April 25, 2019

Moving Closer to 802.11n - page 2

The Current State of Wi-Fi

  • August 27, 2007
  • By Carla Schroder

The evolution of the 802.11 standard could make a "reality" (not that anything is real about them) TV show, although a rather slow-moving one, with all of its conflict and intrigue: vendors developing their own competing, incompatible standards, jockeying for position on key committees, and trying mightily to have their own technologies adopted as the standard. Inevitably there are losers, who must then figure out how to make it possible for customers to upgrade legacy devices that aren't very old, or figure out a way to make them happy with purchasing bales of new gear.

802.11n, which is a subset of 802.11, is no exception. This is the MIMO, or multiple input/multiple output standard, which means using more than one antenna to increase bandwidth and throughput, and to extend range. (Don't confuse it with IEEE 802.16, which is long-range wireless networking, such as the "last mile" link for cable and DSL customers.) Early goals for 802.11n were ambitious, aiming for a 100Mbps WLAN standard by 2005. Here at the tail end of 2007 they've gotten as far as Draft 2.0, which was ratified in March 2007. This promises enticements such as 300Mbps and a range of 300 feet or more. Of course these are under ideal, perfect circumstances. If you mix 802.11n with 802.11a/b/g devices you'll get worse performance. Pure 802.11n networks perform the best.

You'll see ads boasting about devices being in compliance with "Draft 2.0 N". You'll also see evasive ads that say "Draft 802.11n." That doesn't tell you anything useful; what you want to know is can you mix-and-match different brands of interface cards and access points, or are you stuck with a single vendor to ensure that they'll work right and support all claimed features?

The thing to look for is officially certified devices. They should say something like "Wi-Fi CERTIFIED 802.11n draft 2.0." The Wi-Fi Alliance started certifying devices in June 2007, and manufacturers are eager to get their products certified, so you should be able to find a fair number of them in the market already. The Wi-Fi Alliance promises that Draft 2.0 N will be upgradeable to the final, official specification, so (theoretically) you're safe to start buying new gear.

Does purchasing certified devices guarantee that you'll be happy? Of course not. The devil is in the implementation, so as always there are good gadgets and cruddy gadgets. Some will work well, some will be more suited for target practice at the rifle range. I'll be looking out for the good stuff, and see Resources for links to helpful sites.

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