ETSI TS 136 331 V15.7.0 (2019-10)

TECHNICAL SPECIFICATION
LTE;
Evolved Universal Terrestrial Radio Access (E-UTRA);
Radio Resource Control (RRC);
Protocol specification
(3GPP TS 36.331 version 15.7.0 Release 15)

3GPP TS 36.331 version 15.7.0 Release 15 1 ETSI TS 136 331 V15.7.0 (2019-10)

Reference
RTS/TSGR-0236331vf70
Keywords
LTE
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ETSI
3GPP TS 36.331 version 15.7.0 Release 15 2 ETSI TS 136 331 V15.7.0 (2019-10)
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ETSI
3GPP TS 36.331 version 15.7.0 Release 15 3 ETSI TS 136 331 V15.7.0 (2019-10)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 22
1 Scope . 23
2 References . 23
3 Definitions, symbols and abbreviations . 27
3.1 Definitions . 27
3.2 Abbreviations . 29
4 General . 33
4.1 Introduction . 33
4.2 Architecture . 34
4.2.1 UE states and state transitions including inter RAT . 34
4.2.2 Signalling radio bearers . 38
4.3 Services . 39
4.3.1 Services provided to upper layers . 39
4.3.2 Services expected from lower layers . 40
4.4 Functions . 40
4.5 Data available for transmission for NB-IoT . 41
5 Procedures . 41
5.1 General . 41
5.1.1 Introduction. 41
5.1.2 General requirements . 42
5.2 System information . 43
5.2.1 Introduction. 43
5.2.1.1 General . 43
5.2.1.2 Scheduling . 44
5.2.1.2a Scheduling for NB-IoT . 45
5.2.1.3 System information validity and notification of changes . 46
5.2.1.4 Indication of ETWS notification . 47
5.2.1.5 Indication of CMAS notification . 48
5.2.1.6 Notification of EAB parameters change . 48
5.2.1.7 Access Barring parameters change in NB-IoT . 48
5.2.2 System information acquisition . 49
5.2.2.1 General . 49
5.2.2.2 Initiation . 49
5.2.2.3 System information required by the UE . 49
5.2.2.4 System information acquisition by the UE . 50
5.2.2.5 Essential system information missing . 54
5.2.2.6 Actions upon reception of the MasterInformationBlock message . 55
5.2.2.7 Actions upon reception of the SystemInformationBlockType1 message . 55
5.2.2.8 Actions upon reception of SystemInformation messages . 57
5.2.2.9 Actions upon reception of SystemInformationBlockType2 . 57
5.2.2.10 Actions upon reception of SystemInformationBlockType3 . 58
5.2.2.11 Actions upon reception of SystemInformationBlockType4 . 59
5.2.2.12 Actions upon reception of SystemInformationBlockType5 . 59
5.2.2.13 Actions upon reception of SystemInformationBlockType6 . 60
5.2.2.14 Actions upon reception of SystemInformationBlockType7 . 61
5.2.2.15 Actions upon reception of SystemInformationBlockType8 . 61
5.2.2.16 Actions upon reception of SystemInformationBlockType9 . 62
5.2.2.17 Actions upon reception of SystemInformationBlockType10 . 62
5.2.2.18 Actions upon reception of SystemInformationBlockType11 . 62
5.2.2.19 Actions upon reception of SystemInformationBlockType12 . 63
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5.2.2.20 Actions upon reception of SystemInformationBlockType13 . 63
5.2.2.21 Actions upon reception of SystemInformationBlockType14 . 64
5.2.2.22 Actions upon reception of SystemInformationBlockType15 . 64
5.2.2.23 Actions upon reception of SystemInformationBlockType16 . 64
5.2.2.24 Actions upon reception of SystemInformationBlockType17 . 64
5.2.2.25 Actions upon reception of SystemInformationBlockType18 . 64
