-----BEGIN PGP SIGNED MESSAGE----- At 09:34 AM 9/23/97 +0100, Ross Anderson wrote:
There is also the point that the vast majority of encryption keys are actually used for authentication rather than confidentiality. The keys that encrypt your bank card PIN en route from the ATM to the bank, the keys in your satellite TV decoder, the keys in your gas meter and your postal meter - in fact the majority of all DES keys in use - are about authentication. In theory most of them could be replaced by digital signature mechanisms but given the size of the installed base, it won't happen anytime soon.
For what it's worth, I once got an opinion from NSA's export control office that I could use any kind of crypto I wanted (e.g., even triple-DES) if all I'm doing is protecting a channel carrying a password (like the PIN), because that's an authentication function and therefore to be encouraged. I didn't get this in writing, however, so I'd have to go for it again. - Carl -----BEGIN PGP SIGNATURE----- Version: PGP for Personal Privacy 5.0 Charset: noconv iQCVAwUBNCkgkFQXJENzYr45AQF9EAP+Lx54AGJVvr9nOgGEaFYgMyTYFsalnPV9 3ZhqCIc6DDbjGBPf7r20SYUwz+3mhLeGLjlHleltXoT/coAChL/vSnqL0Q9/gpRI w11Sg32vFi/6Fr8fNWgEcMtmuIIZS/QSRt3hj8p0cc6UN2bjWevD97/brWhVjWYl hNdlUrgPpHw= =l1tu -----END PGP SIGNATURE----- +------------------------------------------------------------------+ |Carl M. Ellison cme@cybercash.com http://www.clark.net/pub/cme | |CyberCash, Inc. http://www.cybercash.com/ | |207 Grindall Street PGP 2.6.2: 61E2DE7FCB9D7984E9C8048BA63221A2 | |Baltimore MD 21230-4103 T:(410) 727-4288 F:(410)727-4293 | +------------------------------------------------------------------+