Critical sections of the UK IT infrastructure will come under attack this week as the US Department of Homeland Security runs Operation Cyber Storm, a global penetration test to assess how vulnerable the nation is to online attack.

An anonymous source has confirmed to US publication Federal Computer Week that the exercise will be global in scale and include attempted penetration of key UK infrastructure, as well as targets in the US, Canada and Australia. 

The US National Cyber Security Division is funding the testing programme and Donald Purdy, its acting director, told Congress in October that such a test was being planned.

The Department of Homeland Security confirmed in November that the original plan was to hold the test in November but that the response to hurricanes Katrina and Rita forced a rescheduling for February.

Penetration tests will be conducted on financial institutions, power companies and other users of critical IT systems.