DNS over HTTPS (DoH): Enhancing Privacy and Security in Internet Browsing

 DoH (DNS over HTTPS)

What Is DoH (DNS over HTTPS)?

DNS over HTTPS (DoH) is a protocol that encrypts DNS queries using HTTPS, thereby enhancing privacy and security by preventing third parties from seeing which websites a user is attempting to access.

Why DNS Matters

The Domain Name System (DNS) translates human-readable domain names (such as example.com) into IP addresses that computers use to locate one another on the internet. Traditionally, DNS queries are sent in plain text, making them vulnerable to:

• Eavesdropping
• Manipulation (DNS spoofing or hijacking)
• Tracking by ISPs or malicious actors

How DoH Works

Instead of sending DNS queries over UDP or TCP in plain text, DoH:

1. Encapsulates DNS queries within HTTPS requests.

2. Sends them to a DoH-compatible DNS resolver (like Cloudflare, Google, or Quad9).

3. Receives encrypted responses, protecting the query from interception or modification.

This means DNS traffic is mixed with regular HTTPS web traffic, making it harder to detect or block.

Key Benefits

• Privacy: Prevents ISPs and network admins from seeing DNS queries.
• Security: Protects against DNS spoofing and man-in-the-middle attacks.
• Integrity: Ensures DNS responses are authentic and untampered.

Considerations & Controversies

Centralization: DoH often routes DNS traffic through large providers (e.g., Google, Cloudflare), raising concerns about data concentration.

Network Management: This makes it harder for organizations to monitor or filter DNS traffic for security or compliance purposes.

Compatibility: Not all devices or networks support DoH, and it may conflict with enterprise DNS policies.

DoH vs. Other Secure DNS Protocols

Adoption

Major browsers, including Firefox, Chrome, and Edge, support DoH. Operating systems like Windows 11 and Android also offer system-level DoH settings.