Distributed Denial-of-Service (DDoS) attacks have become the primary threat to the availability of networks and online services and the peak attack sizes have grown by a factor of more than 50 over the last 10 years. Today, botnets and easy-to-use tools for launching DDoS attacks have enabled a big increase in the number of attacks and the traffic they generate. As the attacks have evolved, so have the tools and services to stop them. The best current practice is to implement a strong hybrid defense that tightly integrates on-premise equipment for always-on protection with a cloud-based mitigation solution capable of handling the largest and most complex attacks.