Re: Help needed with a proof...

From: David Wagner (daw_at_taverner.cs.berkeley.edu)
Date: 04/29/04 

Date: Thu, 29 Apr 2004 03:19:52 +0000 (UTC)

Bartosz Zoltak wrote:
>Def 1.
>Let f(K,V) be a function, where V is known and K unknown.
>Let f have a property that relations between f(K,V1) and f(K,V2) are
>undistinguishable from random for V1 != V2.

I can't figure out how to assign any precise meaning to that statement.
I think you're going to need a more careful definition before you can
even get started. For instance, what do you mean by "relations between
... are indistinguishable from random"?

May I suggest reading material on provable security to learn how to
formalize definitions, assumptions, and security claims like this in
a more precise way? Bellare and Goldwasser's lecture notes are a fine
starting point.