CYBERCRIMINALS are making a mint bringing e-commerce firms to a standstill with distributed denial of service attacks (DDoS), according to the UK's National Criminal Intelligence Service.

In a report issued on 3 August, called the 2005 UK Threat Assessment (www.ncis.co.uk/ukta.asp) the NCIS details cases from 2004 in which a gang based in Russia used a botnet, a network of virus-infected computers, to flood several online gambling websites with useless data, so they couldn't trade with their users.

The extortionists' botnet had a total bandwidth of 3 to 4 gigabits per second, exposing the firms' servers to the equivalent of 200,000 emails per second. "The attacks were soon followed by an extortion demand, often for no more than $5000," says the NCIS. "As some companies were losing £100,000 an hour while under attack, many chose to pay up."