| 793 | Transmission Control ProtocolJ. Postel · obsoleted by RFC 9293 | Internet Standard | September 1981 |
| 1034 | Domain names - concepts and facilitiesP. Mockapetris | Internet Standard | November 1987 |
| 1464 | Using the Domain Name System To Store Arbitrary String AttributesR. Rosenbaum | Experimental | May 1993 |
| 1939 | Post Office Protocol - Version 3J. Myers, M. Rose | Internet Standard | May 1996 |
| 2026 | The Internet Standards Process -- Revision 3S. Bradner | Best Current Practice | October 1996 |
| 2119 | Key words for use in RFCs to Indicate Requirement LevelsS. Bradner | Best Current Practice | March 1997 |
| 2142 | Mailbox Names for Common Services, Roles and FunctionsD. Crocker | Proposed Standard | May 1997 |
| 2222 | Simple Authentication and Security Layer (SASL)J. Myers · obsoleted by RFC 4422, RFC 4752 | Proposed Standard | October 1997 |
| 2244 | ACAP -- Application Configuration Access ProtocolC. Newman, J. G. Myers | Proposed Standard | November 1997 |
| 2277 | IETF Policy on Character Sets and LanguagesH. Alvestrand | Best Current Practice | January 1998 |
| 2560 | X.509 Internet Public Key Infrastructure Online Certificate Status Protocol - OCSPM. Myers, R. Ankney, A. Malpani, S. Galperin, C. Adams · obsoleted by RFC 6960 | Proposed Standard | June 1999 |
| 2595 | Using TLS with IMAP, POP3 and ACAPC. Newman | Proposed Standard | June 1999 |
| 2616 | Hypertext Transfer Protocol -- HTTP/1.1R. Fielding, J. Gettys, J. Mogul, H. Frystyk, L. Masinter, P. Leach, T. Berners-Lee · obsoleted by RFC 7230, RFC 7231, RFC 7232, RFC 7233, RFC 7234, RFC 7235 | Draft Standard | June 1999 |
| 2743 | Generic Security Service Application Program Interface Version 2, Update 1J. Linn | Proposed Standard | January 2000 |
| 2779 | Instant Messaging / Presence Protocol RequirementsM. Day, S. Aggarwal, G. Mohr, J. Vincent | Informational | February 2000 |
| 2782 | A DNS RR for specifying the location of services (DNS SRV)A. Gulbrandsen, P. Vixie, L. Esibov | Proposed Standard | February 2000 |
| 2810 | Internet Relay Chat: ArchitectureC. Kalt | Informational | April 2000 |
| 2831 | Using Digest Authentication as a SASL MechanismP. Leach, C. Newman · obsoleted by RFC 6331 | Historic | May 2000 |
| 3023 | XML Media TypesM. Murata, S. St. Laurent, D. Kohn · obsoleted by RFC 7303 | Proposed Standard | January 2001 |
| 3061 | A URN Namespace of Object IdentifiersM. Mealling | Informational | February 2001 |
| 3365 | Strong Security Requirements for Internet Engineering Task Force Standard ProtocolsJ. Schiller | Best Current Practice | August 2002 |
| 3447 | Public-Key Cryptography Standards (PKCS) #1: RSA Cryptography Specifications Version 2.1J. Jonsson, B. Kaliski · obsoleted by RFC 8017 | Informational | February 2003 |
| 3470 | Guidelines for the Use of Extensible Markup Language (XML) within IETF ProtocolsS. Hollenbeck, M. Rose, L. Masinter | Best Current Practice | January 2003 |
| 3501 | INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1M. Crispin · obsoleted by RFC 9051 | Proposed Standard | March 2003 |
| 3552 | Guidelines for Writing RFC Text on Security ConsiderationsE. Rescorla, B. Korver | Best Current Practice | July 2003 |
| 3629 | UTF-8, a transformation format of ISO 10646F. Yergeau | Internet Standard | November 2003 |
| 3688 | The IETF XML RegistryM. Mealling | Best Current Practice | January 2004 |
| 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 |
| 3927 | Dynamic Configuration of IPv4 Link-Local AddressesS. Cheshire, B. Aboba, E. Guttman | Proposed Standard | May 2005 |
| 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 |
| 4033 | DNS Security Introduction and RequirementsR. Arends, R. Austein, M. Larson, D. Massey, S. Rose | Proposed Standard | March 2005 |
