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From: alain@elevia.UUCP (W.A.Simon)
Newsgroups: sci.crypt

Subject: Re: Braided Streams (an old hack)
Message-ID: <1991Jun18.114903.11733@elevia.UUCP>
Date: 18 Jun 91 11:49:03 GMT
Organization: The Electronic Path - Global Village
Lines: 34

I wrote MANY words about:
>      The Braided Stream Secure Communication System is a simple
>      and fast multiplexer system which provides high levels of
>      [ ... ]
>      to take the next bit to be output from, is determined by the
>      value of a bit, or group of bits, from the key stream.

	I am still convinced it is secure as you can get, but it is
	not as "new" as one might think.

	Some of us who already have a few wrinkles may remember an old
	trick of the cryptographer's trade, which consisted in using a
	perforated piece of cardboard, placed over some paper, through
	which one wrote a message.  Then the cardboard (it was called a
	grid) was removed and the blanks left on the piece of paper were
	filled in with garbage which was designed in such a way that it
	incorporated the message within an innocuous text.  One courrier
	would carry the grid, another one the paper.  The courrier carrying
	the paper was relatively safe as the message looked inoffensive.

	A variation consisted of using several such grids, none of which
	had any of its holes overapping any other grid's perforations.
	However, what was gained in efficiency (longer message on one
	piece of paper) was lost in safety for the courrier carrying the
	paper (it looked suspisciously like nothing normal).  The braided
	stream algorithm is nothing less/more than this old hack.

	I have not invented something completely new...  but at least
	we can make use of it, in new ways.


-- 
William "Alain" Simon
                                                   UUCP: alain@elevia.UUCP