Description: Denial of Service (DoS) is a type of cyber attack aimed at making a service unavailable to its intended users. This type of attack is carried out by flooding a server, service, or network with excessive traffic, causing resources to become exhausted and the service to become inoperable. Denial of service can be executed in various ways, including sending massive requests that the system cannot handle or exploiting vulnerabilities in the software to cause failures. The main characteristic of a DoS attack is its intention to disrupt the normal functioning of a service, affecting availability and, in some cases, data integrity. This type of attack is especially relevant in the context of network security, as it can have devastating consequences for businesses and organizations that rely on the constant availability of their online services. Denial of service can also be used as a distraction tactic in more complex attacks, where the ultimate goal is to infiltrate systems or steal sensitive information.
History: The concept of denial of service dates back to the early days of the Internet, but it gained popularity in the 1990s. One of the first documented DoS attacks occurred in 1996 when a group of hackers launched an attack against an Internet service provider’s website. Over the years, the technique has evolved, and in 2000, a massive DoS attack occurred against Yahoo!’s website, rendering the service inoperable for several hours. This event marked a turning point in awareness of online security and led to an increase in research and development of defense measures against these attacks.
Uses: Denial of service is primarily used as an attack tactic in the hacking realm, where attackers seek to disrupt access to critical services. It can also be used as a form of protest, known as hacktivism, where groups attempt to draw attention to social or political causes. Additionally, in the field of network security, denial of service is studied to develop better defenses and mitigation strategies.
Examples: A notable example of a denial of service attack was the DDoS (Distributed Denial of Service) attack that affected Dyn, a DNS service provider, in October 2016. This attack disrupted access to numerous popular websites, including Twitter, Netflix, and Reddit. Another case is the DoS attack that GitHub suffered in 2018, which was one of the largest recorded, reaching traffic peaks of 1.35 terabits per second.
