ETSI TS 123 502 V15.17.0 (2023-09)

5G; Procedures for the 5G System (5GS) (3GPP TS 23.502 version 15.17.0 Release 15)

RTS/TSGS-0223502vfh0

General Information

• Status: Not Published
• Technical Committee: 3GPP SA 2 - Architecture
• Current Stage: 12 - Citation in the OJ (auto-insert)
• Completion Date: 26-Sep-2023

Standards Content (Sample)

TECHNICAL SPECIFICATION
5G;
Procedures for the 5G System (5GS)
(3GPP TS 23.502 version 15.17.0 Release 15)

3GPP TS 23.502 version 15.17.0 Release 15 1 ETSI TS 123 502 V15.17.0 (2023-09)

Reference
RTS/TSGS-0223502vfh0
Keywords
5G
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ETSI
3GPP TS 23.502 version 15.17.0 Release 15 2 ETSI TS 123 502 V15.17.0 (2023-09)
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ETSI
3GPP TS 23.502 version 15.17.0 Release 15 3 ETSI TS 123 502 V15.17.0 (2023-09)
Contents
Intellectual Property Rights . 2
Legal Notice . 2
Modal verbs terminology . 2
Foreword . 13
1 Scope . 14
2 References . 14
3 Definitions, symbols and abbreviations . 16
3.1 Definitions . 16
3.2 Abbreviations . 16
4 System procedures . 16
4.1 General . 16
4.2 Connection, Registration and Mobility Management procedures . 16
4.2.1 General . 16
4.2.2 Registration Management procedures . 16
4.2.2.1 General . 16
4.2.2.2 Registration procedures . 16
4.2.2.2.1 General . 16
4.2.2.2.2 General Registration . 18
4.2.2.2.3 Registration with AMF re-allocation . 28
4.2.2.3 Deregistration procedures . 30
4.2.2.3.1 General . 30
4.2.2.3.2 UE-initiated Deregistration . 31
4.2.2.3.3 Network-initiated Deregistration . 32
4.2.3 Service Request procedures . 33
4.2.3.1 General . 33
4.2.3.2 UE Triggered Service Request . 33
4.2.3.3 Network Triggered Service Request . 43
4.2.4 UE Configuration Update . 49
4.2.4.1 General . 49
4.2.4.2 UE Configuration Update procedure for access and mobility management related parameters . 49
4.2.4.3 UE Configuration Update procedure for transparent UE Policy delivery . 52
4.2.5 Reachability procedures . 53
4.2.5.1 General . 53
4.2.5.2 UE Reachability Notification Request procedure . 54
4.2.5.3 UE Activity Notification procedure . 55
4.2.6 AN Release . 56
4.2.7 N2 procedures . 58
4.2.7.1 N2 Configuration . 58
4.2.7.2 NGAP UE-TNLA-binding related procedures . 59
4.2.7.2.1 Creating NGAP UE-TNLA-bindings during Registration and Service Request . 59
4.2.7.2.2 Creating NGAP UE-TNLA-bindings during handovers . 59
4.2.7.2.3 Re-Creating NGAP UE-TNLA-bindings subsequent to NGAP UE-TNLA-binding release . 60
4.2.7.2.4 NGAP UE-TNLA-binding update procedure . 60
4.2.7.2.5 NGAP UE-TNLA-binding per UE Release procedure . 60
4.2.7.3 AMF Failure or Planned Maintenance handling procedure . 61
4.2.8 Void . 61
4.2.8a UE Capability Match Request procedure . 61
4.3 Session Management procedures . 62
4.3.1 General . 62
4.3.2 PDU Session Establishment . 63
4.3.2.1 General . 63
4.3.2.2 UE Requested PDU Session Establishment . 63
4.3.2.2.1 Non-roaming and Roaming with Local Breakout . 63
4.3.2.2.2 Home-routed Roaming . 72
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4.3.2.2.3 SMF selection . 76
4.3.2.3 Secondary authorization/authentication by an DN-AAA server during the PDU Session

