A salt is really just a nonce: It doesn't have to be random or unpredictable; it just has to be globally unique so that attackers can't work to crack more than

A salt is really just a nonce: It doesn't have to be random or unpredictable; it just has to be globally unique so that attackers can't work to crack more than one password at once (or pick out identical passwords given a list of password hashes). We make it random because that's the only way we know how to create globally-unique numbers in our decentralized network. CBC-mode's IV really does need to be unpredictable by anyone who can influence the plaintext. Otherwise, you get things like this: http://www.youtube.com/watch?v=BTqAIDVUvrU http://www.youtube.com/watch?v=BTqAIDVUvrU