It appears that there is such a thing as more than a single industry standard when it comes to fixed/mobile convergence, or FMC. Network operators looking to offer FMC services have had to decide whether to deploy UMA technology or the VCC portion of the IP multimedia subsystem. Mostly, their choices came down to timing-use UMA for convergence now, use IMS-VCC if convergence can wait.

Unlicensed mobile access and IMS-voice call continuity are both 3GPP standards, though certainly different species: the former focusing on voice convergence at the access layer and the latter part of a broader evolutionary movement to all sorts of blended services. Meanwhile, there's still another 3GPP standard-Interworking WLAN (iWLAN)-that may find a sweet spot in the timing gap between UMA and full-on IMS architectures. That standard specifically addresses authentication and security for seamless roaming of not only voice services, but also data and video, according to Jim Grams, chief technology officer for Azaire Networks, one of the main proponents of iWLAN.

"It solves a very specific problem, creating the opportunity for automated authentication and security for a converged service session," rather than forcing users to log in, Grams said. "With a new service, you don't want to make users work too hard because it really reduces the opportunity for usage."

IWLAN actually has been around for several years, and though it was developed independent of the IMS standard, it will be compatible as IMS architectures reach broader deployment. Azaire demonstrated iWLAN in a video-sharing application late last year with partner Movial at the 3GSM World Congress Asia, and Teliasonera is already using Azaire's iWLAN-enabled platform to support a commercial video-sharing application. Also, Cingular Wireless (now AT&T) has had iWLAN in its Georgia Tech networking lab since last fall.

Grams said iWLAN's support for video convergence in particular could provide mobile carriers with a new option for delivering rich, high-quality mobile TV and video services-though that may not be what the providers of new dedicated broadcast networks want to hear. Because users of video sessions could automatically, seamlessly move from a cellular network to a higher-bandwidth Wi-Fi network when they happen upon Wi-Fi coverage, mobile carriers offering FMC conceivably could begin promoting Wi-Fi as the network of choice for viewing mobile TV and video, Grams said. Though it would take users off their own networks, they might retain happier customers who watch video more often because the quality is right.

"By blending coverage, there is an opportunity and maybe not a need for the broadcast networks, which really put carriers in the position of buying bandwidth from them and then reselling it," he said.