Patent ID: 8422488

Claim:
A method of registering during a single registration process in an IP Multimedia Subsystem “IMS” at least one implicit registration set selected from: an implicit registration of a number ‘n’ of IMS private identities and an implicit registration of a number ‘m’ of contact addresses, the method comprising: receiving at a Home Subscriber Server “MSS”, which holds subscriptions for subscribers of the IMS, from a Serving Call Session Control Function “S-CSCF”, which is currently assigned for serving a subscriber of the IMS, an indication of a registration of said subscriber with a given IMS public identity “IMPU” and a given IMS private identity “IMPI”, and an identifier of said S-CSCF; configuring subscriber data for the subscriber at the HSS with at least one implicit registration set selected from: a set including a number ‘n’ of IMPIs associated with the given IMPI or with the given IMPU, and a set including a number ‘m’ of contact addresses per IMPI basis; downloading from the HSS towards the S-CSCF said at least one implicit registration set; and building up a data model in the S-CSCF comprising: the given IMPI explicitly registered, the given IMPU explicitly registered, and the at least one implicit registration set selected from: the set including a number ‘n’ of IMPIs associated with the given IMPI or with the given IMPU, and the set including a number ‘m’ of contact addresses per IMPI basis.