From: Kevin L Prigge <Kevin.L.Prigge-2@tc.umn.edu>
Date: Wed, 21 Aug 1996 14:29:15 +0800
To: eagle@eff.org
Subject: Re: Key Length Correlation
In-Reply-To: <9608201302.aa18129@deepthought.armory.com>
Message-ID: <321a391f26cd002@noc.tc.umn.edu>
MIME-Version: 1.0
Content-Type: text/plain


Jeff Davis said:
> I've read Blaze and diffie's paper on Semetric Key Length.  I'm currious
> how semetric key length correlates to public key cryptography length.  Does
> public key length have to be much longer, (assuming the algorithms are strong),
> to provide the same level of security as a shorter semetric key?  TIA   
> -- 

It's been calculated that in the case of PGP, to equal the work factor 
to brute force the 128 bit IDEA key would require a RSA key > 3000 bits.

Someone probably has a reference.

-- 
Kevin L. Prigge                     | "I rarely saw people sitting at
Systems Software Programmer         |  computers producing real code
Internet Enterprise - OIT           |  wearing ties." - Philippe Kahn
University of Minnesota             | (speech at Software Development '90)