From: Dave Emery <die@pig.die.com>
Date: Mon, 25 May 1998 11:22:38 -0700 (PDT)
To: cypherpunks@toad.com
Subject: [rttyman@wwa.com: [Spooks] Digital Steganography]
Message-ID: <19980525142146.B3293@die.com>
MIME-Version: 1.0
Content-Type: text/plain


----- Forwarded message from Bob Margolis <rttyman@wwa.com> -----

Date: Mon, 25 May 1998 12:54:47 -0500
From: Bob Margolis <rttyman@wwa.com>
To: spooks@qth.net
Subject: [Spooks] Digital Steganography

Secret Messages: Army Researchers Discover Advance Technique To Relay
   Information

   Army researchers bring new meaning to the phrase, 'a picture's worth
   a thousand words.'

   An advanced technique for hiding secret messages inside of images is
   a new discovery made recently by U.S.Army Research Laboratory (ARL)
   researchers and a Federated Laboratory partner from the University of
   Delaware.

   "As a method to provide secure communications on the battlefield, we
   are pursuing research in the area of digital steganography," says
   Lisa Marvel, an electronics engineer at ARL's Information Science &
   Technology Directorate.

   The Greek word, steganography, means covered writing.

   "Our initial system involves embedding hidden messages within images.
   Images that are typically transmitted over the battlefield, such as
   weather or terrain maps," she says.

   The hidden message, be it an authentication mark, time stamp or new
   orders to a commander, is completely undetectable and resistant to
   removal and arbitrary decoding. Only the intended recipient holding
   the 'key' can decode the hidden message.

   Consider for a moment the impact of this new capability. U.S. Forces
   are pent behind enemy lines and out numbered three to one. The
   commander is not able to communicate their situation to base, because
   an enemy listener is detected on the communication network.

   The commander orders a message be sent through the Stego
   Communication System. In less than 45 seconds a soldier types the
   message on a laptop computer, hides the message in a map and sends it
   to base undetected. U.S. troops are deployed with enemy forces
   unaware of the impending ambush. U.S. soldiers are recovered with no
   casualties.

   Steganography is part of ARL's defensive information warfare efforts
   under the Federated Laboratory Program. The research began in
   February 1997 and is projected to continue over the next two years.

   "The result of this basic research can be packaged as software that
   can run on any laptop, anywhere. The main focus for the next two
   years is to increase the amount of undetectable information that we
   are able to hide in an image and develop techniques that make
   messages even more resilient to any kind of corruption," Marvel says.

   Typically, basic research is projected for use five years out. But,
   Marvel says this particular work is implementable in a shorter
   timeframe. She predicts that when the research is completed in two
   years it will just be a matter of software rewrite and packaging,
   which will take about 6 months before it can actually become a true
   product.

   Marvel credits the collaborative work, commissioned by the Federated
   Laboratory, for the successful progress of the project. Marvel
   developed the initial test system, guided by Dr. Charles Boncelet,
   Professor of electrical engineering at the University of Delaware.

   "Dr. Boncelet brought in some specific insights and his expertise in
   random signals and noise truly contributed to the success of the
   work," Marvel says.

   Dr. Charles Retter another ARL engineer provided his expertise in low
   rate error correcting codes, "which is key to how we are able to
   extract the message from the image without having the original
   image," she adds.

   Digital steganography is a new topic of research that incorporates
   ideas from communications, cryptography, information theory, and
   signal processing. So far, very little information exists in the
   formal literature on this topic, unlike digital watermarking which is
   currently a very active area of research.

   Although similar, steganography differs from watermarking in several
   aspects. For example, digital watermarking is used to embed a visible
   or invisible signature into a medium in order to indicate ownership,
   such as the station insignia seen in the bottom corner of a
   television screen during programming.

   Steganography, on the other hand, is used to encode a hidden message
   typically much larger than a signature, Marvel explains.

   In preparing to file for a patent, the ARL researchers are conducting
   the required background research on the prior art.

   "We found that a few basic techniques used over the years work pretty
   well, but are not nearly as sophisticated or complete. It appears
   that our technique is unique," Marvel concludes.

---
Submissions spooks@qth.net

----- End forwarded message -----

-- 
	Dave Emery N1PRE,  die@die.com  DIE Consulting, Weston, Mass. 
PGP fingerprint = 2047/4D7B08D1 DE 6E E1 CC 1F 1D 96 E2  5D 27 BD B0 24 88 C3 18