THE IMS: IP Multimedia Concepts and Services, 3rd Edition

Preface

Internet Protocol (IP) Multimedia Subsystem, better known as “IMS”, is based on the specification of Session Initiation Protocol (SIP) as standardized by Internet Engineering Task Force (IETF). But SIP as a protocol is only one part of it. IMS is more than just a protocol; it is an architecture for the convergence of data, speech, fixed and mobile networks and is based on a wide range of protocols, most of which have been developed by IETF. IMS combines and enhances them to allow real-time services on top of various kind of packet-switched technologies (GPRS, ADSL, WLAN, Cable, WiMAX, EPS).

This book was written to provide a detailed insight into what IMS is – i.e., its concepts, architecture, service and protocols. Its intended audience ranges from marketing managers, research engineers, development and test engineers to university students. The book is written in a manner that allows readers to choose the level of knowledge they need and the depth of understanding of IMS they desire to achieve. The book is also very well suited as a reference.

The first few chapters in Part I provide a detailed overview of the system architecture and the entities that, when combined, are necessary to provide IMS. These chapters also present the reference points (interfaces) between these entities and introduces the protocols assigned to these interfaces. This part ends with extensive description of essential IMS concepts such as registration, session establishment, policy and charging ...