Content for TR 23.700-41 Word version: 18.0.0
5 Key Issues p. 12
5.1 Key Issue #1: Support of Network Slice Service continuity p. 12
5.1.1 Description p. 12
5.2 Key Issue #2: Support of providing VPLMN network slice information to a roaming UE p. 13
5.2.1 Description p. 13
5.3 Key Issue #3: Network Slice Area of Service for services not mapping to existing TAs boundaries and Temporary network slices p. 13
5.3.1 Description p. 13
5.4 Key Issue #4: Support of NSAC involving multi service Area p. 14
5.4.1 Description p. 14
5.5 Key Issue #5: Improved support of RAs including TAs supporting Rejected S-NSSAIs p. 14
5.6 Key Issue #6: Improved network control of the UE behaviour p. 15
5.6.1 Description p. 15
6 Solutions p. 16
6.0 Mapping of Solutions to Key Issues p. 16
6.1 Solution #1: Additional S-NSSAI associated with the PDU session p. 18
6.1.1 Introduction p. 18
6.1.2 Functional Description p. 18
6.1.3 Procedures p. 19
6.1.3.1 Additional S-NSSAI handling during Handover Procedure p. 19
6.1.3.2 Additional S-NSSAI handling during PDU Session Establishment Procedure p. 19
6.1.4 Impacts on existing entities and interfaces p. 20
6.2 Solution #2: Slice Re-mapping Capabilities for Network Slice Service Continuity p. 21
6.2.1 Introduction p. 21
6.2.2 Functional Description p. 21
6.2.3 Procedures p. 21
6.2.3.1 General p. 21
6.2.3.2 Registration p. 21
6.2.3.3 Change of S-NSSAI of a PDU Session p. 22
6.2.3.4 AMF-triggered PDU Session Modification to change of S-NSSAI of PDU Session p. 23
6.2.4 Impacts on services, entities and interfaces p. 24
6.3 Solution #3: Support of Network Slice Service continuity using a SSC mode 3 type of Service continuity p. 24
6.3.1 Introduction p. 24
6.3.2 Functional Description p. 24
6.3.3 Procedures p. 24
6.3.4 Impacts on services, entities and interfaces p. 26
6.4 Solution #4: PDU Session on compatible network slice p. 26
6.4.1 Introduction p. 26
6.4.2 Functional description p. 27
6.4.3 Procedures p. 27
6.4.4 Impacts on services, entities and interfaces p. 27
6.5 Solution #5: PDU session handover to a target CN with an alternative S-NSSAI support p. 28
6.5.1 Introduction p. 28
6.5.2 Functional description p. 28
6.5.3 Procedures p. 28
6.5.4 Impacts on services, entities and interfaces p. 29
6.6 Solution #6: Extended SoR VPLMN Slice Information transfer to UEs p. 29
6.6.1 Introduction p. 29
6.6.2 Functional Description p. 29
6.6.3 Procedures p. 30
6.6.4 Impacts on Existing Nodes and Functionality p. 34
6.7 Solution #7: Enabling awareness of Network Slice availability in VPLMNs p. 34
6.7.1 Introduction p. 34
6.7.2 Functional Description p. 34
6.7.3 Procedures p. 35
6.7.3.1 Option 1 - UE's USIM is NOT configured to receive a Slice-Aware SoR p. 35
6.7.3.2 Option 2 - UE's USIM is configured to receive a Slice-Aware SoR p. 36
6.7.4 Impacts on services, entities and interfaces p. 36
6.8 Solution #8: Gracefully network slice termination p. 37
6.8.1 Introduction p. 37
6.8.2 Functional Description p. 38
6.8.3 Procedures p. 38
6.8.4 Impacts on services, entities and interfaces p. 40
6.9 Solution #9: Support of a Network Slice with an AoS not matching existing TA boundaries. p. 41
6.9.1 Introduction p. 41
6.9.2 Description p. 41
6.9.3 Procedures p. 42
6.9.4 Impacts on services, entities and interfaces p. 44
6.10 Solution #10: Associating a validity timer with a temporary slice p. 45
6.10.1 Introduction p. 45
6.10.2 Procedures p. 46
6.10.3 Impacts on services, entities and interfaces p. 46
6.11 Solution #11: Enabling UEs to Request S-NSSAIs not uniformly available p. 47
