Crypto Fiction

Crypto novels are not that common. It's an esoteric subject that remains too small to even justify a niche title. Most of the treatments relate to only fringe interests.

There is a bit of a revival in crypto interest within the 90's science fiction genre. This can be traced back to authors who are influenced by the net, and geographically, it's clear that the main stars in this revival hail from or are influenced by the bay area and the cypherpunks movement.

For what it's worth, and to generate some commissions for Cryptix, I list here some crypto novels I've read. I rate them with bits of entropy, as a sort of reverse correlation with relevance. This rating isn't necessarily a view that this book is good or bad, just that it has a valued combination of readability and cryptology.

If you're looking for a present for that pesky relative that keeps asking "so, what is it that you do?" then you may find the answer below.


The leading light in the crypto novel scene has to be Cryptonomicon. This book, the fourth by trail blazing net author Neal Stephenson, is recent, having been published in mid 1999, and remains the only financial cryptography novel I have come across.

Cryptonomicon is an achievment, with a deserved 5 random bits of entropy, and it will become the novel against which all others are compared.

In brief, Randy Waterhouse and his startup companions embark on laying fibre around the Phillipines. Whilst building, new opportunities arise, chief of which is the combination of a local Sultan who wishes to build a data haven, and a rumour of a mountain of lost gold.

What lifts this book out of the ordinary, and indeed, camoflages the fairly simple plot, is the two intertwined threads separated by two generations. Randy's grandfather and a WWII team of crypto scientists work on dampening the Axis' ability to detect the Enigma cracks, coincidentally laying foundations for Randy's attempts to historically decrypt his forbears' trail. This historical story is fascinating, it takes the Enigma story well beyond what has been covered elsewhere.

The crypto content is superb. Mathematical basies, Turing and his bicycle, entropy, ciphers, are all woven into the story in a fashion that anyone with high school mathematics could understand.

Cryptonomicon has a deeper underlying significance that most will have written off as plot. Along the chase, Randy and his mates discover the opportunity of setting up a private currency, nominally based on the alleged gold. In crisis-ravaged Asia, where currencies fell as systemic failure swept through the banking system, gold- backed currencies, issued over the net, and cryptographically protected from all attackers, is the perfect entrepot for the issuance of private money.

Recall that private currencies disappeared about a century ago, as the newfangled Central Bank idea, born out of Britain, swept the civilised world to mark the 20th century as one of government money and government inflation. For various reasons which we'll gloss over here - read the book - the time of private currencies has come again.

But it was not in the prediction of a new financial world that the subtelty of Stephenson's research, and indeed unnamed advisors, shows. It is in the fact that the model he presents for a gold-backed currency is state of the art, in an art that was forgotten a hundred years ago, and indeed was only poorly understood then.

Readers could even be forgiven for accusing the art to be stateless, if it wasn't for the existance of at least one tiny Internet private currency, backed by gold. It was these guys, the e-gold private currency, who airshipped me a copy to read and respond. But there is no response possible, as Stephenson got it right. Prospective private currency issuers now have a novel that will save them from countless mistakes, and I now have an answer to that question, "so, what is it that you're doing that takes you so far from home?"

Digital Fortress

The NSA is the world's biggest employer of mathematicians, and as they are mostly employed on cryptology (the combined art of cracking codes and making codes) it is a great setting for a crypto novel.

Dan Brown first published Digital Fortress, back in 1998 or so, as the crypto wars were in full swing on the net. Netizens may recall the subtle coup de grace signed by outgoing President Clinton when he released out free and open source crypto from the clutches of the US government. That tiny window of opportunity both released all the Americans to join the crypto revolution, and crushed the rebellious spirit of cryptoplumbers everywhere.

The NSA once again proved it could see strategically far into the future, and Digital Fortress is about that world. Brown postulates that the NSA can crack all our codes with a massive but secret machine, until an ex-employee taunts them with an uncrackable algorithm. Confusion, misinformation, insiders fighting against each other, the book does a good job of representing an organisation so secret its hands can't count each other.

The crypto content is neither high nor accurate but the organisational picture is good for someone who knows little of this world. Even though it is written for a younger non-technical audience I rate it as 3 bits of entropy. Cryptoplumbers and geeks will be frustrated, and probably will enjoy his next novel more as the content is less likely to be as familiar: Angels and Demons. His later novel, the highly popular The Da Vinci Code does include some basic crypto content but I haven't read it as yet.


