Content for TR 23.742 Word version: 16.0.0
5 Key Issues
6 Solutions
7 Evaluation
8 Conclusions
A 3GPP SBA and ETSI NFV concepts
B Example of System Features
C Communication options for consumer-producer communication in Rel-16
$ Change History
5 Key Issues p. 11
5.1 Key Issue 1: Optimal modularization of the system p. 11
5.1.1 Description p. 11
5.2 Key Issue 2: User Plane Aspects p. 12
5.2.1 Description p. 12
5.3 Key Issue 3: Improvements to service framework related aspects p. 12
5.3.1 Description p. 12
5.4 Key Issue 4: Architectural support for highly reliable deployments p. 13
5.4.1 Description p. 13
5.5 Key Issue 5: SBA backward and forward compatibility p. 13
5.5.1 Description p. 13
5.6 Key Issue 6: System flexibility and service provisioning p. 13
5.6.1 Definition p. 13
5.6.2 Description p. 14
5.7 Key Issue 7: Roaming p. 14
5.7.1 Description p. 14
6 Solutions p. 14
6.1 Solution 1: Simply replace N4 with service operations p. 14
6.1.1 Introduction p. 14
6.1.2 High-level Description p. 14
6.1.2.1 General aspects p. 14
6.1.2.2 Bootstrap procedures p. 15
6.1.2.3 UPF Service p. 15
6.1.2.4 SMF Service p. 15
6.1.2.5 Co-existing of UPF using PtP interface and UPF using service based interface p. 16
6.1.3 Illustrated Procedures p. 16
6.1.3.1 SMF Pause of Charging procedure p. 16
6.1.3.2 Node Level Procedures between SMF and UPF p. 17
6.1.3.3 Session Level Procedures between SMF and UPF p. 18
6.1.4 Impacts on existing NFs, NF services and interfaces p. 19
6.1.5 Evaluation p. 20
6.2 Solution 2: Amendments to NF Service Interaction model p. 20
6.2.1 Introduction p. 20
6.2.2 High-level Description p. 20
6.2.2.1 Reduction of NFservice complexity p. 20
6.2.2.2 Reliability improvements p. 21
6.2.2.3 Solution Preconditions, Assumptions and Requirements p. 21
6.2.2.4 High-level Solution's Architecture p. 21
6.2.2.4.1 SAPo (Service Access Points) and SAPA (Service Access Point API) p. 22
6.2.2.4.2 Registration- Discovery and Authorization Management p. 23
6.2.2.4.3 Communication Mechanism p. 23
6.2.2.4.4 Policy Enforcement p. 23
6.2.2.4.5 Load Balancing p. 24
6.2.2.4.6 Failover Management p. 24
6.2.2.4.7 Roaming architecture p. 24
6.2.2.4.8 SAPo Implementation and Deployment options p. 25
6.2.3 Illustrated Procedures p. 26
6.2.3.1 Registration and de-registration of NF instances/NF service instances p. 26
6.2.3.2 Delivery of messages p. 27
6.2.3.3 Failover Handling Procedures p. 29
6.2.4 Impacts on existing NFs/NF services and interfaces p. 29
6.2.5 Evaluation of the Solution p. 31
6.3 Solution 3: Distributed Service Framework p. 31
6.3.1 Introduction p. 31
6.3.2 High level description p. 31
6.3.3 Services and illustrated Procedures p. 33
6.3.4 Impacts on existing Services and Interfaces p. 34
6.3.5 Evaluation of the Solution p. 34
6.4 Solution 4: Distributed 3GPP Aware Service Framework p. 34
6.4.1 Introduction p. 35
6.4.2 High level description p. 35
6.4.3 Services and illustrated Procedures p. 40
6.4.3.1 Service Registration/Update/Deregistration p. 40
6.4.3.2 Service Discovery p. 41
6.4.3.3 Service Request/Response p. 41
6.4.4 Impacts on existing Services and Interfaces p. 41
6.4.5 Evaluation of the Solution p. 42
6.5 Solution 5: Flexible Service Framework Deployment p. 42
6.5.1 Introduction p. 42
6.5.2 High level description p. 42
6.5.3 Services and illustrated Procedures p. 44
6.5.3.1 Registration and de-registration of NF instances/NF service instances p. 44
6.5.3.2 Discovery and selection of NF services and communication between consumer and producer without Centralised Service Framework p. 44
6.5.3.3 Discovery and selection of services and communication between consumer and producer with Centralised Service Framework p. 46
6.5.3.3.1 Example when 3GPP specific parameters are needed in the selection p. 46
6.5.3.3.2 Example when 3GPP specific parameters are not needed in the selection (and discovery) p. 46
6.5.3.3.3 Examples of roaming p. 48
6.5.3.4 Non-standardized services p. 48
6.5.4 Impacts on existing NF/NF Services and Interfaces p. 49
