Brush up on 802.11

Farpoint Group |  Mobile & Wireless

** 802.11e: This WG is defining techniques for better time-bounded performance, also called QoS (quality of service). Such extensions are a little problematic, given the nature of the unlicensed radio bands (lots of potential for interference, limited power and range, and so on). But this standard is essential if we're going to make progress in the transmission of voice over IP and digital video, both of which clearly have a bright future on WLANs.

** 802.11i: This group is fixing the very visible security problems with the original standard, which is (in)famously susceptible to hacking and cracking. Most of what's likely to be in .11i is already available in the Wi-Fi Alliance's Wireless Protected Access (WPA) specification, which is now embodied in products from a number of WLAN vendors. Note that WPA isn't a de jure standard since it was not produced by a recognized standards body - but it's a good example of a de facto standard, a common technique for providing at least interim functionality in advance of (and sometimes as an alternative to) a "real" standard. .11i importantly adds to WPA the use of the Advanced Encryption Standard (AES), a very secure encryption technology already in use in many mission-critical applications.

** 802.11n: This recently-established effort is developing a PHY that will provide at least 108 Mbps in a single radio channel. Some vendors have provided non-standard (but still effective) extensions to allow two .11a channels to be ganged together, thereby nominally providing 108 Mbps. .11n will do this in one channel by defining a new PHY - one likely based on a previously-exotic radio technique called MIMO - multiple input, multiple output. Don't worry too much about exactly what that means for now - it requires a bit of explanation. But look for a Farpoint Group White Paper on this topic posted here in November - it's that important. In the meantime, check out Airgo Networks for more information. It is the first company to introduce a WLAN product based on MIMO.

.11e and .11i should be finished by mid-2004, and .11n sometime in 2005. But we just can't rush standards - good standards take a long time because of all of the alternatives that need to be considered, and a process that ensures broad support. Given the tendency of good standards to catalyze the creation of markets and even entire industries, it's in everyone's interest to be thorough. That's 802.11 - and they're not done yet.

Visit the official 802.11 site.

Copyright 2003 by Farpoint Group - All rights reserved.

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