TR 23.793 ★
Study on Access Traffic Steering, Switch and Splitting support
in the 5G system architecture

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V16.0.0 (PDF) 2018/12 114 p.

Rapporteur:: Miss So, Tricci ZTE Corporation

essential Table of Contents for TR 23.793 Word version: 16.0.0

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2 References Word‑p. 7

3 Definitions, symbols and abbreviations Word‑p. 9

4 Architectural requirements and assumptions Word‑p. 9

5 Key issues Word‑p. 10

5.1 Key issue#1: Overall Architecture for traffic Steering/switching/splitting between Multiple Accesses Word‑p. 10

5.2 Key Issue#2: Steering between Multiple Accesses Word‑p. 10

5.3 Key Issue#3: Switching between Multiple Accesses Word‑p. 11

5.4 Key Issue#4: Splitting Over Multiple Accesses Word‑p. 11

5.5 Key Issue#5: Multi-access PDU sessions (Un-trusted access) Word‑p. 11

5.6 Key Issue #6: Key issue on differentiation of 3GPP RATs in ATSSS rule Word‑p. 12

6 Solutions Word‑p. 12

6.1 Solution 1: Proposed architecture framework for ATSSS Word‑p. 12

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

6.1.5.1 Multi Access PDU Session Establishment Procedure Word‑p. 19

6.1.5.2 User Plane Configuration between UE-AT3SF and UPu-AT3SF Word‑p. 19

6.1.5.3 Access Measurement Report Procedure Word‑p. 20

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 Word‑p. 22

6.1.7 User Plane Protocol Stack options between UE-AT3SF and UPu-AT3SF Word‑p. 23

6.1.7.1 User Plane Convergence Method based on NULL Tunneling Word‑p. 23

6.1.7.2 User Plane Convergence Method based on GRE tunneling Word‑p. 24

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 Word‑p. 33

6.2 Solution 2: Support of Multi-Access PDU Sessions Word‑p. 34

6.2.1 General Word‑p. 34

6.2.2 Establishment of Multi-Access PDU session with multiple PDU Session IDs Word‑p. 35

6.2.2.1 Separate Establishment Word‑p. 35

6.2.2.2 Combined Establishment Word‑p. 35

6.2.3 Establishment of Multi-Access PDU session with a single PDU Session ID Word‑p. 37

6.2.3.1 Separate Establishment Word‑p. 37

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 Solution 3: TFCP (Traffic Flow Control Protocol) based architecture framework for ATSSS Word‑p. 50

6.3.1 Architecture framework Description Word‑p. 51

6.3.1.1 ATSSS Policy Control function description Word‑p. 51

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 Solution 4: Policy for Access Traffic Steering, Switching and Splitting Word‑p. 67

6.4.1 General Word‑p. 67

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 Word‑p. 71

6.5.1 General Word‑p. 71

6.5.2 MPTCP proxy Word‑p. 72

6.5.3 Addition of MPTCP proxy to 5GC Word‑p. 72

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

6.5.5.1 URSP rules for MPTCP Word‑p. 76

6.5.5.2 ATSSS rules for MPTCP Word‑p. 78

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 Word‑p. 79

6.6.2 Functional Description Word‑p. 79

6.6.3 Procedures Word‑p. 79

6.6.3.1 ATSSS Policy Control (via NAS) Word‑p. 79

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 Word‑p. 82

6.7 Solution 7: Traffic Steering using Access Network Performance Measurements Word‑p. 83

6.7.1 General Word‑p. 83

6.7.2 Reference Architecture Word‑p. 84

6.7.3 Procedures Word‑p. 85

6.7.3.1 Procedure with Standalone PMF Word‑p. 85

6.7.3.2 Procedure with PMF collocated with UPF Word‑p. 87

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

6.9.1 General Word‑p. 89

6.9.2 Architecture description Word‑p. 89

6.9.3 PDU session Establishment Procedure with additional UL CL and PDU session Anchor Word‑p. 90

6.9.3.1 Establishment of Multi-Access PDU session with UL CL based on the solution 3 architecture framework Word‑p. 91

6.9.4 Insert UL CL and additional PDU Session Anchor after PDU Session Establishment Word‑p. 92

6.9.4.1 Insert UL CL to both 3GPP access and Non-3GPP access Word‑p. 92

6.9.4.2 Insert UL CL to a single access Word‑p. 94

6.10 Solution 10: ATSSS Solution using a MA-PDU Session Word‑p. 94

6.11 Solution 11: Interworking for Multi-Access PDU Session Word‑p. 98

6.11.1 General Word‑p. 98

6.11.2 Functional Description Word‑p. 98

6.11.2.1 Interworking with N26 from EPC to 5GC Word‑p. 98

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 Word‑p. 100

6.11.2.4 Interworking without N26 from 5GS to EPS Word‑p. 100

6.11.3 Solution evaluation Word‑p. 100

6.12 Solution 12: QoS framework for Multi-Access PDU Session Word‑p. 100

6.12.1 General Word‑p. 100

6.12.2 AN Resource Allocation Word‑p. 101

6.12.3 Management of GBR QoS Flow Word‑p. 101

6.12.3.1 UL GBR QoS Flow Word‑p. 101

6.12.3.2 DL GBR QoS Flow Word‑p. 101

6.12.4 Notification control Word‑p. 102

6.13 Solution 13: PCC support for ATSSS Word‑p. 102

6.14 Solution 14: N4 support for ATSSS Word‑p. 106

7 Conclusions Word‑p. 108

$ Change History Word‑p. 114

TR 23.793 ★ Study on Access Traffic Steering, Switch and Splitting support in the 5G system architecture

essential Table of Contents for TR 23.793 Word version: 16.0.0

TR 23.793 ★
Study on Access Traffic Steering, Switch and Splitting support
in the 5G system architecture