With 35% new material, The IMS,IP Multimedia Concepts and Services, 3^rd Edition has been completely revised to include updated chapters as well as totally new chapters on IMS multimedia telephony and IMS voice call continuity. Additional new material includes IMS transit, IMS local numbering, emergency sessions, identification of communication services in IMS, new authentication model for fixed access, NAT traversal and globally routable user agents URI. Detailed descriptions of protocol behaviour are provided on a level that can be used for implementation and testing.

Key features of the 3^rd edition:

• Two new chapters on IMS multimedia telephony service and IMS Voice Call Continuity
• Updated information on Third Generation Partnership Project (3GPP) Release 7 level, including architecture, reference points and concepts
• Substantially extended coverage on IMS detailed procedures
• Completely rewritten and extended chapters on IMS services