signal is amplified and can be directed much more efficiently than a regular antenna. Instead of going equally in all directions it is “pointed” through the cantenna.
WEP cracking is really dependent on the manufacturer of the router. Linksys, D-link, and others still use the shit algorithm for encryption. But the whole point is that 802.11 is an open standard so they threw this flawed encryptions scheme on it. An arp injection attack brings the attack time down, lowest I’ve seen is around 3 minutes under optimal conditions. Goddamn macs cant do arp injection so it takes around 5 days IF you get A LOT of traffic moving through.