WiMAX: broadband wireless revisited

Telecommunications Americas, March, 2004 by Sean Buckley

Hampered by proprietary systems, broken promises and MCI/WorldCom pulling out altogether from its nationwide MMDS (multichannel multipoint distribution system), the deployment of, broadband wireless, for all of its promise, has struggled to reach mainstream potential.

However, unlike those early proprietary, high-cost deployments, WiMAX (Worldwide Interoperability for Microwave Access) and its accompanying IEEE 802.16a and emerging 802.16e standards have given new life to a faltering market. Hoping to leverage similar success found with the 802.11 standards efforts, the WiMAX Forum was founded by both start-up and incumbent vendors (Alvarion, Airspan, Aperto, Proxim and WiLAN) with support from silicon vendors (Intel and Fujitsu) to promote a global standard and certify interoperability of products and technologies. At nearly 70 members, the forum has begun to attract not only more start-ups, but more importantly large OEMs such as Siemens and ZTE and operators such as AT & T and Japan's PCCW.

Designed for the sub-11-GHz bands (2 GHz to 11 GHz), the 802.16a standard creates what is in effect a wireless MAN to provide connectivity to fixed, portable and nomadic devices in addition to providing connectivity and backhaul for 802.11 hot spots. Going forward, 802.16e will add limited mobility.

Although the 802.16 standard effort was a good first step, it lacked carrier involvement. So to attract operators, WiMAX developed a carrier working group headed by Dean Chang, director of product management for Aperto Networks. With a focus on business modeling and network management issues, the group will work to consolidate input from service providers.

On the outskirts of the standard effort is Nextel Communications, which is not a WiMAX member. Late last year, the operator, which is conducting separate trials with both Flarion and IP Wireless, bought the MMDS assets of MCI and Nucentrix. On the surface, skeptics could rightly argue that Nextel's move could result in a number of endless trials, similar to WorldCom's MMDS odyssey. But during a recent keynote speech at the WCA conference in San Jose, Nextel CTO Barry West said he sees broadband wireless as a fit for the business market. West argued that the expense and proprietary nature of the products available at the time was what made previous deployments unsuccessful.

For all its potential, Pyramid Research analyst John Yunker argues that vendors and operators need a cautious approach to WiMAX. Yunker foresees a two-phase rollout, with the second stage being "disruptive." In stage one, the developments will be similar to existing equipment, while the second stage will bring on the advent of 802.16e chipsets embedded into laptops.

"There is a great deal of hype on this technology right now, said Yunker. "I am bullish on it, but I have voiced a concern that WiMAX will fail early and succeed later, simply because expectations are unrealistically high at the moment. However, the truly exciting developments won't be here for two years."

--Sean Buckley, Staff Editor