Home Resource Center Glossary Denial of Service (DoS)

Denial of Service (DoS) is an attack where one computer and one Internet connection inundates a targeted system or resource. When an army of remotely controlled computers inundates all your resources, that’s called a Distributed Denial of Service (DDoS) attack. Both types of attacks attempt to prevent internal employees and customers from accessing an organization’s web-based service by either flooding the servers or crashing them.

There are two main types of DoS attacks: attacks designed to exhaust application or server resources and attacks that simply flood services. Application attacks exploit application vulnerabilities or business logic to bring down a service. Examples of application DoS attacks include Slowloris, which initiates many connections to a targeted server and never closes the connections, and buffer overflow attacks. Network attacks like SYN flood, ICMP flood, and UDP flood attacks are almost always performed by multiple attack sources as part of a DDoS attack.

DDoS attacks are increasing in both frequency and scale and have left some of the world’s largest data center and network operators dealing with their costly aftermath. Virtually every commercial and government organization is reliant on the availability of their online services, and service availability is wat risk from the rising tide of DDoS attacks. If you are concerned about the possibility of major service outages due to DDoS attacks, make sure that your networking vendor can scale to mitigate the largest multi-vector attacks at your network’s edge.

Learn how A10 helps organizations mitigate a DDoS attack. Download the white paper titled DDoS Attack Report: The Escalating Threat of DDoS Attacks.