The Pentagon is updating its classified rules for warfare in cyberspace for the first time in seven years. “If the nation’s critical infrastructure came under attack from poisonous code over a computer network from overseas, the first effort would be gathering information on the malware and the systems under attack. Network defenses would be in place, as “our first instinct will be to pull up the drawbridge and prevent the attack, that is to say, block or defend,” according to Gen. Martin E. Dempsey, chairman of the Joint Chiefs of Staff. http://www.nytimes.com/2013/06/28/us/pentagon-is-updating-conflict-rules-in-cyberspace.html?ref=us    The military headquarters responsible for computer-network warfare, the United States Cyber Command, will grow by 4,000 personnel with an additional investment of $23 billion, General Dempsey said. (Cyber Command and the National Security Agency are led by the same officer, Gen. Keith B. Alexander.)