A denial-of-service attack is like an internet traffic jam

The attacks target companies and organizations, not individuals

Unlike a traffic jam, a denial-of-service attack is a deliberate strike from a hostile party. Hackers don’t target ordinary internet users. They strike against companies, organizations and government agencies. How­ever, hackers can use the devices of ordinary people in the attacks.

Often, the attacker aims to block access to a site or service, cause sense of insecurity, or test their opponent’s defense.

The more popular and important the service, the more damage an attack can cause. For example, disruption to banking and payment services can affect the lives of many people. Such a strike could momentarily stop payments or bank-based online authentication.

Your device can also be used in attacks

In a traffic jam, no one can move forward when there’s too much traffic. In a denial-of-service attack, a net­work congestion forms when multiple devices repeatedly try to connect to the same site at the same time.

When there are too many of these connections, the site slows down. Eventually it stops working completely. No one will be able to use the service until the congestion is lifted — or the attack repelled.

A computer that has been infected with a virus can be used as a tool for attacking. Hackers can take control of such devices and force them to constantly connect to the target. The owners of the infected devices usually know nothing about it. How­ever, such activity slows down the device and the internet connection. Malicious soft­ware can also down­load other malware to your device without your know­ledge.

Attacks do not pose a direct threat to you

Denial-of-service attacks can get a lot of publicity. How­ever, they do not usually cause long-term inconvenience to internet users. Often, attacked services are down for only some hours. Some­times it can take days to resolve the situation.

However, attacks can cause financial costs and reputational damage to businesses. Attacks can also create a general feeling of insecurity. Especially if some foreign state is believed to be behind them.