Appropriate measures are being taken to ensure cyber security in armed forces, Defence Minister Manohar Parrikar Tuesday told parliament."Appropriate measures have been taken for ensuring cyber security in armed forces in the form of audits, physical checks and policy guidelines," Parrikar told the Rajya Sabha in a written reply. "Defence services have established Cyber Emergency Response Teams (CERTs) to prevent and react to hacking attempts," the minister said.He said the security measures are adequate."While cyber-attacks are a major threat to national security, adequate measures to protect systems of armed forces are in place. Use of pen drive on internet linked computers is restricted and governed by Cyber Security Policy promulgated by ministry of defence," he said.