From: scrappo.reverb@juno.com (A L)
Date: Thu, 12 Sep 1996 18:02:41 +0800
To: cypherpunks@toad.com
Subject: An old _Discover_ article explaining RSA
Message-ID: <19960911.212157.4415.0.scrappo.reverb@juno.com>
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I had found this article in an issue of Discover I've had for a few
years. It is a comic strip-type article by Larry Gonick article
explaining,
in Layman's terms, the very basics of RSA. This article was
printed in the April 1992 issue of Discover magazine (some liberties
taken regarding pictures, etc.).

Box1:Prime Time
	featuring SEYMOUR Cloak-and-Dagger Mathematician!
	(sh!)
Box2:PRIME NUMBERS-numbers that can't be
	broken into a product of smaller factors-
	have always been one of the most amusing
	and USELESS topics in mathematics.
Box3:Then why are Banks, Businesses, Mathematicians, and Government
	SPY AGENCIES fighting over prime numbers?
	(STOP RIGHT THERE!)
Box4:It has to do with CRYPTOGRAPHY-secret codes.
	(The patriotic thing to do would be NOT to read one more word!)
Box5:In the computer age, cryptography is MATHEMATICAL: Inside the
	computer, every MESSAGE is a string of ONES and
	ZEROES: a number, in other words.
	(PLEASE!!!)
Box6:ENCRYPTING a message means scrambling this number,
	using a reversible formula based on a secret number
	or numbers called the KEY.
	message-->key-->cyphertext
	DECRYPTING the cyphertext is done by applying the
	key in reverse.
Box7:It would seem that both the sender and receiver need to know-
	and conceal-the key, but in the 1970's, WHITFIELD DIFFIE
	and MARTIN HELLMAN showed a way to MAKE KEYS PUBLIC!
	(Hippy-Diffie!)
Box8:Knowing how to SCRAMBLE, said Diffie, is not the same as
	knowing how to UNSCRAMBLE. Consider the egg!!!
Box9:Suppose a code had TWO KEYS, a scrambler and an UNSCRAMBLER...
	and suppose it was IMPOSSIBLE to compute one key from
	the other-in the sense that no computer could do it in less
	than the lifetime of the UNIVERSE???
	(crank crank crank)
Box10:You'd have an UNBREAKABLE CODE!
	(Wait... Almost got it...)
Box11:It works like this:
	Everyone owns a unique pair of keys. One remains private.
	But the other, public key is listed in a directory.
	To send me a message, you look up my public key and use
		it to scramble the message.
	My private key is the only way to unlock the message.
	Result:total secrecy and privacy!!
Box12:Diffie's idea soon became a reality, as three guys at M.I.T.
created
	a public-key algorithm known as RSA, from their initials.
	(picture)Rivest (picture)Shamir (picture)Adleman
Box13:RSA's unbreakability depends on the "impossibility" of FACTORING
	large numbers.
	(15? that's 3 x 5! Easy!)
	(3,447,981,101,346,271,113,552,476,003,201,
	119,181,244,551,900,123,549,822,344,722,436,001? um..)
Box14:It's not hard to find two large PRIME NUMBERS P and Q. But if
	I hand you their PRODUCT, PQ, your supercomputer will
	never find P and Q again.
	(SOB!)
Box15:Under RSA, each user gets a 160 digit number, N, which is the
	product of two large primes, P and Q.
Box16:The number N is made public, while P and Q remain secret. A
	simple formula completes the encryption, which can't be cracked
	without FACTORING!
	(ngh)
Box17:The National Security Agency didn't like this! The spy bureau wants
	the ability to crack any code!
	(Your assignment Seymour: FACTOR FASTER!!)
Box18:But spies aren't the only ones who need cryptography! Anyone who
	transmits ELECTRONIC DATA wants to secure the information's
	integrity.
	(Why? What? This is an OPEN SOCIETY!)
Box19:Unbreakable public-key code would effectively
	Protect money transfers from tampering
	Shield sensitive business data from the competition
	Immunize software against viruses
	(Allow us to gossip securely by E-Mail!)
Box20:So-After years of resisting Public-Key systems, the government
	in 1991 finally endorsed one as a new NATIONAL STANDARD.
	(I WAS WRONG! EMBRACE ME!)
Box21:Unlike RSA, however, the government's DSA (Digital Signature
	Algorithm) depends on a single, government-issue PRIME
	NUMBER.
	(Take a P! Not any P!)
Box22:Within months, mathematicians had shown how this could give
	the government, and the government alone, the ability to
	BREAK the code-and so the argument continues...
	(Trust, Where is the trust??)