OPERATIONAL NOTES
The first rule of an output-feedback mode stream cipher, any of them, is that you should never use the same key to encrypt two different messages. Repeat after me: NEVER USE THE SAME KEY TO ENCRYPT TWO DIFFERENT MESSAGES. If you do, you completely break the security of the system. Here’s why: if you have two ciphertext streams, A + K and B + K, and you subtract one from the other, you get (A + K) – (B + K) = A + K – B – K = A – B. That’s two plaintext streams combined with each other, and is very easy to break. Trust me on this one: you might not be able to recover A and B from A – B, but a professional cryptanalyst can. This is vitally important: never use the same key to encrypt two different messages.
Keep your messages short. This algorithm is designed to be used with small messages: a couple of thousand characters. If you have to encrypt a 100,000-word novel, use a computer algorithm. Use shorthand, abbreviations, and slang in your messages. Don’t be chatty.
For maximum security, try to do everything in your head. If the secret police starts breaking down your door, just calmly shuffle the deck. (Don’t throw it up in the air; you’d be surprised how much of the deck ordering is maintained during the game of 52-Pickup.) Remember to shuffle the backup deck, if you have one.
SECURITY ANALYSIS
There’s quite a lot of it, but it’s far too complicated to reproduce here. See http://www.counterpane.com, or write to Counterpane Systems, 1711 North Ave #16, Oak Park, IL 60302.
LEARNING MORE
I recommend my own book, Applied Cryptography (John Wiley & Sons, 1996), as a good place to start. Then read The Codebreakers, by David Kahn (Scribner, 1996). After that, there are several books on computer cryptography, and a few others on manual cryptography. You can subscribe to my free e-mail newsletter at http://www.counterpane.com/
crypto-gram.html or by sending a blank e-mail message to
[email protected] It’s a fun field; good luck.
E-book Extras
Stephensonia/Cryptonomica
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Cryptonomicon Cypher-FAQ
Neal takes on some “frequently anticipated questions” and answers a few that came up after the 1999 publication of Cryptonomicon.
Mother Earth Motherboard
Neal’s epic 1996 Wired story chronicling, among other mighty techno-feats, the laying of the longest wire on earth (i.e., some of the research that contributed to Cryptonomicon).
Press Conference
Neal’s answers to Cryptonomicon-related questions posed by reporters from Salon.com, The Onion, Locus, and other publications.
Editor’s Note
Cryptonomicon Cypher-FAQ
By Neal Stephenson
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Editor’s note: FAQ means here “Frequently Anticipated Questions,” though a few of the answers below do indeed respond to actual questions. This material touches on matters not covered elsewhere in Neal Stephenson’s Press Conference. The text below is a version of Version 19990428 of “Cryptonomicon Cypher-FAQ,” posted by Neal at http://www.well.com/user/neal/ (i.e., as modified for, this, the May 2003 e-book edition of Cryptonomicon).
Purpose of this document
It is likely that Cypherpunks and other persons interested in crypto will feel some curiosity about my novel Cryptonomicon. If so, they will probably find the available information at Cryptonomicon.com [http://www.cryptonomicon.com, as of May 2003], which is aimed mostly at non-specialists, to be annoyingly long on sales pitch and frustratingly short on technical detail. The purpose of this document is to make available the sort of information that is lacking on sites and in PR documents aimed at the general public.
Index
Overview of the project
What is up with the title?
Why the historical characters, and are some of the other characters based on real people?
There’s some material in this novel that’s hardly politically correct.
Did you have a “policy” for handling Cypherpunks in Cryptonomicon?
So are the “Secret Admirers” Cypherpunks?
Is Cryptonomicon technically accurate?
What are the contributions by others to Cryptonomicon?
What is HavenCo?
Why did you call Windows and Mac OS by their true names but use the fictitious name Finux to refer to what is obviously Linux?
What is that symbol on the cover of Cryptonomicon?
What was the substance of your talk at CFP 2000 in Toronto?
Sir Arthur Conan Doyle’s “The Adventure of the Copper Beeches” (excerpt)
It says in your author bio that you were born in Ft. Meade, Maryland, the home of the NSA. What is up with that?
Overview of the project For several years I have been working on a series of novels on the general subject of cryptology. Since cryptology is mathematics, which most people do not consider interesting reading, I have broadened my scope a little bit to include related fields such as Money (e.g., digital currency); War (e.g., the Enigma); and Power (e.g., crypto export controls), which can provide the basis for a more engaging yarn.
The series, when it is finished, will cover a long span of history; the first novel to be published, Cryptonomicon [May 1999], takes place in the twentieth century. It has two timelines — one set during World War II and the other in the present day. Other volumes, set farther in the past or in the future, will follow as soon as I can get them written.
The series will incorporate many characters and stories, tied together by a few common threads. For example, certain family names keep popping up. Crypto, money, and computers seem to find their way into all of the storylines.
