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Path: utzoo!mnetor!seismo!columbia!caip!andromeda!argus!ken
From: ken@argus.UUCP (Kenneth Ng)
Newsgroups: net.crypt
Subject: Re: randomly adding bits/bytes (compressing text before encryption)
Message-ID: <455@argus.UUCP>
Date: Tue, 19-Aug-86 18:01:56 EDT
Article-I.D.: argus.455
Posted: Tue Aug 19 18:01:56 1986
Date-Received: Thu, 21-Aug-86 04:02:53 EDT
References: <8608042018.AA04376@ucbjade.Berkeley.Edu> <7024@utzoo.UUCP> <251@decvax.UUCP>
Organization: NJ Inst of Tech., Newark NJ
Lines: 31

In article <251@decvax.UUCP>, minow@decvax.UUCP (Martin Minow) writes:
> In discussing ways to make data encryption more robust, several
> people suggested running the plaintext through LZ-compress first.
> utzoo!henry noted that compress prepends a fixed length (and content)
> header to the text, giving the codebreaker a hook into the encription.
[ edits ]
> One interesting thing about LZ -- one bad bit in the file may garble
> the entire remainder of the file.  This, in itself, should make the
> codebreaker's work harder.
> Martin Minow
> decvax!minow

True, unless you figure out which bit is wrong the receiver may never
be able to decrypt the rest of the message.  Now if you were to
purposely invert every XXX bit, hmmmm.


-- 
Kenneth Ng:
Post office: NJIT - CCCC, Newark New Jersey  07102
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Please resend any mail between 10 Aug and 16 Aug:
the mailer broke and we had billions and billions of
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