Cryptonomicon

He realizes something: The Americans must have done the impossible: broken all of their codes. That explains Midway, it explains the Bismarck Sea, Hollandia, everything. It especially explains why Yamamoto--who ought to be sipping green tea and practicing calligraphy in a misty garden--is, in point of fact, on fire and hurtling through the jungle at a hundred miles per hour in a chair, closely pursued by tons of flaming junk. He must get word out! The codes must all be changed! This is what he is thinking when he flies head-on into a hundred-foot-tall Octomelis sumatrana.

Chapter 40 ANTAEUS

When Lawrence Pritchard Waterhouse sets foot on the Sceptered Isle for the first time in several months, at the ferry terminal in Utter Maurby, he is startled to find allusions to springtime all over the place. The locals have installed flower boxes around the pier, and all of them are abloom with some sort of pre Cambrian decorative cabbage. The effect is not exactly cheerful, but it does give the place a haunted Druidical look, as if Waterhouse is looking at the northwesternmost fringe of some cultural tradition from which a sharp anthropologist might infer the existence of actual trees and meadows several hundred miles farther south. For now, lichens will do--they have gotten into the spirit and turned greyish purple and greyish green.

He and Duffel, their old companionship renewed, tussle their way over to the terminal and fight each other for a seat aboard the disconcertingly quaint two-car Manchester-bound whistle-stop. It will sit there for another couple of hours raising steam before leaving, giving him plenty of time to take stock.

He's been working on some information-theoretical problems occasioned by the Royal and U.S. Navies' recent (14) propensity to litter the floor of the Atlantic with bombed and torpedoed milchcows. These fat German submarines, laden with fuel, food, and ammunition, loiter in the Atlantic Ocean, using radio rarely and staying well away from the sea-lanes, and serve as covert floating supply bases so that the U-boats don't have to go all the way back to the European mainland to refuel and rearm. Sinking lots of 'em is great for the convoys, but must seem conspicuously improbable to the likes of a Rudolf von Hacklheber.

Usually, just for the sake of form, the Allies send out a search plane beforehand to pretend to stumble upon the milchcow. But, setting aside some of their blind spots in the political realm, the Germans are bright chaps, and cannot be expected to fall for that ruse forever. If we are going to keep sending their milchcows to the bottom, we need to come up with a respectable excuse for the fact that we always know exactly where they are!

Waterhouse has been coming up with excuses as fast as he can for most of the late winter and early spring, and frankly he is tired of it. It has to be done by a mathematician if it's to be done correctly, but it's not exactly mathematics. Thank god he had the presence of mind to copy down the crypto worksheets that he discovered in the U-boat's safe, which give him something to live for.

In a sense he is wasting his time; the originals have long since gone off to Bletchley Park where they were probably deciphered within hours. But he's not doing it for the war effort per se, just trying to keep his mind sharp and maybe add a few leaves to the next edition of the Cryptonomicon.When he arrives at Bletchley, which is his destination of the moment, he will have to ask around and find out what those messages actually said.

Usually, he is above such cheating. But the messages from U-553 have him completely baffled. They were not produced on an Enigma machine, but they are at least that difficult to decrypt. He does not even know, yet, what kind of cipher he is dealing with. Normally, one begins by figuring out, based on certain patterns in the ciphertext, whether it is, for example, a substitution or a transposition system, and then further classifying it into, say, an aperiodic transposition cipher in which keying units of constant length encipher plaintext groups of variable length, or vice versa. Once you have classified the algorithm, you know how to go about breaking the code.

Waterhouse hasn't even gotten that far. He now strongly suspects that the messages were produced using a one-time pad. If so, not even Bletchley Park will be able to break them, unless they have somehow obtained a copy of the pad. He is half-hoping that they will tell him that this is the case so that he can stop ramming his head against this particular stone wall.

In a way, this would raise even more questions than it would answer. The Triton four-wheel naval Enigma was supposedly considered by the Germans to be perfectly impregnable to cryptanalysis. If that was the case, then why was the skipper of U-553 employing his own private system for certain messages?