Most important RFCs
Mail
- 2821: Simple Mail Transfer Protocol
- 822: Standard for ARPA Internet Text Messages
- 2045: Multipurpose Internet Mail Extensions (Part One)
- 2505: Anti-Spam Recommendations for SMTP MTAs
HTTP and Related
- 2616: Hypertext Transfer Protocol -- HTTP/1.1 (Errata)
- 2396: Uniform Resource Identifiers (URI): Generic Syntax
- 1630: Uniform Resource Identifiers in WWW
- 2183: The Content-Disposition Header Field
DNS
- 1912: Common DNS Errors (Informational)
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