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Crypto
Author: Steven Levy
Publisher:  Viking 
ISBN:  0-670-85950-6
Rating: Excellent
Reviewer: topeka <[e-mail]>

Synopsis: This January, Steven Levy will make the next installment in 
his history of the technological events  of the past quarter century.  
<b>Crypto: When the Code Rebels Beat the Government</b>  is an 
excellent account of the events that delivered cryptography out of the 
hands of governments and the NSA and into the hands of the people 
who made it happen.

<p>
The first time I heard the term "elegant" applied to a technical problem 
was a bit of a revelation for me.  Until then, elegance, to me, was a 
visual quality that could only be achieved by painters and poets.  
When I began to see the elegance in solutions to technical and 
mathematical problems, I was hooked into a world of intellectual 
curiosity.  Cryptography immediately filled the mold of a highly 
complex and technical problem with a beautiful and elegant solution 
when it was first explained to me several years ago.  The idea clicked 
again when I read Raymond's <a 
href="http://www.tuxedo.org/~esr/writings/cathedral-bazaar/"> The 
Cathedral and the Bazaar</a> and equated that elegance to 
"scratching a particular itch".  This intellectual curiosity seems to 
drive the open source community.
</p>
<p> 
However, in 1967, when James Ellis of the secret British agency, 
GCHQ, first came up with the idea of public key cryptography, his 
theory was buried.  Until then, solutions to cryptographic problems 
were a dirty process. If it was easy to create a cipher, than it was just 
as easy to break it.  As such, Ellis's breakthrough was simply too 
pretty to be trusted and as a result, it lay locked away until 1997.  <a 
href="http://www.echonyc.com/~steven">Steven Levy's</a> new 
book, Crypto is the story of the individuals who transformed 
cryptography from a dirty art, which only the most elite governments 
dabbled in, to an elegant mathematical solution available to the public 
in hundreds of different forms.  It was all done by a community of 
individuals who preached openness and sought out elegant solutions to 
tough, technical problems.
</p>
<p> 
Levy starts out his story in the same place as he started with an earlier 
famous work, at the Massachusetts Institute of Technology.  He 
narrates the story of Whitfield Diffie, the co-creator of public key 
cryptography.  Starting in 1969 as Diffie sought shelter from the 
Vietnam war working for a defense contractor, Levy discusses Diffie's 
transformation from examining ideas about cryptography as merely a 
hobby, to an all out obsession.   Diffie is transformed from a man 
thinking about cryptography on the weekends to a man criss-crossing 
the country in one run-down Datsun after another, searching for any 
and every piece of information about cryptography. Diffie would not 
broach the wall of cryptography until he was pointed to another 
cryptography source in California who seemed to be investigating the 
same concepts as Diffie.  Levy chronicles the fateful partnership that 
occurred with Marty Hellman and the subsequent invention of public 
key cryptography, at least its theory.
</p>
<p> 
During this time period, there were few works published on the subject 
of cryptography.  In fact, only government agents and a few privileged 
defense contractors were able to expend meaningful resources on 
crypto research.  It seems that while Levy's work is a story of the 
people who waged a war to bring crypto to the public, it is also the 
story of that wars' enemy, the National Security Agency.  The 
cryptography bureaucracy, gaining most of its resources during the 
Second World War, had built quite a palace around anything that 
involved codes.  In the years to come, the NSA would fiercely defend 
its position of strength.  From its early attempts to classify David 
Kahn's famous work, <I>The Codebeakers</I>, to its involvement in 
the creation of the Digital Encryption Standard and its invention of the 
Clipper Chip. As <I>Crypto</I> defines it, the spooks were able to 
keep their lock on cryptography by invoking a mentality of "if only 
you knew what I know..." in classified briefings to politicians and 
contract negotiations with defense contractors like IBM.  What the 
NSA never expected, was for anyone to try and find out what it was 
that they knew.  With the publishing of the Diffie-Hellman paper, 
"New Directions in Cryptography," one of the NSA's most viable 
opponents would begin their work where Diffie and Hellman's 
theories left off, implementation.
</p>
<p> 
Ron Rivest, Adi Shamir and Leonard Adleman, through a four-month 
period of intense brainstorming, would eventually implement and 
patent the Diffie-Hellman concept of public key cryptography while 
working as faculty at MIT.  As Levy chronicles it, the algorithm, 
which would become popularly known as RSA, was named for the 
order in which each mathematician gave to the project.  Rivest, who 
spearheaded the search for the implementation was listed first and 
Adelman, who merely poked holes in Rivest and Shamir's proposals, 
had to be convinced that he had even contributed enough to the project 
to be listed on the paper.  Until this point, the description of 
cryptographic algorithms in scientific texts had always been done 
using letters of the alphabet to depict members in a cryptographic 
exchange.  The creators of RSA introduced the now famous 
cryptographic characters, Alice, Bob and the unruly Eve, to describe 
their new breed of algorithms.  Levy is able to highlight the mentality 
of the three mathematicians, some of which at first, thought the 
problem was nothing more than a clever puzzle and too grounded in 
the real world to be successfully dealt with by mathematicians.   He 
shows their transformation to the church of cryptography, as the 
elegance of the new algorithms would prove as beautiful as the 
theorems of Gauss and Euclid. 
</p>
<p> 
The story continues with RSA Data Security, the vehicle Rivest would 
use to commercialize his algorithm.  To talk about RSA Data Security 
is to talk about patent use.  Both the Diffie-Hellman algorithm, as well 
as RSA, were actually patented by Stanford University and MIT, 
respectively.  When the patents were granted, those Universities then 
had the option to either free the patents or restrict them.  As history has 
painfully shown, they did not choose to free them.  RSA Data security 
was built on this decision -- an MIT patent.  It was sometimes difficult 
to read this section of the book with the same exuberance that Levy 
writes about it.  Nonetheless, it is a reminder of the state of our 
intellectual property laws today in the United States.
</p>
<p> 
Levy's narration eventually leaves the story of RSA to tell that of Phil 
Zimmerman, someone who could rightly be called a crypto-anarchist.  
Once again we are treated to an in depth discussion of the motivation 
that created <a href="http://www.pgpi.org/">Pretty Good Privacy</a>.  
Levy contrasts the use of legal patents by RSA Data Security to bring 
encryption to the masses, to the complete ignorance of them by 
Zimmerman in his creation of PGP to achieve the same goal.  
</p>
<p> 
Finally, in my favorite section of the book, Levy discusses the 
controversy that surrounded a device known as the Clipper Chip.  It 
was originally invented by the NSA as a complete key-escrow system, 
named the Capstone Chip.  Later, as AT&T attempted to market the 
first encrypted telephone device, the Capstone chip became the Clipper 
Chip as the FBI and other Executive branch officers rushed to 
implement a brain-dead subset of the original system before the AT&T 
device made it to market.  An entirely amusing fiasco, Levy lays the 
entire story out from beginning to end. 
</p>
<p> 
Lastly, includes an epilogue telling the story of the British agents at 
GHCQ, who beat Whitfield-Diffie and RSA