Content for TR 23.856 Word version: 10.0.0
5 Performance Analysis of Rel-8 SRVCC solution
6 Alternatives
7 Assessment
8 Conclusion
A Reducing the call drop probability
B Impacts on nodes of eSRVCC alternatives
C Examples of ATCF/ATGW collocation - SIP based solution for eSRVCC
$ Change history
5 Performance Analysis of Rel-8 SRVCC solution p. 9
5.1 Analysis of SRVCC handover performance from EUTRAN to UTRAN/GERAN p. 9
5.2 Analysis of SRVCC handover performance from HSPA to UTRAN/GERAN p. 10
5.3 Analysis of call drop probability in SRVCC p. 10
6 Alternatives p. 11
6.1 Alternative 1 - enhancement using delay prediction p. 11
6.1.1 Sub-alternative #1 - prediction in MSC server p. 11
6.1.1.1 Architecture Reference Model p. 11
6.1.1.2 Functional Entities p. 11
6.1.1.2.1 MSC Server p. 11
6.1.1.3 Message Flows p. 11
6.1.1.4 A way using Pre-handover optimization to reduce the call drop probability p. 13
6.1.2 Sub-alternative #2 - prediction in SCC AS p. 13
6.1.2.1 Architecture Reference Model p. 13
6.1.2.2 Functional Entities p. 13
6.1.2.2.1 SCC AS p. 13
6.1.2.2.2 MSC Server p. 14
6.1.2.3 Message Flows p. 14
6.2 Alternative 2 - Serial Handover p. 16
6.3 Void
6.4 Alternative 4 - Media anchor in the serving network p. 17
6.4.1 Architecture Reference Model p. 17
6.4.2 Functional Entities p. 18
6.4.3 Message Flows p. 18
6.4.3.1a Originating sessions in PS p. 18
6.4.3.1b Termination sessions in PS p. 19
6.4.3.2 PS - CS Access Transfer p. 19
6.4.4 Deployment Alternatives p. 20
6.4.5 Selection of VATF p. 21
6.4.6 Maintaining IMS registration p. 21
6.5 Alternative 5 - Remote update optimization p. 22
6.6 Void
6.7 Void
6.8 Alternative 8 - SR-VCC Enhancement using anchoring in the home network p. 23
6.8.1 Sub-alternative #1: MRF selective media anchoring controlled directly by the SCC AS p. 23
6.8.1.1 Architecture Reference Model p. 24
6.8.1.2 Functional Entities p. 24
6.8.1.3 Message flows p. 24
6.8.2 Sub-alternative #2: Selective media anchoring controlled by a node other than the SCC AS p. 28
6.9 Alternative 9 - SR-VCC Enhancement using media detection p. 34
6.9.1 Introduction p. 34
6.9.2 Call flows p. 36
6.10 Alternatives 10 - eSRVCC with PDN bi-casting p. 37
6.10.1 Architecture Reference Model p. 37
6.10.2 Functional Requirements p. 38
6.10.2a IMS voice codec retrieval from PCC flow p. 38
6.10.3 Media plane handling p. 39
6.10.4 Signalling Message Flows p. 40
6.11 Alternative 11 - Media anchoring in the IMS-ALG p. 41
6.11.0 General p. 41
6.11.1 Architecture Reference Model p. 41
6.11.2 Functional Entities p. 41
6.11.3 Message Flows p. 41
6.12 Alternative 12 - HO enhancement by local anchoring with Indirect Forwarding (Merged alternative of alternatives 6 and 7) p. 44
6.12.1 Architecture Reference Model p. 44
6.12.2 Functional Entities p. 45
6.12.2.1 MSC Server/MGW enhanced for E-UTRAN/UTRAN (HSPA) and 3GPP UTRAN/GERAN SRVCC p. 45
6.12.2.2 PCC p. 46
6.12.2.3 MME p. 46
6.12.2.4 S-GW p. 46
6.12.3 Message Flows p. 46
6.13 Consolidated Alternative - SIP based solution for eSRVCC p. 53
6.13.1 Architecture Reference Model p. 53
6.13.2 Functional Entities p. 55
6.13.2.1 ATCF p. 55
6.13.2.1.1 General p. 55
6.13.2.1.2 ATCF anchoring p. 56
6.13.2.2 ATGW p. 56
6.13.2.3 SCC AS p. 57
6.13.2.4 HSS p. 57
6.13.3 Message Flows p. 57
6.13.3.1 Selection of the ATCF p. 57
6.13.3.2 Originating sessions in PS p. 59
6.13.3.3 Terminating sessions in PS p. 60
6.13.3.4 PS-CS Access Transfer p. 61
6.13.3.4.1 PS-CS Access Transfer - ATGW anchored during session setup and supporting MSC Server assisted mid-call feature p. 61
6.13.3.4.2 PS-CS Access Transfer - ATGW anchored during session setup and MSC Server assisted mid-call feature supported by SCC AS p. 63
6.13.3.4.3 PS-CS Access Transfer - ATCF not included during registration p. 64
6.13.3.4.4 PS-CS Access Transfer - ATGW not anchored during session setup p. 64
6.13.3.5 Failure to complete PS-CS Access Transfer p. 66
7 Assessment p. 66
8 Conclusion p. 69
A Reducing the call drop probability p. 70
A.1 Pre-handover optimization p. 70
B Impacts on nodes of eSRVCC alternatives p. 73
C Examples of ATCF/ATGW collocation - SIP based solution for eSRVCC p. 77
$ Change history p. 80