establishment . 79
4.3.3 PDU Session Modification . 81
4.3.3.1 General . 81
4.3.3.2 UE or network requested PDU Session Modification (non-roaming and roaming with local
breakout) . 81
4.3.3.3 UE or network requested PDU Session Modification (home-routed roaming) . 85
4.3.4 PDU Session Release . 88
4.3.4.1 General . 88
4.3.4.2 UE or network requested PDU Session Release for Non-Roaming and Roaming with Local
Breakout . 88
4.3.4.3 UE or network requested PDU Session Release for Home-routed Roaming . 92
4.3.5 Session continuity, service continuity and UP path management . 94
4.3.5.1 Change of SSC mode 2 PDU Session Anchor with different PDU Sessions . 94
4.3.5.2 Change of SSC mode 3 PDU Session Anchor with multiple PDU Sessions . 95
4.3.5.3 Change of SSC mode 3 PDU Session Anchor with IPv6 Multi-homed PDU Session . 96
4.3.5.4 Addition of additional PDU Session Anchor and Branching Point or UL CL . 98
4.3.5.5 Removal of additional PDU Session Anchor and Branching Point or UL CL . 100
4.3.5.6 Change of additional PDU Session Anchor for IPv6 multi-homing or UL CL . 101
4.3.5.7 Simultaneous change of Branching Point or UL CL and additional PSA for a PDU Session. 103
4.3.6 Application Function influence on traffic routing . 105
4.3.6.1 General . 105
4.3.6.2 Processing AF requests to influence traffic routing for Sessions not identified by an UE address . 106
4.3.6.3 Notification of User Plane Management Events . 107
4.3.6.4 Transferring an AF request targeting an individual UE address to the relevant PCF. 109
4.3.7 CN-initiated selective deactivation of UP connection of an existing PDU Session . 110
4.4 SMF and UPF interactions . 111
4.4.1 N4 session management procedures . 111
4.4.1.1 General . 111
4.4.1.2 N4 Session Establishment procedure . 111
4.4.1.3 N4 Session Modification procedure . 112
4.4.1.4 N4 Session Release procedure . 113
4.4.2 N4 Reporting Procedures . 113
4.4.2.1 General . 113
4.4.2.2 N4 Session Level Reporting Procedure . 113
4.4.3 N4 Node Level Procedures . 114
4.4.3.1 N4 Association Setup Procedure . 114
4.4.3.2 N4 Association Update Procedure . 115
4.4.3.3 N4 Association Release Procedure . 115
4.4.3.4 N4 Report Procedure . 116
4.4.3.5 N4 PFD management Procedure . 116
4.4.4 SMF Pause of Charging procedure . 117
4.5 User Profile management procedures . 118
4.5.1 Subscriber Data Update Notification to AMF . 118
4.5.2 Session Management Subscriber Data Update Notification to SMF . 119
4.5.3 Purge of subscriber data in AMF . 119
4.6 Security procedures . 120
4.7 ME Identity check procedure . 120
4.8 RAN-CN interactions . 120
4.8.1 Connection Inactive procedure . 120
4.8.2 Connection Resume procedure . 120
4.8.3 N2 Notification procedure . 121
4.9 Handover procedures . 122
4.9.1 Handover procedures in 3GPP access . 122
4.9.1.1 General . 122
4.9.1.2 Xn based inter NG-RAN handover . 122
4.9.1.2.1 General . 122
4.9.1.2.2 Xn based inter NG-RAN handover without User Plane function re-allocation . 123
4.9.1.2.3 Xn based inter NG-RAN handover with insertion of intermediate UPF . 125
4.9.1.2.4 Xn based inter NG-RAN handover with re-allocation of intermediate UPF . 127
4.9.1.3 Inter NG-RAN node N2 based handover . 128
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4.9.1.3.1 General . 128
4.9.1.3.2 Preparation phase. 130
4.9.1.3.3 Execution phase . 135
4.9.1.4 Inter NG-RAN node N2 based handover, Cancel . 138
4.9.2 Handover of a PDU Session procedure between 3GPP and untrusted non-3GPP access . 139
4.9.2.1 Handover of a PDU Session procedure from untrusted non-3GPP to 3GPP access (non-roaming
and roaming with local breakout) . 139
4.9.2.2 Handover of a PDU Session procedure from 3GPP to untrusted non-3GPP access (non-roaming

