From Softswitching To IMS
Are We There Yet?

by Bob Bellman
Published April 2006; Posted August 2006


By now, you’ve probably heard about IMS, the IP Multimedia Subsystem that is designed to replace the "smokestack" architecture of traditional service provider networks. IMS decouples application services from network control and network control from network transport.


In theory at least, the IMS architecture will make it easier to develop new services and will allow any service, regardless of media type, to work across any type of network, be it fixed or mobile, IP or TDM. Proponents of IMS also promise a flood of new multimedia services that will make subscribers more productive, make mobile carriers more competitive, and rescue wireline providers from the slow death of commodity bit hauling.


As its name implies, IMS relies on standard IP-family protocols: SIP for signaling, Diameter for authentication, IPSec for encryption and so on. But carriers worldwide have already installed equipment to support their VOIP offerings, including thousands of IP softswitches, media gateways, session border controllers and application servers. Now what? Will they be able to reuse this VOIP gear in IMS, or must they scrap it and start over? Are their equipment suppliers building IMS solutions from scratch or enhancing existing technology? And will the move to IMS create opportunities for new equipment vendors, or have incumbents already locked up the market?



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About the author:

Bob Bellman has more than 35 years of engineering, sales and marketing experience in the computer and communications industry. As an independent consultant since 1994, he has provided marketing and writing assistance to dozens of successful equipment vendors and service providers.


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