Digital Fortress

Digital Fortress Page 30

Still unnerved from her encounter with Hale, Susan gazed out through the one-way glass of Node 3. The Crypto floor was empty. Hale was silent again, engrossed. She wished he would leave.

She wondered if she should call Strathmore; the commander could simply kick Hale out-after all, it was Saturday. Susan knew, however, that if Hale got kicked out, he would immediately become suspicious. Once dismissed, he probably would start calling other cryptographers asking what they thought was going on. Susan decided it was better just to let Hale be. He would leave on his own soon enough.

An unbreakable algorithm. She sighed, her thoughts returning to Digital Fortress. It amazed her that an algorithm like that could really be created-then again, the proof was right there in front of her; TRANSLTR appeared useless against it.

Susan thought of Strathmore, nobly bearing the weight of this ordeal on his shoulders, doing what was necessary, staying cool in the face of disaster.

Susan sometimes saw David in Strathmore. They had many of the same qualities-tenacity, dedication, intelligence. Sometimes Susan thought Strathmore would be lost without her; the purity of her love for cryptography seemed to be an emotional lifeline to Strathmore, lifting him from the sea of churning politics and reminding him of his early days as a code-breaker.

Susan relied on Strathmore too; he was her shelter in a world of power-hungry men, nurturing her career, protecting her, and, as he often joked, making all her dreams come true. There was some truth to that, she thought. As unintentional as it may have been, the commander was the one who'd made the call that brought David Becker to the NSA that fateful afternoon. Her mind reeled back to him, and her eyes fell instinctively to the pull-slide beside her keyboard. There was a small fax taped there.

The fax had been there for seven months. It was the only code Susan Fletcher had yet to break. It was from David. She read it for the five-hundredth time.

PLEASE ACCEPT THIS HUMBLE FAX

MY LOVE FOR YOU IS WITHOUT WAX.

He'd sent it to her after a minor tiff. She'd begged him for months to tell her what it meant, but he had refused. Without wax. It was David's revenge. Susan had taught David a lot about code-breaking, and to keep him on his toes, she had 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.