After the third IMS Forum Plugfest brought together 16 companies to test interoperable VoIP, video sharing and other integrated communications, industry leaders were quick to paint the event as a major milestone in proving IMS as a deployment-ready framework.
"Open IMS is no longer a question of if, but rather, how long do you really want to wait," Michael Khalilian, IMS Forum president and chairman, said in a statement. IMS (IP Multimedia Subsystem) is a framework designed to deliver seamless Internet to mobile and other devices and has been widely touted as a technology that will help make communications convergence a reality.
Despite the Plugfest's successes, however, some analysts remain skeptical of IMS's maturity.
Brian Partridge, program manager at Yankee Group, said the absence from the IMS Forum of major vendors Alcatel-Lucent, Ericsson and Nokia Siemens is problematic.
"It's difficult to say that you've got all the interoperability issues taken care of if those larger vendors aren't there," he said.
Many of those that did participate found the week-long testing deployment a positive experience.
At this Plugfest, the major focus was on testing real-world interoperability and secure delivery of services such as voice and video. Previous Plugfests, held in January and June of this year, focused on basic IP voice and routing, and on basic service interoperability, respectively.
Thomas Maufer, director of technical marketing at MuSecurity, said the events helped amplify interest in IMS. He said providers are increasingly looking into and buying MuSecurity's product, which helps test IMS networks.
"We're trying to really be organized in finding where these issues are and fixing them before they deploy," he said.
Ronald Gruia, principal analyst with Frost and Sullivan, said that the shift to IMS is ongoing, often integrating on a piece-by-piece basis.
"The reality is that the migration to IMS is happening, but it is happening at a more transitionary, gradual pace," he said. "If you are a wireless service provider, what you are going to do is not go full-blown IMS from the start."
Instead, Gruia said, service providers may first upgrade their signaling processes and then possibly soft-switch processes, while also deploying a scheme to aid service mediation.
He said that despite this approach, the shift to IMS has definitely begun, noting that French telecom Orange, ChinaMobile and Vodaphone had all either announced or sought proposals for development of their own IMS networks.
"You're going to have some forward-thinking carriers like Vodaphone who are going to think about IMS strategically instead of tactically," said Gruia. "We expect to see movement next year."
At the end of the Plugfest, the IMS Forum created an IMS "report card" to dispel what it has perceived as the myths holding back adoption. One of those myths was a response to a Yankee Group report which stated that many vendors' solutions were neither fully standards-compliant nor interoperable.
The report card stated: "Companies seen at the Plugfest are already delivering fully interoperable solutions using existing standards."
"We stand by that work," responded Partridge. "They're not in a position to dispel those myths based on getting 12 vendors together working in a lab based on their specifications." He said the reality was that many vendors were running into challenges while trying to make their products standards-compliant.
Partridge said that, despite these reservations about readiness, the move will be inevitable because providers must upgrade their legacy networks, and there are no real alternatives to IMS.
"The next generation of most products is IMS compliant," he said. "Whether you like it or not, you [will] be going with IMS, but the path is going to be very drawn out if that's the only compelling reason to go."
He said that a greater focus should be placed on the application layer to help make a more robust business case for a switch, while it is also critical to make sure the standard is one that all major participants buy into.
"How IMS can fail is it kind of folds under its own complexity," Partridge said. He warned against vendors creating their own "flavors" of IMS, such as AIMS, which Verizon proposed as an extension to the core. These moves, he said, undermined the core tenet of interoperability that was needed to make IMS succeed.
"To reinvent IMS to specifically meet the requirement of an individual operator doesn't do much good for the industry," he said.
Gruia said IMS had a lot of segments ready and more that would take time to finalize.
"I think, in general, history shows that standardization efforts take a lot of time," he said, "and by the time you finally ratify something, you come up with something that is not necessarily the most up-to-date thing."