Content for TR 23.894 Word version: 10.0.0
6 Scenarios and Solutions for local breakout
7 Scenarios and Solutions for optimal routeing of media
8 Evaluation of the Solutions
9 Conclusions
A OMR use cases
B Interconnect Assumptions
$ Change history
6 Scenarios and Solutions for local breakout p. 9
6.1 Scenarios p. 9
6.1.1 P-CSCF located in home network - dual IP address p. 9
6.1.2 P-CSCF located in home network - single IP address p. 10
6.1.3 P-CSCF located in serving network p. 10
6.2 Alternative 1: Dual IP address p. 11
6.2.1 Description p. 11
6.2.2 Impact on IMS p. 14
6.2.3 Impact on EPS p. 14
6.2.4 Impact on UE p. 15
6.3 Comparison of the scenarios p. 15
7 Scenarios and Solutions for optimal routeing of media p. 15
7.1 Scenarios p. 15
7.2 Alternative 1: Extension to SDP for TrGW bypass p. 16
7.2.1 Introduction p. 16
7.2.2 Reference Architecture p. 17
7.2.3 Description of base algorithm p. 18
7.2.4 Description of active bypass option p. 21
7.2.4.1 Overview of Operation of the Active-Bypass Option p. 21
7.2.4.2 Example flow for Active Bypass Option p. 22
7.2.5 Interactions with Transcoding p. 24
7.2.5.1 Transcoding with the base algorithm p. 24
7.2.5.2 Codec-aware option p. 25
7.2.5.2.1 General p. 25
7.2.5.2.2 Procedures p. 25
7.2.6 Interworking with PSTN p. 26
7.2.7 Interaction with local breakout p. 26
7.2.8 Protecting network resources p. 27
7.2.9 Network interconnect issues p. 27
7.2.10 Resource admission control p. 27
7.2.11 Lawful Intercept p. 27
7.2.12 Charging p. 28
7.2.13 Common transit scenario p. 28
7.3 Alternative 2: Transcoding aware p. 29
7.3.1 Description of the base algorithm p. 29
7.3.2 Procedures and call flows p. 30
7.3.2.1 Call flow for base algorithm p. 30
7.3.2.2 Last TrGW can be bypassed p. 31
7.3.2.3 IMS-ALG controls additional TrGW(s) p. 32
7.3.3 Handling of removed codec p. 33
7.3.4 Interactions with Transcoding p. 34
7.3.5 Enhancement of the algorithm p. 35
7.3.6 Improvement to proactive transcoding p. 37
8 Evaluation of the Solutions p. 39
8.1 Evaluation Criteria p. 39
8.2 Evaluation Results p. 39
9 Conclusions p. 40
A OMR use cases p. 42
A.1 Discussion p. 42
A.2 Common Transit Network p. 43
A.3 Common Serving Network p. 44
A.4 Two Transit Networks (1) p. 46
A.5 Two Transit Networks (2) p. 46
A.5.1 Two Transit Networks (2) - Example optimization p. 46
A.5.2 Two Transit Networks (2) - Alternative optimizations p. 47
A.6 Four transit networks p. 48
A.7 User performs SC p. 49
A.8 User splits media across access networks p. 51
A.9 Media server in Home A p. 51
A.10 No Transit networks p. 52
A.11 Optimal media routing in PSTN local breakout p. 53
B Interconnect Assumptions p. 55
B.1 Direct Interconnects p. 55
B.2 In-direct Inter-connects p. 55
B.2.1 Interconnection over "Internets" p. 55
B.2.2 Interconnections over IPX networks p. 55
B.2.2.1 General p. 55
B.2.2.2 Transport mode p. 56
B.2.2.3 Service transparent mode: p. 56
B.2.2.4 Hubbing mode p. 56
B.2.2.5 Roaming Interconnections p. 57
B.2.3 Interconnection using IMS transit functionality p. 57
B.3 Actions at Interconnects that may affect OMR p. 57
$ Change history p. 59
