Getting a grip on WLAN futures

Proxim talks wireless TLAs and security upgrades

The Register's Wireless LAN Channel

The wireless LAN world is a pretty bad offender when it comes to Alphabet Soup, what with 802.11b preceding 802.11a, and neither being the same type of thing as 802.11e*. So it was useful to hear Jan Haagh, a senior product manager in Proxim's WLAN division, talk through some of latest acronyms.

One to watch out for is WPA, or WiFi Protected Access. This will replace the original WEP wireless security standard, which turned out to be not very secure after all. Following on from WPA is 802.11i, due for ratification later this year, but Haagh warns that the two are rather different beasts.

"11i is so stringent that you pretty much have to throw away what you already have," he says. "WPA was designed as a software upgrade for existing hardware. It is an intermediate step to 11i and combines 802.1x authentication with TKIP encryption." The latter uses dynamic encryption keys, instead of WEP's crackable static keys.

On the topic of faster WLANs, Haagh says that 802.11g is "99% ready." However, even though the two standards use the same frequency, and 11g at 54Mbps is backwards-compatible with 11b, he recommends that the AP should have separate transmitters for each.

"A dual-slot architecture optimises throughput in mixed networks - 11g's backwards compatibility with 11b is very demanding on the performance side, so having two radios give much better capacity," he explains.

[Not everyone agrees, of course. Some 11g APs will drop everyone down to 11b speed as soon as an 11b device connects, but others such as US Robotics reckon they can connect everyone at the fastest speed possible.]

One other thing to watch out for is the intelligence moving out of the APs and into a centralised device. This approach should suit organisations with six or more APs, according to Haagh.

"The centralised architecture is driven by cost, as the APs can be much lighter," he says. "It also concentrates the intelligence close to the switch, gives the system enhanced functionality for management and mobility, and allows you to integrate wireless and wired network security."

*11e is the Quality of Service (QoS) standard, which is needed if you want to carry both voice and data.over the same wireless infrastructure. ®

The Register's Wireless LAN Channel

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