Digital Fortress

by Dan Brown

  taken to encoding all of her messages to him with some simple encryption scheme. Shopping lists, love notes-they were all encrypted. It was a game, and David had become quite a good cryptographer. Then he'd decided to return the favor. He'd started signing all his letters "Without wax, David." Susan had over two dozen notes from David. They were all signed the same way. Without wax.

  Susan begged to know the hidden meaning, but David wasn't talking. Whenever she asked, he simply smiled and said, "You're the code-breaker."

  The NSA's head cryptographer had tried everything-substitutions, cipher boxes, even anagrams. She'd run the letters "without wax" through her computer and asked for rearrangements of the letters into new phrases. All she'd gotten back was: taxi hut wow. It appeared Ensei Tankado was not the only one who could write unbreakable codes.

  Her thoughts were interrupted by the sound of the pneumatic doors hissing open. Strathmore strode in.

  "Susan, any word yet?" Strathmore saw Greg Hale and stopped short. "Well, good evening, Mr. Hale." He frowned, his eyes narrowing. "On a Saturday, no less. To what do we owe the honor?"

  Hale smiled innocently. "Just making sure I pull my weight."

  "I see." Strathmore grunted, apparently weighing his options. After a moment, it seemed he too decided not to rock Hale's boat. He turned coolly to Susan. "Ms. Fletcher, could I speak to you for a moment? Outside?"

  Susan hesitated. "Ah… yes, sir." She shot an uneasy glance at her monitor and then across the room at Greg Hale. "Just a minute."

  With a few quick keystrokes, she pulled up a program called ScreenLock. It was a privacy utility. Every terminal in Node 3 was equipped with it. Because the terminals stayed on around the clock, ScreenLock enabled cryptographers to leave their stations and know that nobody would tamper with their files. Susan entered her five-character privacy code, and her screen went black. It would remain that way until she returned and typed the proper sequence.

  Then she slipped on her shoes and followed the commander out.

  * * *

  "What the hell is he doing here?" Strathmore demanded as soon as he and Susan were outside Node 3.

  "His usual," Susan replied. "Nothing."

  Strathmore looked concerned. "Has he said anything about TRANSLTR?"

  "No. But if he accesses the Run-Monitor and sees it registering seventeen hours, he'll have something to say all right."

  Strathmore considered it. "There's no reason he'd access it."

  Susan eyed the commander. "You want to send him home?"

  "No. We'll let him be." Strathmore glanced over at the Sys-Sec office. "Has Chartrukian left yet?"

  "I don't know. I haven't seen him."

  "Jesus." Strathmore groaned. "This is a circus." He ran a hand across the beard stubble that had darkened his face over the past thirty-six hours. "Any word yet on the tracer? I feel like I'm sitting on my hands up there."

  "Not yet. Any word from David?"

  Strathmore shook his head. "I asked him not to call me until he has the ring."

  Susan looked surprised. "Why not? What if he needs help?"

  Strathmore shrugged. "I can't help him from here-he's on his own. Besides, I'd rather not talk on unsecured lines just in case someone's listening."

  Susan's eyes widened in concern. "What's that supposed to mean?"

  Strathmore immediately looked apologetic. He gave her a reassuring smile. "David's fine. I'm just being careful."

  * * *

  Thirty feet away from their conversation, hidden behind the one-way glass of Node 3, Greg Hale stood at Susan's terminal. Her screen was black. Hale glanced out at the commander and Susan. Then he reached for his wallet. He extracted a small index card and read it.

  Double-checking that Strathmore and Susan were still talking, Hale carefully typed five keystrokes on Susan's keyboard. A second later her monitor sprang to life.

  "Bingo." He chuckled.

