Washington: A top National Security Agency (NSA) hacker has revealed some new secrets about the way hacking is done by the American agency.

The NSA has come under the scanner in the last couple of years over its controversial surveillance policies and the agency recently revealed how some of its best hackers operate. ABC News reported that some of the world's best computer hackers are employed by the NSA to break into networks around the globe.

The Tailored Access Operations cell (TAO) functions under secretive terms, but the NSA chief has revealed some truly amazing secrets about the operation of the top hackers.

"I will admit that it's very strange, to be in that position and up her on a stage in front of a group of people," said Rob Joyce, the head of the NSA's TAO. Joyce was speaking to an audience at the Usenix Enigma security conference held in San Francisco this Wednesday.

"I'm in a unique position in that we produce, in TAO, foreign intelligence for a wide range of missions to include advice for informing policymakers, protecting the nation's warfighters 24/7 and in that space we're doing nation-state exploitation. My talk today is to tell you, as a nation-state exploiter, what you can do to defend yourself, to make my life hard."

Joyce went to explain how to make it difficult for the NSA to keep tabs on people, and the steps taken by TAO when they have a target in sight. According to Joyce, six steps are needed to taking down a hacker: reconnaissance, initial exploitation, persistence, tool installation, lateral movement, and collection and analysis of data.