Anycast DNS service explained.
Anycast DNS service is an additional feature that most DNS providers offer. It is a beneficial mechanism for routing the traffic, which delivers the content of websites really quickly. That is possible thanks to the several nameservers that store a particular identical IP address.
For the purpose of being closer to the potential users, each of these servers is placed in various geographical areas. That way, the responses to the DNS queries are way faster, and the user experience is improved. The one server which is most closely and also available is going to respond to the user’s request. So, the Anycast DNS service reduces the latency to almost a minimum, and your clients won’t wait a lot to reach and explore your website.
Besides, in cases when the nearest server is not able to answer, for instance, when it is under maintenance, your website is still going to be accessible. Thanks to the ability to choose the fastest route, the DNS resolution is achieved very briefly.
- It is simple to set it up! – You just have to make the configuration on a single server. The settings are going to be distributed to the entire network.
- You benefit from DDoS protection. – If one of your name servers is under a DDoS attack, you won’t have to worry! The rest of the servers in the Anycast DNS group are still going to operate.
- It improves faster response time. Taking the short path to the closest name server is the key in this situation. Your users are going to take advantage of fast answers.
- Load balancing mechanism. Thanks to the numerous servers replaying to their nearby users, the traffic load is spread, and it is not overwhelming a single server. That is a great way to implement the popular technique – load balancing.
- It improves reliability. Thanks to the Anycast DNS service, you increase the reliability of DNS with the arrangement of numerous geographically divided servers with the same IP address. In addition, the redundancy of these name servers causes the service to be more highly available and reliable.
Anycast DNS service vs. Unicast DNS service
- When we are using Unicast DNS routing, the DNS recursive server obtains a set of numerous DNS name servers. It starts its search through the first one and remains until the server responds, or there is a timeout. Only then is it capable of searching the information on the second one. That causes unwanted latency.
- When we are using Anycast DNS, the DNS recursive server gets a single anycast address for each group of DNS servers. That way, the latency is just not possible. The recursive server is not pausing due to not responding DNS server. The Anycast DNS service excludes points of presence (PoPs) that could not be reached. As a result, the DNS recursive server is routed to the closest and available name server.