IT contractors may be required to help small businesses beef-up the security on their wi-fi networks, following the publication of a new report.

Hacker Jason Hart of CyrtoCard travelled to six cities in the UK to carry out "ethical hacking" on behalf of identity fraud specialist CPP.

Mr Hart found that half of the 40,000 networks he identified on his travels were operating either without a password or only with the most basic form of encryption, which could be hacked in seconds using simple, downloadable software.

The hackers were able to harvest usernames and passwords at a rate of more than 350 an hour, despite more than 82 per cent of people and small firms thinking their networks are secure.

"It's vital that both businesses and individuals think very carefully about network security and what information they provide when going online," said Mr Hart.

A recent announcement from Ofcom will mean more people will get access to cheap superfast broadband.