The IMS Difference

Is the IP multimedia subsystem architecture any different from any earlier, barely successful efforts at broad-based telecom infrastructure standards? The answer is that IMS has a far stronger opportunity to succeed in commercial deployments. Previous standards possessed “killer flaws” that stifled widespread adoption, namely narrow participation in standards development, a focus on technology rather than marketing, weak business cases and lack of early commercialization support from industry forums.

• Greater participation: Led by large telecom companies and their suppliers, international initiatives for ISDN, ATM and intelligent networking standards included minimal participation from computer and data networking vendors. As a result, these standards did little to support the growing set of IP-based data applications that spawned the Internet revolution.

  These three telecom standards, implemented in many service provider networks, did not dramatically affect the overall communications infrastructure technology. ATM (and to some extent, frame relay) addressed this weakness through industry forums that solicited participation from computer and data vendors. However, the overall impact of the standards was blunted because key industry segments were not fully represented in the early stages of development.

  IMS also has roots in the telecom standards bodies, but similarities with earlier efforts end there. Early in the IMS standardization process, active participation was sought from computer and data vendors. Indeed, the standards were clearly based on IP, and mechanisms were put in place to coordinate with the Internet Engineering Task Force. As a result, there is significant cross-industry participation in IMS development.

  Moreover, the diversity of vendors supporting IMS includes not only telecom infrastructure players but also software vendors and content companies. Such broad participation and the cross-fertilization of IP and mobility within IMS is probably the strongest indicator for the long-term acceptance and deployment of IMS.

• Emphasis on services, not technology: Earlier standards defined complex new protocols without providing new customer benefits or economics. IMS provides specifications for an IP-based architectural blueprint enabling creation and delivery of sophisticated multimedia communications and content services. It enables new services that are difficult to implement with a non-IP solution. Many service providers and vendors are now shifting their focus from technology trials to service planning and realization.

• Stronger business cases: Earlier telecom standards suffered from the lack of clear business cases. However, IMS builds on a number of economic benefits offered by IP technology that could translate into compelling long-term financial value. IMS offers a number of quantifiable and “soft” benefits, including avoided CAPEX achieved by offloading the radio access node network to voice-over-IP networks, better transport interconnection economics with ILECs and faster time to market.

  Soft benefits include lower long-term costs of service creation and delivery by using standards such as open service access/Parlay to integrate and standardize the applications interface. For operators with multiple network assets, these benefits could be especially significant.

• Support from industry forums: Earlier telecom standards efforts did not proactively address industry forum support for early commercialization. The ATM and frame relay industry forums were exceptions and did experience some success in developing interoperability specifications.

Multi-vendor interoperability is now recognized as one of the most challenging aspects of IMS deployment, not only for intra-network integration points but also across service provider networks. For IMS to see rapid adoption, the creation of a well-attended industry forum that irons out the kinks of multi-vendor and multi-carrier interoperability is a critical success factor.

PK Prasanna is IMS/convergence lead for inCode, a global wireless business and technology consulting firm. You can reach him at pprasanna@incodewireless.com.