5.2.2.26 Actions upon reception of SystemInformationBlockType19 . 64
5.2.2.27 Actions upon reception of SystemInformationBlockType20 . 65
5.2.2.28 Actions upon reception of SystemInformationBlockType21 . 65
5.2.2.29 Actions upon reception of SystemInformationBlockType22-NB . 65
5.2.2.30 Actions upon reception of SystemInformationBlockType23-NB . 65
5.2.2.31 Actions upon reception of SystemInformationBlockType24 . 65
5.2.2.32 Actions upon reception of SystemInformationBlockType25 . 65
5.2.2.33 Actions upon reception of SystemInformationBlockType26 . 65
5.2.2.34 Actions upon reception of SystemInformationBlockPos . 66
5.2.3 Acquisition of an SI message . 66
5.2.3a Acquisition of an SI message by BL UE or UE in CE or a NB-IoT UE . 67
5.2.3b Acquisition of an SI message from MBMS-dedicated cell . 68
5.3 Connection control . 68
5.3.1 Introduction. 68
5.3.1.1 RRC connection control . 68
5.3.1.2 Security . 70
5.3.1.2a RN security . 72
5.3.1.3 Connected mode mobility . 72
5.3.1.4 Connection control in NB-IoT . 73
5.3.2 Paging . 74
5.3.2.1 General . 74
5.3.2.2 Initiation . 75
5.3.2.3 Reception of the Paging message by the UE . 75
5.3.3 RRC connection establishment . 76
5.3.3.1 General . 76
5.3.3.1a Conditions for establishing RRC Connection for sidelink communication/ discovery/ V2X

sidelink communication . 79
5.3.3.1b Conditions for initiating EDT . 80
5.3.3.2 Initiation . 81
5.3.3.3 Actions related to transmission of RRCConnectionRequest message . 87
5.3.3.3a Actions related to transmission of RRCConnectionResumeRequest message . 88
5.3.3.3b Actions related to transmission of RRCEarlyDataRequest message . 90
5.3.3.3c UE actions upon receiving EDT fallback indication from lower layers . 91
5.3.3.4 Reception of the RRCConnectionSetup by the UE . 91
5.3.3.4a Reception of the RRCConnectionResume by the UE . 94
5.3.3.4b Reception of the RRCEarlyDataComplete by the UE . 98
5.3.3.5 Cell re-selection or cell selection while T300, T302, T303, T305, T306, T308 or T309 is running . 99
5.3.3.6 T300 expiry . 100
5.3.3.7 T302, T303, T305, T306, or T308 expiry or stop . 102
5.3.3.8 Reception of the RRCConnectionReject by the UE . 102
5.3.3.9 Abortion of RRC connection establishment . 104
5.3.3.9a Abortion of UP-EDT . 104
5.3.3.10 Handling of SSAC related parameters . 104
5.3.3.11 Access barring check. 105
5.3.3.12 EAB check . 106
5.3.3.13 Access barring check for ACDC . 107
5.3.3.14 Access Barring check for NB-IoT . 107
5.3.3.15 Failure to deliver NAS information in RRCConnectionSetupComplete message . 109
5.3.3.16 Integrity check failure from lower layers while T300 is running for UP-EDT or
RRC_INACTIVE . 109
5.3.3.17 Inability to comply with RRCConnectionResume . 110
5.3.4 Initial security activation . 110
5.3.4.1 General . 110
5.3.4.2 Initiation . 110
5.3.4.3 Reception of the SecurityModeCommand by the UE . 110
5.3.5 RRC connection reconfiguration . 112
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5.3.5.1 General . 112
5.3.5.2 Initiation . 112
5.3.5.3 Reception of an RRCConnectionReconfiguration not including the mobilityControlInfo by the
UE . 112
5.3.5.4 Reception of an RRCConnectionReconfiguration including the mobilityControlInfo by the UE
(handover) . 115
5.3.5.5 Reconfiguration failure . 121
5.3.5.6 T304 expiry (handover failure) . 121
5.3.5.7 Void. 123