  Stealing the Node 3 privacy codes had been simple. In Node 3, every terminal had an identical detachable keyboard. Hale had simply taken his keyboard home one night and installed a chip that kept a record of every keystroke made on it. Then he had come in early, swapped his modified keyboard for someone else's, and waited. At the end of the day, he switched back and viewed the data recorded by the chip. Even though there were millions of keystrokes to sort through, finding the access code was simple; the first thing a cryptographer did every morning was type the privacy code that unlocked his terminal. This, of course, made Hale's job effortless-the privacy code always appeared as the first five characters on the list.

  It was ironic, Hale thought as he gazed at Susan's monitor. He'd stolen the privacy codes just for kicks. He was happy now he'd done it; the program on Susan's screen looked significant.

  Hale puzzled over it for a moment. It was written in LIMBO-not one of his specialties. Just by looking at it, though, Hale could tell one thing for certain-this was not a diagnostic. He could make sense of only two words. But they were enough.

  TRACER SEARCHING…

  "Tracer?" he said aloud. "Searching for what?" Hale felt suddenly uneasy. He sat a moment studying Susan's screen. Then he made his decision.

  Hale understood enough about the LIMBO programming language to know that it borrowed heavily from two other languages-C and Pascal-both of which he knew cold. Glancing up to check that Strathmore and Susan were still talking outside, Hale improvised. He entered a few modified Pascal commands and hit return. The tracer's status window responded exactly as he had hoped.

  TRACER ABORT?

  He quickly typed: YES

  ARE YOU SURE?

  Again he typed: YES

  After a moment the computer beeped.

  TRACER ABORTED

  Hale smiled. The terminal had just sent a message telling Susan's tracer to self-destruct prematurely. Whatever she was looking for would have to wait.

  Mindful to leave no evidence, Hale expertly navigated his way into her system activity log and deleted all the commands he'd just typed. Then he reentered Susan's privacy code.

  The monitor went black.

  When Susan Fletcher returned to Node 3, Greg Hale was seated quietly at his terminal.

  Chapter 30

  Alfonso XIII was a small four-star hotel set back from the Puerta de Jerez and surrounded by a thick wrought-iron fence and lilacs. David made his way up the marble stairs. As he reached for the door, it magically opened, and a bellhop ushered him inside.

  "Baggage, senor? May I help you?"

  "No, thanks. I need to see the concierge."

  The bellhop looked hurt, as if something in their two-second encounter had not been satisfactory. "Por aqui, senor." He led Becker into the lobby, pointed to the concierge, and hurried off.

  The lobby was exquisite, small and elegantly appointed. Spain's Golden Age had long since passed, but for a while in the mid-1600s, this small nation had ruled the world. The room was a proud reminder of that era-suits of armor, military etchings, and a display case of gold ingots from the New World.

  Hovering behind the counter marked conserje was a trim, well-groomed man smiling so eagerly that it appeared he'd waited his entire life to be of assistance. "En que puedo servirle, senor? How may I serve you?" He spoke with an affected lisp and ran his eyes up and down Becker's body.

  Becker responded in Spanish. "I need to speak to Manuel."

  The man's well-tanned face smiled even wider. "Si, si, senor. I am Manuel. What is it you desire?"

  "Senor Roldan at Escortes Belen told me you would-"

  The concierge silenced Becker with a wave and glanced nervously around the lobby. "Why don't you step over here?" He led Becker to the end of the counter. "Now," he continued, practically in a whisper. "How may I help you?"

  Becker began again, lowering his voice. "I need to speak to one of his escorts whom I believe is dining here. Her name is Rocio."

  The concierge let out his breath as though overwhelmed. "Aaah, Rocio-a beautiful creature."


  "I need to see her immediately."

  "But, senor, she is with a client."

  Becker nodded apologetically. "It's important." A matter of national security.

  The concierge shook his head. "Impossible. Perhaps if you left a-"

  "It will only take a moment. Is she in the dining room?"

  The concierge shook his head. "Our dining room closed half an hour ago. I'm afraid Rocio and her guest have retired for the evening. If you'd like to leave me a message, I can give it to her in the morning." He motioned to the bank of numbered message boxes behind him.

