From: "Kent Hastings" <kent_hastings@qmail2.aero.org>
Date: Wed, 11 Aug 93 11:22:21 PDT
To: cypherpunks@toad.com
Subject: New Chaos?
Message-ID: <199308111819.AA04314@aerospace.aero.org>
MIME-Version: 1.0
Content-Type: text/plain


                      New Chaos?
John Gilmore wrote:
  
>EE Times, Aug 9, 1993, p. 31 reports that "MIT's Research Lab of
>Electronics is creating new signal processor designs, based on chaos
>theory, that could open up a simple route to secure communications.
...
>The new designs use a recent discovery called synchronized chaos to
>transform a meaningful signal into what only seems to be random
>noise...

I saw something like this in the latest Scientific American, but is 
it new??

From my survey of spread-spectrum techniques, this 1950's approach
to signal hiding is called a "Transmitted Reference." Random thermal
noise in a resistor was transmitted in one band, and the same noise
mixed with a message was sent in another. The receiver would take the
the difference between the two noisy signals to get the message.

Although casual snoopers would be thwarted, the key is broadcast 
openly, therefore this should not be considered secure. Mix it with
modern Stored Reference techniques like frequency-hopping, direct-
sequence, and time-hopping and you might get a great hybrid system.

Are there any freeware spread-spectrum designs, analogous to PGP, to 
solve the physical data communications problem? Encryption is great,
but the phone company is enemy territory. bypass. Bypass. BYPASS!!!!

Kent <jkhastings@aol.com>