If you were temporarily blocked from some websites this past Friday, you were probably experiencing the effects of a cyber attack. On Oct. 21, there was a major cyber attack, shutting down big websites such as Twitter, PayPal, Spotify, Reddit, and Netflix.

The cyber attack that occurred was more specifically labeled as a DDoS, or Distributed Denial of Service, attack. A DDoS attack is when someone floods a server with so much traffic that it makes it almost impossible to access the website. A DNS, or Domain Name Server, helps to route people to the correct website when someone types in a web address. By attacking a large DNS service provider, the hackers were able to prevent people from being routed to a website and thus, not being able to access it.

In this particular attack, a large DNS host by the name of “Dyn” was attacked by flooding their servers with junk traffic. Dyn called the attack, “well planned and executed, coming from tens of millions of IP addresses at one time.” The attacked started at 7 in the morning; it was fixed later by the afternoon, but the issues still persisted. Throughout the course of the day, Dyn experienced three waves of the attack. Initially, only the East Coast was affected, but by the afternoon people on the West Coast were being affected as well. This even reached as far as Western Europe.
This attack was unusual because, usually when there is a DDoS attack, only one website is affected by that attack. David Jones, a director of sales engineering at software IT company Dynatrace, said, “We’ve never really seen anything this targeted that impacts so many sites. Typically DDoS attacks are targeted at individual sites.” For now, the problems seemed to have been fixed and everything is running normally, but the FBI and the Department of Homeland Security are investigating the attack.