WiMax Forum looks toward roaming

The WiMax Forum kicked off an initiative on Thursday that someday may be critical for making WiMax a true rival to cellular networks.

The industry group launched its Global Roaming Program, aimed at helping mobile WiMax operators set up roaming so subscribers can get online when they travel to areas served by other carriers. The program offers resources for service providers, including technical specifications, a manual, a contract template, and a test plan, on the organization's Web site.

[ Get the latest on mobile developments with InfoWorld's Mobile Report newsletter. ]

Domestic and international roaming is widely available among cellular operators, especially those using the most widely adopted mobile standard, GSM (Global System for Mobile Communications). WiMax is just beginning to be rolled out in many parts of the world and has a long way to go before it's as widespread as 2G (second-generation) and 3G (third-generation) mobile networks. But the WiMax Forum is smart to get the ball rolling on roaming agreements now, said Robert Syputa, an analyst at Maravedis.

"Generally, it's always favorable to have these operators do roaming, because that enhances the value of their network," Syputa said.

The program provides a "how-to" manual, a template for writing a contract between operators, a test plan for trying out roaming services with other operators ahead of launch, and specifications for exchanging information to track usage and settle the bill. The documents were developed by WiMax operators and other participants, including iPass and Verisign.

The WiMax Forum's work may help carriers get through some of the rough patches that come with setting up roaming with a new technology. But other challenges remain, according to Syputa. Carriers in different countries use different radio bands for their WiMax networks, such as 2.5GHz and 3.5GHz, and client devices may be equipped to use only one of them. In addition, service providers can allocate varying amounts of bandwidth to individual subscribers. So customers of one WiMax carrier may get a fat pipe of 1Mb per second or more at home and then find they can't use a roaming partner's network for the rich applications they're used to, he said.

In any case, it is too early for the largest U.S. WiMax operator, Clearwire, to get involved in any international roaming deals, Syputa said. With mobile WiMax commercially available in just two metropolitan areas -- Baltimore and Portland, Oregon -- Clearwire probably doesn't have enough demand to make it worthwhile.

"They need to have some critical mass" with 20 cities or more, Syputa said. That isn't likely to happen until some time in 2010, he said.