Wireless Interception Distance Records
Don’t believe wireless distance limitations. Again and again they’re proven wrong.
At DefCon earlier this month, a group was able to set up an unamplified 802.11 network at a distance of 124.9 miles.
The record holders relied on more than just a pair of wireless laptops. The equipment required for the feat, according to the event website, included a “collection of homemade antennas, surplus 12 foot satellite dishes, home-welded support structures, scaffolds, ropes and computers”.
Bad news for those of us who rely on physical distance to secure our wireless networks.
Even more important, the world record for communicating with a passive RFID device was set at 69 feet. (Pictures here.) Remember that the next time someone tells you that it’s impossible to read RFID identity cards at a distance.
Whenever you hear a manufacturer talk about a distance limitation for any wireless technology—wireless LANs, RFID, Bluetooth, anything—assume he’s wrong. If he’s not wrong today, he will be in a couple of years. Assume that someone who spends some money and effort building more sensitive technology can do much better, and that it will take less money and effort over the years. Technology always gets better; it never gets worse. If something is difficult and expensive now, it will get easier and cheaper in the future.
RvnPhnx • August 8, 2005 3:12 PM
Being one of the amateur radio operators of the world I can say flat out that distance limitations have mostly to do with antennas and propagation conditions. A decent antenna can outdo a more sensitive receiver any day–it is easier to use a 3dB gain antenna than an amplifier or to make more sensitive circuitry (part of why the antenna was supposed to be part of the system to restrict an 802.11a/b/g connection to a limited region). I’ve heard of 200mW “connections” between ME and TX (on HF) before–if that says anything to those not well educated in the ways of RF.