Metro area broadband wireless provider TowerStream is branching out into the mobile IP telephony arena, announcing today it is leveraging its New York pre-WiMax wireless access network to launch a network of Wi-Fi hot spots geared entirely at users of new VoIP-enabled handsets.

TowerStream is deploying clusters of Wi-Fi hot spots, both in straight point-to-point backhaul configuration and in mesh topologies, in several high-traffic areas of New York City. The provider initially will be offering up the network for free as a beta trial allowing them to use the network as an extension of their Vonage or Skype accounts. TowerStream just finished an in-house trial of the technology in a limited area in its first market in Providence, R.I.--including testing successful call hand-off from access point to access point--and according to Chief Technology Officer and Co-founder Jeff Thompson, TowerStream believes the technology is ready for public consumption.

"The key to this beta is to get as much information as possible so we can learn how to scale this network as the technology evolves," Thompson said. "If it's successful in New York, we'll grow it out in the city and to our other markets."

While Wi-Fi-enabled handsets are still a rarity, they are definitely making their way into the hands of early adopters. The potential market may be small now, but Thompson said the technology is rapidly gaining momentum and TowerStream wanted to be on its leading edge. While the Beta trial will focus on individual consumers, a commercial service would target individual customers, VoIP providers like Vonage, and possibly even carriers looking to offload cellular minutes from their networks.

Thompson said TowerStream is evaluating several vendors' Wi-Fi gear for the trial. He declined to name the vendors but will be using its Aperto and Alvarion broadband wireless gear to backhaul the hot spots onto its IP backbone, bypassing the local exchange provider entirely. The cost savings of using its own access network as a backhaul would be significant and it gives the network room to grow. TowerStream claims it can scale bandwidth up to a single hot spot to 100 Mb/s symmetrically, far greater than the bandwidth provided by the T-1 and DSL lines feeding most hot spots. "We have the network, so we're leveraging that position," Thompson said. "Not many people can do that--unless you're Verizon."

TowerStream's core business is selling broadband access to medium businesses and enterprises, using multiple base stations stacked on skyscrapers to directly link them to a "wireless fiber" ring in the sky. Following the model of Teligent and Winstar except much more cautiously and with second-generation equipment, TowerStream has been deploying slowly in the major metro hubs, starting in its hometown Providence and moving to Boston, New York, Chicago and Los Angeles. Its next market launch in San Francisco will go live next quarter.

While it's currently using the proprietary gear of Aperto and Alvarion, the carrier has firmly gotten behind the WiMax standards and has committed to deploying WiMax 2004 (802.16d) gear as soon as it makes it through certification later this year. Thompson said TowerStream also plans to follow WiMax's evolution toward mobility, deploying 802.16e gear when available. When that happens, he said, any Wi-Fi network the company has built will synch easily with its wide area network technologies, allowing customers to roam seamlessly between Wi-Fi to WiMax to (with the aid of SIP-fueled IMS core) cellular. Those plans are still far off in the future though, Thompson cautioned. First TowerStream has to get customers to participate in the Wi-Fi trial.

"We may get 10; we may get 10,000," Thompson said. "Hopefully we'll get enough feedback to properly evaluate the service."