IMS: A New Model for Blending

IP Multimedia Subsystem (IMS) technology, which merges the Internet with interactive telecommunications, represents the here and now for today’s packet-switched networks. Consequently, anyone working with or around these converging fields needs to possess a fundamental understanding of IMS and how this technology is poised to change the way new applications are designed and deployed.

IMS: A New Model for Blending Applications goes beyond most references in this field. Rather than offer the usual explanation of the standard itself, the authors address how IMS-based services might be deployed in an operator’s network. Leveraging the inside knowledge gained from years of working at the forefront of IMS research, the authors delineate the application layers and the applications that can be implemented using an IMS network. For those unfamiliar with IMS, they provide an overview of its key components and the signaling standards used for the implementation of an end-to-end IMS service.

Significant concepts are conveyed through real-life vignettes that describe how end users might actually use interactive IMS applications in the course of their day. This approach mimics the way an operator’s marketing organization might go about building a business case for IMS application deployment. While technical enough to meet the needs of engineers, this approach will greatly assist marketing, sales, and managerial professionals with gaining a basic understanding of IMS, as well as a sense of the numerous applications driving the field forward.

Mark Wuthnow is a part of AT&T’s architecture and planning organization and brings over 20 years of telecommunications experience to this work. He started his career at AT&T Bell Laboratories where he led the systems engineering teams responsible for the first three development releases of the ISDN Primary Rate Interface (PRI) for the 5ESS® switch. He later joined Southwestern Bell Technology Resources Inc. (now AT&T Laboratories) where he has been working in the wireless arena for over 15 years now. Mark has held various positions and has contributed to the various wireless subsidiaries of AT&T throughout their multiple mergers (including Southwestern Bell Mobile Systems, Cingular Wireless, and AT&T Mobility). In addition, he holds 12 patents and is also a senior member of IEEE.

Jerry Shih is currently part of AT&T’s architecture and planning organization. He has been in chair and vice-chair positions in international SDOs in the past, mostly related to messaging service development. He has been involved in OMA service enablers’ development since 2003 and is currently active in OMA converged IP messaging and converged address book service enablers’ development.Jerry Shih started his telecom career at AT&T Bell Laboratories (now Alcatel-Lucent Bell Laboratories) where he worked on digital PBX call processing software development. In his 20-plus years’ telecom career, he has worked for AT&T Bell Laboratories, BellSouth, Southwestern Bell Mobile System, Cingular Wireless, and AT&T Mobility in different capacities. He has been part of the major telecom evolutions, from ISDN to Intelligent Network to IMS.

Matthew Stafford began his telecommunications career in 1996 with SBC Technology Resources Inc. He worked on ATM and Quality of Service in IP networks. Matthew later moved to Cingular Wireless and then to AT&T as a result of its merger with Cingular Wireless. After working on various softswitch projects, Matthew wrote Signaling and Switching for Packet Telephony (Artech House, 2004). From 2004 to 2007, he served as vice chair of numbering for GSM North America. The numbering group’s main task was to develop ENUM recommendations. Matthew is currently a member of AT&T’s architecture and planning organization. Matthew is a member of IEEE.

Bill Rosenberg (Chapter 9 author) is a principal technical architect in AT&T’s architecture and planning organization. He has over 20 years of experience in terrestrial and satellite communications. Bill’s career began at TRW Space & Electronics (now Northrop Grumman Space Technology) where he was a systems engineer on satellite communication payloads. He later worked for Arrowsmith Technologies designing wireless communication systems for the company’s fleet management product. Bill joined Southwestern Bell Technology Resources (now AT&T Labs) and continued with SBC’s wireless division through its various incarnations, including Cingular Wireless and AT&T Mobility. Bill is supporting AT&T’s wireless business by developing new technologies and services. He currently develops new messaging, cell broadcast, and IMS services for GSM and UMTS designs, and contributes to industry standards. Bill played a key role in the development and launch of Video Share, which was AT&T Mobility’s first IMS-based service.

Components of an IMS Architecture. Introduction. The Path to IMS – Evolution of the Cellular Switching System to 3G. Standards Organizations for the IMS. IMS Control Plane. IMS Bearer Plane. IMS Application Plane. Security. User Equipment. IMS Signaling Primer. Overview of SIP. Session Description Protocol (SDP). XML. XML Configuration Access Protocol. Message Session Relay Protocol (MSRP). 14 DIAMETER. ENUM. IMS/OMA Based Enablers. Presence and Availability. Group List Management. Push-to-Talk over Cellular. Mobile Location Services. IP Messaging. Applications and Use Cases. IMS Ecosystem. Consumer Market Use Cases. Enterprise Market Use Cases. Converged Market Use Cases.