From: Michael Johnson <mpjohnso@nyx.cs.du.edu>
Date: Tue, 28 Sep 93 14:36:22 PDT
To: Carl Ellison <cme@ellisun.sw.stratus.com>
Subject: Re: Challenge: break the MPJ Encryption Algorithm
In-Reply-To: <9309282029.AA26018@ellisun.sw.stratus.com>
Message-ID: <Pine.3.05.9309281542.A16613-a100000@nyx>
MIME-Version: 1.0
Content-Type: text/plain




On Tue, 28 Sep 1993, Carl Ellison wrote:

> Is each of your 160 permutation arrays a self-inverse or do you generate
> different arrays for encryption and decryption?
No, they are not self inverses.  The inverses are computed from the
forward arrays to decrypt in electronic codebook mode.  Note that in some
chaining modes, the reverse mode isn't even needed, and the arrays could
literally be filled with random numbers.

                                  Mike Johnson
Long live the U. S. Constitution!