6.5.5 Evaluation of the Solution p. 49
6.6 Solution 6: Services Framework enhanced with a Service Agent p. 49
6.6.1 Introduction p. 49
6.6.2 High-level Description p. 49
6.6.3 Illustrated Procedures p. 51
6.6.4 Impacts on existing NFs, NF services and interfaces p. 54
6.6.5 Evaluation p. 54
6.7 Solution 7: SBA with stateless and unsticky services p. 55
6.7.1 Introduction p. 55
6.7.2 High level description p. 55
6.7.2.1 Solution aspects p. 55
6.7.2.2 Issues related to long-living bindings between NFs / NF services p. 55
6.7.2.3 Issues related to stateful NFs p. 56
6.7.2.4 Solution Preconditions, Assumptions and Requirements p. 57
6.7.2.5 High-level Solution Architecture p. 57
6.7.3 Services and illustrated Procedures p. 59
6.7.4 Impacts on existing Services and Interfaces p. 60
6.7.5 Evaluation of the Solution p. 60
6.8 Solution 8: Support for highly reliable deployments p. 60
6.8.1 Introduction p. 60
6.8.2 High-level Description p. 60
6.8.3 Services and Illustrated Procedures p. 60
6.8.4 Impacts on existing services and interfaces p. 63
6.8.5 Evaluation p. 63
6.9 Solution 9: Temporary bindings between the service instances p. 63
6.9.1 Introduction p. 63
6.9.2 High-level Description p. 64
6.9.3 Illustrated Procedures p. 67
6.9.4 Impacts on existing NFs, NF services and interfaces p. 68
6.9.5 Evaluation p. 68
6.10 Solution 10: NF/NF services Reliability p. 68
6.10.1 Introduction p. 68
6.10.2 High-level Description p. 69
6.10.3 Illustrated Procedures p. 70
6.10.4 Impacts on existing NFs, NF services and interfaces p. 70
6.10.5 Evaluation p. 70
6.11 Solution 11: 5GC Reliability p. 70
6.11.1 Introduction p. 70
6.11.2 High-level Description p. 70
6.11.3 Illustrated Procedures p. 72
6.11.4 Impacts on existing NFs, NF services and interfaces p. 72
6.11.5 Evaluation p. 72
6.12 Solution 12: Common Network Data Service p. 72
6.12.1 Introduction p. 72
6.12.2 High-level Description p. 73
6.12.3 Illustrated Procedures p. 73
6.12.4 Impacts on existing NFs, NF services and interfaces p. 73
6.12.5 Evaluation p. 73
6.13 Solution 13: Utilize System Feature to enable system flexibility and service provisioning p. 73
6.13.1 Introduction p. 73
6.13.2 High-level Description p. 74
6.13.3 Illustrated Procedures p. 74
6.13.4 Impacts on existing NFs, NF services and interfaces p. 74
6.13.5 Evaluation p. 74
6.14 Solution 14: NF/ Service Set based Service Framework p. 75
6.14.1 Introduction p. 75
6.14.2 High level description p. 75
6.14.3 Illustrated procedures p. 76
6.14.4 Impacts on existing NFs, NF Services and Interfaces p. 77
6.14.5 Evaluation of the Solution p. 77
6.15 Solution 15: High reliable deployment via the binding information stored at Framework Function p. 78
6.15.1 Introduction p. 78
6.15.2 High level description p. 78
6.15.3 Illustrated procedures p. 79
6.15.4 Impacts on existing NFs, NF Services and Interfaces p. 81
6.15.5 Evaluation of the Solution p. 81
6.16 Solution 16: the optimization for profile of NF/NF service instance p. 81
6.16.1 Introduction p. 81
6.16.2 High-level Description p. 82
6.16.3 Illustrated Procedures p. 82
6.16.4 Impacts on existing NFs, NF services and interfaces p. 82
6.16.5 Evaluation p. 83
6.17 Solution 17: Modularization based on NF Services only p. 83
6.17.1 Introduction p. 83
6.17.2 High level description p. 83
6.17.2.1 Principles to be used for optimal modularization p. 83
6.17.2.2 Solution Preconditions and Requirements p. 84
6.17.2.3 High-level Solution Architecture p. 84
6.17.3 Modularized 3GPP System Architecture p. 86
6.17.4 Impacts on existing NF/NF Services and Interfaces p. 86
6.17.5 Evaluation of the Solution p. 86
6.18 Solution 18: Further AMF modularization p. 87
6.18.1 Introduction p. 87
6.18.2 High-level Description p. 87
6.18.3 Illustrated Procedures p. 88
6.18.3.1 AMF or N2 Service Registration/Update/Deregistration p. 88
6.18.3.2 NG-RAN setup or configuration update p. 89
6.18.3.3 Mobile Origination procedure p. 89
6.18.3.4 Mobile termination procedure p. 90
