What is Anycast DNS

What is Anycast DNS and how it works?

What is Anycast DNS?

It might seem natural when websites load fast. Your lookups, (or web inquiries) are quick and efficient when you are shopping online, making restaurant reservations, or chatting across continents. What makes it all run smoothly is the Domain Name System (DNS). Because computers communicate using numbers, the DNS translates human-readable hostnames (such as yourbusiness.com)  to machine-readable IP addresses (such as 201.002.01.10). 

To speed things up further, busy websites used all over the globe for e-commerce, streaming, video chat, or any kind of large file transfer have usually chosen Anycast DNS to be their website DNS. 

Because Anycast stores your website’s DNS records on multiple servers (known as points of presence or PoPs) using one IP address, you can upload content to your website from a set host location, yet have a website presence everywhere. This is your website’s Anycast IP address which locates all your DNS records, but now this information is stored redundantly (as a copy) on many servers. The result? Faster access for all those lookups.

How Does Anycast DNS Work?

Once your website is stored by Anycast, website queries are dispersed across the Anycast network. This expands the capacity of your website to deal with visitors. Any requests are met by the closest powerful global PoP to the visitors’ location. This way, it doesn’t really matter where your website is hosted from, because with Anycast, it becomes hosted all over the world. 

To compare, if you were just using a normal DNS service, or a free service to host your website, your IP address and DNS records would only live within one or two nameservers. Because fast page load times are essential for e-commerce and mission-critical websites (which need real-time global updating) many prefer Anycast DNS (such as the service offered by Namecheap’s PremiumDNS) to ensure speedy website queries. 

The DNS service has an impact on eCommerce sales because faster website accessibility results in more transactions. Time is money. One mission-critical example is the New York Stock Exchange website. It’s essential to have real-time global updates on prices when the average amount of shares traded equals 2.4 billion per day.

What Anycast can do for websites

Because Anycast uses global points of presence (PoPs), or powerful servers in many continents, you no longer have to rely on one or two nameservers in one geographical location — which is what basic and free DNS services offer. 

Some of these security implications are helpful to website owners.

Page speed power

By selecting to send queries by a process known as efficient routing, page loading speeds are fast for visitors, and webpages are always available. 

Big bandwidth boost

If any server is overwhelmed or too busy,  Anycast would simply re-route a visitor’s query to the next closest server to their location.

Fast configuration

If you change DNS records for your website, these changes are near-instantaneous. 

The last point is why many CDNs (such as Namecheap’s Supersonic CDN) use the Anycast network too, as a content delivery system. Businesses using Anycast CDNs can ensure content uploads populate worldwide super fast. CDNs using Anycast can both segment traffic to websites, with load-balancing techniques, and send users requesting content to the closest server to them, improving speeds.

Will Anycast DNS help my website?

No one likes slow websites or websites which give ‘denial of service’ messages. How quickly visitors receive your website is directly connected with how near to them is a server storing your DNS records. Therefore, any website with global queries benefits when using Anycast. 

Main advantages of Anycast DNS for websites

Customers and clients who are trying to look up your website, buy from you, or engage with your content will be happy if your website is using Anycast DNS. Their query will always be answered; and fast! 

Reduced Latency. From one IP address located on multiple global servers, users can look you up from the closest server to them, geographically. This results in less latency and improves uptime because the distance a query travels is much shorter.

Protection from DNS DDoS Amplification attacks. Anycast defends your website from distributed denial of service (DDoS) amplification of queries. This cyberattack is from an infected host server. Anycast will re-route your website queries away from servers overwhelmed by the infected hosts and your website visitors won’t experience denial of service.

Protection from DNS DDoS Flood attacks. Anycast protects against DNS flood attacks which try to overwhelm DNS resolver servers with excess queries for DNS records. Anycast uses sophisticated algorithms to deploy load-balancing. This spreads the queries both across the Anycast network and to the next nearest available server to your visitor. 

Powerful DNS availability. Because visitor traffic is efficiently routed and the network is much bigger than one or two servers, your website DNS won’t go offline. 

Increased DNS connection reliability. Anycast DNS efficiently re-routes services if one or more of a group of DNS servers fail.

One IP address simplifies DNS configuration. Anycast DNS simplifies the configuration of client DNS resolvers because one nameserver IP address is easier for resolvers to remember.

Anycast DNS Alternatives

The Internet Protocol allows five addressing methods. Here we have discussed Anycast, being a one-to-one communication method between senders and destinations, using complex algorithms designed for geolocation efficiency. What might the others be?

Unicast sends a message one-to-one making this a very secure way to send a packet, and is commonly used by sensitive communications such as in banking. 

Broadcast can be thought of as one to all communication. Content packets are routed to endpoints in the broadcast network such as live television networks, where all endpoints (such as your home television) can receive a live transmission.

Multicast communication travels as one-to-many and then more. Transmission is routed to multiple recipients. The difference is that users choose to receive the content. Services such as cable TV use multicast to allow viewers to select a program that has already been sent and then choose to watch it at some point in time.

Geocast is a form of multicast, where you can target content to reach a group of destinations by geographical location. Mostly used by companies for internal purposes and security, and government communications who want to limit how many possible recipient clients/devices can access their content.

Anycast for websites

The DNS underpins all we do on the Internet, connecting billions of us to websites we want to see every day. Consider how your efforts to bring traffic to your website are wasted if customers can’t trust your website connection, or can’t buy from you once they arrive on-site because of denial of service.

Having the service is one of the best ways to beat hackers who are trying to disrupt your web property. Anycast DNS gives you maximum uptime, availability, and DNS speed.

Does Namecheap offer Anycast?

Yes, with PremiumDNS, which is one of the most cost-effective, high-performance DNS services around for the money, and Supersonic CDN for Anycast content delivery.

For more detail on the benefits of both PremiumDNS and CDN please visit:

Or if your interest is in how both services protect you from DDoS check out:

For your website to enjoy a stable and secure connection and not suffer downtime, Anycast DNS and Anycast CDNs will save you time, money and be worth the investment. When you think about how much each year is spent on advertising, these technology products offer security, speed, and peace of mind for much less than the average spend for clicks.


Lisa McKnight

Lisa McKnight

As a digital technology copywriter, I'm passionate about communicating how vital the information industry is and how stuff works. If it's complicated I believe it can also be engaging. With 10 years of copywriting in B2B and B2C marketing, technology is rocking my world.
More articles written by Lisa.

Join Our Newsletter

Stay inspired

Get all the latest offers, articles, and industry news straight to your mailbox every month.

Need help? We're always here for you.