Anycast upgrades mean faster DNS response

Written on 27 June, 2014 by Jonathan Gleeson
Categories DomainsNewsTags dnszone records

Netregistry has completed upgrades to its top-of-the-line Anycast DNS infrastructure, including adding an additional node in Perth. Over the next few months we will be adding more nodes in New York City, Hong Kong and London. These new locations, along with our existing locations in Sydney, Kuala Lumpur, San Francisco and Amsterdam, will bolster the reliability and speed of our DNS system.

But how does it work and why is it important?

Anycast is a network addressing and routing methodology in which datagrams from a single sender are routed to the nearest node in a group of potential receivers (though it can also be sent to several nodes all identified by the same destination address).

In simpler terms, we have DNS servers all around the world that all look like the same server. Your DNS requests go to the server which is geographically nearest to your location.

This provides two main benefits:

1. Anycast makes DNS more reliable

When we deploy identical servers at multiple nodes on multiple networks, in widely diverse geographical locations, all using Anycast, we have effectively added global load-balancing functionality to our DNS service. Importantly, the load-balancing logic is completely invisible to the DNS servers. Instead, it's moved down the stack from the application to the network layer. Because each node advertises the same IP address, user traffic is shared between servers globally and handled transparently by the network.

2. Anycast improves DNS performance

On the Internet, having a fast site is not only a user experience issue. Now, the speed at which pages load is allegedly a factor in search engine rankings. Naturally, anything an organisation can do to improve performance is desirable, and Anycast can help with that objective.

By allowing clients to reach the DNS server closest to them, the latency associated with multiple hops can be reduced and potential network bottlenecks between the user and the name server become irrelevant. If there's an Anycast resolver node hosted at the DNS client's nearest large Internet exchange, there's no need for their query to make an intercontinental round-trip before it can get on with the important business of retrieving web pages.

It is not easy to set up a true Anycast network. It requires significant hardware, direct relationships with global upstream carriers, and highly tuned networking routes. We've taken the time to do that at Netregistry so we can ensure all our users have access to a faster, more reliable, service.