Powerful Denial of Service attacks are becoming increasingly common. A Distributed Denial of Service attack is when the attacker uses multiple machines to flood the resources of the target to overwhelm it and deny the legitimate users access to the service. The DDoS attack on Dyn in October 2016 was one of most powerful attacks in history. Many DDoS attacks can be thwarted to a large extent by increasing the system’s capacity during an attack, but that is not a solution because it still causes monetary losses.