5.3.7 RRC connection re-establishment . 155
5.3.7.1 General . 155
5.3.7.1a Condition for re-establishing RRC Connection in NTN . 156
5.3.7.2 Initiation . 156
5.3.7.3 Actions following cell selection while T311 is running . 158
5.3.7.4 Actions related to transmission of RRCConnectionReestablishmentRequest message . 161
5.3.7.5 Reception of the RRCConnectionReestablishment by the UE . 162
5.3.7.6 T311 expiry . 165
5.3.7.7 T301 expiry or selected cell no longer suitable . 165
5.3.7.8 Reception of RRCConnectionReestablishmentReject by the UE . 166
5.3.8 RRC connection release . 166
5.3.8.1 General . 166
5.3.8.2 Initiation . 166
5.3.8.3 Reception of the RRCConnectionRelease by the UE . 166
5.3.8.4 T320 expiry . 170
5.3.8.5 T322 expiry or stop . 170
5.3.8.6 UE actions upon receiving the expiry of DataInactivityTimer . 171
5.3.8.7 UE actions upon entering RRC_INACTIVE . 171
5.3.8.8 T323 expiry . 172
5.3.9 RRC connection release requested by upper layers . 172
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5.3.9.1 General . 172
5.3.9.2 Initiation . 172
5.3.10 Radio resource configuration . 172
5.3.10.0 General . 172
5.3.10.1 SRB addition/ modification . 173
5.3.10.1a SCG RLC bearer addition or reconfiguration for SRBs . 174
5.3.10.2 DRB release . 175
5.3.10.3 DRB addition/ modification . 176
5.3.10.3a1 DC specific DRB addition or reconfiguration . 178
5.3.10.3a2 LWA specific DRB addition or reconfiguration . 180
5.3.10.3a3 LWIP specific DRB addition or reconfiguration. 181
5.3.10.3a4 SCG RLC bearer addition or reconfiguration for DRBs in NE-DC . 182
5.3.10.3a SCell release . 182
5.3.10.3b SCell addition/ modification . 183
5.3.10.3c PSCell addition or modification . 183
5.3.10.3d SCell group release . 184
5.3.10.3e SCell group addition/ modification . 184
5.3.10.4 MAC main reconfiguration . 185
5.3.10.5 Semi-persistent scheduling reconfiguration . 185
5.3.10.6 Physical channel reconfiguration . 185
5.3.10.7 Radio Link Failure Timers and Constants reconfiguration . 187
5.3.10.8 Time domain measurement resource restriction for serving cell . 187
5.3.10.9 Other configuration . 187
5.3.10.10 SCG reconfiguration . 190
5.3.10.11 SCG dedicated resource configuration . 192
5.3.10.12 Reconfiguration SCG or split DRB by drb-ToAddModList . 193
5.3.10.13 Neighbour cell information reconfiguration . 193
5.3.10.14 Void. 194
5.3.10.15 Sidelink dedicated configuration . 194
5.3.10.15a V2X sidelink Communication dedicated configuration . 195
5.3.10.16 T370 expiry . 195
5.3.10.17 SRB release . 196
5.3.10.18 Scheduling Request Configuration for NB-IoT . 196
5.3.10.19 NE-DC release . 196
5.3.11 Radio link failure related actions . 197
5.3.11.1 Detection of physical layer problems in RRC_CONNECTED . 197
5.3.11.1a Early detection of physical layer problems in RRC_CONNECTED . 197
5.3.11.1b Detection of physical layer improvements in RRC_CONNECTED . 197
5.3.11.2 Recovery of physical layer problems . 197
5.3.11.2a Recovery of early detection of physical layer problems . 197
5.3.11.2b Cancellation of physical layer improvements in RRC_CONNECTED . 198
5.3.11.3 Detection of radio link failure . 198
5.3.11.3a Detection of early-out-of-sync event . 201
5.3.11.3b Detection of early-in-sync event . 201
5.3.12 UE actions upon leaving RRC_CONNECTED or RRC_INACTIVE . 201
5.3.13 UE actions upon PUCCH/ SPUCCH/ SRS release request . 204
5.3.13a UE actions upon SR release request for NB-IoT . 204
5.3.13b UE actions upon PUR release request. 205
5.3.14 Proximity indication . 205
5.3.14.1 General . 205
5.3.14.2 Initiation . 205
5.3.14.3 Actions related to transmission of ProximityIndication message. 205
5.3.15 Void . 206
5.3.16 Unified Access Control . 206
5.3.16.1 General . 206
5.3.16.2 Initiation . 206
5.3.16.3 Void. 210
5.3.16.4 T302, T309 expiry or stop (Barring alleviation) . 210
5.3.16.5 Access barring check. 210
5.3.17 RAN notification area update . 211
5.3.17.1 General . 211
5.3.17.2 Initiation . 211
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5.3.17.3 Inter RAT cell reselection or CN type change . 212
5.3.18 T317 expiry . 212
5.4 Inter-RAT mobility. 212
5.4.1 Introduction. 212
5.4.2 Handover to E-UTRA . 213
5.4.2.1 General . 213
5.4.2.2 Initiation . 213
5.4.2.3 Reception of the RRCConnectionReconfiguration by the UE . 213
5.4.2.4 Reconfiguration failure . 217
5.4.2.5 T304 expiry (handover to E-UTRA failure) . 217
5.4.3 Mobility from E-UTRA . 218
5.4.3.1 General . 218
5.4.3.2 Initiation . 218
5.4.3.3 Reception of the MobilityFromEUTRACommand by the UE . 219
5.4.3.4 Successful completion of the mobility from E-UTRA . 220
5.4.3.5 Mobility from E-UTRA failure . 221
5.4.4 Hand
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