If there were no salt, then someone could spend a few CPU years running every plausible password string through crypt() and make/distribute a reverse-mapping database. With a random salt, the size of such a database becomes much more infeasible to try to produce (you have to try each possible password with each possible salt string). But I doubt this is much of an issue these days, thanks to Moore's law and distributed computing.

There's also the fact that if two people have the same password, with (random) salt, that fact is not obvious by looking at their encrypted passwords. This is probably the most important reasoning: more information can be protected by using salt.

blokhead

In reply to Re: Salt -- Something I've Never Understood by blokhead
in thread Salt -- Something I've Never Understood by Cody Pendant

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