Re: EC Key Derivation Problem

Fabrice <fabrice.gautier@xxxxxxxxx> wrote:
You have a set of systems with the same Private Key (a) inside. If
you want to encrypt something for any of the system you use the Public
Key (A). Now, each system has a different Serial Number ("k"). You
want to encrypt something for one system only so you encrypt with B.

You are looking for identity-based cryptography. Your solution is too
simple, I'm afraid. If the serial number is public, it suffers from
an insider attack. If the serial number isn't public, you could just
as well use two different public keys, so what's the point?

Kristian Gjøsteen