Content for TR 23.725 Word version: 16.2.0
5 Key Issues
6 Solutions
7 Overall Evaluation
8 Conclusions
A Overview of IEEE TSN Frame Replication and Elimination for Reliability
B A summary of the IETF DetNet activity
$ Change History
5 Key Issues p. 10
5.1 Key Issue #1: Supporting high reliability by redundant transmission in user plane p. 10
5.2 Key Issue #2: Supporting low latency and low jitter during handover procedure p. 10
5.3 Key Issue #3: Enhancement of Session Continuity during UE Mobility p. 11
5.4 Key Issue #4: QoS Monitoring to Assist URLLC Service p. 11
5.5 Key Issue #5: Supporting low latency without requiring that the UE to always be in RRC_Connected Mode p. 11
5.6 Key Issue #6: Division of E2E PDB p. 12
5.6.1 Description p. 12
5.7 Key Issue #7: Automatic GBR service recovery after handover p. 12
6 Solutions p. 12
6.1 Solution #1 for Key Issue #1: Redundant user plane paths based on dual connectivity p. 12
6.1.1 Description p. 12
6.1.2 Procedures p. 16
6.1.3 Impacts on Existing Nodes and Functionality p. 18
6.1.4 Solution Evaluation p. 19
6.2 Solution #2 for Key Issue #1: Multiple UEs per device for user plane redundancy p. 20
6.2.1 Description p. 20
6.2.2 Procedures p. 23
6.2.3 Impacts on Existing Nodes and Functionality p. 24
6.2.4 Solution Evaluation p. 25
6.3 Solution #3 for Key Issue #1: Supporting redundant data transmission via single UPF and two RAN nodes p. 25
6.3.1 Description p. 25
6.3.1a User Plane Protocol Stack options p. 27
6.3.1a.1 Option 1: Enhancement of PDCP and GTP-U protocols p. 27
6.3.1a.2 Option2: HRP protocol layer p. 28
6.3.2 Procedures p. 29
6.3.2.1 Activate Redundant Transmission during PDU Session Establishment procedure p. 29
6.3.2.2 Activate Redundant Transmission during PDU Session Modification procedure p. 30
6.3.2.3 Handover procedure p. 30
6.3.3 Impacts on Existing Nodes and Functionality p. 31
6.3.4 Solution Evaluation p. 32
6.4 Solution #4 for Key Issue #1: Supporting redundant data transmission via single UPF and single RAN node p. 32
6.4.1 Description p. 32
6.4.2 Procedures p. 34
6.4.3 Impacts on Existing Nodes and Functionality p. 34
6.4.4 Solution Evaluation p. 35
6.5 Solution #5 for Key Issue #2: Duplication of user plane tunnelling during HO p. 35
6.5.1 Functional Description p. 35
6.5.2 Procedures p. 36
6.5.2.1 PDU session establishment or modification p. 36
6.5.2.2 Enhanced N2 based Handover p. 37
6.5.2.3 Enhanced Handover with Xn p. 38
6.5.3 Impact on existing entities and interfaces p. 39
6.5.4 Solution Evaluation p. 40
6.6 Solution #6 for Key Issue #3: Forwarding tunnel between source and target UL CL p. 40
6.6.1 Description p. 40
6.6.2 Procedures p. 42
6.6.3 Impacts on Existing Nodes and Functionality p. 43
6.6.4 Solution Evaluation p. 43
6.7 Solution #7 for Key Issue #1: Replication framework in 3GPP System p. 44
6.7.1 Description p. 44
6.7.2 Procedures p. 46
6.7.2.1 Downlink User Plane Transmission p. 46
6.7.2.2 Activate Redundant Transmission during PDU Session Establishment procedure p. 46
6.7.3 Impacts on Existing Nodes and Functionality p. 47
6.7.4 Solution Evaluation p. 47
6.8 Solution #8 for Key Issue #4: QoS Monitoring p. 47
6.8.1 Description p. 47
6.8.1.1 QoS Monitoring Activation p. 47
6.8.1.2 Enforce QoS Monitoring p. 48
6.8.1.2.1 Option 1: Using newly defined packet as monitoring packets p. 48
6.8.1.2.2 Option 2: Using actual service packets as monitoring packets p. 49
6.8.1.2.3 Option 3: Using newly defined packets based on time synchronization p. 50
6.8.1.2.4 Option 4: Using actual service packets based on time synchronization p. 50
6.8.1.3 QoS Monitoring Policy p. 51
6.8.2 Procedures p. 51
6.8.3 Impacts on Existing Nodes and Functionality p. 53
6.8.4 Solution Evaluation p. 54
6.9 Solution #9 for Key Issue 5, supporting low latency for initial data delivery without requiring that the UE to always be in RRC_Connected State p. 54
6.9.1 Description p. 54
6.9.2 Procedures p. 55
6.9.3 Impacts on Existing Nodes and Functionality p. 56
6.9.4 Solution Evaluation p. 56
6.10 Solution #10 for Key Issue #1: Multiple UEs per device for user plane redundancy with broadcast Network Reliability Group p. 56
6.10.1 Description p. 56
6.10.2 Procedures p. 57
6.10.3 Impacts on Existing Nodes and Functionality p. 57
6.10.4 Solution Evaluation p. 57
