How does Anycast DNS work?

The Domain Name System (DNS) is one of the foundations of the Internet, yet most people outside of networking probably don’t realize they use it every day to do their jobs or check their email. Anycast DNS helps using the Internet to be even faster and efficient. Let’s talk about that a little bit more.

What is Anycast DNS?

When you choose Anycast DNS as your routing method, you can establish your IP address in several DNS servers.

Through Anycast, different servers positioned in many geographical locations are capable of answering the query. The closest of them will provide the IP address to the user. 

Also, if one of the DNS servers is down for some reason, the second closest server will receive the request. 

Experience is faster and better with Anycast DNS when we speak about loading time, waiting for a response, etc.

Before we continue, let’s explain a little bit more about what DNS is.

What is DNS? 

The Domain Name System (DNS) is a complex infrastructure that helps translate human-readable hostnames (like into computer-readable IP addresses (like So, DNS eliminates the need for humans to memorize all of the IP addresses. 

It operates by pairing domain names with their corresponding IP addresses each time we request websites through our browsers. 

DNS takes the role of a phonebook of the Internet. Imagine remembering all of those numbers for every website you want to visit. It sounds impossible, right?

Benefits of Anycast DNS 

  • Setup is easy! – Configure it in only one server, and such settings can be spread to the whole network.
  • DDoS protection – If a DDoS attack is initiated, only a piece of the whole Anycast DNS group will be affected.
  • Better response time: Redirecting to the nearest DNS server will provide a decrease in the response time.
  • Increased Reliability – With Anycast, you can improve the reliability of DNS through the arrangement of multiple geographically separated servers at the same IP address. The redundancy of these DNS servers makes the service more highly available and reliable.

Anycast DNS Alternative

The alternative Unicast DNS is the exact opposite of Anycast DNS. The DNS information is stored in one particular server. So when someone wants to visit your site, it will check exactly that server regardless of their location. 

Also, unfortunately, if your server crashes or under attack, your site will no longer be accessible.

Broadcast is a term that is familiar from TV and radio. It means that the information is carried from one point to all. Packets are routed to all possible endpoints on the broadcast network. As you probably guessed, if DNS was using the broadcast method, the whole Internet would be impossible to use.

Multicast: Information is transferred from one to many. Only the gathering who is interested in the traffic receive it. This routing method is useful when there are no local nameservers. If a computer from this type of group needs an IP address, it will send a query, and the answer will get back to all of the connected devices to that group. The IP address will be saved in the mDNS cache on the devices. 

Do you know what the Dynamic DNS is?


Internet would be a strange place without DNS, for sure. Anycast DNS is a perfect option for a fast and reliable routing method. It has advantages and can boost network performance significantly.

So, what do you think about Anycast DNS now?

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