Police are investigating the hacker attack that drove UK ISP Cloud Nine out of business.

The police are currently gathering evidence into the demise of UK ISP Cloud Nine Communications. It’s not unusual for an Internet company to go out of business, but Cloud Nine, which had been in business for almost six years, was not the victim of an unsustainable business model. It was the target of a series of attacks against its web servers, which took its email and DNS servers offline.

The assault effectively prevented Cloud Nine’s users from accessing the Internet – and since the current state of the market for small ISPs leaves little room for maneuver, the ISP was unable to recover. It has closed down, selling its customer base and assets to former rival Zetnet.

While Cloud Nine is one of the first major companies to be put out of business by dedicated denial of service (DDoS) attacks, the attacks are not uncommon. In recent years, high-profile companies such as Amazon.com, CNN, ZDNet and Etrade have been targets for such attacks, where victims’ networks are flooded with traffic so that authorized data gets lost in a sea of misinformation and systems become clogged.

Not only was Cloud Nine irreparably damaged by the attacks, but many of the ISP’s business customers also suffered after their own operations were disrupted. And while the company admitted that the problem was partly caused by its own shortcomings, the latest attacks were so major and vicious that there was little the ISP could have done to resist them.

The cause of the DDoS strikes on Cloud Nine is not yet known. Although it is unlikely that this event is related to the September 11 attacks, its powerful effect cannot have failed to impress the many disillusioned groups around the world – who will use any weapon in their arsenal to disrupt businesses and economies alike. With such a dramatic impact, a new wave of DDoS attacks is almost certainly just around the corner.