and databases. They had to work alone; teaming up resulted in immediate disqualification. Each year’s instructions opened with a single line: This is a problem, not a puzzle; answer accordingly. The challenge followed.
Brian feared entering might annoy his new boss, a rickety NSA lifer named Jeff McNeil. What, Mobile Support isn’t good enough for you? But McNeil encouraged him. “Rite of passage,” he said. “The Coder Olympics. Sponsored by Red Bull.”
Even then, Brian wasn’t sure. Why waste a Saturday?
The entry deadline came two days before the contest. With a few hours still left to decide, he told Kira and Tony about it over breakfast. Nothing classified, just the outlines. Tony shoveled Raisin Bran in his mouth like an escaped prisoner. Kira picked at a clementine, one tiny slice at a time. Having a teenage girl meant never, never talking about food. At the counter, Becks was making coffee. Of course, she’d just bought a three-hundred-dollar brewer despite their financial crisis.
She really should have married some rich guy from law school.
“Sounds cool,” Tony said. “You should do it.”
“Not sure cool is exactly the word,” Kira said. “But yeah.”
“All right, maybe I will.”
Becks grunted. He knew what that grunt meant.
“Doesn’t Tony have a game Saturday?” she said. Without turning around, still fiddling with the Nespresso machine, like she was asking the air.
As if Tony was going to get off the bench for more than the league-required five-minute minimum. “You can take him. He’d like that.” For once you can be the parent who shows up.
“If you think you have a chance, you should do it.” Which we both know you don’t.
At that moment he decided that nothing in the world would keep him from signing up.
* * *
So it was that at midnight Friday, he found himself staring at his computer. No surprise, the challenge looked impossible. It involved a messaging system that an unnamed “Hostile Foreign Entity” used to communicate with its agents through the Internet. The encryption that protected the system was defined as a 1024-bit asymmetric key. A hundred messages were provided, strings of characters and numbers that the NSA had captured.
In theory, a chain of powerful computers working together for months might break the encryption. But Brian had no chance of writing the code necessary to attack the key directly. He had a basic understanding of encryption. He knew how the first cryptographers had developed public keys. He could explain the relative strength of asymmetric and symmetric systems. But he couldn’t pretend to be an expert. Not at an agency that had PhDs who had literally written textbooks on the subject.
Anyway, he was sure that going straight at the problem would get him nowhere. The Tailored Access coders had no doubt tried that approach. Brian needed something else. If he couldn’t decrypt the messages themselves, maybe he could find a pattern in the metadata, the headers and footers that surrounded them. Find a clue that the TAO guys could pursue, evidence he could think creatively.
Not the greatest idea, but it was all he had. Either that or go home, and he wasn’t ready to go home. No way. He could already see the smirk Rebecca would give him.
He popped open a Red Bull and reconsidered the problem. The messages had been presented in apparently random order. He started by sorting them from oldest to newest, looking for a call-response pattern. Maybe they represented a single intelligence controller communicating with many agents at once. But he soon saw the messages had not been sent in any pattern, at least not one he could understand. Assuming the time stamps were accurate, they spanned almost two years.
Assuming… assuming. So much he didn’t know. Like everyone else in the contest, he was operating with only a fraction of the information he would have had if he actually worked for Tailored Access. For example, the agency might have captured a hundred thousand suspicious messages and only provided these. Or these might be the entire data set.
Nor did he have any idea how the NSA had found the messages. They might have come off of the agency’s standard Internet surveillance—which captured more or less all the data that came over the public Internet—and popped up as worth another look. On the other hand, the agency might have targeted a specific network. Or these messages might even have come off the hard drive of a single laptop that soldiers had captured in Afghanistan.
But in that case, Brian would have expected the messages to be roughly