Content for TR 23.700-28 Word version: 18.1.0
5 Key Issues p. 11
5.1 Key Issue #1: Mobility Management enhancement with discontinuous satellite coverage p. 11
5.2 Key Issue #2: Power saving enhancement for UE in discontinuous coverage p. 11
6 Solutions p. 12
6.0 Mapping of solutions to key issues p. 12
6.1 Solution #1: Power Saving based on AMF awareness of coverage information p. 12
6.1.1 Description p. 12
6.1.2 Procedures p. 13
6.1.3 Impacts on services, entities and interfaces p. 15
6.1.4 Solution evaluation p. 15
6.2 Solution #2: predictive Power Saving Mode p. 16
6.2.1 Description p. 16
6.2.2 Procedures p. 16
6.2.3 Impacts on services, entities and interfaces p. 17
6.2.4 Solution evaluation p. 17
6.3 Solution #3: Power Saving based on UE awareness of coverage information p. 17
6.3.1 Description p. 17
6.3.2 Procedures p. 19
6.3.3 Impacts on existing nodes and functionalities p. 20
6.3.4 Solution evaluation p. 20
6.4 Solution #4: Mobility Management enhancement based on coverage information and UE location p. 21
6.4.1 Description p. 21
6.4.2 Procedures p. 21
6.4.3 Impacts on services, entities and interfaces p. 22
6.4.4 Solution evaluation p. 22
6.5 Solution #5: Power Saving based on updating parameters before releasing signalling connection p. 23
6.5.1 Description p. 23
6.5.2 Procedures p. 23
6.5.3 Impacts on services, entities and interfaces p. 24
6.5.4 Solution evaluation p. 24
6.6 Solution #6: Discontinuous coverage architecture p. 25
6.6.1 Description p. 25
6.6.2 High level architecture principles p. 25
6.6.3 Impacts on services, entities and interfaces p. 27
6.7 Solution #7: Utilizing discontinuous coverage wait timer for satellite discontinuous coverage scenario p. 27
6.7.1 Description p. 27
6.7.2 Procedures p. 29
6.7.3 Impacts on services, entities and interfaces p. 29
6.7.4 Solution Evaluation p. 30
6.8 Solution #8: Leaving Coverage Notification p. 30
6.8.1 Description p. 30
6.8.2 Procedures p. 31
6.8.2.1 Leaving Coverage Notification Procedure in 5GS p. 31
6.8.2.2 Leaving Coverage Notification Procedure in EPS p. 32
6.8.3 Impacts on services, entities and interfaces p. 32
6.8.4 Solution evaluation p. 32
6.9 Solution #9: Modification of Timers when in or out of Coverage p. 32
6.9.1 Description p. 32
6.9.2 Procedures p. 33
6.9.3 Impacts on existing nodes and functionalities p. 34
6.9.4 Solution evaluation p. 34
6.10 Solution #10: UE Reachability Events with Expected in Coverage Time p. 34
6.10.1 Description p. 34
6.10.2 Procedures p. 35
6.10.3 Impacts on existing nodes and functionalities p. 35
6.10.4 Solution evaluation p. 35
6.11 Solution #11: Combined UE Management Architecture p. 36
6.11.1 Description p. 36
6.11.2 Procedures p. 37
6.11.2.1 5GS UE Leaving Coverage Procedure p. 37
6.11.2.2 EPS UE Leaving Coverage Procedure p. 38
6.11.2.3 EPS and 5GS UE Returning to Coverage Procedure p. 39
6.11.3 Impacts on existing nodes and functionalities p. 39
6.11.4 Solution evaluation p. 39
6.12 Solution #12: Minimize discontinuous coverage by inter-RAT handover processing p. 40
6.12.1 Description p. 40
6.12.2 Procedures p. 40
6.12.3 Impacts on existing nodes and functionalities p. 41
6.12.4 Solution evaluation p. 42
6.13 Solution #13: Applicability of no service in discontinuous coverage p. 42
6.13.1 Description p. 42
6.13.2 Procedures p. 44
6.13.2.1 Network decides UE action during discontinuous coverage period p. 44
6.13.2.2 UE decides its action during discontinuous coverage period p. 45
6.13.3 Impacts on services, entities and interfaces p. 46
6.13.4 Solution evaluation p. 46
6.14 Solution #14: Wait timer for discontinuous coverage p. 46
6.14.1 Description p. 46
6.14.2 Procedures p. 47
6.14.3 Impacts on existing nodes and functionalities p. 47
6.14.4 Solution evaluation p. 47
