| 2119 | Key words for use in RFCs to Indicate Requirement LevelsS. Bradner | Best Current Practice | March 1997 |
| 3553 | An IETF URN Sub-namespace for Registered Protocol ParametersM. Mealling, L. Masinter, T. Hardie, G. Klyne | Best Current Practice | June 2003 |
| 3986 | Uniform Resource Identifier (URI): Generic SyntaxT. Berners-Lee, R. Fielding, L. Masinter | Internet Standard | January 2005 |
| 4648 | The Base16, Base32, and Base64 Data EncodingsS. Josefsson | Proposed Standard | October 2006 |
| 5246 | The Transport Layer Security (TLS) Protocol Version 1.2T. Dierks, E. Rescorla · obsoleted by RFC 8446, RFC 9846 | Proposed Standard | August 2008 |
| 5280 | Internet X.509 Public Key Infrastructure Certificate and Certificate Revocation List (CRL) ProfileD. Cooper, S. Santesson, S. Farrell, S. Boeyen, R. Housley, W. Polk | Proposed Standard | May 2008 |
| 5652 | Cryptographic Message Syntax (CMS)R. Housley | Internet Standard | September 2009 |
| 5912 | New ASN.1 Modules for the Public Key Infrastructure Using X.509 (PKIX)P. Hoffman, J. Schaad | Informational | June 2010 |
| 6066 | Transport Layer Security (TLS) Extensions: Extension DefinitionsD. Eastlake 3rd | Proposed Standard | January 2011 |
| 6234 | US Secure Hash Algorithms (SHA and SHA-based HMAC and HKDF)D. Eastlake 3rd, T. Hansen | Informational | May 2011 |
| 6268 | Additional New ASN.1 Modules for the Cryptographic Message Syntax (CMS) and the Public Key Infrastructure Using X.509 (PKIX)J. Schaad, S. Turner | Informational | July 2011 |
| 6960 | X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSPS. Santesson, M. Myers, R. Ankney, A. Malpani, S. Galperin, C. Adams | Proposed Standard | June 2013 |
| 6962 | Certificate TransparencyB. Laurie, A. Langley, E. Kasper · obsoleted by RFC 9162 | Experimental | June 2013 |
| 6979 | Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA)T. Pornin | Informational | August 2013 |
| 7231 | Hypertext Transfer Protocol (HTTP/1.1): Semantics and ContentR. Fielding, Ed., J. Reschke, Ed. · obsoleted by RFC 9110 | Proposed Standard | June 2014 |
| 7633 | X.509v3 Transport Layer Security (TLS) Feature ExtensionP. Hallam-Baker | Proposed Standard | October 2015 |
| 7807 | Problem Details for HTTP APIsM. Nottingham, E. Wilde · obsoleted by RFC 9457 | Proposed Standard | March 2016 |
| 7841 | RFC Streams, Headers, and BoilerplatesJ. Halpern, Ed., L. Daigle, Ed., O. Kolkman, Ed. | Informational | May 2016 |
| 8032 | Edwards-Curve Digital Signature Algorithm (EdDSA)S. Josefsson, I. Liusvaara | Informational | January 2017 |
| 8126 | Guidelines for Writing an IANA Considerations Section in RFCsM. Cotton, B. Leiba, T. Narten | Best Current Practice | June 2017 |
| 8174 | Ambiguity of Uppercase vs Lowercase in RFC 2119 Key WordsB. Leiba | Best Current Practice | May 2017 |
| 8259 | The JavaScript Object Notation (JSON) Data Interchange FormatT. Bray, Ed. | Internet Standard | December 2017 |
| 8391 | XMSS: eXtended Merkle Signature SchemeA. Huelsing, D. Butin, S. Gazdag, J. Rijneveld, A. Mohaisen | Informational | May 2018 |
| 8446 | The Transport Layer Security (TLS) Protocol Version 1.3E. Rescorla · obsoleted by RFC 9846 | Proposed Standard | August 2018 |
| 8820 | URI Design and OwnershipM. Nottingham | Best Current Practice | June 2020 |