WiMax's moment of truth

This will probably be the year we find out if WiMax lives up to its billing as the next big thing in wireless technology.

Worldwide Interoperability for Microwave Access, or WiMax, aims to build on Wi-Fi's popularity. Wireless hot spots employing the 802.11 Wi-Fi standard have proliferated nationwide, but each access point provides coverage to an area measured in feet. WiMax, on the other hand, can offer coverage of as much as 31 miles on a line-of-sight basis. The technology also offers greater bandwidth and supports higher-level networking protocols than Wi-Fi.

WiMax has been the subject of a fair amount of hype, but the technology has only recently begun to solidify as standards fall into place. Last month, the Institute of Electrical and Electronics Engineers ratified a mobile WiMax standard — 802.16-2005, also known as 802.16e. That specification follows the 802.16 standard for fixed wireless applications, which IEEE approved in late 2004.

The WiMax Forum, an industry group promoting the technology's adoption, has created a conformance and interoperability test for products that use the fixed 802.16 specification. The first wave of products bearing the forum's seal of approval will likely hit the market this month.

The arrival of standards and interoperable products coincides with city governments' pursuit of ambitious wireless projects. For example, Minneapolis, San Francisco and Philadelphia plan to launch municipal wireless networks to serve residents and attract businesses. WiMax could play a role in those initiatives, according to government and industry executives.

WiMax could also find a niche in emergency communications systems, with New York City among the interested parties.

"We've talked to a number of state and local groups across the country, and I think the potential is huge for WiMax," said David Ihrie, chief technology officer at Rosettex Technology and Ventures Group. The firm participates in the federal government's National Technology Alliance program. Under that program, Rosettex has worked on a WiMax prototype project in New York.

Federal agencies, including the Defense Department, have expressed interest in the technology. The first products to meet the WiMax Forum's certification requirements will use the 3.5 GHz spectrum, which in the United States is reserved for the military.

WiMax: Fixed and mobile

Under the fixed 802.16 standard, WiMax aims for metropolitan-area network coverage and high throughput. The technology provides line-of-sight coverage of as much as 31 miles, according to a WiMax Forum white paper. It can handle data rates of as much as 70 megabits/sec, but it faces performance trade-offs and other limitations.

Beyond coverage areas and bandwidth, WiMax's Media Access Control layer provides another plus, industry executives say.

"One of the real benefits of using WiMax is that it supports a lot of the higher-layer protocols," said Imran Abbas, supervisor of CDW Government's professional services team. He cited WiMax's support of the Asynchronous Transfer Mode protocol, a networking technology commonly used in government.

A configuration of the 802.16 variety of WiMax for fixed wireless deployments consists of a base station antenna, located on top of a building or other structure. The base station provides a centralized Internet connection and broadcasts a wireless signal to client devices within its range. WiMax users can also affix antennas to mobile command vehicles.

The new mobile 802.16e WiMax standard will let users break free from a single antenna and permit roaming among multiple base stations. It will support fixed and mobile wireless services.

The existence of standards, however, does not guarantee that vendors will implement them in the same fashion. With that in mind, the WiMax Forum has devised a testing procedure to certify that products conforming to the 802.16 standard are interoperable.

Although the group's initial test focused on products operating in the 3.5 GHz band, subsequent tests will include 5.8 GHz products. Those bands are the predominant frequencies for fixed wireless applications, said Jeff Orr, the forum's marketing director.

The forum now seeks to create similar conformance and interoperability tests for the mobile WiMax standard. Orr said the forum plans to complete that task by year's end. Industry executives say they expect to see those forum-certified products on the market in 2007.

Government applications

Despite the novelty of certified products, several WiMax projects are already under way. Many early adopters hail from commercial network services providers, but government entities are exploring the technology, too.

Some see WiMax as a way to provide broadband network access in sparsely populated areas. Last year, the Special Areas Board in Alberta, Canada, selected Nortel Networks to build a broadband wireless access network based on the fixed WiMax standard.

In this case, WiMax provides an alternative to stringing wires, said Darcy Ferguson, director of finance and administration at the Special Areas Board. "We are sparsely populated out there, and distances are quite large," he said. "The infrastructure we would have to put in place to hard-wire it would be way too expensive."

The 3.5 GHz WiMax network will provide services to about 80 percent of the residents in the board's jurisdiction by this fall.

In urban areas, WiMax is expected to find a role in connecting, or backhauling, Wi-Fi hot spots. WiMax can link hot spots and consolidate previously separate Internet connections into a single one.

In 2005 Minneapolis officials selected EarthLink and US Internet to compete for the city's wireless network deal. The two vendors "are both looking at WiMax or WiMax-capable infrastructure," said Bill Beck, the city's deputy chief information officer.

He said he believes the city will initially use WiMax to backhaul existing connections.

In general, customers might tap WiMax to supplement Wi-Fi networks. Dick Lee, general manager and regional vice president of Airspan Networks, said he expects to see deployments that blend WiMax and Wi-Fi in a common platform.

WiMax not only offers the capability of backhauling Wi-Fi connections but also can serve individual locations that require higher throughput, said Lee, whose company provides broadband wireless products.

WiMax might also find use as an emergency communications tool. Greg Wilburn, mobility practice leader at GTSI, said WiMax could work well in disaster situations because the technology can be rapidly deployed and doesn't rely on cables.

First responder communications is another public safety-oriented application that could benefit from WiMax. Rosettex developed a broadband wireless prototype for police and firefighters in New York City that employs a precertified version of WiMax technology.

Military applications might also call on WiMax. "We've seen a lot of interest on the DOD side," Ihrie said, adding that the Army has been considering mobile broadband technology for use in its Future Combat Systems. "The kind of capability that WiMax brings fits well in that construct."

How well the technology's pioneers fare will determine how rapidly the market grows. "Adoption and greater penetration depend on market dynamics and user experiences," said Khalid Syed, a senior associate at Booz Allen Hamilton.