| 20 | ASCII format for network interchangeV.G. Cerf | Internet Standard | October 1969 |
| 2119 | Key words for use in RFCs to Indicate Requirement LevelsS. Bradner | Best Current Practice | March 1997 |
| 2865 | Remote Authentication Dial In User Service (RADIUS)C. Rigney, S. Willens, A. Rubens, W. Simpson | Draft Standard | June 2000 |
| 3454 | Preparation of Internationalized Strings ("stringprep")P. Hoffman, M. Blanchet · obsoleted by RFC 7564 | Proposed Standard | January 2003 |
| 3490 | Internationalizing Domain Names in Applications (IDNA)P. Faltstrom, P. Hoffman, A. Costello · obsoleted by RFC 5890, RFC 5891 | Proposed Standard | March 2003 |
| 3491 | Nameprep: A Stringprep Profile for Internationalized Domain Names (IDN)P. Hoffman, M. Blanchet · obsoleted by RFC 5891 | Proposed Standard | March 2003 |
| 3629 | UTF-8, a transformation format of ISO 10646F. Yergeau | Internet Standard | November 2003 |
| 4422 | Simple Authentication and Security Layer (SASL)A. Melnikov, Ed., K. Zeilenga, Ed. | Proposed Standard | June 2006 |
| 4510 | Lightweight Directory Access Protocol (LDAP): Technical Specification Road MapK. Zeilenga, Ed. | Proposed Standard | June 2006 |
| 4690 | Review and Recommendations for Internationalized Domain Names (IDNs)J. Klensin, P. Faltstrom, C. Karp, IAB | Informational | September 2006 |
| 5198 | Unicode Format for Network InterchangeJ. Klensin, M. Padlipsky | Proposed Standard | March 2008 |
| 5226 | Guidelines for Writing an IANA Considerations Section in RFCsT. Narten, H. Alvestrand · obsoleted by RFC 8126 | Best Current Practice | May 2008 |
| 5234 | Augmented BNF for Syntax Specifications: ABNFD. Crocker, Ed., P. Overell | Internet Standard | January 2008 |
| 5246 | The Transport Layer Security (TLS) Protocol Version 1.2T. Dierks, E. Rescorla · obsoleted by RFC 8446, RFC 9846 | Proposed Standard | August 2008 |
| 5741 | RFC Streams, Headers, and BoilerplatesL. Daigle, Ed., O. Kolkman, Ed., IAB · obsoleted by RFC 7841 | Informational | December 2009 |
| 5890 | Internationalized Domain Names for Applications (IDNA): Definitions and Document FrameworkJ. Klensin | Proposed Standard | August 2010 |
| 5891 | Internationalized Domain Names in Applications (IDNA): ProtocolJ. Klensin | Proposed Standard | August 2010 |
| 5892 | The Unicode Code Points and Internationalized Domain Names for Applications (IDNA)P. Faltstrom, Ed. | Proposed Standard | August 2010 |
| 5893 | Right-to-Left Scripts for Internationalized Domain Names for Applications (IDNA)H. Alvestrand, Ed., C. Karp | Proposed Standard | August 2010 |
| 5894 | Internationalized Domain Names for Applications (IDNA): Background, Explanation, and RationaleJ. Klensin | Informational | August 2010 |
| 5895 | Mapping Characters for Internationalized Domain Names in Applications (IDNA) 2008P. Resnick, P. Hoffman | Informational | September 2010 |
| 6365 | Terminology Used in Internationalization in the IETFP. Hoffman, J. Klensin | Best Current Practice | September 2011 |
| 6452 | The Unicode Code Points and Internationalized Domain Names for Applications (IDNA) - Unicode 6.0P. Faltstrom, Ed., P. Hoffman, Ed. | Proposed Standard | November 2011 |
| 6885 | Stringprep Revision and Problem Statement for the Preparation and Comparison of Internationalized Strings (PRECIS)M. Blanchet, A. Sullivan | Informational | March 2013 |
| 6943 | Issues in Identifier Comparison for Security PurposesD. Thaler, Ed. | Informational | May 2013 |