From: nobody@alpha.c2.org (Anonymous)
Date: Sat, 28 Oct 1995 21:15:38 +0800
To: cypherpunks@toad.com
Subject: Re: Diffie-Hellman Key Generation
In-Reply-To: <Pine.3.89.9510271616.A410-0100000@unicorn.com>
Message-ID: <199510281301.GAA12933@infinity.c2.org>
MIME-Version: 1.0
Content-Type: text/plain


> Finally, I'm basing this on comments in 'Applied Cryptography' that D-H
> keys should be at least 512 bits and preferably 1024. How does the
> difficulty of breaking a D-H exchange with a 512 bit key compare to
> breaking a 512 bit RSA key ?

Calculating discrete logarithms is a bit more difficult than factoring.
So a 512-bit DH modulus will give you somewhat more security than a 512-bit
RSA key.  I'm not sure how much, probably not a lot.