re off the shelf cheap des keyseach machine was re corporate in article cmm jon gode ifi uio no jon lnes jon ifi uio no writes a person i know belonging to a research lab of a rivate company claimed to me during a priavte conversation that given the equipment in his lab he could crack a kerberos ticket in minutes to an hour he had access to rather powerful des hardware but not of an extraordinare kind i believe the attack was possible because of the amount of known plaintext in the ticket which itself constitutes a small message this was two years ago des is no longer usable for encryption of really sensitive data for a lot of purposes however it is still very adequate this sounds an awful lot like a password guesser not a weakness in des merritt and i pointed out this weakness in kerberos in a paper that came out about years ago in both computer communications review and usenix for that matter it was loudly discussed on the kerberos mailing list even earlier the problem has nothing whatsoever to do with des and everything to do with bad password selection i m perfectly willing to believe that there are cryptanalytic attacks possible on des i m quite dubious that private research labs know them and the parameters of a brute force attack are quite well established see for example the garon and outerbridge paper in the july cryptologia you re not going to do it in an hour with only rather powerful des hardware i ll leave the arithmetic as an exercise for the reader on average you ll need to do trials pick your own parameters for how fast the des engine runs and for how many such engines are used
