Electro/Telecom Industry Trends
September 2003
IEEE’s 802.11g revs up wireless networking
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Wi-Fi wanna-be’s who have been waiting for wireless networking to speed up now have reason to rejoice. The Institute of Electrical and Electronics Engineers, Inc. (IEEE) launched its 802.11g standard last June. Combined with 802.11a, the new standard lays a solid foundation for further development of wireless LAN technology.
A brief history of the 802.11 alphabet
“802.11g’s origins are with 802.11b,” notes Brian Mathews, IEEE 802.11 working group publicity chair. “We began with 802.11 in 1997, but it had a speed limit of 2 Mbps. So we developed the 802.11a and b standards in parallel to address speed issues. 802.11b pushes 11 Mbps, while 802.11a has a maximum speed of 54 Mbps.”
Mathews notes that while 802.11a was faster, written for the less crowded 5.2 GHz frequency and generally considered more sophisticated technology, it didn’t gain more popularity than its 2.4 GHz cousin, 802.11b. “Since they’re more plentiful, components for the 2.4 GHz band tend to be cheaper than those for the 5.2 GHz band, Mathews observes. “Plus, there was a perceived power consumption disadvantage with the higher, 5.2 GHz frequency, and regulatory agencies outside the U.S. hadn’t finalized rules on that band.” All those factors combined to make the 802.11b the people’s choice for wireless LANs.
The need for speed
“A lot of people didn’t go wireless because they didn’t think it was fast enough,” says Mathews. “In the early- to mid-1990s, many companies upgraded their Ethernets to 100 Mbps, so the 11 Mbps of 802.11b devices was way too slow. And many corporate IT people were hesitant to add 802.11a technology because of the price and their concerns about compatibility.”
To woo the reluctant, 802.11g builds on past 802.11 successes while putting a salve on technical sore spots. The new standard:
- Stays within the 2.4 GHz band for lower-cost device components
- Speeds up access, with a minimum of 24 Mbps and top throughput rate of 54 Mbps
- Adapts the modulation technique used by 802.11a, orthogonal frequency division multiplexing or OFDM, to increase speeds in the 2.4 band and support 802.11b products
- Remains backward compatible with 802.11b devices so users won’t need to reinvest in basic equipment
Before the standard was approved in June, manufacturers were already engineering WLAN devices to meet its protocols. By July, the Wi-Fi Alliance was giving its nod of approval to the first batch of 802.11g products. Apple Computers took only a week to send users an update bringing AirPort Extreme base stations up to 802.11g specifications.
Three years in the making, the 802.11g standard, together with 802.11a, will likely prevail for several years as the cornerstone of Wi-Fi development. “The rapid acceptance of 802.11g is confirmation that our working groups are doing something right,” says Mathews. “We’re pleased to see how quickly 802.11 standards are embraced as the leading wireless networking technology.”