摘要 |
An IP Multimedia Subsystem (IMS) architecture for IP multimedia services is provided with a given user equipment (UE); a gateway support node (GGSN) configured to handle packet transmission to/from the given UE; and a proxy call session control function (P-CSCF) configured to serve as a first contact point of the UE and provide session management services, including establishing a packet data protocol (PDP) context for IMS related signaling, registration, and other procedures for IMS sessions. The P-CSCF is also configured to perform the following: storing identification information from the given UE during registration in memory; receiving a SIP (Session Initiation Protocol) message from the given UE; comparing identity in the SIP message with the identification information stored with a link to a Policy Decision Function (PDF); and using the same PDF for all operations of the given UE, when the identity in the SIP messages matches the identification information stored in memory. |