6.11 Solution #11 for Key Issue #3: Anchor change for Ethernet PDU Session p. 58
6.11.1 Description p. 58
6.11.2 Procedures p. 59
6.11.3 Impacts on Existing Nodes and Functionality p. 61
6.11.4 Solution Evaluation p. 62
6.12 Solution #12 for Key Issue #3: Ethernet PDU Session Anchor Relocation p. 62
6.12.1 Description p. 62
6.12.2 Procedures p. 63
6.12.3 Impacts on Existing Nodes and Functionality p. 64
6.12.4 Solution Evaluation p. 65
6.13 Solution #13 for Key Issue #3: Session continuity enhancement based on the coordination between AF and 5GC p. 65
6.13.1 General Description p. 65
6.13.2 Procedures p. 66
6.13.2.1 Procedure of Enhancing SSC mode 3 PDU Session Anchor Change with Multiple PDU Sessions p. 66
6.13.2.2 Procedure of Session Continuity Enhancement for a PDU Session with UL/CL or BP p. 67
6.13.3 Impacts on Existing Nodes and Functionality p. 68
6.13.4 Solution Evaluation p. 69
6.14 Solution #14 for Key Issue #2: Lossless handover by timing coordination with multiple UEs per device p. 69
6.14.1 Description p. 69
6.14.2 Procedures p. 70
6.14.3 Impacts on Existing Nodes and Functionality p. 70
6.14.4 Solution Evaluation p. 70
6.15 Solution #15 for Key Issue #6: Division of E2E PDB p. 71
6.15.1 Description p. 71
6.15.2 Procedures p. 71
6.15.3 Impacts on Existing Nodes and Functionality p. 72
6.15.4 Solution Evaluation p. 72
6.16 Solution #16 for Key Issue #7: Automatic GBR service recovery after handover p. 72
6.16.1 Description p. 72
6.16.2 Procedures p. 73
6.16.3 Impacts on Existing Nodes and Functionality p. 73
6.16.4 Solution Evaluation p. 74
6.17 Solution #17 for Key Issue #6: Configuration of CN PDB in NG-RAN p. 74
6.17.1 Description p. 74
6.17.2 Impacts on Existing Nodes and Functionality p. 74
6.17.3 Solution Evaluation p. 74
6.18 Solution #18 for Key Issue #6: Deterministic solution based accurate time stamping of packets in downlink p. 74
6.18.1 Description p. 74
6.18.2 Procedures p. 75
6.18.3 Impacts on Existing Nodes and Functionality p. 75
6.18.4 Solution Evaluation p. 75
6.19 Solution #19 for Key Issue #4: Using control plane procedure on Uu interface for QoS Monitoring p. 75
6.19.1 Description p. 75
6.19.1.1 QoS Monitoring p. 75
6.19.2 Procedures p. 76
6.19.3 Impacts on Existing Nodes and Functionality p. 76
6.19.4 Solution Evaluation p. 77
6.20 Solution #20 for Key Issue #7: SMF starts the pending timer for the non-accepted GBR QoS flow p. 77
6.20.1 Description p. 77
6.20.2 Procedures p. 77
6.20.3 Impacts on Existing Nodes and Functionality p. 77
6.21 Solution #21 for Key Issue #7: Extending notification control for QoS flow setup and handover p. 78
6.21.1 Description p. 78
6.21.2 Procedures p. 78
6.21.3 Impacts on Existing Nodes and Functionality p. 78
6.21.4 Solution Evaluation p. 79
6.22 Solution #22 for Key Issue #7: Automatic GBR service recovery after handover p. 79
6.22.1 Description p. 79
6.22.2 Procedures p. 79
6.22.2.1 QNC request for GBR Service Recovery during handover p. 79
6.22.2.2 QNC request for GBR Service Recovery after handover p. 81
6.22.3 Impacts on Existing Nodes and Functionality p. 81
6.22.4 Solution Evaluation p. 82
6.23 Solution #23 for Key Issue #7: Always On control for URLLC GBR QoS Flow p. 82
6.23.1 Description p. 82
6.23.2 Procedures p. 83
6.23.3 Impacts on Existing Nodes and Functionality p. 83
6.23.4 Solution Evaluation p. 83
6.24 Solution #24 for Key Issues #4 and #6: Accumulated packet delay estimation for QoS monitoring and division of PDB p. 83
6.24.0 General p. 83
6.24.2 Procedures p. 85
6.24.3 Impacts on Existing Nodes and Functionality p. 86
6.24.4 Solution Evaluation p. 87
7 Overall Evaluation p. 87
8 Conclusions p. 88
8.1 Key Issue #1: Supporting high reliability by redundant transmission in user plane p. 88
8.2 Key Issue #3: Enhancement of Session Continuity during UE Mobility p. 88
8.3 Key Issue #5: Supporting low latency without requiring that the UE to always be in RRC_Connected Mode p. 88
8.4 Key Issue #6: Division of E2E PDB p. 88
8.5 Key Issue #4: QoS Monitoring to Assist URLLC Service p. 89
8.6 Key Issue #2: Supporting low latency and low jitter during handover procedure p. 90
A Overview of IEEE TSN Frame Replication and Elimination for Reliability p. 91
B A summary of the IETF DetNet activity p. 92
$ Change History p. 93
