What is a DDoS attack?

A DDoS (Distributed Denial of Service) attack floods a website, server or internet connection with so much traffic from so many sources that real users can no longer get through. The traffic usually comes from a botnet of hijacked machines, so blocking one address does not help. Attacks are often used for extortion or to distract a security team while something else happens. Protection comes from your internet provider, your hosting provider or a dedicated DDoS mitigation service, which absorb the flood before it reaches you. A network detection tool inside your network does not stop a DDoS; it can help you see whether your own machines take part in one.

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