TR 23.793
SA2
★
Study on Access Traffic Steering, Switch and Splitting support
in the 5G system architecture
use "3GPP‑Page" to get the Word version
for a better overview, the Table of Contents (ToC) is reproduced
for a better overview, the Table of Contents (ToC) is reproduced
V16.0.0 (Wzip)
2018/12 114 p.
WI Acronym: FS_ATSSS
Rapporteur: Miss So, Tricci ZTE Corporation
Rapporteur: Miss So, Tricci ZTE Corporation
The purpose of this document is to study how the 5G System (5GS) can be extended in order to support Access Traffic Steering, Switching and Splitting (ATSSS) between 3GPP and non-3GPP access networks.
full Table of Contents for TR 23.793 Word version: 16.0.0
1 Scope Word-p. 7
2 References
3 Definitions, symbols and abbreviations Word-p. 9
A Change history Word-p. 114
Access Traffic Steering: The procedure that selects an access network for a new data flow and transfers the traffic of this data flow over the selected access network. Access traffic steering is applicable between 3GPP and non-3GPP accesses.
Access Traffic Switching: The procedure that moves all traffic of an ongoing data flow from one access network to another access network in a way that maintains the continuity of the data flow. Access traffic switching is applicable between 3GPP and non-3GPP accesses.
Access Traffic Splitting: The procedure that splits the traffic of a data flow across multiple access networks. When traffic splitting is applied to a data flow, some traffic of the data flow is transferred via one access and some other traffic of the same data flow is transferred via another access. Access traffic splitting is applicable between 3GPP and non3GPP accesses.
Multi-Access PDU Session: A PDU session whose traffic can be sent over 3GPP access, or over non-3GPP access, or over both accesses.
4 Architectural requirements and assumptions
5 Key issues Word-p. 10
5.1 Key issue#1: Overall Architecture for traffic Steering/switching/splitting between Multiple Accesses
5.2 Key Issue#2: Steering between Multiple Accesses
5.3 Key Issue#3: Switching between Multiple Accesses Word-p. 11
5.4 Key Issue#4: Splitting Over Multiple Accesses
5.5 Key Issue#5: Multi-access PDU sessions (Un-trusted access)
5.6 Key Issue #6: Key issue on differentiation of 3GPP RATs in ATSSS rule Word-p. 12
6 Solutions
6.1 Solution 1: Proposed architecture framework for ATSSS
7 Conclusions
6.1.1 General Word-p. 14
6.1.2 Functional Description Word-p. 15
6.1.3 MA PDU and URSP Word-p. 16
6.1.4 Architecture Description Word-p. 17
6.1.5 Procedures Word-p. 19
6.2 Solution 2: Support of Multi-Access PDU Sessions Word-p. 34
6.1.5.1 Multi Access PDU Session Establishment Procedure
6.1.5.2 User Plane Configuration between UE-AT3SF and UPu-AT3SF
6.1.5.3 Access Measurement Report Procedure
6.1.5.4 Round Trip Time (RTT) Evaluation Procedure Word-p. 22
6.1.6 Control Plane Protocol Stack between UE-AT3SF and UPc-AT3SF
6.1.7 User Plane Protocol Stack options between UE-AT3SF and UPu-AT3SF Word-p. 23
6.1.5.3 Access Measurement Report Procedure
6.1.5.4 Round Trip Time (RTT) Evaluation Procedure Word-p. 22
6.1.7.1 User Plane Convergence Method based on NULL Tunneling
6.1.7.2 User Plane Convergence Method based on GRE tunneling
6.1.7.3 User Plane Convergence Method using L3 Generic Multi-Access Solutions (GMA) Word-p. 25
6.1.7.4 User Plane Convergence Method using L4 Multipath Solutions (MP-TCP, QUIC, MP-QUIC, SCTP, UDP generic) Word-p. 26
6.1.8 Impacts On Existing Entities and Interfaces
