A lack of proactive protection from cyber-attacks on US defence department networks has cost tax payers about $100m in the past six months, US strategic command officials have revealed.
Protecting the networks is a huge challenge for the command, Air Force general Kevin Chilton told a cyber-security conference in Omaha, according to US media reports.
The networks are attacked thousands of times a day, he said, ranging from plain vandalism to theft of money and information.
Chilton said cyber-protection should be more proactive, which will require people working in the defence department to change the way they conduct themselves in cyber-space.
According to Chilton, cyber-security in the defence departments would improve if people just followed the basic rules and procedures that have been put in place.
News of the US military's expenditure on cyber-security comesjust a week after Canadian researcherspublished a report that proves that state-sponsored cyber-espionage is not science fiction, but a real and present threat.
The China-based operation, dubbed GhostNet, infiltrated more than 1,000 computers in more than 100 countries, the researchers found.
The spy operation targeted politicians, diplomats and journalists using spyware installed on computers to gain access to sensitive information since 2007.