Where will these passwords be used?

If the passwords are truly random and not meant to be memorised by humans, then a very simple design is possible. Something like:

head -c 12 /dev/random | perl -e 'use MIME::Base64; print encode_base64(<>)'

On the other hand, if these passwords are meant to be used and memorised by humans, then I think you should look a the physcology of passwords, because if you give people random passwords they will either change them to easy to remember (and easy to crack) alternatives, or they will write them down, possibly on sticky notes attached to their monitors.

I have on my desk a copy of Security Engineering by Ross Anderson. Assuming you don't have access to a paper copy, then chaper 2, which includes a good discussion on passwords and password psychology is online.

From that book one good suggestion I saw was to randomly generate passwords in the form of alternating constanants and vowels, eg: cVcVcVcVc. That gets you a password that has a good amount of entropy, and cannot easily be cracked as it is not in a dictonary, but at the same time is easy to remember because it can be pronounced.

In reply to Re: Please Review First Program: Random Password Generator by chrestomanci
in thread Please Review First Program: Random Password Generator by hakkum

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