and roaming with local breakout) . 139
4.9.2.3 Handover of a PDU Session procedure from untrusted non-3GPP to 3GPP access (home routed
roaming) . 140
4.9.2.3.1 The target AMF is in the PLMN of the N3IWF . 140
4.9.2.3.2 The target AMF is not in the PLMN of the N3IWF (i.e. N3IWF in HPLMN) . 141
4.9.2.4 Handover of a PDU Session procedure from 3GPP to untrusted non-3GPP access (home routed

roaming) . 141
4.9.2.4.1 The selected N3IWF is in the registered PLMN . 141
4.9.2.4.2 The UE is roaming and the selected N3IWF is in the home PLMN . 142
4.10 NG-RAN Location reporting procedures . 143
4.11 System interworking procedures with EPC . 144
4.11.0 General . 144
4.11.0a Impacts to EPS Procedures . 144
4.11.0a.1 General . 144
4.11.0a.2 Interaction with PCC . 144
4.11.0a.3 Mobility Restrictions . 145
4.11.0a.4 PGW Selection . 145
4.11.0a.5 PDN Connection Establishment . 145
4.11.1 N26 based Interworking Procedures . 146
4.11.1.1 General . 146
4.11.1.2 Handover procedures . 147
4.11.1.2.1 5GS to EPS handover using N26 interface . 147
4.11.1.2.2 EPS to 5GS handover using N26 interface . 151
4.11.1.2.3 Handover Cancel . 157
4.11.1.3 Idle Mode Mobility procedures . 158
4.11.1.3.1 General . 158
4.11.1.3.2 5GS to EPS Idle mode mobility using N26 interface . 159
4.11.1.3.3 EPS to 5GS Mobility Registration Procedure (Idle and Connected State) using N26 interface . 161
4.11.1.4 Procedures for EPS bearer ID allocation . 165
4.11.1.4.1 EPS bearer ID allocation . 165
4.11.1.4.2 EPS bearer ID transfer . 168
4.11.1.4.3 EPS bearer ID revocation . 169
4.11.1.5 Impacts to EPS Procedures . 170
4.11.1.5.1 General . 170
4.11.1.5.2 E-UTRAN Initial Attach . 170
4.11.1.5.3 Tracking Area Update . 171
4.11.1.5.4 Session Management . 171
4.11.1.5.5 5GS to EPS handover using N26 interface . 173
4.11.1.6 EPS interworking information storing Procedure . 174
4.11.2 Interworking procedures without N26 interface . 174
4.11.2.1 General . 174
4.11.2.2 5GS to EPS Mobility . 174
4.11.2.3 EPS to 5GS Mobility . 177
4.11.2.4 Impacts to EPS Procedures . 179
4.11.2.4.1 E-UTRAN Attach . 179
4.11.2.4.2 Session Management . 181
4.11.2.4.3 Initial Attach on S2b . 181
4.11.3 Handover procedures between EPS and 5GC-N3IWF . 182
4.11.3.1 Handover from EPS to 5GC-N3IWF . 182
4.11.3.2 Handover from 5GC-N3IWF to EPS . 182
4.11.4 Handover procedures between EPC/ePDG and 5GS . 183
4.11.4.1 Handover from EPC/ePDG to 5GS . 183
4.11.4.2 Handover from 5GS to EPC/ePDG . 184
4.11.5 Impacts to 5GC Procedures . 185
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4.11.5.1 General . 185
4.11.5.2 Registration procedure . 185
4.11.5.3 UE Requested PDU Session Establishment procedure . 185
4.11.5.4 UE or Network Requested PDU Session Modification procedure . 186
4.11.5.5 Xn based inter NG-RAN handover . 186
4.11.5.6 Inter NG-RAN node N2 based handover . 186
4.12 Procedures for non-3GPP access . 186
4.12.1 General . 186
4.12.2 Registration via Untrusted non-3GPP Access . 187
4.12.2.1 General . 187
4.12.2.2 Registration procedure for untrusted non-3GPP access . 187
4.12.2.3 Emergency Registration for untrusted non-3GPP Access . 190
4.12.3 Deregistration procedure for untrusted non-3gpp access . 191
4.12.4 N2 procedures via Untrusted non-3GPP Access . 191
