Proving I'm not Bob.

[s1113645 at tesla.cc.uottawa.ca]

On Tue, 21 Nov 1995, David Scheidt wrote:

> What is this system?  I can't think of any system that wouldn't work if 
> rearranged so that instead of proving you aren't Bob, you simply don't 
> prove that you are.  It is true that they are not isomorphic, and that 
> could be a problem in some situations, but I don't see this as one of them.

Hal and Futplex pretty much described it. I figured a proof of non-identity
(if possible) would have saved one hell of a lot of messy authentication
in those cases when there is only one possible cheater (due to economic 
incentives) with many possible pseudonyms (or friends).