Mobile network having IP multimedia subsystem (IMS) entities and solutions for providing simplification of operations and compatibility between different IMS entities

An IP Multimedia Subsystem (IMS) architecture for IP multimedia services, comprising:

• 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,
• wherein said P-CSCF is further 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.

A process of providing Proxy Call State Control Function (P-CSCF) in a mobile network, comprising:

• storing identification information from a given user equipment (UE) at registration in memory;
• receiving a SIP (Signal Initiated 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.

A computer readable medium comprising instructions that, when executed by a mobile network, perform a method of providing Proxy Call State Control Function (P-CSCF) in a mobile network, the method comprising:

• storing identification information from a given user equipment (UE) at registration in memory;
• receiving a SIP (Signal Initiated 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.