How A Single Attack Can Take Down A Big Chunk Of The Internet

Much of the U.S. woke up to find a cyberattack had slowed down or outright blocked access to a bunch of big-name websites. But how does a single attack take down Twitter, Spotify and Soundcloud all at once?

Simple: It hits the right part of the network: the address book.

The Domain Name System is the internet's directory. When you type a website into your browser, the DNS translates that text into the unique address of the server you're looking for. 

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Dyn is one of the companies that sells domain name services to clients like Twitter and Soundcloud. So most of the traffic to those sites goes through Dyn's own servers.

Dyn says attackers bombarded their servers with a bunch of junk traffic — so much that they slowed down or stopped working. And when those servers went down, they took a lot of Dyn's clients down with them.

 Outages have continued, but the good news is attacks like this can eventually be stopped. DNS providers are typically able to filter out bogus traffic and restore service to normal within hours.