Now that the broadband wireless industry can boast some bona fide WiMAX Forum-certified products - with several more on deck for certification testing - will WiMAX services suddenly proliferate as an enterprise-class, last-mile access alternative?

Not overnight. There is still much carrier testing ahead using the certified products.

802.16-2004 WiMAX standards specify a form of "fixed" wireless broadband communication from a stationary subscriber location to a carrier's base station on a cell tower. The network's theoretical maximum throughput is about 70Mbps, shared by multiple service customers in increments divvied up by the service provider.

Product certification is a positive development for carriers seeking interoperable equipment choices, such as those who might wish to offer different vendors' CPE to different classes of commercial customers. But don't hold your breath for a flood of standards-based services. Most of the broadband wireless services in trial and commercial deployment use "pre-WiMAX" equipment that was built before the 802.16-2004 standard was ratified.

Aperto customer TowerStream, for example, has been using older Aperto gear to deploy commercial service and intends to begin trialing the certified Aperto base station and other vendors' certified equipment "as soon as possible," says Jeff Thompson, CEO. TowerStream offers fixed broadband wireless services in the U.S.'s top five cellular markets.

Meantime, AT&T conducted pre-WiMAX trials in Alaska and New Jersey throughout the second half of 2005, during which it determined that WiMAX is capable of performing on a par with T-1 technology. The gear didn't support WiMAX capabilities for encryption and QoS, so workaround approaches were used.

Meanwhile, AT&T has recently launched trials with 15 customers in Atlanta using equipment built to the 802.16-2004 standard, but not yet certified, including non-line of sight (NLOS) products. AT&T says it expects that licensed spectrum will be required for WiMAX services with service-level agreements.

"We plan to keep our options open, though, as our testing has shown that there could be potential in using a combination of unlicensed and licensed spectrum," said a company spokesperson.

AT&T has not detailed how it intends to procure licensed spectrum for commercial services. The FCC is poised to auction off 700 MHz spectrum as early as fall 2006, though early WiMAX-standard products operate in the 2.5 GHz band in the U.S., 3.5 GHz band internationally and in the 5.8 GHz unlicensed band.