6.18.4 Impacts on existing NFs, NF services and interfaces p. 90
6.18.5 Evaluation p. 91
6.19 Solution 19: UPF Services introduced in 5G eSBA p. 91
6.19.1 Introduction p. 91
6.19.2 High-level Description p. 92
6.19.3 Services and illustrated Procedures p. 92
6.19.4 Co-existing of N4 PtP and N4 SBI p. 92
6.19.5 Impacts on existing Services and Interfaces p. 93
6.19.6 Evaluation of the Solution p. 93
6.20 Solution 20: Service Framework based on CAPIF p. 93
6.20.1 Introduction p. 93
6.20.2 High level description p. 93
6.20.3 Backwards compatibility with Rel-15 p. 96
6.20.4 Support for roaming p. 99
6.20.5 Services and illustrated procedures p. 100
6.20.5.1 Registration p. 101
6.20.5.2 Discovery p. 101
6.20.6 Impacts on existing Services and Interfaces p. 102
6.20.7 Evaluation of the Solution p. 102
6.21 Solution 21: Hierarchical service framework p. 102
6.21.1 Introduction p. 102
6.21.2 High level description p. 102
6.21.4 Impacts on existing NF/NF Services and Interfaces p. 103
6.21.5 Evaluation of the Solution p. 104
6.22 Solution 22: Services Framework enhancement p. 104
6.22.1 Introduction p. 104
6.22.2 High-level Description p. 104
6.22.3 Illustrated Procedures p. 106
6.22.3.1 Registration and de-registration of service instances p. 106
6.22.3.2 Discovery of service instances and communication between consumer and producer service instances p. 106
6.22.4 Impacts on existing NFs, NF services and interfaces p. 108
6.22.5 Evaluation p. 108
6.23 Solution 23: Single UPF service p. 109
6.23.1 Introduction p. 109
6.23.2 High-level description p. 109
6.23.3 Service and illustrated Procedures p. 109
6.23.3.1 UPF service description p. 109
6.23.3.2 Procedures p. 110
6.23.4 Impacts on existing NFs, NF services and interfaces p. 110
6.23.5 Evaluation p. 110
6.24 Solution 24: 5GC Reliability - Resolution for Race condition p. 111
6.24.1 Introduction p. 111
6.24.2 High-level Description p. 111
6.24.3 Illustrated Procedures p. 112
6.24.4 Impacts on existing NFs, NF services and interfaces p. 112
6.24.5 Evaluation p. 112
6.25 Solution 25: Service Group for reliability and flexible deploymemt p. 112
7 Evaluation p. 117
7.1 Design Principles and Criteria for Backward Compatibility p. 117
7.2 Evaluation of the solutions for Key Issue 4 p. 118
8 Conclusions p. 118
8.1 Conclusions for KI #1 Optimal Modularization of Services p. 118
8.2 Void
8.3 Conclusions for KI #3 Improvements to service framework related aspects p. 118
8.3.1 Principles related to registration and discovery of services p. 118
8.3.2 Principles related to routing of service requests p. 119
8.3.3 Principles related to Service Framework functionality and communication between services p. 119
8.3.4 Principles related to service producers p. 119
8.3.5 Principles related to service consumers p. 119
8.3.6 Conclusions for the inter service communication in the service framework p. 120
8.4 Conclusions for KI #4 Architectural support for highly reliable deployments p. 120
8.4.1 Principles for Service Context Transfer p. 120
8.4.2 Principles for NF/NF Service/Service instance Sets p. 120
8.4.3 Conclusions on binding between consumer and producer p. 121
8.5 Conclusions for KI #5 SBA Backward and Forward Compatibility p. 122
8.6 Conclusions for KI #6 System flexibility and service provisioning p. 122
8.7 Conclusions for KI #7 Roaming p. 122
A 3GPP SBA and ETSI NFV concepts p. 123
A.1 Introduction p. 123
A.2 Architecture perspectives p. 123
A.2.1 3GPP Rel-15 architecture p. 123
A.2.2 ETSI NFV including MANO p. 123
A.3 The relationships p. 125
A.3.1 3GPP Network Function vs ETSI VNF p. 125
A.3.2 Microservice implementations and 3GPP Rel-15 SBA and ETSI NFV p. 126
A.4 Lifecycle management p. 126
B Example of System Features p. 127
C Communication options for consumer-producer communication in Rel-16 p. 128
C.1 General p. 128
C.2 Communication to resources created via SBI p. 128
C.3 Communication to resource not created via SBI p. 129
C.4 Security considerations p. 130
C.5 Roaming considerations p. 130
$ Change History p. 131
