WEP - technical definition

(Wired Equivalent Privacy) An IEEE standard security protocol for wireless 802.11 networks. Introduced in 1997, WEP was found to be very inadequate and was superseded by WPA, WPA2 and 802.11i. Its authentication method was extremely weak and even helped an attacker decipher the secret encryption key. As a result, WEP authentication was dropped from the Wi-Fi specification.

Passwords Are Required
WEP uses passwords that are entered manually at both ends (see preshared keys). Using the RC4 encryption algorithm, WEP originally specified a 40-bit key, but was later boosted to 104 bits. Combined with a 24-bit initialization vector, WEP is often touted as having a 128-bit key. See WPA, 802.11i and initialization vector.