Who can protect UK in a cyber attack?
The skills of amateur ''cyber defenders'' are being put to the test in London this weekend, as they try to protect the UK against a simulated cyber attack.
Teams are competing in a scenario which involves a foreign government attacking the UK's financial systems.
As part of the exercise, competitors are shown simulated news reports, given briefings by the national defence community, and tip-offs by undercover operatives.
Gordon Corera reports.
15 Mar 2014