| 4086 | Randomness Requirements for SecurityD. Eastlake 3rd, J. Schiller, S. Crocker | Best Current Practice | June 2005 |
| 4122 | A Universally Unique IDentifier (UUID) URN NamespaceP. Leach, M. Mealling, R. Salz · obsoleted by RFC 9562 | Proposed Standard | July 2005 |
| 4270 | Attacks on Cryptographic Hashes in Internet ProtocolsP. Hoffman, B. Schneier | Informational | December 2005 |
| 4422 | Simple Authentication and Security Layer (SASL)A. Melnikov, Ed., K. Zeilenga, Ed. | Proposed Standard | June 2006 |
| 4505 | Anonymous Simple Authentication and Security Layer (SASL) MechanismK. Zeilenga | Proposed Standard | June 2006 |
| 4510 | Lightweight Directory Access Protocol (LDAP): Technical Specification Road MapK. Zeilenga, Ed. | Proposed Standard | June 2006 |
| 4616 | The PLAIN Simple Authentication and Security Layer (SASL) MechanismK. Zeilenga, Ed. | Proposed Standard | August 2006 |
| 4647 | Matching of Language TagsA. Phillips, Ed., M. Davis, Ed. | Best Current Practice | September 2006 |
| 4648 | The Base16, Base32, and Base64 Data EncodingsS. Josefsson | Proposed Standard | October 2006 |
| 4732 | Internet Denial-of-Service ConsiderationsM. Handley, Ed., E. Rescorla, Ed., IAB | Informational | December 2006 |
| 4949 | Internet Security Glossary, Version 2R. Shirey | Informational | August 2007 |
| 4962 | Guidance for Authentication, Authorization, and Accounting (AAA) Key ManagementR. Housley, B. Aboba | Best Current Practice | July 2007 |
| 4985 | Internet X.509 Public Key Infrastructure Subject Alternative Name for Expression of Service NameS. Santesson | Proposed Standard | August 2007 |
| 5056 | On the Use of Channel Bindings to Secure ChannelsN. Williams | Proposed Standard | November 2007 |
| 5077 | Transport Layer Security (TLS) Session Resumption without Server-Side StateJ. Salowey, H. Zhou, P. Eronen, H. Tschofenig · obsoleted by RFC 8446, RFC 9846 | Proposed Standard | January 2008 |
| 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 |
| 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 |
| 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 |
| 5321 | Simple Mail Transfer ProtocolJ. Klensin | Draft Standard | October 2008 |
| 5598 | Internet Mail ArchitectureD. Crocker | Informational | July 2009 |
| 5646 | Tags for Identifying LanguagesA. Phillips, Ed., M. Davis, Ed. | Best Current Practice | September 2009 |
| 5657 | Guidance on Interoperation and Implementation Reports for Advancement to Draft StandardL. Dusseault, R. Sparks | Best Current Practice | September 2009 |
| 5741 | RFC Streams, Headers, and BoilerplatesL. Daigle, Ed., O. Kolkman, Ed., IAB · obsoleted by RFC 7841 | Informational | December 2009 |
| 5746 | Transport Layer Security (TLS) Renegotiation Indication ExtensionE. Rescorla, M. Ray, S. Dispensa, N. Oskov | Proposed Standard | February 2010 |
| 5802 | Salted Challenge Response Authentication Mechanism (SCRAM) SASL and GSS-API MechanismsC. Newman, A. Menon-Sen, A. Melnikov, N. Williams | Proposed Standard | July 2010 |
| 5929 | Channel Bindings for TLSJ. Altman, N. Williams, L. Zhu | Proposed Standard | July 2010 |
| 5952 | A Recommendation for IPv6 Address Text RepresentationS. Kawamura, M. Kawashima | Proposed Standard | August 2010 |
| 6066 | Transport Layer Security (TLS) Extensions: Extension DefinitionsD. Eastlake 3rd | Proposed Standard | January 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 |
| 6125 | Representation and Verification of Domain-Based Application Service Identity within Internet Public Key Infrastructure Using X.509 (PKIX) Certificates in the Context of Transport Layer Security (TLS)P. Saint-Andre, J. Hodges · obsoleted by RFC 9525 | Proposed Standard | March 2011 |
| 6176 | Prohibiting Secure Sockets Layer (SSL) Version 2.0S. Turner, T. Polk | Proposed Standard | March 2011 |