From: khijol!erc@colossus.apple.com (Ed Carp)
Date: Fri, 20 Aug 93 14:36:40 PDT
To: bill@twwells.com (T. William Wells)
Subject: Re: cypher breaking and genetic algorithms
In-Reply-To: <CC22rC.q6@twwells.com>
Message-ID: <m0oTcyq-00022HC@khijol>
MIME-Version: 1.0
Content-Type: text


> Well, since I'm here, I thought I'd satisfy a curiosity of mine.
> Has anyone done any research, formal or informal, on the use of
> genetic algorithms to break cyphers? If not, would anyone care to
> discuss how it might be done?

As I recall, GAs are rather inappropriate for crypto applications, as they
tend to give rather inexact answers.  In a message where one wrong bit
could mean the difference between "en clair" and garbage, they are useless.
But for simple substitution ciphers, they can enable one to get "best guess"
clear - enough to make the message readable.  Hopefully. :)
-- 
Ed Carp, N7EKG			erc@apple.com			510/659-9560
                            anon-0001@khijol.uucp
If you want magic, let go of your armor.  Magic is so much stronger than
steel!        -- Richard Bach, "The Bridge Across Forever"