DNS over HTTPS (DoH) is a privacy-enhancing technology that encrypts your DNS queries, preventing your internet service provider (ISP) and other potential eavesdroppers from seeing which websites you visit. Firefox, a popular and privacy-focused web browser, offers built-in support for DoH, allowing you to easily enable this crucial security feature. This guide will walk you through everything you need to know about using DoH in Firefox, from understanding its benefits to troubleshooting potential issues.
The Domain Name System (DNS) is the phonebook of the internet. When you type a website address (like www.example.com) into your browser, your computer uses DNS to translate that human-readable name into a numerical IP address that your computer can actually use to connect to the server. Traditionally, these DNS queries are sent in plain text, making them vulnerable to interception and manipulation.
DoH solves this problem by encrypting these DNS queries using HTTPS, the same protocol that secures your online banking and shopping. This encryption ensures that only your chosen DNS resolver and your computer can see your DNS requests, protecting your privacy and preventing malicious actors from performing DNS spoofing or other attacks.
Firefox makes enabling DoH relatively straightforward. There are generally two approaches:
Firefox automatically detects and uses DoH if your chosen DNS provider supports it. This is often the easiest and most convenient method. To check if it's enabled, go to about:preferences#privacy in your Firefox address bar. Look for the 'Network Security' section; you should see a setting for 'DNS over HTTPS' which will state it's 'Automatic'. If it's not enabled or you want to ensure you're using DoH, follow the next method.
If you want more control over your DoH provider, you can manually configure it. In about:config (be cautious here, as incorrect changes can affect your browser's functionality), you can find the following preference: network.trr.mode. Setting this to 2 (or changing the setting in Preferences if available) will enable DoH.
You may also want to specify your preferred DNS server. Common choices include:
You can specify a custom DNS server by setting network.trr.uri to the appropriate DoH URL for your chosen provider. Consult the documentation for your provider for the exact URL. For example, for Cloudflare, you might use https://cloudflare-dns.com/dns-query. You will have to restart Firefox for this to take effect.
If you're experiencing problems with DoH, here are some common issues and solutions:
Using DNS over HTTPS in Firefox is a simple yet highly effective way to enhance your online privacy and security. By encrypting your DNS queries, you can protect your browsing activity from unwanted observation and reduce your risk of falling victim to DNS-related attacks. Following the steps outlined in this guide will allow you to easily enable and configure DoH in Firefox, ensuring a more private and secure browsing experience.