New products based on the draft 802.11g standard are beginning to appear on retail shelves and prices lists. Vendors rushing to the "G party" include Actiontec (54 Mbps Wireless), Apple (AirPort Extreme), Buffalo (AirStation G54), D-Link (AirPlus Xtreme G), and Linksys (Wireless-G). Consumers struggling to choose between 802.11a and 802.11b now face another decision: whether and when to migrate to 802.11g.
A hybrid mode that combines B's CCK with G's OFDM
This compromise was approved last September, but the standard will not be ratified until May 2003. The Wi-Fi Alliance has already conducted private interoperability tests, but formal certification will not start until the standard is ratified.
When to migrate
G products sold today are likely to require firmware upgrades to comply with the ratified standard and resolve early interoperability glitches when operating at higher data rates. If you can't wait three to six months to dive into G, plan ahead for upgrades.
G throughput declines in a mixed-mode WLAN of B and G stations. Users moving from B to G may not notice, but don't expect new G stations to operate at peak efficiency until migration is completed.
At least initially, G products will be more expensive than B products. It may be prudent to limit initial G adoption to power users and bandwidth-intensive applications.
Enterprise gear is moving more slowly towards G. Proxim announced its first G products in February and Cisco does not plan to release G products until the standard is ratified. Organizations with existing WLANs may want to follow their vendor's migration timetable.
Even after G matures, there will be cases where A is preferable. For example, WLANs that suffer interference in the crowded 2.4 GHz band may benefit from moving to the 5 GHz band occupied by A. High density hot spots can achieve greater aggregate capacity with A due to the number of overlapping channels in the 5 GHz band.
In the long run, dual-band products are expected to be popular because they offer more flexibility. A+B products work in G networks – at B data rates. G products work in B networks, but not in A networks. Therefore, consumers that require dual-band flexibility may want to stick with A+B until A+G cards become available.
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