From: Marshall Clow <mclow@owl.csusm.edu>
Date: Fri, 31 May 1996 06:38:27 +0800
To: "E. ALLEN SMITH" <EALLENSMITH@ocelot.Rutgers.EDU>
Subject: Re: Where does your data want to go today?
In-Reply-To: <01I5AWSFT3H48Y51NQ@mbcl.rutgers.edu>
Message-ID: <v03007002add37b0a637f@[206.126.100.99]>
MIME-Version: 1.0
Content-Type: text/plain


At 12:47 AM -0700 5/30/96, E. ALLEN SMITH wrote:
>From:	IN%"mclow@owl.csusm.edu"  "Marshall Clow" 29-MAY-1996 19:18:31.60
>
>>* Why encrypt before compression? If the encryption is any good, then the
>>encrypted data won't compress much at all. However, compression before
>>encryption has its own problems.
>
>	What problems does compression before encryption have? It at least
>seems to work for PGP.
>
Most compression schemes put a header/index on the front of the compressed data.
This makes recognizing the correct decryption very simple.

Call it a limited "known plaintext" situation.


-- Marshall

Marshall Clow     Aladdin Systems   <mailto:mclow@mailhost2.csusm.edu>

"We don't have to take it; never have, never will.
Gonna shake it, gonna break it; let's forget it: better still" --The Who, "Tommy"