Path: utzoo!utgpu!water!watmath!clyde!rutgers!cmcl2!brl-adm!brl-smoke!gwyn
From: gwyn@brl-smoke.ARPA (Doug Gwyn )
Newsgroups: sci.crypt
Subject: Re: Request for opinions: canadian cryptographic standard.
Message-ID: <7564@brl-smoke.ARPA>
Date: 27 Mar 88 11:45:38 GMT
References: <2463@geac.UUCP> <8497@reed.UUCP> <821@bucket.UUCP>
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 17

In article <821@bucket.UUCP> leonard@bucket.UUCP (Leonard Erickson) writes:
>So if I get both and run my data thru the in sequence, would that mean that
>neither NSA nor it's Canadian equivalent code crack it without either luck
>(finding the other guy's backdoor) or sharing their black boxes (which
>defeats the purpose of having seperate black boxes)?

I don't know whether there is a "back door" to the DES, but from its
structure I rather think not.  In any event, the combination of two
complex cryptosystems is not necessarily theoretically much more secure
than using just one, but any specialized automated procedure for
cracking one of the "standard" systems that some secret agency may have
set up would not work when applied to the combination.  Whether this
would deter them depends on how important they consider reading your
traffic to be.  If it's just a "personal" application, I doubt they'd
bother to try cracking your traffic, since there would be insufficient
return for the resources invested.  Ultimately, you're protected by
economics!