One of the things we don't talk about much at CloudFlare is how we've built one of the largest, fastest, easiest, and most resilient authoritative DNS networks in the world. A report from SolveDNS was just released that shows CloudFlare as the second fastest authoritative DNS provider, well ahead of companies EasyDNS, UltraDNS, and Verisign.
Company | Average Speed (ms) | Min | Max | Standard Deviation | AnyCast ------------ | --------------------- | --------- | --------- | ------------------------ | ------------- He.net | 6.77 | 4.49 | 10.28 | 2.37 | Yes CloudFlare | 7.45 | 4.44 | 33.48 | 3.80 | Yes Dyn | 8.37 | 4.81 | 21.42 | 4.01 | Yes DNSMadeEasy | 9.46 | 4.27 | 17.70 | 5.10 | Yes VerisignDNS | 22.34 | 5.13 | 56.43 | 24.04 | Yes Netriplex | 29.81 | 5.38 | 82.96 | 28.13 | Yes UltraDNS | 44.96 | 4.39 | 81.44 | 26.47 | Yes Nettica | 48.97 | 29.14 | 79.95 | 19.12 | No ZoneEdit | 64.65 | 18.19 | 142.16 | 38.62 | No EasyDNS | 76.42 | 3.70 | 163.86 | 62.08 | Yes
(data from SolveDNS August 1, 2012 report)
CloudFlare runs an authoritative DNS network in order to make provisioning our performance and security services as easy as possible. Because we're relentlessly focused on making the web faster, we built our DNS infrastructure to be as fast as possible. While we give you two name server domains when you sign up for CloudFlare, the reality is that those domains reference clusters of servers in each of our 17 (soon to be 23) data centers worldwide. That's quite different than the average registrar's DNS infrastructure, and part of the secret on how we're so fast.
Any Server Can Answer Any DNS Query
We've written about Anycast before, but it's an important technology we use to make DNS fast and highly available. Where traditionally, one IP corresponds to one server on the Internet, with Anycast multiple servers in distinct locations announce the same IP address and traffic is automatically routed to the one that is closest to the system making the request. If a server (or entire data center) goes offline, traffic immediately and seamlessly fails over to the next-closest location.
Since CloudFlare is provisioned via DNS, we set out from the beginning to make the fastest, most fault-tolerant DNS network in the world. In fact, every server we run in every data center around the world can answer any DNS query for any one of our clients. While this is built for redundancy and stability, the side effect is that it's extremely fast. And, as we continue to build out our global network, our DNS speeds will continue to get even faster.
The DNS providers listed in the SolveDNS chart all specialize in DNS service and most run Anycasted networks (although few are as large as CloudFlare's). Many people continue to use their registrar's DNS, which is puzzling since they're often overloaded and slow. Since every request for a domain starts with a DNS query, a slow DNS provider is a hidden tax on your website's performance. With fast, free solutions like CloudFlare, it's a puzzle why anyone puts up with slow DNS.
When CloudFlare was first getting started we knew that DNS was going to be critical. Before we deployed a single server we started to focus on every aspect of DNS, even the control panel for customers to interface with it. We'd been frustrated by the state of DNS control panels, whose UI providers woefully underinvest in. We spent several months surveying every DNS provider in the world to see if we could build a better DNS UI. The result, we think, is the easiest to use DNS control panel in the world.
Beyond ease of use, the way that CloudFlare's DNS infrastructure works means updates are extremely fast. It takes less than a second for a change from the DNS control panel to be propagated across our entire network. And, since you can change your backend server's IP address without having to change the IP CloudFlare announces to the world, the result is you can change from one backend server to another without having to wait for DNS propagation. It's pretty slick.
We're continuing to make additional improvements to both our DNS infrastructure and how it is deployed by our customers. One of the requested features from businesses was that they wanted custom DNS servers that used their own domain name, not CloudFlare. As a result, that feature is now included with all Business and Enterprise plans. Going forward, CloudFlare will begin offering its massive DNS infrastructure and custom name servers to hosting provider partners so they can ensure their customers have the fastest, most resilient DNS service without requiring any name server changes.
So while we don't talk about it much, we're spending a ton of time thinking about DNS. As John Graham-Cumming on our team just suggested, "We clearly need to change our name to something like KickassDNS." That's probably not going to happen. But, if you've ever hesitated to sign up for CloudFlare because you were concerned about changing your DNS, chances are we'll be significantly faster and more resilient than whatever you were using before.