5.3.5.7a T307 expiry (SCG change failure) . 123
5.3.5.8 Radio Configuration involving full configuration option. 123
5.3.6 Counter check . 125
5.3.6.1 General . 125
5.3.6.2 Initiation . 125
5.3.6.3 Reception of the CounterCheck message by the UE . 125
5.3.7 RRC connection re-establishment . 126
5.3.7.1 General . 126
5.3.7.2 Initiation . 127
5.3.7.3 Actions following cell selection while T311 is running . 129
5.3.7.4 Actions related to transmission of RRCConnectionReestablishmentRequest message . 129
5.3.7.5 Reception of the RRCConnectionReestablishment by the UE . 130
5.3.7.6 T311 expiry . 133
5.3.7.7 T301 expiry or selected cell no longer suitable . 134
5.3.7.8 Reception of RRCConnectionReestablishmentReject by the UE . 134
5.3.8 RRC connection release . 134
5.3.8.1 General . 134
5.3.8.2 Initiation . 134
5.3.8.3 Reception of the RRCConnectionRelease by the UE . 134
5.3.8.4 T320 expiry . 137
5.3.8.5 T322 expiry . 137
5.3.8.6 UE actions upon receiving the expiry of DataInactivityTimer . 137
5.3.8.7 UE actions upon entering RRC_INACTIVE . 137
5.3.9 RRC connection release requested by upper layers . 138
5.3.9.1 General . 138
5.3.9.2 Initiation . 138
5.3.10 Radio resource configuration . 138
5.3.10.0 General . 138
5.3.10.1 SRB addition/ modification . 139
5.3.10.1a SCG RLC bearer addition or reconfiguration for SRBs . 141
5.3.10.2 DRB release . 141
5.3.10.3 DRB addition/ modification . 142
5.3.10.3a1 DC specific DRB addition or reconfiguration . 143
5.3.10.3a2 LWA specific DRB addition or reconfiguration . 146
5.3.10.3a3 LWIP specific DRB addition or reconfiguration. 147
5.3.10.3a4 SCG RLC bearer addition or reconfiguration for DRBs in NE-DC . 148
5.3.10.3a SCell release . 148
5.3.10.3b SCell addition/ modification . 148
5.3.10.3c PSCell addition or modification . 149
5.3.10.3d SCell group release . 149
5.3.10.3e SCell group addition/ modification . 149
5.3.10.4 MAC main reconfiguration . 150
5.3.10.5 Semi-persistent scheduling reconfiguration . 151
5.3.10.6 Physical channel reconfiguration . 151
5.3.10.7 Radio Link Failure Timers and Constants reconfiguration . 152
5.3.10.8 Time domain measurement resource restriction for serving cell . 152
5.3.10.9 Other configuration . 152
5.3.10.10 SCG reconfiguration . 155
5.3.10.11 SCG dedicated resource configuration . 157
5.3.10.12 Reconfiguration SCG or split DRB by drb-ToAddModList . 158
5.3.10.13 Neighbour cell information reconfiguration . 158
5.3.10.14 Void. 158
5.3.10.15 Sidelink dedicated configuration . 158
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5.3.10.15a V2X sidelink Communication dedicated configuration . 159
5.3.10.16 T370 expiry . 160
5.3.10.17 SRB release . 160
5.3.10.18 Scheduling Request Configuration for NB-IoT . 161
5.3.10.19 NE-DC release . 161
5.3.11 Radio link failure related actions . 161
5.3.11.1 Detection of physical layer problems in RRC_CONNECTED . 161
5.3.11.1a Early detection of physical layer problems in RRC_CONNECTED . 161
5.3.11.1b Detection of physical layer improvements in RRC_CONNECTED . 161
5.3.11.2 Recovery of physical layer problems . 162
5.3.11.2a Recovery of early detection of physical layer problems . 162
5.3.11.2b Cancellation of physical layer improvements in RRC_CONNECTED . 162
5.3.11.3 Detection of radio link failure . 162
5.3.11.3a Detection of early-out-of-sync event . 164
