What is a DDoS attack?

What is a DDoS attack?

A denial-of-service attack (DoS attack) or distributed denial-of-service attack (DDoS attack) is an attempt to make a service unavailable for its users. Often websites and web services are targets for a (D)DoS attack. The attackers use their resources, often bandwidth and CPU capacity from botnets, to flood the target with useless traffic and requests. This can result in unusually slow network performance, unavailability of a website or the inability to access any website. In a distributed denial-of-service attack multiple computers attached to the internet attack the target at the same time. A single computer often has too few resources to bring a website or web service down; combined resources can generate huge amounts of useless traffic.

An example of a DDoS attack is the attack on scientology by a group called Anonymous. They began attacking the websites of the scientology church in January 2008. The websites of the church of scientology have been hard to reach since.