Re: Cracking decrypted file when knowing partial contents

From: Mark Wooding (mdw_at_nsict.org)
Date: 04/22/04 

Date: Thu, 22 Apr 2004 08:34:57 +0000 (UTC)

smith8328 t'kri @bellsouth.net <smith8328@bellsouth.net> wrote:

> The downfall of most encryption systems is that people are so quick to
> fall into habit. They start their messages with the same headings, use
> the same words, phrases, and sentences over and over again. This is
> especially true in Military Communications.

You are deluded. It is a minimal requirement of any modern encryption
scheme that it not be weakened by such redundancy in the plaintext.
More strongly, we require our encryption to be strong even if the
adversary is allowed to choose which plaintext messages we encrypt, in
the sense that he still not be able to match ciphertexts with plaintexts
except by length.

> That is why a one-time pad/cryptsystem is an absolute must.

Codswallop.

-- [mdw]

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