5.3.11.3b Detection of early-in-sync event . 164
5.3.12 UE actions upon leaving RRC_CONNECTED or RRC_INACTIVE . 165
5.3.13 UE actions upon PUCCH/ SPUCCH/ SRS release request . 166
5.3.13a UE actions upon SR release request for NB-IoT . 167
5.3.14 Proximity indication . 167
5.3.14.1 General . 167
5.3.14.2 Initiation . 167
5.3.14.3 Actions related to transmission of ProximityIndication message. 168
5.3.15 Void . 168
5.3.16 Unified Access Control . 168
5.3.16.1 General . 168
5.3.16.2 Initiation . 168
5.3.16.3 Void. 170
5.3.16.4 T302, T309 expiry or stop (Barring alleviation) . 170
5.3.16.5 Access barring check. 170
5.3.17 RAN notification area update . 171
5.3.17.1 General . 171
5.3.17.2 Initiation . 171
5.3.17.3 Inter RAT cell reselection or CN type change . 171
5.4 Inter-RAT mobility. 172
5.4.1 Introduction. 172
5.4.2 Handover to E-UTRA . 172
5.4.2.1 General . 172
5.4.2.2 Initiation . 172
5.4.2.3 Reception of the RRCConnectionReconfiguration by the UE . 172
5.4.2.4 Reconfiguration failure . 176
5.4.2.5 T304 expiry (handover to E-UTRA failure) . 176
5.4.3 Mobility from E-UTRA . 176
5.4.3.1 General . 176
5.4.3.2 Initiation . 177
5.4.3.3 Reception of the MobilityFromEUTRACommand by the UE . 177
5.4.3.4 Successful completion of the mobility from E-UTRA . 179
5.4.3.5 Mobility from E-UTRA failure . 179
5.4.4 Handover from E-UTRA preparation request (CDMA2000) . 180
5.4.4.1 General . 180
5.4.4.2 Initiation . 180
5.4.4.3 Reception of the HandoverFromEUTRAPreparationRequest by the UE . 180
5.4.5 UL handover preparation transfer (CDMA2000) . 181
5.4.5.1 General . 181
5.4.5.2 Initiation . 181
5.4.5.3 Actions related to transmission of the ULHandoverPreparationTransfer me ssa ge . 181
5.4.5.4 Failure to deliver the ULHandoverPreparationTransfer message . 181
5.4.6 Inter-RAT cell change order to E-UTRAN . 182
5.4.6.1 General . 182
5.4.6.2 Initiation . 182
5.4.6.3 UE fails to complete an inter-RAT cell change order . 182
5.5 Measurements . 182
5.5.1 Introduction. 182
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5.5.2 Measurement configuration . 184
5.5.2.1 General . 184
5.5.2.2 Measurement identity removal . 185
5.5.2.2a Measurement identity autonomous removal . 186
5.5.2.3 Measurement identity addition/ modification . 186
5.5.2.4 Measurement object removal . 187
5.5.2.5 Measurement object addition/ modification . 187
5.5.2.6 Reporting configuration removal . 190
5.5.2.7 Reporting configuration addition/ modification . 190
5.5.2.8 Quantity configuration . 191
5.5.2.9 Measurement gap configuration . 191
5.5.2.9a Measurement gap configuration for RSTD measurements with dense PRS configuration . 192
5.5.2.10 Discovery signals measurement timing configuration . 193
5.5.2.11 RSSI measurement timing configuration . 193
5.5.2.12 Measurement gap sharing configuration . 193
5.5.2.13 NR measurement timing configuration . 194
5.5.3 Performing measurements . 194
5.5.3.1 General . 194
5.5.3.2 Layer 3 filtering . 198
5.5.3.3 Derivation of NR cell quality . 199
5.5.3.4 Derivation of NR beam quality . 199
5.5.4 Measurement report triggering . 199
5.5.4.1 General . 199
5.5.4.2 Event A1 (Serving becomes better than threshold) . 205
5.5.4.3 Event A2 (Serving becomes worse than threshold) . 206
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