Patent ID: 8438257
Filing Date: 2013-05-07
Classification: H04L,H04W

Abstract:
1. A method for recovery of an IP Multimedia Subsystem (IMS) upon restart of a Serving Call Session Control Function server (S-CSCF) serving a given subscriber, the method comprising: receiving at a Home Subscriber Server (HSS), which holds subscriber data for subscribers of the IMS, contact data from a first S-CSCF serving a given subscriber of the IMS; storing at the HSS the contact data for the first S-CSCF; receiving at the HSS, upon failure of the first S-CSCF, a confirmation from a second S-CSCF of being currently selected for serving the given subscriber; and providing contact information elements selectable from the contact data from the HSS towards the second S-CSCF; wherein the contact information elements include: a contact address to reach a Proxy Call Session Control Function server (P-CSCF) through which the given subscriber has accessed the IMS, and a contact address of the user equipment in use by the given subscriber.