DNS over HTTPS

DNS over HTTPS

DNS over HTTPS logo

DNS over HTTPS (DoH) is a protocol that allows DNS resolution to be performed over the HTTPS protocol. It aims to enhance privacy and security by encrypting DNS queries and responses, preventing eavesdropping and tampering.

Overview

DNS is a fundamental protocol used to translate human-readable domain names into IP addresses. Traditionally, DNS queries and responses are sent in plaintext, making them vulnerable to interception and manipulation. DoH addresses this issue by leveraging the encryption capabilities of HTTPS, which provides a secure and encrypted channel for communication.

When a user's device or application wants to resolve a domain name, it sends a DNS query to a DNS resolver. With DoH, this query is encapsulated within an HTTPS request and sent to a DoH server. The DoH server then performs the DNS resolution and returns the response encrypted within the HTTPS response. This ensures that the DNS queries and responses are protected from unauthorized access.

Benefits

Privacy

One of the primary benefits of DNS over HTTPS is improved privacy. By encrypting DNS queries and responses, DoH prevents third parties, such as Internet Service Providers (ISPs) or network administrators, from monitoring or intercepting DNS traffic. This helps protect user privacy and prevents the leakage of sensitive information.

Security

DoH also enhances security by preventing DNS spoofing and tampering. Since the DNS queries and responses are encrypted, it becomes difficult for attackers to manipulate the DNS resolution process. This helps protect against DNS-based attacks, such as DNS cache poisoning or man-in-the-middle attacks.

Bypassing DNS-based restrictions

Another advantage of DoH is its ability to bypass DNS-based restrictions imposed by certain networks or regions. In some cases, DNS queries may be blocked or redirected to enforce content filtering or censorship. By using DoH, users can bypass these restrictions and access the desired content without interference.

Implementation

To implement DNS over HTTPS, both the client and the server need to support the protocol. Clients, such as web browsers or operating systems, need to be configured to use a DoH resolver. Several popular web browsers have already integrated support for DoH, allowing users to enable it through their settings.

On the server side, DNS resolver operators need to deploy DoH servers that can handle the encrypted DNS traffic. These servers typically listen on port 443, the default port for HTTPS, and respond to DoH requests. Various open-source software and commercial solutions are available for setting up DoH servers.

Criticisms

While DNS over HTTPS offers numerous benefits, it has also faced criticism from certain stakeholders. Some network administrators argue that DoH can bypass network-level security measures, making it difficult to enforce content filtering or detect malicious activities. Additionally, DoH can introduce additional latency due to the encryption and decryption processes involved.

Conclusion

DNS over HTTPS is a protocol that enhances privacy and security by encrypting DNS queries and responses. It provides users with improved privacy, protection against DNS-based attacks, and the ability to bypass DNS restrictions. While it has faced criticism, DoH continues to gain popularity as more applications and devices adopt the protocol, contributing to a more secure and private internet experience.

See Also

• DNS
• HTTPS
• Domain Name System
• Internet Security
• Network Protocols