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http://www.ispworld.com/isp/newsletter/tech/standards_120701.htm 802.11 Alphabet Soup --What's "g" Got that "b" and "a" Don't? By Doug Mohney ISPworld News Are you confused over the three (3) different wireless standards, 802.11a, 802.11b, and 802.11g? Of course, each of these standards were implemented in different orders, so here's our snapshot of the three unlicensed. 802.11a - This standard uses the 5 Ghz wireless band, but different parts of the 5 Ghz band are approved for use in North American verses the rest of the world. 802.11a is designed to crank data at rates starting at 54 Mbps using an encoding scheme called orthogonal frequency division multiplexing (OFDM). Some of the hardware is incorporating proprietary schemes to use two virtual data channels for speeds of 108 Mbps. Equipment using 802.11a is just starting to hit the shelves at a list price of around $450 for a notebook PC card or $700 for an external "access point." The newly minted trade name for the standard is WiFi-5. 802.11b - Using the 2.4 Ghz wireless scheme, 802.11b is a worldwide standard that delivers throughputs of up to 11 Mbps. There are literally hundreds of thousands of cards and devices using the standard worldwide at pricing as low as $99 for a PC card and under $150 for an access point. The trade name to cover up geek label 802.11b is WiFi. 802.11g - Just ratified in November, 802.11g works in the 2.4 Ghz wireless band and is designed to support speeds at 1.1 Mbps, 5.5 Mbps, 11 Mbps, 22 Mbps, and 54 Mbps. The standard is designed to be backwards compatible with the 802.11b standard, but there may be a split of how data rates beyond 11 Mbps are implemented, since the two major wireless chip manufactures are split on how to do it. TI has a subtle lead in this race since they managed to incorporate the 22 Mbps data rate into shipping chip sets AND got their 22 Mbps standard incorporated into the 802.11g rate. No trade name has been assigned for the higher standard. Which standard is the best? From a pure technical standpoint, 802.11a is the best because it delivers the most sheer speed and is in the 5 Ghz band. The 5 Ghz band is relatively uncluttered with other devices, but 2.4 Ghz is full of extraneous garbage from wireless phones, microwave ovens, and even Bluetooth devices. (Bluetooth is a separate wireless standard designed to network PC devices) On the other hand, 802.11b is established and cheap and has an upward growth path to the faster 802.11g standard. What's New Microsoft Resource Center Live on ISPworld! If you're a Service Provider, you need to check out the Microsoft Resource Center on ISPworld. This new resource provides you with the software, support, and resources necessary to run your business more efficiently. Take advantage of technical and business resources, white papers, How-to Articles, the Microsoft Knowledge Base, licensing and certification programs, bulletin boards and much more! Just click on the Microsoft Resource Center link on the ISPworld home page! http://www.ispworld.com/msrc.htm ------------------------------------------------------------------------ -------- ISPworld Enhanced Sections More news and information can be found on ISPworld in recently launched sections: Breaking Ne