Google Public DNS now supports DNS-over-TLS

Posted by Marshall Vale, Product Manager and Puneet Sood, Software Engineer

Google Public DNS is the world’s largest public Domain Name Service (DNS) recursive resolver, allowing anyone to convert Internet domain names like www.example.com into Internet addresses needed by an email application or web browser. Just as your search queries can expose sensitive information, the domains you lookup via DNS can also be sensitive. Starting today, users can secure queries between their devices and Google Public DNS with DNS-over-TLS, preserving their privacy and integrity.

The DNS environment has changed for the better since we launched Google Public DNS over eight years ago. Back then, as today, part of Google Public DNS’ mission has been to improve the security and accuracy of DNS for users all over the world. But today, there is an increased awareness of the need to protect users’ communication with their DNS resolvers against forged responses and safeguard their privacy from network surveillance. The DNS-over-TLS protocol specifies a standard way to provide security and privacy for DNS traffic between users and their resolvers. Now users can secure their connections to Google Public DNS with TLS, the same technology that protects their HTTPS web connections.

We implemented the DNS-over-TLS specification along with the RFC 7766 recommendations to minimize the overhead of using TLS. These include support for TLS 1.3 (for faster connections and improved security), TCP fast open, and pipelining of multiple queries and out-of-order responses over a single connection. All of this is deployed with Google’s serving infrastructure which provides reliable and scalable management for DNS-over-TLS connections.

Use DNS-over-TLS today

Android 9 (Pie) device users can use DNS-over-TLS today. For configuration instructions for Android and other systems, please see the documentation. Advanced Linux users can use the stubby resolver from dnsprivacy.org to talk to Google’s DNS-over-TLS service.

If you have a problem with Google Public DNS-over-TLS, you can create an issue on our tracker or ask on our discussion group. As always, please provide as much information as possible to help us investigate the problem!