re off the shelf cheap des keyseach machine was re corporate acceptance of the wiretap chip in article apr ulysses att com smb research att com steven bellovin writes responding to claims about skipjack cracking engines thousands tens of thousands do some arithmetic please skipjack has possible keys let s assume a brute force engine like that hypothesized for des microsecond per trial million chips that s trials per second or about years for trials well maybe they can get chips running at one trial per nanosecond and build a machine with million chips sure only years for each solution i think i should also point out that the mystical des engines are known plaintext engines unless you add a ton of really smart hardware the plaintext is digitized voice and exists for a very short time probably in a couple inches of copper tops it s flatly not available your bug in my office can hear my voice and even digitize it but it s going to get a different bitstream it is horribly naive to suppose that regular folks can figure out how to crack skipjack or clipper based telephones i m certainly not devoting a great deal of thought to it andrew molitor