The ongoing presence of crypto as an important force in the characters’ lives is symbolized by a fictitious book called the Cryptonomicon which, according to the story, is originally published in the 1600s as a compendium of cryptographic lore. As new generations of cryptologists come and go, they add new information to this original document until it develops into a kind of Talmudic compilation of whatever has been written about crypto in the last few centuries.
What is up with the title? It has been pointed out that the word “Cryptonomicon” bears obvious similarities to “Cyphernomicon,” which is the title of a Cypherpunk FAQ document by Tim May [http://andercheran.aiind.upv.es/toni/cripto/cyphernomicon/cyphernomicon.contents.html, as of May 2003]. This leads to the question: am I committing some form of plagiarism, or rendering homage, or what? The answer, strangely enough, is neither. I was completely unaware of the existence of Tim May’s Cyphernomicon at the time I came up with “Cryptonomicon.”
According to my fictional storyline, the original Cryptonomicon was written by an English scholar with a Classical education (for those of you who are crypto history buffs, it is modeled after John Wilkins’s 1641 book Mercury). Accordingly, I wanted to give it a Latin-sounding title, and “Cryptonomicon” is what I came up with. It is the sort of title that would blend in pretty well with any seventeenth-century English book list. According to all of the library and Web searches I have done since then, the term “Cryptonomicon” has never appeared anywhere else.
Since becoming aware of the existence of Tim May’s “Cyphernomicon” I have been in touch with him about this near-collision in namespace. Of course I am not authorized to speak on his behalf, but having had an exchange of messages with him, I am now going forward with the understanding that he has no problems or complaints.
Why the historical characters, and are some of the other characters based on real people? Cryptonomicon is not a roman à clef — i.e., a novel that is simply a literal depiction of events with the names changed, and that can be decrypted by figuring out direct correspondences between characters in the novel and actual persons. I would never write a book like that. In the World War II storyline I have included some actual historical figures under their own names, such as Alan Turing and Douglas MacArthur, but all of the other characters are simply made up.
The usual way of explaining wh
at novelists do is to say that their characters are composites. But this implies that every single characteristic of a fictional character can be attributed to some actual person somewhere. This is very far from being the case. The “composite” explanation does not do justice to the amount of content that novelists simply invent. Or to put it another way, it gives us too much credit for being hard workers. Making up composite characters would be tremendously labor-intensive. Fabricating stuff whole cloth is much easier.
Since I began writing novels I have had many startling conversations with total strangers who were convinced that I had somehow based fictional characters on them personally. For example, when doing a signing in Oakland I was approached by a somewhat bewildered young man who was half African-American and half Japanese and who had been working as a pizza delivery driver when he had encountered my book Snow Crash, which features a similar character. When he saw that the book had been written several years previously, he understood that it was just a coincidence, but he still found it to be a little eerie.
This kind of thing happens more frequently than one might expect. The characters in Cryptonomicon come from a fictional world very similar to our real one and so many parallels can be observed, but none of them is based on an actual person.
There’s some material in this novel that’s hardly politically correct. The concept of racial sensitivity had not been dreamed up yet in the World War II era, and so the characters see the world, and express themselves, accordingly. To me this seems more constructive than presenting a sugar-coated view of history, and the fact that the single most admirable character in the whole book is Japanese should put to rest suspicions about my motives. However, people who object to, e.g., Huck Finn on the grounds that it contains racial slurs may want to avoid Cryptonomicon.
Did you have a “policy” for handling Cypherpunks in Cryptonomicon? To write a novel about the modern-day crypto world without showing any awareness of the Cypherpunk phenomenon would suggest carelessness or even dishonesty on the part of the author.
However, if I were a Cypherpunk — (And I am not. I read the list sometimes. But the Cypherpunks blend mathematics and politics. I don’t have enough knowledge to talk about the math, and as an artist I consider myself obligated to avoid politics) — I would view this kind of attention as a double-edged sword. Making members of some group into characters in a novel could be interpreted as a way of honoring the group mentioned. On the other hand, anyone who is unhappy with some aspect of how the book is written is likely to construe it as slander. In my view it is best to avoid giving offense or misleading readers.
My expectation is that most Cypherpunks will find this novel unobjectionable. Cypherpunks are sometimes caricatured as an irrational fringe element. By placing modern-day concerns in a larger context — going back at least to World War II — this book might help to explain some of the concerns that motivate many Cypherpunks.
So are the “Secret Admirers” Cypherpunks? Knowledgeable persons will probably perceive similarities between the Cypherpunks and the Secret Admirers; however, intelligent readers should keep in mind that Cryptonomicon is a work of fiction and that the two groups cannot be simply equated.
