A team of Army cadets spent four days at West Point last week struggling around the clock to keep a computer network operating while hackers from the National Security Agency tried to infiltrate it with methods that an enemy might use. The NSA made the cadets' task more difficult by planting viruses on some of the equipment, just as real-world hackers have done on millions of computers around the world. The competition was a final exam for computer science and information technology majors, who competed against teams from the Navy, Air Force, Coast Guard and Merchant Marine as well as the Naval Postgraduate Academy and the Air Force Institute of Technology. Ideally, the teams would be allowed to attack other schools' networks while also defending their own but only the NSA, with its arsenal of waivers, loopholes, special authorizations is allowed to take down a US network. NSA tailored its attacks to be just 'a little too hard for the strongest undergraduate team to deal with, so that we could distinguish the strongest teams from the weaker ones.' The winning West Point team used Linux, instead of relying on proprietary products from big-name companies like Microsoft or Sun Microsystems."