Wireless LAN migration issues
If you are interested in deploying wireless LANs, youve likely heard rumblings about newer, better, faster wireless LAN technologies and standards coming down the pike. You also may have wondered what this mean in terms of investment protection -- particularly considering that wireless LANs are significantly more expensive than their wired counterparts at this juncture.
Weve discussed IEEE 802.11b several times in this newsletter. IEEE 802.11b is the current standard for 11M-bit/sec business LANs that operates in the 2.4-GHz spectrum range. There are three contenders being groomed as 802.11bs higher-speed successor:
* IEEE 802.11g basically doubles the current speed to 22M bit/sec. Championed by Texas Instruments, it operates in the same spectrum range as IEEE 802.11b, so it holds the possibility of backward-compatibility. In the spirit of 10/100M bit/sec wired Ethernet cards, speeds would default to the lower, 11M-bit/sec rate in a mixed network.
* IEEE 802.11a, which will run in the 5-GHz band, will offer 20M to 24M bit/sec at 802.11bs current 300-foot ranges. It promises to also offer up to 54M bit/sec at shorter distances. 802.11a and 802.11b use different frequencies, and thus hold no possibility of backward compatibility. Cisco and Lucent favor IEEE 802.11a.
* HiperLAN/2, an international favorite, is also slated to run at 54M bit/sec speeds in the 5-GHz range and is being backed by companies such as Ericsson, Philips and Nokia. As with 802.11a, the frequency change puts the kibosh on backward compatibility.
So if you have IEEE 802.11b LANs now (or intend to buy them soon), what happens to your investment? Which gear will work with which new technology remains to be seen, though it should begin to become more clear at the end of this year. Meanwhile, you could rent equipment with no more than a 2-year lease. Some vendors, such as Proxim, have built wireless LAN architectures that future-proof at least part of your investment as technology changes. Ill discuss this option next time.