DNS Encryption Technical Reference

DNS Encryption Technical Reference

A comprehensive technical guide to DNS encryption protocols, Bloqr’s architecture integration, performance analysis, and implementation details for developers and infrastructure teams.

DNS Encryption Protocols

DNS over HTTPS (DoH) - RFC 8484

DoH encapsulates DNS queries as HTTP requests on port 443.

Advantages:

• Firewall-friendly (standard HTTPS port)
• Works through most proxies
• Widely supported

Disadvantages:

• HTTP overhead
• Slightly more latency than DoT

DNS over TLS (DoT) - RFC 7858

DoT wraps DNS in TLS using dedicated port 853.

Advantages:

• Lower overhead than DoH
• Native DNS wire format
• Better for high-volume resolvers

Disadvantages:

• Dedicated port 853 may be blocked
• Less device support than DoH

DNS over QUIC (DoQ) - RFC 9250

DoQ uses QUIC for DNS, combining DoT efficiency with multiplexing.

Advantages:

• 0-RTT resumption
• Full multiplexing support
• Future-proof

Disadvantages:

• Limited device support
• Not yet widely deployed

Performance Characteristics

Protocol	First Query	Cached Query	Notes
DoH	50-150ms	10-30ms	HTTP overhead
DoT	30-80ms	5-15ms	Lower overhead
DoQ	0-5ms	5ms	With 0-RTT

Cloudflare 1.1.1.1

Cloudflare offers encrypted DNS with:

• Zero-query logging policy
• Global anycast network (14ms avg latency)
• Blocks malware by default
• Free for everyone

Related Documentation

• DNS Encryption & Privacy Guide - User-friendly guide
• Client Libraries - Integration examples
• API Reference - Build custom solutions