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From: chongo@nsc.uucp (Curt Noll)
Newsgroups: net.crypt
Subject: Re: Cracking public - key encryption schemes such as RSA
Message-ID: <363@nsc.uucp>
Date: Fri, 26-Aug-83 21:39:39 EDT
Article-I.D.: nsc.363
Posted: Fri Aug 26 21:39:39 1983
Date-Received: Mon, 29-Aug-83 01:16:06 EDT
Organization: National Semiconductor, Sunnyvale
Lines: 23

from my understanding on this topic, the RSA system has not been cracked,
nor has a `proof' shown it to have a given level of security.  the knapsack
system as been smashed to bits by methods using repeating fractions.
(an APPLE cracked the knapsack cypher challenge in a matter of hours
to give you an idea of how bad it was cracked)

i have used the RSA system quite a bit.  while i dont have my notes in front
of me, i do seem to recall alot of misinformation, and disinformation (some
by our government) given about RSA.  i offer some thoughts:

1) every non-trivial RSA system will generate a cyphertext which is the
   same as the plaintext.  some systems using primes can result in
   every cyphertext being the same as every message!  (not a very good
   security eh?)

   one can select a subset (a sizeable fraction of the primes) which will
   generate only 9 `non-mixed' cypertexts.

2) in general, not much is known about how well mixed the cyphertexts
   are from an RSA system.  #1 deals with totally non-mixed items, but
   where the encode function is equivalent to a trivial function.

chongo /\../\