In all the fictional writings of cryptology, the Enigma machine takes pride of place. Enigma, is no different, but touches little on the machine itself.

Robert Harris, author of Fatherland, presents a story of spies and intrigue set amongst the paranoic secrecy of Bletchley Park. Like Cryptonomicon, the historical protagonist is a mathematician at the core of the code breaking effort.

This story is cryptologically valuable for its description of Bletchley Park, even to the workflow and passage of the information through the now quaint series of human I/O devices, computers, and analysts.

As a novel, it is well written and entirely readable, falling within the class of WWII / spies / detectives, and I rate it with 3 bits of entropy.

Latest: The book has been filmed, as revied on Slashdot.

The Last Lieutenant

Corregidor features yet again in this novel about the collapse of the island fortress and the plight of the last remaining coding officer.

Showing more of the Allies side, The Last Lieutenant, portrays a story of espionage against the communications infrastructure of the Americans in the Pacific. A lot of background, a lot of machinery, and an inside view of the messages sent. Little actual cryptography, but worth some 3 bits of entropy.

If you like daring war stories, this one has it all!

A Fire Upon The Deep

I think Vernor Vinge would have to be my favourite science fiction author, just pipping out Stephenson. A Fire Upon The Deep is a tour de force of 90's science fiction.

It actually has very little crypto in it, so it is hard for me to award it more than 3 bits of entropy. The main players ship out of a port with a third part of a one time pad. The other two parts ship via other means - a security precaution.

The one time slice never makes it to its destination, but is used later in a last ditch effort to establish comms with the good guys, whilst being chased by the bad guys across the universe.

This is not a funny book, but Vinge's humour comes through with a single crypto joke which still makes me laugh. To enjoy the joke, you'll have to buy the book.

An Instance of the Fingerpost

Fingerpost is by far the most serious novel I have read in decades. It is the sort of story that one avidly devours as a teenager, searching pages for the most challenging answers to life, maturity and everything. An Instance of the Fingerpost is a huge historic novel sliced into 4 books, each by different writers handing the story from one to the next.

It is a mystery, developed through the eyes of each successive writer, within the turbulent years of the Restoration, 1663 in Oxford.

A lot of the subplot turns around some encrypted letters that allege to reveal the truth behind the mystery. They've ended up in the care of the government's chief cryptographer, the third story teller. Before we get to his story, we have the tales of a medic and a young man-about-town, the adventure of the first blood transfusion, a scurrilous plot to blacken the name of a gentleman, and the inevitable mysterious damsel in distress.

This is a long, complex book. It's also not light entertainment, or, at least it such that it took me many months to make my way through it. If you are looking for serious historical context, this may work for you. And, the cryptography is interesting for its period and context, but the description of early ciphers only rates 2 bits of entropy.

The Enigma

This book is about the machine, and therefore deserves its title.

Written by Michael Barak, The Enigma is the story of a con man who is offered a 'dirty dozen' deal: go to Europe and steal an Enigma, and all charges will be dropped.

It's actually quite readable as a story, but the crypto component is low to non-existant, unless you like reading descriptions of how the Enigma was constructed. For its irrelevance to the search at hand, it only gets one bit of entropy, but read it nonetheless if you come across it (quite difficult as its out of print, I found my copy at Roy's book club).


To read

The Code Book

Simon Singh's The Code Book is a very readable account of the development of cryptography over the ages. It seems to skate over much material, but Singh shows an ability to pick out the salient events in history, and open them up.

Here is an extract entitled The Arab Cryptanalysts. Curiously this story mirrors the evolution of financial cryptography: only after a significant array of other disciplines were brought to bear by the enlightened scholars of the Islamic world, for a wide range of motives and interests, was the invention of frequency analysis discovered and applied to cryptograms. Thus, the monoalphabetic cipher fell, and cryptanalysis was born.

Unsolved and Solved Ciphers

Elonka maintains a list of well-known unsolved codes and ciphers. A couple of the better-known unsolved ancient historical scripts are also thrown in, since they tend to come up during any discussion of unsolved codes.