News

Windows 10 Preview Lets Users Test Encrypted DNS

• By Kurt Mackie
• 05/14/2020

Domain Name System (DNS) over HTTPS encryption, known as "DoH," can now be tested in a recently released preview version of Windows 10.

The encryption capability, promising greater privacy, can be tested by Windows Insider Program participants using Windows 10 build 19628 or higher. That build is already released to so-called "Fast Ring" (early release) Windows Insider Program testers, according to this Thursday Microsoft announcement.

Prospective DoH on Windows 10 testers will have to make specific Registry Editor changes and other configuration changes, as well as point their clients toward certain DNS servers that are participating in this pilot test program. The details are spelled out in this announcement, attributed to Tommy Jenson of the Windows Core Networking team.

Jensen had originally publicized Microsoft's DoH Windows efforts back in November, when he contended he was just describing Microsoft's future plans. Now, DoH on Windows 10 can actually be tested.

DoH is a proposed standard of the Internet Engineering Task Force that adds encryption when clients transmit URL requests over the Internet to servers. DNS Servers resolve these URLs into numerical strings, which are used to reach Web sites. For instance, the plain text "microsoft.com" URL resolves into "13.77.161.179."

Currently, when users request a URL without DoH, it's transmitted in plain text, and it can be seen by Internet Service Providers. The plain-text URLs possibly can be tampered with, too, when attackers carry out so-called "man-in-the-middle" attacks. DoH would encrypt those URLs, adding privacy protections for users, according to the concept.

Since the DoH capability is appearing in a Fast Release build of Windows 10, it's not yet clear if and when DoH will see the light of day in a production-grade release of Windows 10. It's just a work in progress right now.

"While features in the Active Development Branch may be slated for a future Windows 10 release, they are no longer matched to a specific Windows 10 release," Microsoft explained, in its Windows Insider "Flight Hub" document. "This means that builds from the active development branch simply reflect the latest work in progress code from our engineers."