Reisalu said that in just five years, cyber threats have thoroughly changed old notions of security. "If what was achieved by cyber attacking Estonia in 2007 had been done with conventional weapons, it would have resulted at least in consultations of the North Atlantic Council and probably also invoking of Article 5," Reinsalu said.

According to US Department of Defense, some types of cyber attacks can now be treated as direct declaration of war. "Just like NATO provides deterrence of physical threats, we also have to find ways of establishing cyber deterrence which would send the attacker a clear message about potential consequences of such attacks," he said.

The international cyber security conference CyCon, organized by the NATO Cooperative Cyber Defence Centre of Excellence in Tallinn and running through June 8, discusses legal, political, strategical and technical aspects of military and paramilitary action in cyber space. Over 400 participants from all over the world include academic researchers, politicians, IT-pundits and strategists.

Erkki Sivonen