Initialization Vectors

In cryptography, an initialization vector (IV) is a block of bits that is required to allow a stream cipher or a block cipher to be executed in any of several streaming modes of operation to produce a unique stream independent from other streams produced by the same encryption key, without having to go through a (usually lengthy) re-keying process. IV's are commonly referred to in wireless network hacking, more specifically WEP hacking, where a hacker fakes association with a wireless access point and generates IV's that are used to crack the WEP key of the network.