Patent ID: 7535915
Filing Date: 2009-05-19
Classification: H04L

Abstract:
1. For use in a telecommunication network, an Internet Protocol (IP) multimedia subsystem comprising: an IP switch capable of receiving Session Initiation Protocol (SIP) messages from an external IP network; and a plurality of call application nodes capable of executing a plurality of service application groups, wherein each of said service application groups comprises a primary application and a backup application associated with said primary application, wherein said IP switch distributes a first subset of said SIP messages without a group identifier to said plurality of call application nodes according to a load sharing algorithm, wherein each of a second subset of said SIP messages comprises a group identifier capable of identifying one of the service application groups, and wherein said IP switch distributes each SIP message comprising the group identifier to said plurality of call application nodes based on the group identifier, wherein if a group identifier is present the distribution of the SIP message is preformed on the basis of the group identifier, and if no group identifier is present, the distribution of the SIP message is preformed on the basis of the load sharing algorithm.