A new cyber attack unleashed this morning struck a number of popular websites such asTwitter, Netflix, Spotify and Amazon, resulting in these websites going down for an extended period of time. The attacks largely affected Internet users on the East Coast, and while most of the sites are back up and running, Twitter is still currently down on the West Coast. The distributed denial of service attack (DDoS) attack started around 7:10 AM ET, which was resolved around 9:30 AM ET, when a new wave of attacks began.

USA Todayreports that the web monitoring site Dyn started “monitoring and mitigating a DDoS attack against our Dyn Managed DNS infrastructure.” At 9:20 AM ET, they reported that services have been restored to normal, but just 32 minutes later, at 9:52 AM ET, they began monitoring a second DDoS attack. Amazon, whose web service AWS hostsNetflix, reported similar issues around the same time, but revealed that services were restored at 9:36 AM ET.

Other sites that went down this morning include Paypal,Reddit, Disqus, Github and Soundcloud. White House Press SecretaryJosh Earnestsaid the Department of Homeland Security was “monitoring the situation (but) at this point I don’t have any information about who may be responsible for this malicious activity.” Dyn didn’t disclose the source of the attacks at this time.

Dyn provides Domain Name Servers (DNS) that contains URLs and the Internet Protocol addresses they represent. Dyn’s DNS service provides theIP addressfor a number of websites, so your web browser knows which site to go to when a user types in a URL into a web browser. Here’s whatSteve Grobman, chief technology officer for Intel Security, had to say about this service.

“If you go to a site, say www.yahoo.com, your browser needs to know what the underlying Internet address that’s associated with that URL is. DNS is the service that does that conversion.”

TheDDoS attack"floods servers" with illegitimate requests which make it difficult for any real requests to go through. Service on some sites can still be intermittent, since a few requests may still be able to get through. As of now, no one has claimed responsibility for the attack, and it remains to be seen if another wave will happen later today.