CIA headquarters in Langley, Virginia

For those senior IT managers who are the "privileged users," meaning system administrators, "there is certainly more scrutiny on you," Tarasiuk says. "It's interesting: there's so much scrutiny that a normal person might not want to put up with that. But it's part of the mission."

There's so much top secret information contained within the CIA's systems that IT plays a key infosecurity role in making sure that CIA employees are not doing anything nefarious. There's also the persistent threat of foreign government intelligence agencies trying to break into the CIA's networks and databases. "We have a counterintelligence center that helps us with that," Tarasiuk says. "They are very concerned about foreign intelligence services that are interested in penetrating the CIA. Because of that we pay particular attention to the kinds of things we put on our network."

The CIA's networks aren't directly connected to the Internet. "We have a very closed network that's connected to an intelligence community enterprise," Tarasiuk says, "so I don't necessarily have the worries about the hackers from the Internet trying to break through."

What he does have to be concerned with is those who are allowed on the CIA's networks: whether it's a simple computing oversight by a CIA analyst or a disgruntled spy intent on selling top secret intel to Chinese government officials. "Anyone who logs into any one of our systems knows they are being audited, and we look for anomalies," he says. "We always have some worries about a rogue person on a network doing this. But we can catch them."

So you have caught people? "We catch people getting into places they shouldn't go, from time to time," Tarasiuk responds.

When asked about the fact that human beings are typically the weakest link in any IT system, Tarasiuk concurs. "Nothing's perfect. The system's not perfect," he says. "Some of [the infosec alerts] might be legitimate results of why they are doing it; some might be false positives. But for the most part we feel very strongly that we can detect when someone is doing something of a malicious nature."

See Part 1 (8/4/08): A business-IT alignment project like few others

See Part 2 (8/5/08): How IT moved to center stage at the CIA in the wake of 9/11

See Part 3 (8/6/08): The CIA's CIO navigates a tense line between making data visible and keeping secrets

See Part 4 (8/7/08): The CIA's efforts to use new applications and Web 2.0 technologies

Also see: "What It's Like to Work Overseas for the CIA's IT Group"