A similar issue came up when the (DES) Data Encryption Standard became a (FIPS) Federal Information Processing Standard, q.v. http://en.wikipedia.org/wiki/Data_Encryption_Standard There were suspicions that NSA had back-door access to the keys, possibly via the chips with which IBM were involved. I do not know how this was resolved: presumably nothing was proved, or I would have heard about it. A DES 56-bit key was cracked, and the aware world has I think moved on to Triple-DES. http://en.wikipedia.org/wiki/Backdoor_%28computing%29 discusses backdoors but not the DES/NSA scenario. Ken Thompson's 'Reflections on Trusting Trust', his Turing Award address (CACM 27.8 1984), is an 'ACM Classic' and worth a read. Guy