6.11.1 Introduction p. 47
6.11.2 Functional Description p. 47
6.11.3 Procedures p. 48
6.11.3.1 Registration Procedure p. 48
6.11.3.2 UE Configuration Update Procedure p. 49
6.11.3.3 UE Requested PDU Session Establishment Procedure p. 49
6.11.3.4 Service Request p. 49
6.11.3.5 PDU Session Release p. 49
6.11.4 Impacts on services, entities and interfaces p. 49
6.12 Solution #12: Solution for Centralized Counting for Multiple Service Areas and 5GS-EPS Interworking p. 50
6.12.1 Description p. 50
6.12.2 Procedures p. 51
6.12.2.1 UE Registration Admission p. 51
6.12.2.2 Roaming p. 52
6.12.2.3 UE PDU Session Admission p. 52
6.12.2.4 Discovery of Central NSACF p. 53
6.12.3 Impacts on services, entities and interfaces p. 53
6.13 Solution #13: Hierarchical NSACF Architecture for Maximum UE/PDU Session number control p. 54
6.13.1 Introduction p. 54
6.13.2 Functional Description p. 54
6.13.3 Procedures p. 56
6.13.3.1 Registration management Procedures p. 56
6.13.3.2 PDU Session management Procedures p. 58
6.13.3.3 Redistribution of local maximum number p. 59
6.13.3.4 Session continuity handling p. 59
6.13.3.5 HPLMN control and EPS counting support p. 60
6.13.4 Impacts on services, entities and interfaces p. 60
6.14 Solution #14: Maximum Number Distribution in multiple NSACFs p. 60
6.14.1 Introduction p. 60
6.14.2 Functional Description p. 61
6.14.3 Procedure p. 61
6.14.4 Impacts on services, entities and interfaces p. 61
6.15 Solution #15: Service continuity in case of Network Slice instance overload p. 62
6.15.1 Introduction p. 62
6.15.2 Functional Description p. 62
6.15.3 Procedures p. 63
6.15.4 Impacts on services, entities and interfaces p. 63
6.16 Solution #16: UE assisted slice based VPLMN prioritization for Extended SoR p. 64
6.16.1 Introduction p. 64
6.16.2 High Level Description p. 64
6.16.3 Procedures p. 64
6.16.4 Impacts on services, entities and interfaces p. 66
6.17 Solution #17: Slice based VPLMN Selection Policy p. 66
6.17.1 Introduction p. 66
6.17.2 Functional Description p. 66
6.17.3 Procedures p. 67
6.17.4 Impacts on services, entities and interfaces p. 68
6.18 Solution #18: Sending rejected NSSAI to the UDM to assist the UDM to steer the UE to the PLMN supporting rejected NSSAI p. 68
6.18.1 Introduction p. 68
6.18.2 Procedures p. 68
6.18.3 Impacts on services, entities and interfaces p. 69
6.19 Solution #19: Configuring the UE with network slice aware preferred PLMNs lists p. 70
6.19.1 Introduction p. 70
6.19.2 Functional Description p. 70
6.19.3 Procedures p. 71
6.19.4 Impacts on services, entities and interfaces p. 73
6.20 Solution #20: PLMN Selection following existing SoR information p. 73
6.20.1 Introduction p. 73
6.20.2 Functional Description p. 73
6.20.3 Procedures p. 74
6.20.4 Impacts on services, entities and interfaces p. 74
6.21 Solution #21: Temporary slice based on URSP p. 75
6.21.1 Introduction p. 75
6.21.2 Functional Description p. 75
6.21.3 Procedures p. 75
6.21.4 Impacts on services, entities and interfaces p. 75
6.22 Solution #22: Enabling graceful slice termination with support of UE policies p. 76
6.22.1 Introduction p. 76
6.22.2 Functional Description p. 76
6.22.3 Procedures p. 77
6.22.4 Impacts on services, entities and interfaces p. 77
6.23 Solution #23: UE registration for conditional network slices p. 77
6.23.1 Introduction p. 77
6.23.2 Functional description p. 77
6.23.3 Procedures p. 78
6.23.4 Impacts on services, entities and interfaces p. 79
6.24 Solution #24: On the handling of temporary network slices p. 79
6.24.1 Introduction p. 79
