The Zero Hour (10 page)

In many areas of the world, topographical concerns—mountains, bodies of water, and the like—make it impossible for telephone conversations to travel exclusively by landlines. So an enormous volume of telephone traffic is beamed between microwave towers. Because each microwave tower sends out its transmission in the shape of a cone, some of the waves continue to travel into the ether, where they can be picked up by satellite.

The captured signal, which contained a fragment of the telephone conversation, was scooped up by a hovering NSA Rhyolite satellite and relayed to another satellite over Australia, thence to a relay site, and then to Fort Meade, where some twenty-seven acres of computers are located deep below the National Security Agency’s Headquarters/Operations Building. It is said to be the most formidable concentration of computational power in the world.

Within minutes, the signal was classified and reconstructed. Only then were a couple of interesting things learned about the captured telephone conversation.

First, the NSA analysts discovered that the signal was digital: it had been converted into a series of zeroes and ones. Digital signals have a great advantage over analog signals in that they are received with maximum clarity.

Digital signals have another advantage over analog. Once scrambled, they are secure, impenetrable, impossible to be understood by anyone outside a handful of government agencies in the most developed countries.

Then the NSA analysts discovered a second interesting thing. The captured conversation had been rendered even more secure from eavesdropping by means of a state-of-the-art digital encryption system. It is not uncommon these days for private citizens—particularly in the world of high finance—to make their most sensitive calls on sophisticated, secure telephones that digitally encrypt their voices so that they can’t be bugged, tapped, or otherwise eavesdropped on.

But the vast majority of suppliers of these secure phones (one of the biggest is Crypto A.G. of Zurich) cooperate with law enforcement by selling their encryption schemes to both the National Security Agency and the British GCHQ (the Government Communications Headquarters, in Cheltenham, England, which is the British counterpart of the NSA). So even most encrypted phone conversations can be listened to by the NSA and GCHQ. International businessmen discussing illegal schemes and drug cartels discussing transactions all tend to speak carelessly over “secure” phones, not realizing that most of them really aren’t secure at all.

But this particular digitally encrypted format was unknown to either NSA or GCHQ. And that was the third peculiar discovery.

The scrambled signal was sent immediately to the Cryptanalytic Division at NSA’s Headquarters/Operations Building. There it was run through a Cray supercomputer, which tested the signal against all known encryption schemes. But the Cray came up blank. The signal wouldn’t break. Instead of voices speaking, there was only a bewildering sequence of ones and zeroes that the computer couldn’t comprehend.

This in itself was extraordinary. The NSA’s computers are programmed with the keys to virtually every known cipher ever invented, every mechanism to encipher that has ever been used. This includes any system ever used by anyone at any time in history, anything ever written about in a technical paper, in a book, even in a novel, any cipher that’s ever been even floated as a hypothesis.

As long as the computers are fed a large enough sample of the cipher, and the encryption scheme is known to the NSA, they will crack the code. Most digital signals are broken immediately. But after minutes, then hours of churning, the computers were stumped.

The NSA abhors the existence of any encryption scheme it doesn’t know. To a cryptanalyst, an “unbreakable” encryption is like an impenetrable safe to a master safecracker, an unpickable lock to a master lockpick. It is a challenge, a taunt, a red flag.

Two cryptanalysts—cryppies, as they’re called within the Fort Meade complex—hunched before a screen and watched with mingled fascination and frustration.

“Jeez, what’s wrong with this one?” George Frechette said to his officemate, Edwin Chu. “Everything’s processing except this one string. Now what?”

Edwin Chu adjusted his round horn-rimmed glasses and peered through them for several moments at the flashing numbers on the screen. “We got us a new one.”

“What do you say we have a look at it?” George suggested. “Play with it a little?”

“Sure,” Edwin said. “Hey, I’m there.”

CHAPTER FOURTEEN

Professor Bruce Gelman, a small, slender, balding man with a wispy beard, was an assistant professor of computer science at MIT with a national reputation in the field of electronic engineering. According to Ken Alton, he was also a legendary hacker skilled in the intricacies of telephony and one of the founders of the Thinking Machines Corporation.

