Patent ID: 8819281

Claim:
A method of forwarding a message, in a Session Initiation Protocol (SIP) based communications network and to a first SIP User Equipment associated with a SIP User Agent corresponding to a subscriber, via a controller server comprising a Serving Call Session Control Function entity and one of a plurality of traffic handler servers comprising Serving Call Session Control Function entities, and forwarding the message to a second SIP User Equipment associated with the SIP User Agent corresponding to the subscriber, via the controller server and one of the plurality of traffic handler servers, the first SIP User Equipment having first capabilities and the second SIP User Equipment having second capabilities different from the first capabilities, the method comprising: receiving, by the controller server, the message, the controller server configured to handle SIP registrations and maintain subscriber data; determining which first traffic handler server of the plurality of traffic handler servers is configured to provide a first service associated with the first capabilities, and determining which second traffic handler server of the plurality of traffic handler servers is configured to provide a second service associated with the second capabilities, each traffic handler server configured to handle at least one of SIP sessions and third party registrations; and forwarding the message from the controller server to the first SIP User Equipment via the first traffic handler server, and forwarding the message to the second SIP User Equipment via the second traffic handler server.