A Proposal of Live Session Migration for Call Session Control in IMS

摘要

This paper proposes a design achieving IMS session migration which allows the IMS to distribute sessions for minimizing servers and/or restoring sessions admitted by the halted a call session control function (CSCF) server, that is a SIP server. The session migration gains the flexibility in operation and minimizing CSCF servers by a granular session distributions. Our design maps an SIP URI (a kind of a phone number in the telephone service case) to a flow routed by the Openflow switches. Our mapping approach can avoid excessive increase of the flow entries, but requires extracting the SIP URI from a SIP message at the gateway which is one of the introduced functions. Evaluation shows that the introduced functions merely affect the SIP signaling call flows, such as for initiating and terminating services.