6.15 Solution #15: Solution to support Provision of Coverage Data to a UE p. 48
6.15.1 Description p. 48
6.15.2 Procedures p. 49
6.15.2.1 Obtaining Coverage Data using an HTTPS or SMS Query to a Server p. 49
6.15.2.2 Obtaining Coverage Data using NAS p. 50
6.15.2.3 Obtaining Coverage Data using an DCAF and NWDAF p. 51
6.15.3 Impacts on existing nodes and functionalities p. 54
6.15.3.1 Obtaining Coverage Data using an HTTPS or SMS Query to a Server p. 54
6.15.3.2 Obtaining Coverage Data using NAS p. 54
6.15.3.3 Obtaining Coverage Data using an DCAF and NWDAF p. 55
6.15.4 Solution evaluation p. 55
6.16 Solution #16: Solution to support a UE Triggered Generalized Unavailability Period p. 56
6.16.1 Description p. 56
6.16.2 Procedure for UE Triggered Generalized Unavailability Period p. 57
6.16.3 Impacts on existing nodes and functionalities p. 58
6.16.4 Solution evaluation p. 59
6.17 Solution #17: Solution with event list coverage information over NAS p. 59
6.17.1 Description p. 59
6.17.2 Procedures p. 61
6.17.2.1 Coverage information provided to UE using NAS signalling p. 61
6.17.2.2 Coverage information retrieved by AMF from CMNF p. 62
6.17.3 Impacts on existing nodes and functionalities p. 63
6.17.4 Solution evaluation p. 63
6.18 Solution #18: Response to Nnef_ParameterProvision request containing Maximum Latency p. 64
6.18.1 Description p. 64
6.18.2 Procedures p. 65
6.18.3 Impacts on services, entities and interfaces p. 66
6.19 Solution #19: AMF/MME awareness of coverage times based on AF parameter provisioning p. 66
6.19.1 Description p. 66
6.19.2 Procedures p. 67
6.19.3 Impacts on services, entities and interfaces p. 67
6.19.4 Solution evaluation p. 68
6.20 Solution 20: UE-specific Dynamic Tracking Areas p. 68
6.20.1 Description p. 68
6.20.2 Procedures p. 69
6.20.2.1 Registration/TAU based on UE-DTA p. 69
6.20.2.2 Paging triggering based on UE-DTA registration p. 71
6.20.3 Impacts on services, entities and interfaces p. 71
6.20.4 Solution evaluation p. 72
6.21 Solution #21: NWDAF assisted power saving mechanism for UE in discontinuous NTN coverage p. 73
6.21.1 Description p. 73
6.21.2 Procedures p. 74
6.21.2.1 Procedure for UE initiates negotiation of PSM/MICO/eDRX p. 74
6.21.2.2 Procedure for AMF initiated negotiation of PSM/MICO/eDRX p. 76
6.21.2.3 Procedure for NWDAF assisted NTN coverage analytics p. 78
6.21.3 Impacts on services, entities and interfaces p. 79
6.21.4 Solution Evaluation p. 79
6.22 Solution #22: Coverage data transfer in 5GS and EPS p. 80
6.22.1 Description p. 80
6.22.2 Procedures p. 82
6.22.2.1 Coverage data transfer at 5GS Registration p. 82
6.22.2.2 Coverage data transfer at 5GS PDU Session Establishment p. 84
6.22.2.3 Coverage data transfer at EPS PDN Connection Establishment p. 85
6.22.3 Impacts on existing nodes and functionalities p. 86
6.22.4 Solution evaluation p. 87
6.23 Solution #23: Handling of the UE attempt to Connected mode p. 87
7 Overall Evaluation p. 87
7.1 Rel.17 solution for support of discontinuous satellite coverage p. 87
7.2 Methodology p. 88
7.3 Requirements, Impacts and System Assumptions p. 89
7.4 Coverage Information Provisioning p. 90
7.5 KI Requirements Solution Evaluations p. 91
7.5.1 Solution Mapping to Requirements and Impacts p. 91
7.5.2 Solution Categorisation p. 92
7.5.3 Solutions for general mobility management and/or power saving p. 93
7.5.4 Signalling load on target RAT/PLMN p. 94
7.5.5 Solutions for alternative RAT/PLMN selection p. 95
7.6 Functional Evaluation p. 95
8 Conclusions p. 101
8.1 Conclusion on general mobility management and/or power saving p. 101
8.2 Conclusion on overload impacts to a target RAT/PLMN p. 102
8.3 Conclusion on alternative RAT/PLMN selection p. 102
$ Change history p. 103
