| 1034 | Domain names - concepts and facilitiesP. Mockapetris | Internet Standard | November 1987 |
| 1123 | Requirements for Internet Hosts - Application and SupportR. Braden, Ed. | Internet Standard | October 1989 |
| 1535 | A Security Problem and Proposed Correction With Widely Deployed DNS SoftwareE. Gavron | Informational | October 1993 |
| 2119 | Key words for use in RFCs to Indicate Requirement LevelsS. Bradner | Best Current Practice | March 1997 |
| 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 |
| 3629 | UTF-8, a transformation format of ISO 10646F. Yergeau | Internet Standard | November 2003 |
| 3920 | Extensible Messaging and Presence Protocol (XMPP): CoreP. Saint-Andre, Ed. · obsoleted by RFC 6120 | Proposed Standard | October 2004 |
| 3921 | Extensible Messaging and Presence Protocol (XMPP): Instant Messaging and PresenceP. Saint-Andre, Ed. · obsoleted by RFC 6121 | Proposed Standard | October 2004 |
| 3986 | Uniform Resource Identifier (URI): Generic SyntaxT. Berners-Lee, R. Fielding, L. Masinter | Internet Standard | January 2005 |
| 3987 | Internationalized Resource Identifiers (IRIs)M. Duerst, M. Suignard | Proposed Standard | January 2005 |
| 4013 | SASLprep: Stringprep Profile for User Names and PasswordsK. Zeilenga · obsoleted by RFC 7613 | Proposed Standard | March 2005 |
| 4422 | Simple Authentication and Security Layer (SASL)A. Melnikov, Ed., K. Zeilenga, Ed. | Proposed Standard | June 2006 |
| 5122 | Internationalized Resource Identifiers (IRIs) and Uniform Resource Identifiers (URIs) for the Extensible Messaging and Presence Protocol (XMPP)P. Saint-Andre | Proposed Standard | February 2008 |
| 5234 | Augmented BNF for Syntax Specifications: ABNFD. Crocker, Ed., P. Overell | Internet Standard | January 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 |
| 5892 | The Unicode Code Points and Internationalized Domain Names for Applications (IDNA)P. Faltstrom, Ed. | Proposed Standard | August 2010 |
| 5895 | Mapping Characters for Internationalized Domain Names in Applications (IDNA) 2008P. Resnick, P. Hoffman | Informational | September 2010 |
| 6120 | Extensible Messaging and Presence Protocol (XMPP): CoreP. Saint-Andre | Proposed Standard | March 2011 |
| 6121 | Extensible Messaging and Presence Protocol (XMPP): Instant Messaging and PresenceP. Saint-Andre | Proposed Standard | March 2011 |
| 6122 | Extensible Messaging and Presence Protocol (XMPP): Address FormatP. Saint-Andre · obsoleted by RFC 7622 | Proposed Standard | March 2011 |
| 6365 | Terminology Used in Internationalization in the IETFP. Hoffman, J. Klensin | Best Current Practice | September 2011 |
| 6874 | Representing IPv6 Zone Identifiers in Address Literals and Uniform Resource IdentifiersB. Carpenter, S. Cheshire, R. Hinden · obsoleted by RFC 9844 | Proposed Standard | February 2013 |
| 6885 | Stringprep Revision and Problem Statement for the Preparation and Comparison of Internationalized Strings (PRECIS)M. Blanchet, A. Sullivan | Informational | March 2013 |
| 7564 | PRECIS Framework: Preparation, Enforcement, and Comparison of Internationalized Strings in Application ProtocolsP. Saint-Andre, M. Blanchet · obsoleted by RFC 8264 | Proposed Standard | May 2015 |
| 7613 | Preparation, Enforcement, and Comparison of Internationalized Strings Representing Usernames and PasswordsP. Saint-Andre, A. Melnikov · obsoleted by RFC 8265 | Proposed Standard | August 2015 |