6.24.2 Functional Description p. 79
6.24.3 Procedures p. 80
6.24.4 Impacts on services, entities and interfaces p. 84
6.25 Solution #25: Handling Rejected S-NSSAIs in some TAs of RA p. 85
6.25.1 Key Issue mapping p. 85
6.25.2 Functional Description p. 85
6.25.3 Procedures p. 86
6.25.4 Impacts on services, entities and interfaces p. 87
6.26 Solution #26: Multiple areas and resource partitioning p. 87
6.26.1 Introduction p. 87
6.26.2 Functional Description p. 88
6.26.2.1 Support of multiple areas p. 88
6.26.2.2 Reducing resources for cells outside service area p. 88
6.26.3 Procedures p. 90
6.26.4 Impacts on services, entities and interfaces p. 91
6.27 Solution #27: Exception to the rejected NSSAI handling p. 91
6.27.1 Introduction p. 91
6.27.2 Functional Description p. 91
6.27.3 Procedures p. 92
6.27.4 Impacts on services, entities and interfaces p. 93
6.28 Solution #28: Support of network slices with TA granularity within a RA p. 93
6.28.1 Functional Description p. 93
6.28.2 Procedures p. 94
6.28.3 Impacts on Existing Nodes and Functionality p. 94
6.29 Solution #29: On handling S-NSSAIs not supported in certain TAs of a RA during a registration p. 94
6.29.1 Introduction p. 94
6.29.2 Functional Description p. 95
6.29.3 Procedures p. 96
6.29.3.1 Indication to UE of TAIs where the rejected S-NSSAI is supported (or is not supported) in the RA p. 96
6.29.3.2 Indication to UE of Allowed NSSAI in RA and of Partially Allowed S-NSSAIs in RA with TAIs of RA where the Partially Allowed S-NSSAIs is supported. p. 97
6.29.4 Impacts on services, entities and interfaces p. 106
6.30 Solution #30: Rejected S-NSSAI with new cause value p. 107
6.30.1 Introduction p. 107
6.30.2 Functional Description p. 107
6.30.3 Procedure p. 107
6.30.4 Impacts on services, entities and interfaces p. 108
6.31 Solution #31: Enabling Flexible RAs with Slice Service Area p. 108
6.31.1 Introduction p. 108
6.31.2 Functional Description p. 108
6.31.3 Procedures p. 108
6.31.3.1 Option A - Reject Slices that are Not Available in the current TA p. 108
6.31.3.2 Option B - Neither Reject nor Allow Slices that are Not Available in the current TA p. 109
6.31.4 Impacts on services, entities and interfaces p. 109
6.32 Solution #32: Solution for Network Control for UE Slice Use p. 110
6.32.1 Description p. 110
6.32.2 Procedures p. 111
6.32.2.1 PDU session Transfer from Source Slice to Target Slice, UE Initiated approach p. 111
6.32.2.2 PDU Session Transfer from Source Slice to Target Slice - Network Initiated Approach p. 112
6.32.2.3 SSC Mode and PDU Session Transfer from Source Network Slice to Target Network Slice p. 114
6.32.3 Impacts on Existing Nodes and Functionality p. 114
6.33 Solution #33: Slice-specific implicit deactivation timers p. 114
6.33.1 Functional Description p. 114
6.33.1.1 Registration control p. 114
6.33.1.2 PDU session control p. 115
6.33.2 Procedures p. 115
6.33.3 Impacts on Existing Nodes and Functionality p. 115
6.34 Solution #34: On-demand slices p. 115
6.34.1 Functional Description p. 115
6.34.2 Procedures p. 116
6.34.3 Impacts on Existing Nodes and Functionality p. 116
6.35 Solution #35: Network Slice usage control by the network p. 116
6.35.1 Introduction p. 116
6.35.2 Functional description p. 116
6.35.3 Procedures p. 117
6.35.4 Impacts on services, entities and interfaces p. 118
6.36 Solution #36: UE provided reason for registration to S-NSSAI p. 118
6.36.1 Introduction p. 118
6.36.2 Functional Description p. 118
6.36.3 Procedures p. 119
6.36.4 Impacts on services, entities and interfaces p. 120
