B.1 General

23.2373GPPIP Multimedia Subsystem (IMS) Service ContinuityRelease 17Stage 2TS

This annex describes optional procedure that MSC server may perform to enhance SRVCC. Clauses B.2.1 and B.2.2 describes procedure to minimize the transcoding points for SRVCC. In clause B.2.1, the procedure is triggered after performing SRVCC, while in clause B.2.2; it is triggered prior to performing SRVCC. For minimizing transcoding feature, if enabled, at least one of these options shall be supported and deployed by MSC server and IMS within one network. Clause B.3 describes the procedure to enables the MSC server to reject SRVCC due to UE call state incompatibility.