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Re: 2047 bit keys in PGP
> From: Scott Brickner
> To: Cedric Tefft
> Subject: Re: 2047 bit keys in PGP
> Date: Thursday, January 04, 1996 3:41PM
>
> Return-Path: <[email protected]>
> Message-Id: <[email protected]>
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> To: Cedric Tefft <[email protected]>
> Subject: Re: 2047 bit keys in PGP
> In-Reply-To: (Your message of Thu, 04 Jan 1996 14:12:00 PST.)
> <[email protected]>
> Date: Thu, 04 Jan 1996 15:41:51 -0600
> From: Scott Brickner <[email protected]>
>
----------------------------------------------------------------------------
--
> Cedric Tefft writes:
> > If his algorithm effectively cuts my keyspace in half, I need to make it
> >twice as large as I would need if my attacker's best algorithm were brute
> >force.
>
> Um. No. If his algorithm cuts the keyspace in half, you only need to
> make it one bit larger.
>
You are correct. I'm afraid I was thinking one thing and typing another.
What I meant to say is that the attacker has an algorithm that effectively
cuts my keySIZE (instead of keyspace) in half, i.e. his algorithm requires
him to try on average only 2^1023 keys (instead of 2^2047 for a brute force
attack) to crack my key of 2048 bits.
Thanks for pointing this out.
"Who needs encryption when their thoughts are unclear in plaintext?"
- Cedric