DNS Implementation Guidance

This document provides clarifications, surprises, and general guidance initially collected while implementing various parts of the DNS for the *domain* crate. It is an open source project and welcomes your contributions. You can submit an issue or pull request on the GitHub repository

The document follows the structure of the IETF’s DNS Terminology document, currently RFC 8499.

• Names
• DNS Response Codes
• DNS Transactions
• Resource Records
• DNS Servers and Clients
  • Notes about a message cache
  • QDCOUNT == 1 (most of the time)
  • When to close a TCP or TLS connection without TcpKeepalive options
• Zones
• Wildcards
• Registration Model
• General DNSSEC
  • Canonical RR Form
  • Signer’s Name
  • Duplicate Resource Records
  • Inception Time
  • DS Record At the Root
  • NSEC3 With Opt-Out Does Not Prove NODATA
• DNSSEC States