There are many SRVCC procedure, for example, from E-UTRAN-> GERAN (with DTM), E-UTRAN-> GERAN (without DTM), E-UTRAN-> CDMA1X, E-UTRAN-> WCDMA, UTRAN (HSPA) -> GERAN and many other circumstances, this article describes the E-UTRAN to 23G / CDMA1X network connection
A, SRVCC ATTACH process
If the terminal supports SRVCC functionality in the terminal MS Network ATTACH REQEUST / TAU like Capability information element in a message carrying supports SRVCC, and the ability CLASSMARK2 / CLASSMARK3 reporting (if the terminal supports)
If the network MME supports SRVCC, is established in the process of S1 AP Initial Context Setup Request specified SRVCC operation possible in the context of S1
二、SRVCC TO 3GPP
2.1 SRVCC TO3GPP network architecture
2.2 SRVCC TO 3GPP flow chart (schematic)
When the terminal is in an LTE environment, does not meet the bearer VOLTE, measured according to the measurement control terminal, and transmits a measurement report MR (e.g. A2, B2 event) network, is determined by whether the E-UTRAN handover
2.3 SRVCC TO3GPP flowchart (detail)
No DTM SRVCC process
SRVCC process with the DTM
DTM and the without distinction WithDTM processes that process without DTM handover, after the handover need to suspend GPRS GPRS Suspend
2.4、 SRVCC to3GPP LOG
2013 Jul 8 11:51:08.078 [00] 0xB0C0 LTE RRC OTA Packet -- DL_DCCH / MobilityFromEUTRACommand
三、SRVCC TO 3GPP2/CDMA1X
3.1, network infrastructure
3.2, SRVCC TO3GPP2 flow chart (schematic)
与SRVCC TO 3GPP流程基本相同，上报测量报告，然后决定是否切换，不同的是，SRVCC TO 3GPP2系统中的切换信令是通过tunelling通道进行传输，
3.3、 SRVCC TO 3GPP2流程图(详细)
3.4、SRVCC to 3GPP2LOG
目前未遇到相关测试，无LOG
