There's a growing awareness in the U.S. Defense Department that wars can be won or lost online - and we don't mean wars of the role-playing kind. Currently, only 80 students are graduated annually from the Pentagon's "cyberwar" schools, a number Defense Secretary Robert Gates wants to quadruple in two years.  Already, the service academies - like the Army's West Point and the Navy's Annapolis - stage exercises where computer science and information technology majors must fend off harrowing attacks from the National Security Agency. These aren't just academic exercises, say Corey Kilgannon and Noam Cohen in the New York Times:

When the military deploys in a combat zone or during a domestic emergency, establishing a secure Internet connection is an early priority. To keep things humming, the military's experts must fend off the ordinary chaos of the Internet as well as attacks devised to disable the communications system, like flooding e-mail servers with so many junk messages that they collapse.

One tool of choice: Linux. West Point's team likes it because:

"'s very cheap and very customizable," Cadet (Brian) McCord said. It is also much easier to secure because "you can tweak it for everything you need" and there are not as many known ways to attack it, he said.

-- Mark Feffer