IP: Rivest's Wheat & Chaff - a crypto alternative (NYI)

[Dave Farber <farber () cis upenn edu>]

From: Vin McLellan <vin () shore net>
fyi: Rivest shakes the foundation (again!) _Vin
-----


"Scientist finds new way to scramble data"
Saturday, March 21, 1998
New York Times


SAN FRANCISCO -- One of the nation's leading computer scientists
has proposed a novel technique for scrambling data that could
circumvent government export policies aimed at limiting the
foreign sale of encryption technology.


The technique, which was described last week in an Internet
discussion among computer researchers, was introduced by Ronald
Rivest, a computer scientist at the Massachusetts Institute of
Technology and one of the inventors of the most widely used
commercial encryption scheme, RSA.


The new approach, which is described in a short technical paper
that has been posted to Rivest's MIT Web site
(http://theory.lcs.mit.edu/ ~rivest/chaffing.txt), is described
as ``chaffing and winnowing'' digital information instead of
encrypting it.


According to Rivest's paper, it is possible to hide a message by
breaking it into packets that are then secretly identified as
good information, or ``wheat,'' and gibberish, or ``chaff,'' in
such a way that an eavesdropper cannot distinguish the two.


Because the individual packets would not be encrypted, Rivest
said, such a system would circumvent current export restrictions.


The two principal ways of communicating in secret are encryption
and steganography. Steganography uses computer techniques to
embed a secret message in a document like a digital image. In
encryption, secret information is encoded using functions that
require difficult mathematical tasks to decode, and it has become
the standard way of transmitting secret information
electronically.


There are no restrictions on the domestic use of this technology,
but the government has been trying to force the industry to adopt
standards that would permit law-enforcement officials to have
mathematical keys allowing them to decode messages without the
knowledge of the sender or receiver.


<snipped>


See: http://spyglass1.sjmercury.com/breaking/docs/062460.htm


-----
"Cryptography is like literacy in the Dark Ages. Infinitely potent, for
good and ill... yet basically an intellectual construct, an idea, which by
its nature will resist efforts to restrict it to bureaucrats and others who
deem only themselves worthy of such Privilege."
_ A thinking man's Creed for Crypto/ vbm.


*     Vin McLellan + The Privacy Guild + <vin () shore net>    *
  53 Nichols St., Chelsea, MA 02150 USA <617> 884-5548