Describes the technological solutions and standards which will enable the migration of voice and SMS services over to LTE/EPC networks Main drivers for the introduction of Long Term Evolution of UTRAN (LTE) is to provide far better end user experience for mobile broadband services. However, service providers also need to have a clear strategy of how to offer voice and messaging services for consumers and enterprises. The voice service over LTE is becoming increasingly important when the smartphone penetration is increasing rapidly. Smartphones require both good quality voice and high speed broadband data. This book provides the exhaustive view to industry-approved technologies and standards behind the Voice over LTE (VoLTE). Whether a decision maker or technology analyst, this book explains a topic of substantial global market interest. It provides a good introduction to the technology and is useful for operators who may be deploying VoLTE, product managers responsible for VoLTE products and those who work in implementation and standardization of related technologies. * Provides a comprehensive overview of industry-approved technologies and standards, providing vital information for decision makers and those working on the technology * Written by authors working at the cutting edge of mobile communications technology today, bringing a mix of standards and product background, guaranteeing in-depth practical and standards information * Covering the technical and practical elements of VoLTE, explaining the various approaches for providing voice services over LTE

The 3rd edition of this highly successful text builds on the achievement of the first two editions to provide comprehensive coverage of IMS. It continues to explore the concepts, architecture, protocols and functionalities of IMS while providing a wealth of new and updated information. It is written in a manner that allows readers to choose the level of knowledge and understanding they need to gain about the IMS.

With 35% new material, The IMS, IP Multimedia Concepts and Services, 3rd 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 3rd edition: Two new chapters on IMS multimedia telephony service and IMS Voice Call ContinuityUpdated information on Third Generation Partnership Project (3GPP) Release 7 level, including architecture, reference points and conceptsSubstantially extended coverage on IMS detailed proceduresCompletely rewritten and extended chapters on IMS services