licensing this thread brings up the more general question can any crypto implementation for which highly publicly scrutinized source code is not available ever be trusted after ibm had invented the des and the nbs had advertised for proposals but before ibm had decided to respond i argued strenuously that they should not they should keep it proprietary the biggest proponent of proposing was dr lewis branscomb dr branscomb was the ibm chief scientist and had come to ibm from nbs fortunately for all of us dr branscomb understood the answer to the above question much better than i he realized how difficult it would be to gain acceptance for any cryptographic mechanism because of the necessary complexity publicity would not be sufficient and neither would authority in fact it has taken both of those plus more than years we have also had independence the des was solicited by nbs invented and proposed by ibm and vetted by nbs it has also been examined and vetted by experts like adi shamir who are not subject to influence by any of these even now there are still people posting on this list who do not trust the des in spite of all the time all of the analysis and all of the public scrutiny of course it is just this point that nist misses when it attempts to gain acceptance for a novel mechanism developed in secret on the basis of authority alone we had a long thread here about whether or not the nsa can break the des that is a silly question at some cost and in some time they can break anything the important question is at what cost and in what time the fundamental strength of the des and rsa are not nearly so important as what we know about their strength as long as we understand the cost and duration for an attacker then we can use them in a safe way at this point we may never replace either because of the inability of any successor to overcome this knowledge gap des and rsa are among the most significant inventions of the century and the most important inventions in the history of cryptography we are damned lucky to have them william hugh murray executive consultant information system security locust avenue suite new canaan connecticut att wmurray whmurray at dockmaster ncsc mil
