The most obvious security problem with wireless LANs is also their chief virtue: Data can be received by anyone who is anywhere in range of the signal. The signal passes through walls, outside buildings, and off property boundaries. Attackers can both capture and transmit wireless signals provided they are within range. Powerful antennae allow attackers to receive and transmit 802.11 packets from up to several miles away.
An attacker uses reconnaissance to discover and analyze the targets of his attack. During this analysis, he tries to determine what protocols and security mechanisms are being used so that he can choose which tools to use to attack them. Although sniffing and wardriving are not attacks and have legitimate ...