802.11a was a tremendously promising protocol -- capable of speeds up to 54 Mbps -- but without industry adoption even its strongest proponents were beginning to look elsewhere for results. 802.11a's most obvious selling point is bandwidth. While the b variant of the 802.11 protocol can have bursts of speed up to 11 Mbps, the a variant can go up to 54 Mbps. 802.11a's speed stems from its use of an improved encoding mechanism and a less crowded radio frequency spectrum (5 GHz rather than 2.4 GHz), which means less interference.

Release

In the year 1999 when the 802.11a was released it hasn't even been much use to implementors, because the existing devices weren't guaranteed for interoperability. But recently that's all started to change. In January 2003 the WiFi Alliance of Mountain View, California, issued 802.11a interoperability certifications covering a variety of vendor products. While only seven devices were certified, it's a milestone in the protocol's progress. The WiFi certification brings 802.11a one step closer to becoming a routine and deployable option for the enterprise, and not just a custom installation.

Protocol

And that's not the only good news for the 802.11a fan club. An emerging protocol needs the support of industry to survive, but it also needs to be tested out in the real world. Early adopters are an essential component of any technology's success, often paving the way for mass acceptance. And, as it turns out, 802.11a has picked up an early adopter with considerable clout, namely the West Point Academy.

Bandwidth

802.11a's radio frequency spectrum is called the 5 GHz .802.11a uses the available 300 MHz of the UNNI radio spectrum in three distinct 100 MHz bands. Figure 1 show the three UNNI bands and their allotted power, which differs from band to band.