To put it another way, when reading Cryptonomicon, for Secret Admirers don’t mentally substitute Cypherpunks. Instead, mentally substitute the existence of cryptologically sophisticated persons not affiliated with governments or other traditional power structures and note that the S.A.’s are loosely inspired by the existence of such persons in the real world, but liberally embroidered on and fictionalized by a novelist whose job it is to make stuff up.
It is important to remember that novels are works of art, and like other works of art, get much of their power from indirectness and ambiguity. Consequently, any readers looking for explicit statements about anything are apt to find this work frustrating.
In any case, the Secret Admirers are not a huge part of the novel. They are part of the general backdrop against which the modern-day storyline plays out. The main characters in the modern-day storyline are high-tech entrepreneurs organizing a startup company to build a data haven and issue a digital currency.
Is Cryptonomicon technically accurate? Any novel that addresses technical subjects sooner or later includes some oversimplifications that make knowledgeable readers cringe. I have tried to go about this project competently, and have aimed for a higher level of accuracy than might be found in some other documents. It contains a few long digressions about crypto that have already gotten me lambasted by reviewers.
But (a), it is fiction after all; and (b), I am not perfect; and (c), even if I were there would probably be cases in which it was better to simplify certain topics to avoid alienating normal readers.
What are the contributions by others to Cryptonomicon? One of the noteworthy features of the novel Cryptonomicon is that it contains a new cryptosystem invented by Bruce Schneier, called Solitaire (though in the actual text of the novel it goes by a different name for a while). Bruce has written a technical Appendix giving a full description of Solitaire. Not only that, but Ian Goldberg has written a Perl script that encrypts and decrypts messages using the Solitaire algorithm. The full text of Ian’s Perl script appears in the body of the novel.
As Bruce explains in the Appendix, Solitaire is specifically designed to offer security against high-tech cryptanalysis, but it is implemented on a low-tech system: an ordinary deck of playing cards. In other words, it is intended for use by people who are living under political regimes where the possession of crypto tools (computers, crypto software, etc.) is itself grounds for confiscation, punishment, etc.
What is a new cryptosystem like Solitaire doing in a novel? It is a mutually beneficial relationship. I needed such a system to play a certain role in the book. But by including Bruce’s full description of the algorithm, and Ian’s Perl script, in the actual text of the novel, we can hopefully leverage the wide publicity and distribution of the book to get this cryptosystem out to places it might not otherwise reach.
What is HavenCo? HavenCo is a data haven recently established on Sealand, which is a micronation off the coast of England. I have known one of the principals, Sameer Parekh, for several years, but I have no other relationship to this company. The concept of a data haven has been around in cyberpunk fiction and on Cypherpunk discussion groups for many, many years — certainly long before I used it in Cryptonomicon. It is a misconception to think that the founders of HavenCo derived their inspiration wholly or even partly from my work, because to actually do a thing is different from to write a novel about it. And the fact that one of the principals at HavenCo is named Avi is a coincidence, by the way.
Why did you call Windows and Mac OS by their true names but use the fictitious name Finux to refer to what is obviously Linux? For the same reason that Batman works in Gotham City and not in New York City — I needed some creative leeway. Finux is the principal operating system used by the characters in the book, but it is different in minor ways from Linux, and I did not want to receive complaints from Linux users pointing out errors in my depiction of Linux.
What is that symbol on the cover of Cryptonomicon? It is one of several symbols that were used, long ago, as a kind of shorthand by alchemists, to denote gold. I provided the publisher’s art department with several such symbols and they happened to choose that one, presumably because it looked the coolest.
What was the substance of your talk at the Computers, Freedom & Privacy Conference in Toronto in 2000? I made what I think is a somewhat nuanced and complicated argument about the nature of security. As such it is difficult to summarize. Basically I think that security measures of a purely technological nature, such as guns and crypto, are of real value, but that the great bulk of our security, at least in modern industrialized nations, derives from intangible factors having to do with the social fabric, which are poorly understood by just about everyone.
If that is true, then those who wish to use the Internet as a tool for enhanci
ng security, freedom, and other good things might wish to turn their efforts away from purely technical fixes and try to develop some understanding of just what the social fabric is, how it works, and how the Internet could enhance it. However, this may conflict with the (absolutely reasonable and understandable) desire for privacy.
For a pithy summary of this interesting quandary, check out this passage from Sir Arthur Conan Doyle’s story “The Adventure of the Copper Beeches,” which suggests that at least one person was thinking about the same issues a hundred years ago:
Sir Arthur Conan Doyle’s “The Adventure of the Copper Beeches” (excerpt) Setup: Watson and Holmes are taking the train to visit a lady in distress who lives on an estate outside of the city of Winchester.
It was an ideal spring day, a light blue sky, flecked with little fleecy white clouds drifting across from west to east. The sun was shining very brightly, and yet there was an exhilarating nip in the air, which set an edge to a man’s energy. All over the country-side, away to the rolling hills around Aldershot, the little red and grey roofs of the farm-steadings peeped out from amidst the light green of the new foliage.