NonNullSet writes "Who would have thought that that something new could be said about how best to select passwords? Ross Andreson of Cambridge University and some of his colleages have performed new empirical studies and found some pretty non-intuitive results. For example: 1. The first folk belief is that users have difficulty remembering random passwords. This belief is confirmed. 2. The second folk belief is that passwords based on mnemonic prases are harder for an attacker to guess than naively selected passwords. This belief is confirmed. 3. The third folk belief is that random passwords are better than those based on mnemonic phrases. However, each appeared to be just as strong as the other. So this belief is debunked. 4. The fourth folk belief is that passwords based on mnemonic phrases are harder to remember than naively selected passwords. However, each ap- peared to be just as easy to remember as the other. So this belief is debunked. 5. The fifth folk belief is that by educating users to use random passwords or mnemonic passwords, we can gain a significant improvement in security. However, both random passwords and mnemonic passwords suffered from a non-compliance rate of about 10% (including both too-short passwords and passwords not chosen according to the instructions). While this is better than the 35% or so of users who choose bad passwords with only cursory instruction, it is not really a huge improvement. The attacker may have to work three times harder, but in the absence of password policy enforcement mechanisms there seems no way to make the attacker work a thousand times harder. In fact, our experimental group may be about the most compliant a systems administrator can expect to get. So this belief appears to be debunked."