Methods, systems, and computer program products for clustering and communicating between internet protocol multimedia subsystem (IMS) entities

A system for implementing a plurality of Internet protocol (IP) multimedia subsystem (IMS) functions, the system comprising:

• an IMS node comprising a single hardware platform including:
• (a) a first IMS module located in the IMS node for implementing a first IMS function associated with establishing and controlling communication sessions between IMS users;
• (b) a second IMS module located in the IMS node for implementing a second IMS function, different from the first IMS function, associated with establishing and controlling communication sessions between IMS users, the second IMS module including a shared data store containing subscriber information that is directly accessible by an S-CSCF processor that implements the second IMS function;
• and
• (c) a local bus internal to the IMS node for connecting the first and second IMS modules.