  "If I could just call her room and-"

  "I'm sorry," the concierge said, his politeness evaporating. "The Alfonso XIII has strict policies regarding client privacy."

  Becker had no intention of waiting ten hours for a fat man and a prostitute to wander down for breakfast.

  "I understand," Becker said. "Sorry to bother you." He turned and walked back into the lobby. He strode directly to a cherry roll-top desk that had caught his eye on his way in. It held a generous supply of Alfonso XIII postcards and stationery as well as pens and envelopes. Becker sealed a blank piece of paper in an envelope and wrote one word on the envelope.

  ROCIO.

  Then he went back to the concierge.

  "I'm sorry to trouble you again," Becker said approaching sheepishly. "I'm being a bit of a fool, I know. I was hoping to tell Rocio personally how much I enjoyed our time together the other day. But I'm leaving town tonight. Perhaps I'll just leave her a note after all." Becker laid the envelope on the counter.

  The concierge looked down at the envelope and clucked sadly to himself. Another lovesick heterosexual, he thought. What a waste. He looked up and smiled. "But of course, Mr….?"

  "Buisan," Becker said. "Miguel Buisan."

  "Of course. I'll be sure Rocio gets this in the morning."

  "Thank you." Becker smiled and turned to go.

  The concierge, after discreetly checking out Becker's backside, scooped up the envelope off the counter and turned to the bank of numbered slots on the wall behind him. Just as the man slipped the envelope into one of the slots, Becker spun with one final inquiry.

  "Where might I call a taxi?"

  The concierge turned from the wall of cubbyholes and answered. But Becker did not hear his response. The timing had been perfect. The concierge's hand was just emerging from a box marked Suite 301.

  Becker thanked the concierge and slowly wandered off looking for the elevator.

  In and out, he repeated to himself.

  Chapter 31

  Susan returned to Node 3. Her conversation with Strathmore had made her increasingly anxious about David's safety. Her imagination was running wild.

  "So," Hale spouted from his terminal. "What did Strathmore want? A romantic evening alone with his head cryptographer?"

  Susan ignored the comment and settled in at her terminal. She typed her privacy code and the screen came to life. The tracer program came into view; it still had not returned any information on North Dakota.

  Damn, Susan thought. What's taking so long?

  "You seem uptight," Hale said innocently. "Having trouble with your diagnostic?"

  "Nothing serious," she replied. But Susan wasn't so sure. The tracer was overdue. She wondered if maybe she'd made a mistake while writing it. She began scanning the long lines of LIMBO programming on her screen, searching for anything that could be holding things up.

  Hale observed her smugly. "Hey, I meant to ask you," he ventured. "What do you make of that unbreakable algorithm Ensei Tankado said he was writing?"

  Susan's stomach did a flip. She looked up. "Unbreakable algorithm?" She caught herself. "Oh, yeah… I think I read something about that."

  "Pretty incredible claim."

  "Yeah," Susan replied, wondering why Hale had suddenly brought it up. "I don't buy it, though. Everyone knows an unbreakable algorithm is a mathematical impossibility."

  Hale smiled. "Oh, yeah… the Bergofsky Principle."

  "And common sense," she snapped.

  "Who knows…" Hale sighed dramatically. "There are more things in heaven and earth than are dreamt of in your philosophy."

  "I beg your pardon?"

  "Shakespeare," Hale offered. "Hamlet."

  "Read a lot while you were in jail?"

  Hale chuckled. "Seriously, Susan, did you ever think that maybe it is possible, that maybe Tankado really did write an unbreakable algorithm?"

  This conversation was making Susan uneasy. "Well, we couldn't do it."

  "Maybe Tankado's better than we are."

  "Maybe." Susan shrugged, feigning disinterest.

  "We corresponded for a while," Hale offered casually. "Tankado and me. Did you know that?"

