Most American businesses are expecting a major internet attack next year, according to a survey by the Business Software Alliance (BSA). Out of 600 network security managers interviewed, 60 per cent believe that the private sector is at risk of a concerted attack, possibly from terrorist groups, next year.

But only 18 per cent believe the sector will be able to cope with such attacks. BSA president Robert Holleyman described the findings as "sobering". "Many people think of cyber attacks as relatively harmless intrusions, but the reality is that the country's information networks are intricately linked and run everything from our power grids and emergency communication systems," he said.

He added that this underlined how network security has become a top priority for American politicians addressing national security in the wake of the 11 September terrorist attacks.