From: cme@ellisun.sw.stratus.com (Carl Ellison)
Subject: Strong Encryption
Organization: Stratus Computer, Software Engineering
Lines: 33
Distribution: world
NNTP-Posting-Host: ellisun.sw.stratus.com

I just posted this reply to comp.risks (answering RISKS DIGEST 14.53).
Summary: Re: [14.53 Mark Seecof] "key escrow"

>From: Mark Seecof <marks@wimsey.latimes.com>
>Subject: "key escrow" (Clipper Chip; RISKS 14.51)

>Advances in digital computing have made it possible for ordinary people to
>use powerful machine cipher techniques.

It is tempting (albeit chauvinistic) to believe that we have a new situation
here, thanks to our pet computers.  This is not true.  David Kahn's "The
Codebreakers", a history of cryptography, makes two things obvious:

1.	Cryptography is a spontaneous invention of private human individuals
	and has been going on for thousands of years.  [Teen-age slang and
	cipher inventions provide a modern example of this spontaneous
	creation.]

2.	The systems people created on their own were roughly as secure as (and
	sometimes more secure than) those used by military and diplomatic
	users *of that time* (although they seem very simple and insecure
	today). [e.g., In places, the Bible used a more complex simple
	substitution than Caesar did for his military dispatches, but before
	Caesar.]

I commend Kahn's book to all who might be interested.

-- 
 - <<Disclaimer: All opinions expressed are my own, of course.>>
 - Carl Ellison                                        cme@sw.stratus.com
 - Stratus Computer Inc.       M3-2-BKW                TEL: (508)460-2783
 - 55 Fairbanks Boulevard ; Marlborough MA 01752-1298  FAX: (508)624-7488
