[8406] in cryptography@c2.net mail archive
Re: Perfect compression and true randomness
daemon@ATHENA.MIT.EDU (Paul Crowley)
Mon Jan 8 17:21:01 2001
To: "Arnold G. Reinhold" <reinhold@world.std.com>
Cc: Nick Szabo <szabo@best.com>, cryptography@c2.net,
burton rosenberg <burt@math.miami.edu>
From: Paul Crowley <paul@cluefactory.org.uk>
Date: 08 Jan 2001 21:55:49 +0000
In-Reply-To: "Arnold G. Reinhold"'s message of "Mon, 8 Jan 2001 09:41:09 -0500"
Message-ID: <877l45r9ne.fsf@hedonism.subnet.hedonism.cluefactory.org.uk>
"Arnold G. Reinhold" <reinhold@world.std.com> writes:
> In any case, as I tried to point out before, perfect compression, what
> ever it may be, does not prevent a know-plaintext attack.
Actually it does: if the compression is perfect with respect to the
document model of the attacker, and the plaintext is known, then it
compresses down to zero bits so the attacker learns nothing.
This supports your main point: perfect compression is a *much* less
realistic idea than true randomness!
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