| 9810 | Internet X.509 Public Key Infrastructure -- Certificate Management Protocol (CMP)H. Brockhaus, D. von Oheimb, M. Ounsworth, J. Gray | Proposed Standard | July 2025 |
| 9219 | S/MIME Signature Verification Extension to the JSON Meta Application Protocol (JMAP)A. Melnikov | Proposed Standard | April 2022 |
| 8551 | Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 4.0 Message SpecificationJ. Schaad, B. Ramsdell, S. Turner | Proposed Standard | April 2019 |
| 7681 | Email Exchange of Secondary School TranscriptsJ. Davin | Informational | October 2015 |
| 6109 | La Posta Elettronica Certificata - Italian Certified Electronic MailC. Petrucci, F. Gennai, A. Shahin, A. Vinciarelli | Informational | April 2011 |
| 6047 | iCalendar Message-Based Interoperability Protocol (iMIP)A. Melnikov, Ed. | Proposed Standard | December 2010 |
| 5751 | Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.2 Message SpecificationB. Ramsdell, S. Turner · obsoleted by RFC 8551 | Proposed Standard | January 2010 |
| 5402 | Compressed Data within an Internet Electronic Data Interchange (EDI) MessageT. Harding, Ed. | Informational | February 2010 |
| 5321 | Simple Mail Transfer ProtocolJ. Klensin | Draft Standard | October 2008 |
| 4871 | DomainKeys Identified Mail (DKIM) SignaturesE. Allman, J. Callas, M. Delany, M. Libbey, J. Fenton, M. Thomas · obsoleted by RFC 6376 | Proposed Standard | May 2007 |
| 4823 | FTP Transport for Secure Peer-to-Peer Business Data Interchange over the InternetT. Harding, R. Scott | Informational | April 2007 |
| 4662 | A Session Initiation Protocol (SIP) Event Notification Extension for Resource ListsA. B. Roach, B. Campbell, J. Rosenberg | Proposed Standard | August 2006 |
| 4450 | Getting Rid of the Cruft: Report from an Experiment in Identifying and Reclassifying Obsolete Standards DocumentsE. Lear, H. Alvestrand | Informational | March 2006 |
| 4210 | Internet X.509 Public Key Infrastructure Certificate Management Protocol (CMP)C. Adams, S. Farrell, T. Kause, T. Mononen · obsoleted by RFC 9810 | Proposed Standard | September 2005 |
| 4130 | MIME-Based Secure Peer-to-Peer Business Data Interchange Using HTTP, Applicability Statement 2 (AS2)D. Moberg, R. Drummond | Proposed Standard | July 2005 |
| 4021 | Registration of Mail and MIME Header FieldsG. Klyne, J. Palme | Proposed Standard | March 2005 |
| 3923 | End-to-End Signing and Object Encryption for the Extensible Messaging and Presence Protocol (XMPP)P. Saint-Andre | Proposed Standard | October 2004 |
| 3862 | Common Presence and Instant Messaging (CPIM): Message FormatG. Klyne, D. Atkins | Proposed Standard | August 2004 |
| 3851 | Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 3.1 Message SpecificationB. Ramsdell, Ed. · obsoleted by RFC 5751 | Proposed Standard | July 2004 |
| 3792 | Survey of IPv4 Addresses in Currently Deployed IETF Security Area Standards Track and Experimental DocumentsP. Nesser, II, A. Bergstrom, Ed. | Informational | June 2004 |
| 3631 | Security Mechanisms for the InternetS. Bellovin, Ed., J. Schiller, Ed., C. Kaufman, Ed. | Informational | December 2003 |
| 3459 | Critical Content Multi-purpose Internet Mail Extensions (MIME) ParameterE. Burger | Proposed Standard | January 2003 |
| 3335 | MIME-based Secure Peer-to-Peer Business Data Interchange over the InternetT. Harding, R. Drummond, C. Shih | Proposed Standard | September 2002 |
| 3261 | SIP: Session Initiation ProtocolJ. Rosenberg, H. Schulzrinne, G. Camarillo, A. Johnston, J. Peterson, R. Sparks, M. Handley, E. Schooler | Proposed Standard | July 2002 |
| 3199 | Request for Comments Summary RFC Numbers 3100-3199S. Ginoza | Informational | February 2003 |
| 3156 | MIME Security with OpenPGPM. Elkins, D. Del Torto, R. Levien, T. Roessler | Proposed Standard | August 2001 |
| 2975 | Introduction to Accounting ManagementB. Aboba, J. Arkko, D. Harrington | Informational | October 2000 |
| 2821 | Simple Mail Transfer ProtocolJ. Klensin, Ed. · obsoleted by RFC 5321 | Proposed Standard | April 2001 |
| 2798 | Definition of the inetOrgPerson LDAP Object ClassM. Smith | Informational | April 2000 |
| 2660 | The Secure HyperText Transfer ProtocolE. Rescorla, A. Schiffman | Historic | August 1999 |
| 2653 | CIP Transport ProtocolsJ. Allen, P. Leach, R. Hedberg | Proposed Standard | August 1999 |
| 2652 | MIME Object Definitions for the Common Indexing Protocol (CIP)J. Allen, M. Mealling | Proposed Standard | August 1999 |
| 2649 | An LDAP Control and Schema for Holding Operation SignaturesB. Greenblatt, P. Richard | Experimental | August 1999 |
| 2633 | S/MIME Version 3 Message SpecificationB. Ramsdell, Ed. · obsoleted by RFC 3851 | Proposed Standard | June 1999 |
| 2595 | Using TLS with IMAP, POP3 and ACAPC. Newman | Proposed Standard | June 1999 |
| 2510 | Internet X.509 Public Key Infrastructure Certificate Management ProtocolsC. Adams, S. Farrell · obsoleted by RFC 4210 | Proposed Standard | March 1999 |
| 2480 | Gateways and MIME Security MultipartsN. Freed | Proposed Standard | January 1999 |
| 2447 | iCalendar Message-Based Interoperability Protocol (iMIP)F. Dawson, S. Mansour, S. Silverberg · obsoleted by RFC 6047 | Proposed Standard | November 1998 |
| 2446 | iCalendar Transport-Independent Interoperability Protocol (iTIP) Scheduling Events, BusyTime, To-dos and Journal EntriesS. Silverberg, S. Mansour, F. Dawson, R. Hopson · obsoleted by RFC 5546 | Proposed Standard | November 1998 |
| 2442 | The Batch SMTP Media TypeN. Freed, D. Newman, J. Belissent, M. Hoy | Informational | November 1998 |
| 2316 | Report of the IAB Security Architecture WorkshopS. Bellovin | Informational | April 1998 |
| 2311 | S/MIME Version 2 Message SpecificationS. Dusse, P. Hoffman, B. Ramsdell, L. Lundblade, L. Repka | