Re: small authenticator

[staym]

Several people have suggested using a MAC; my problem is that the
opponent can reverse-engineer the chip and find the key.  I was hoping
to give the chips a public key and have it encrypt a challenge that I'll
respond to.  On my side, I'd need to prevent chosen-cipehrtext attacks.
-- 
Mike Stay
Programmer / Crypto guy
AccessData Corp.
mailto:[EMAIL PROTECTED]