From: poier@sfu.ca (Skye Merlin Poier)
Date: Fri, 28 May 93 21:31:16 PDT
To: cypherpunks@toad.com
Subject: Modified Vigenere encryption?
Message-ID: <9305280735.AA22115@malibu.sfu.ca>
MIME-Version: 1.0
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I was just thinking... What if one were to use Vigenere encryption with a key
at least as long as the message (therefore making the incidence of coincidences
irrelevant)? A key made of, for instance, words strung together from a dictonary
selected pseudorandomly? 

Are there other weaknesses in the Vigenere system that are escaping me? Perhaps
one could use (in the pseudorand words example) distribution / transition / 
equilibrium proabilities in the english language? If so, are there any other
options for generating a long key without the need for a truly random key (which
would make using the Vigenere table pointless because it would just be an one-
time-pad)?

Also, what are the weaknesses of the Playfair cypher? My texts mention it, but
don't say much of anything other than how it works...

Just pondering at odd hours...
Skye
- --
- -----====> Skye Merlin Poier <====----- 
Undergrad in CMPT/MATH (Virtual Reality)       ||||      ||||
          email: poier@sfu.ca                  p-OO <--> OO-q   THINK
   PGP Public Key available on finger           \==      ==/


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