6.2.1 General
6.2.2 Establishment of Multi-Access PDU session with multiple PDU Session IDs Word-p. 35
6.2.3 Establishment of Multi-Access PDU session with a single PDU Session ID Word-p. 37
6.3 Solution 3: TFCP (Traffic Flow Control Protocol) based architecture framework for ATSSS Word-p. 50
6.2.3.1 Separate Establishment
6.2.3.2 Combined Establishment Word-p. 39
6.2.3.3 UE Requested MA-PDU Session Establishment Word-p. 41
6.2.4 NW-Requested MA-PDU Session Establishment Word-p. 44
6.2.5 Modify a Multi-Access PDU Session to single-access PDU session Word-p. 46
6.2.6 Modification of Multi-Access PDU session Word-p. 47
6.2.7 Release of a Multi-Access PDU Session Word-p. 49
6.3.1 Architecture framework Description Word-p. 51
6.4 Solution 4: Policy for Access Traffic Steering, Switching and Splitting
6.3.1.1 ATSSS Policy Control function description
6.3.1.2 ATSSS Policy Enforcement function description Word-p. 53
6.3.1.3 ATSSS function description for TFCP Word-p. 54
6.3.1.4 ATSSS path performance measurement function description Word-p. 56
6.3.2 Protocol Stacks Word-p. 58
6.3.3 PDU Session Establishment Procedure Word-p. 59
6.3.4 PDU Session Modification procedure Word-p. 62
6.3.5 ATSSS Execution Procedure Word-p. 64
6.3.6 Solution evaluation Word-p. 67
6.4.1 General
6.4.2 Content of ATSSS Policy Word-p. 69
6.4.3 Traffic Distribution based on ATSSS Policy Word-p. 71
6.5 Solution 5: Multipath TCP (MPTCP) proxy architecture
6.5.1 General
6.5.2 MPTCP proxy Word-p. 72
6.5.3 Addition of MPTCP proxy to 5GC
6.5.4 MA-PDU session establishment procedure for MPTCP traffic Word-p. 73
6.5.5 ATSSS and URSP rules for MPTCP Word-p. 76
6.6 Solution 6: Architecture framework with ATSSS rules via NAS and generic user plane Reporting Control Protocol Word-p. 79
6.6.1 Architecture framework Description
6.6.2 Functional Description
6.6.3 Procedures
6.7 Solution 7: Traffic Steering using Access Network Performance Measurements Word-p. 83
6.8 Solution 8: ATSSS rules for supporting 3GPP RAT differentiation Word-p. 88
6.9 Solution 9: Solution for the UL CL case on the Multi-access PDU sessions Word-p. 89
6.6.3 Procedures
6.6.3.1 ATSSS Policy Control (via NAS)
6.6.3.2 Measurement Configuration and Reporting Control Procedure (via User Plane) Word-p. 80
6.6.3.3 Control plane protocol stack between UE-AT3SF and UP-AT3SF Word-p. 82
6.6.4 Impacts on existing entities and interfaces
6.9.1 General
6.9.2 Architecture description
6.9.3 PDU session Establishment Procedure with additional UL CL and PDU session Anchor Word-p. 90
6.9.4 Insert UL CL and additional PDU Session Anchor after PDU Session Establishment Word-p. 92
6.10 Solution 10: ATSSS Solution using a MA-PDU Session
6.11 Solution 11: Interworking for Multi-Access PDU Session Word-p. 98
6.11.1 General
6.11.2 Functional Description
6.12 Solution 12: QoS framework for Multi-Access PDU Session
6.11.2.1 Interworking with N26 from EPC to 5GC
6.11.2.2 Interworking without N26 from EPC to 5GC Word-p. 100
6.11.2.3 Interworking with N26 from 5GS to EPS
6.11.2.4 Interworking without N26 from 5GS to EPS
6.11.3 Solution evaluation
6.12.1 General
6.12.2 AN Resource Allocation Word-p. 101
6.12.3 Management of GBR QoS Flow
6.12.4 Notification control Word-p. 102
6.13 Solution 13: PCC support for ATSSS
6.13.1 General
6.13.2 PCC rule Word-p. 103
6.13.3 Impacts on existing entities and interfaces Word-p. 106
6.14 Solution 14: N4 support for ATSSS
A Change history Word-p. 114
