Facing up to threat of cyberwar
Military experts gathered in London this week to discuss the growing threat of cyber-attacks to international security.
The US is aiming to recruit 10,000 "cyberwarriors" to try to combat the problem, which poses risks to everything from power grids and water supplies to businesses and individuals.
Australian authorities have warned financial firms about a flood of attacks on their websites, while on New Year's Day banks in South Africa were hit by a multi-million pound cyber-attack.
Meanwhile, in the Middle East, a series of escalating incidents between Arab and Israeli hackers has involved computer worms and leaked personal information.
Newsnight's Susan Watts reports.
Broadcast on 26 January 2012