6.37 Solution #37: Actual UE Activity-based Slice Admission Control p. 120
6.37.1 Introduction p. 120
6.37.2 Functional Description p. 121
6.37.3 Procedures p. 121
6.37.4 Impacts on services, entities and interfaces p. 123
6.38 Solution #38: On configuring the UE with UE behaviour policies p. 123
6.38.1 Introduction p. 123
6.38.2 Functional Description p. 123
6.38.3 Procedures p. 124
6.38.3.1 USIM default configuration. p. 124
6.38.3.2 Control plane procedures p. 125
6.38.3.2.1 UDM Option p. 125
6.38.3.2.2 NSSF/PCF Option 2 p. 127
6.38.3.3 URSP possible impact p. 129
6.38.4 Impacts on services, entities and interfaces p. 129
6.39 Solution #39: Serving PLMN steering UE to preferred slice for selection of PDU session p. 130
6.39.1 Description p. 130
6.39.2 Procedures p. 131
6.39.3 Impacts on Existing Nodes and Functionality p. 131
6.40 Solution #40: S-NSSAI change decided by PCF p. 131
6.40.1 Introduction p. 131
6.40.2 Functional Description p. 132
6.40.3 Procedures p. 132
6.40.3.1 The S-NSSAI change determination by PCF for an ongoing PDU session on non-roaming and local breakout roaming scenario p. 132
6.40.3.2 The S-NSSAI change determination by PCF for an ongoing PDU session triggered by an SMF report on home-routed roaming cases p. 134
6.40.4 Impacts on services, entities and interfaces p. 135
6.41 Solution #41: Network Slice change without service interruption p. 136
6.41.1 Introduction p. 136
6.41.2 Functional Description p. 136
6.41.3 Procedures p. 136
6.41.3.1 General p. 136
6.41.3.2 Change of network slice p. 136
6.41.4 Impacts on services, entities and interfaces p. 137
6.42 Solution #42: Network controlled change to an alternative S-NSSAI p. 138
6.42.1 Introduction p. 138
6.42.2 Functional Description p. 138
6.42.3 Procedures p. 139
6.42.4 Impacts on services, entities and interfaces p. 142
6.43 Solution #43: Allowed NSSAI Determination in Initial Registration to Support Network Slice Service Continuity p. 142
6.43.1 Introduction p. 142
6.43.2 Functional Description p. 142
6.43.3 Procedures p. 143
6.43.3.1 Secondary NSSAI Determination p. 143
6.43.3.2 PDU Session Transferred to a New Network Slice in No Mobility Scenario p. 144
6.43.3.3 PDU session transferred to a new network slice in mobility scenario p. 144
6.43.4 Impacts on services, entities and interfaces p. 145
6.44 Solution #44: Controlling UE access to the network per Network Slice on a per cell level granularity p. 145
6.44.1 Introduction p. 145
6.44.2 Functional Description p. 145
6.44.3 Procedures p. 146
6.44.3.1 General p. 146
6.44.3.2 Mobility procedures p. 147
6.44.4 Impacts on services, entities and interfaces p. 147
6.45 Solution #45: Constrained Service Area for the Network Slice p. 147
6.45.1 Introduction p. 147
6.45.2 Functional Description p. 147
6.45.3 Procedures p. 148
6.45.4 Impacts on services, entities and interfaces p. 148
6.46 Solution #46: Controlling network slice based on UE's inactive PDN connection p. 148
6.46.1 Introduction p. 148
6.46.2 Functional Description p. 148
6.46.3 Procedures p. 149
6.46.4 Impacts on services, entities and interfaces p. 149
7 Overall Evaluation p. 149
7.1 Evaluation for KI#1 p. 149
7.2 Evaluation for KI#2 p. 154
7.3 Evaluation for KI#3 p. 154
7.4 Evaluation for KI#4 p. 156
7.5 Evaluation for KI#5 p. 156
7.6 Evaluation for KI#6 p. 157
8 Conclusions p. 160
8.1 Conclusions for KI#1 p. 160
8.2 Conclusions for KI#2 p. 161
8.3 Conclusions for KI#3 p. 162
8.4 Conclusions for KI#4 p. 163
8.5 Conclusions for KI #5 p. 165
8.6 Conclusions for KI #6 p. 165
$ Change history p. 167
