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 69 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.
0 comments:
Post a Comment