  Susan looked up, attempting to hide her shock. "Really?"

  "Yeah. After I uncovered the Skipjack algorithm, he wrote me-said we were brothers in the global fight for digital privacy."

  Susan could barely contain her disbelief. Hale knows Tankado personally! She did her best to look uninterested.

  Hale went on. "He congratulated me for proving that Skipjack had a back door-called it a coup for privacy rights of civilians all over the world. You gotta admit, Susan, the backdoor in Skipjack was an underhanded play. Reading the world's E-mail? If you ask me, Strathmore deserved to get caught."

  "Greg," Susan snapped, fighting her anger, "that back door was so the NSA could decode E-mail that threatened this nation's security."

  "Oh, really?" Hale sighed innocently. "And snooping the average citizen was just a lucky by-product?"

  "We don't snoop average citizens, and you know it. The FBI can tap telephones, but that doesn't mean they listen to every call that's ever made."

  "If they had the manpower, they would."

  Susan ignored the remark. "Governments should have the right to gather information that threatens the common good."

  "Jesus Christ"-Hale sighed-"you sound like you've been brainwashed by Strathmore. You know damn well the FBI can't listen in whenever they want-they've got to get a warrant. A spiked encryption standard would mean the NSA could listen in to anyone, anytime, anywhere."

  "You're right-as we should be able to!" Susan's voice was suddenly harsh. "If you hadn't uncovered the back door in Skipjack, we'd have access to every code we need to break, instead of just what TRANSLTR can handle."

  "If I hadn't found the back door," Hale argued, "someone else would have. I saved your asses by uncovering it when I did. Can you imagine the fallout if Skipjack had been in circulation when the news broke?"

  "Either way," Susan shot back, "now we've got a paranoid EFF who think we put back doors in all our algorithms."

  Hale asked smugly, "Well, don't we?"

  Susan eyed him coldly.

  "Hey," he said, backing off, "the point is moot now anyway. You built TRANSLTR. You've got your instant information source. You can read what you want, when you want-no questions asked. You win."

  "Don't you mean we win? Last I heard, you worked for the NSA."

  "Not for long," Hale chirped.

  "Don't make promises."

  "I'm serious. Someday I'm getting out of here."

  "I'll be crushed."

  In that moment, Susan found herself wanting to curse Hale for everything that wasn't going right. She wanted to curse him for Digital Fortress, for her troubles with David, for the fact that she wasn't in the Smokys-but none of it was his fault. Hale's only fault was that he was obnoxious. Susan needed to be the bigger person. It was her responsibility as head cryptographer to keep the peace, to educate. Hale was young and naive.

  Susan looked over at him. It was frustrating, she thought, that Hale had the talent to be an asset in Crypto, but he still hadn't grasped the importance of what the NSA did.

  "Greg," Susan said, her voice quiet and controlled, "I'm under a lot of pressure today. I just get upset when you talk about the NSA like we're some kind of high-tech peeping Tom. This organization was founded
for one purpose-to protect the security of this nation. That may involve shaking a few trees and looking for the bad apples from time to time. I think most citizens would gladly sacrifice some privacy to know that the bad guys can't maneuver unchecked."

  Hale said nothing.

  "Sooner or later," Susan argued, "the people of this nation need to put their trust somewhere. There's a lot of good out there-but there's also a lot of bad mixed in. Someone has to have access to all of it and separate the right from wrong. That's our job. That's our duty. Whether we like it or not, there is a frail gate separating democracy from anarchy. The NSA guards that gate."

  Hale nodded thoughtfully. "Quis custodiet ipsos custodes?"

  Susan looked puzzled.

  "It's Latin," Hale said. "From Satires of Juvenal. It means 'Who will guard the guards?' "

  "I don't get it," Susan said. " 'Who will guard the guards?' "

  "Yeah. If we're the guards of society, then who will watch us and make sure that we're not dangerous?"

  Susan nodded, unsure how to respond.