He could have been in his thirties or forties; it was impossible to tell. Dressed in a woolen lumberjack shirt over a plaid flannel shirt, he did not look like a typical university professor, but then, computer types rarely did. His office was located in the Artificial Intelligence Laboratory in a tall, anonymous office building in Kendall Square, Cambridge.

“I thought you guys were up to speed on this stuff,” he said, sipping coffee from a giant plastic cup. “You’re telling me the FBI labs threw in the towel?”

“Basically, yes,” Sarah said.

Gelman rolled his eyes, scratched at his beard, and chuckled. “
I
see,” he said with exaggerated politeness, leaving no doubt what he thought of the FBI. “Of course, this technician you talked to is right: it’s not exactly
easy
to restore a tape that’s been erased. That’s true.”

She removed from her briefcase a black cassette sealed in a plastic evidence bag and marked with a number, took it out of the bag, and handed it to him.

He gulped some more coffee, set down the cup, and knitted his brow. “We could get lucky,” he said. “Might be an old answering machine. Or just a poorly constructed one.”

“Why would that help?”

“Maybe the tape wobbles up and down in the machine, relative to the heads. Possible the tape guides are loose, and the tape wandered up and down some.”

“That would make it easier?”

He shot his left hand out for the enormous cup of coffee, and accidentally tipped it over. “Oh, God. Yuck.” Pulling some sheets of pale-blue Kleenex from a plastic dispenser, he mopped up the muddy spill, which coursed over a stack of papers. “Yuck.”

He retrieved the enormous cup, managing to salvage half the coffee. “You see, that would leave us a stripe of recorded information above or below what’s been recorded over it.”

“And if the answering machine isn’t old, or the tape guides aren’t loose?”

“Well,” Gelman said, “tape is three-dimensional, right?” He slurped loudly from the coffee cup, then gingerly set it down. “It has a thickness to it. The front and the back surfaces of the tape are affected differently by the recording process.”

Sarah didn’t entirely understand what he was driving at, but nodded anyway.

“So you compare the front and back surfaces of the tape,” he went on, “to see if there are any traces of magnetic information on the
back
of the tape. Sometimes that works.”

“And if not?”

“Well, then there’s an effect called ‘print-through,’ where you find traces on
one
section of the tape of what’s been recorded on a section right
next
to it. So there are various places to look for data. I’m surprised your labs didn’t think of this.” He shook his head disapprovingly. “So we can scan the tape and reconstruct it two-dimensionally, using VCR technology.”

“Can you explain that?”

He frowned and looked down at the coffee-stained papers arrayed on the desk before him. “So, it’s like this,” Gelman said. “This is a technique I developed for a—another government agency, under contract. Oh, hell, it’s obviously the NSA. Anyways, normally an audio tape is magnetized, negative or positive, on a stripe, okay?”

Sarah nodded.

“But on a
videotape
, the information is laid down differently. It’s recorded on stripes put down at a transverse angle to the tape, in order to fit more information on the same length of tape.”

“Uh huh.”

“So when it comes time to play back, a VCR uses a helical-scan playback head to read that information. Meaning the tape head moves at sort of an angle across the tape, okay?”

“Okay.”

“So if you want to play back a really narrow stripe of leftover information that’s sort of on the
edges
of a broader band—the vertical information as well as the horizontal—you can use this VCR technology, a similar helical-scan playback device.”

He paused a moment, and Sarah nodded to encourage him to proceed.

“So the helical scan goes across the tape, transversely, moving up through the
newly
recorded stuff and then over the narrow band of leftover information—the stuff we’re interested in, right? So, at regular intervals, we have these little blips of the stuff we want. The rest is garbage.” Gelman spoke more and more rapidly, with growing enthusiasm. “So, then the question is, how do you sort the wheat from the chaff, you know what I mean? How do you separate out the sound you want from the sound you don’t? Well, what you do is, you write a program to differentiate it out, right?”

“Right.”

