From peb at PROCASE.COM  Wed Jul 14 14:31:11 1993
From: peb at PROCASE.COM (Paul Baclace)
Date: Wed, 14 Jul 93 14:31:11 PDT
Subject: Relation between number theory and cryptography
Message-ID: <9307142130.AA08720@banff.procase.com>



These are very interesting questions.  I like the idea that the
physical work of encryption and decryption might be accounted for by
the increased entropy of the message.

>Is this affected by whether or not the key is known?

If the key is unknown, then the meaning or affect of the message on the
recipient is that of noise (or more accurately, "this message exists
but you can't read it"), but information theory has nothing to say about
this since it is concerned only with the communication itself.  Perhaps
the AI theory of Language As Action could be connected to information
theory (yeah, recast meaning as communication to a homunculous...)

Somewhere I have a paper on Maxwell's Daemon and Data Compression,
which seems related to this.  I can dig it up if you want a ref.  
(I haven't read it yet; it's ftp available.)


Paul E. Baclace
peb at procase.com