At 1:05 PM -0700 7/21/96, Simon Spero wrote:
[sorry Perry]
On Sun, 21 Jul 1996, David Sternlight wrote:
So is your comment. What was broken was not public key, but a particular key length (and by implication shorter ones). You can do that with just about any system, even a one-time pad, by brute force, but it won't buy you
Really? The only way I know of forcing a one-time pad is to use a hardware QM-based random number generator to generate every possible decrypt, thus creating a number of universes equal to the number of possible keys. Since you can't tell if you're universe is the right one, one should always verify the information obtained against a second source. IANAL, so I can't say if such a decrypt would count as probably cause.
Theoretically Simon is right. Nevertheless one-time pads have been broken through trial and error when they have been reused either out of laziness or force majeure. It's not a "monkeys in the British Museum" problem, since when you hit the right key sequences both encrypted text streams will fall cleanly out--otherwise the chances are overwhelming (given a decently long run) that one of the two streams will contain garbles or more likely be complete gibberish. It's a pretty simple computer program--all you need is a decent test for plaintext so you don't have to examine most of the test decryptions. David