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Major DDoS attack on Dyn causes internet disruption

DNS provider Dyn experiences a large DDoS attack, causing disruption to online services

A distributed denial of service (DDoS) attack on domain name system (DNS) provider Dyn has caused disruption to online services worldwide.

Dyn reported that it was coming under attack at 11:10 GMT on the morning of Friday 21 September 2016. In a brief statement on its service status page, it said the attack was against its managed DNS infrastructure.

“Some customers may experience increased DNS query latency and delayed zone propagation during this time,” said the firm. “Customers with questions or concerns are encouraged to reach out to our technical support team.”

In a further update just after midday, it said: “This attack is mainly affecting US East and is affecting managed DNS customers in this region.”

At the time of writing, service disruption had been reported by AirBnB, Box, Github, Reddit, Spotify and Twitter.

DNS is a hierarchical and decentralised directory system that translates domain names, such as Computerweekly.com, into the numerical IP addresses that computers need to use to locate and identify services and devices.

DNS is considered a cog in the workings of the internet because if it did not exist, people would have to type numerical IP addresses into their browsers to access websites.

Dyn provides managed DNS services along with services such as load balancing, network monitoring and traffic management. Other providers of managed DNS services include Amazon, CloudFlare and Google.

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  • Thirty years after creating the internet's domain name system, co-creator Paul Mockapetris talks about addressing internet challenges with a more secure DNS
  • Three key methods for securing DNS, including how to monitor an enterprise’s DNS infrastructure traffic.

Richard Meeus, European vice-president of technology at DDoS mitigation specialist Nsfocus, said DNS was often neglected in terms of security and availability from an enterprise perspective, and Dyn was paying the price for this.

“It is treated as if it will always be there in the same way that water comes out of the tap and electricity is there when you switch it on,” said Meeus.

“This attack highlights how critical DNS is to maintaining a stable and secure internet presence, and that the DDoS mitigation processes businesses have in place are just as relevant to their DNS service as it is to the web servers and datacentres,” he added.

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