“Now, I know the distance and the time between the bits of the stripe we’re interested in—the sequence of magnetic impulses, let’s call it. I can calculate it on the basis of the rate at which the playback head is revolving. I know the
periodicity.
So, I tell the computer what I’m looking for and to pull out any signals of interest. Then we put sort of a digital ‘picture’ of the magnetic information onto a computer, using a specially constructed piece of equipment, a helical-scan tape playback mechanism that converts the analog signal to a digital signal. It’s the same technology as a compact-disc player or a digital audio tape, right? Really, it’s a modified digital compact cassette playback unit that can play back the recovered audio tape as if it were high-density digital tape.”

“Look,” Sarah broke in at last. “Computer stuff is obviously not my area of expertise, which is why I’m talking to you. You’re saying you may be able to unerase this tape, right?”

“That’s right.”

“How long would it take you?”

“The process might take a few hours, maybe. But to do it right, a week, probably—”

“Okay. I’d like to hire your services on a contract basis. Could you have something for me in two or three days?”

“Three days?”
Gelman gasped. “I mean, theoretically, yes, but—”

“That would be great,” Sarah said. “Thanks.”

CHAPTER FIFTEEN

Baumann awoke with a pounding headache, covered in a cold sweat. The linen bedsheet around him was soaked, as if he’d been doused with gallons of cold water. He drew back the heavy drapes to let in the strong morning sunlight. Looking down at the Avenue des Portugais, then up at the sky, he estimated that it was eight or nine o’clock. He had badly needed the sleep, but there was much to be done today.

For a few moments he sat on the edge of the bed and massaged his temples to ease the headache. His head spun with the residue of nightmares. He had dreamed he was back in the hole, that black chamber of horrors.

He had abided the floggings, the “cuts” with a cane while you were strapped, spread-eagled, to the three-legged mare, a prison physician standing dourly by. But the hole, or the “bomb,” as some called it, was the worst place in Pollsmoor, a dank horrific place it had taken all of his strength to endure without cracking. The hole was where they put you to punish you for fighting in the exercise yard, for striking a
boer
, for no reason at all other than that the chief warder didn’t like your face. Actually, he had spent no more than a month there in all his years at Pollsmoor. It meant solitary confinement, a bare concrete cell, a “punishment regime” of maize porridge and watery broth and more porridge.

No cigarettes, no newspapers, no letters, no visitors. No radio, no television. No contact with the outside world; no leaving the tiny, fetid, unlighted cell, whose walls began to close in on you. You lived like an animal in a cage rank with your own urine and excrement from the shallow hole in the ground into which you had to relieve yourself.

Why was he having this dream again? What did it mean? That his subconscious didn’t believe he was out of prison? That his mind understood things on a higher plane: he was still not out of prison?

He took a long, almost unbearably hot shower. Then he got into one of the hotel’s thick white cotton robes (“Hôtel Raphaël Paris” stitched in gold on the breast), settled into one of the suite’s chaises longues, and began to make telephone calls. As he spoke—his French, slightly British-accented, was impeccable—he idly combed his damp hair straight back.

*   *   *

He’d flown into Orly from Geneva’s Cointrin Airport, on a false passport provided by Dyson’s staff. Travel within the European Economic Community had become remarkably casual since he’d been locked away. No one gave his Swiss passport so much as a passing glance. But however Dyson’s people had procured the passport, he didn’t trust it. If it was forged, was the forgery top-notch? Was the forger an informer for the Swiss authorities? If it was a legitimate passport, what if it had been flagged as missing? If someone in the Swiss government had been paid off, how secure was that transaction?

Dyson had offered to supply a full set of the documents he’d need—passports, driver’s licenses, credit cards—but he’d politely turned down the offer. Dyson-supplied paper was a sheep’s bell: if he chose, Dyson could keep close tabs on his whereabouts.

Until he made contact with a professional forger, he needed to create a plausible identity from scratch. Things had gotten more complicated in the last five or six years. Passports were more difficult to forge; you could no longer rent a car with cash. The emergence of worldwide terrorism had spurred the airlines to impose random security checks of checked and carry-on baggage on transatlantic flights. It was a much more suspicious world. Also, he didn’t dare acquire all of his documentation in one place, from one source. He would have to travel to a number of countries in the next few days.