4.12.4.1 Service Request procedures via Untrusted non-3GPP Access . 191
4.12.4.2 Procedure for the UE context release in the N3IWF . 192
4.12.4.3 CN-initiated selective deactivation of UP connection of an existing PDU Session associated with
Untrusted non-3GPP Access . 194
4.12.5 UE Requested PDU Session Establishment via Untrusted non-3GPP Access. 194
4.12.6 UE or Network Requested PDU Session Modification via Untrusted non-3GPP access . 196
4.12.7 UE or network Requested PDU Session Release via Untrusted non-3GPP access. 197
4.12.8 Mobility from a non-geographically selected AMF to a geographically selected AMF . 199
4.13 Specific services . 200
4.13.1 General . 200
4.13.2 Application Triggering . 200
4.13.2.1 General . 200
4.13.2.2 The procedure of "Application Triggering" Service . 201
4.13.3 SMS over NAS procedures . 203
4.13.3.1 Registration procedures for SMS over NAS . 203
4.13.3.2 Deregistration procedures for SMS over NAS . 204
4.13.3.3 MO SMS over NAS in CM-IDLE (baseline) . 205
4.13.3.4 Void. 206
4.13.3.5 MO SMS over NAS in CM-CONNECTED . 206
4.13.3.6 MT SMS over NAS in CM-IDLE state via 3GPP access. 207
4.13.3.7 MT SMS over NAS in CM-CONNECTED state via 3GPP access. 208
4.13.3.8 MT SMS over NAS via non-3GPP access . 208
4.13.3.9 Unsuccessful Mobile terminating SMS delivery attempt . 208
4.13.4 Emergency Services . 209
4.13.4.1 General . 209
4.13.4.2 Emergency Services Fallback . 209
4.13.5 Location Services procedures . 211
4.13.5.1 5GC-NI-LR Procedure . 211
4.13.5.2 5GC-MT-LR Procedure without UDM Query . 212
4.13.5.3 5GC-MT-LR Procedure . 213
4.13.5.4 UE Assisted and UE Based Positioning Procedure . 214
4.13.5.5 Network Assisted Positioning Procedure . 215
4.13.5.6 Obtaining Non-UE Associated Network Assistance Data . 216
4.13.5.7 Location continuity for Handover of an Emergency session from NG-RAN . 216
4.13.6 Support of IMS Voice . 218
4.13.6.1 EPS fallback for IMS voice . 218
4.13.6.2 Inter RAT Fallback in 5GC for IMS voice . 220
4.14 Support for Dual Connectivity . 221
4.14.1 RAN Initiated QoS Flow Mobility . 221
4.15 Network Exposure . 223
4.15.1 General . 223
4.15.2 External Exposure of Network Capabilities . 224
4.15.3 Event Exposure using NEF . 224
4.15.3.1 Monitoring Events . 224
4.15.3.2 Information flows . 227
4.15.3.2.1 AMF service operations information flow. 227
4.15.3.2.2 UDM service operations information flow . 227
4.15.3.2.3 NEF service operations information flow . 229
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4.15.3.2.4 Exposure with bulk subscription . 231
4.15.4 Core Network Internal Event Exposure . 232
4.15.4.1 General . 232
4.15.4.2 Exposure of Mobility Events from AMF . 232
4.15.5 Void . 233
4.15.6 External Parameter Provisioning . 233
4.15.6.1 General . 233
4.15.6.2 NEF service operations information flow . 233
4.15.6.3 Expected UE Behaviour parameters. 234
4.15.6.4 Set a chargeable party at AF session setup . 235
4.15.6.5 Change the chargeable party during the session. 236
4.15.6.6 Setting up an AF session with required QoS procedure . 237
4.16 Procedures and flows for Policy Framework . 238
4.16.1 AM Policy Association Establishment . 238
4.16.1.1 General . 238
4.16.1.2 AM Policy Association Establishment with new Selected PCF . 238
4.16.1.3 Void. 239
4.16.2 AM Policy Association Modific
...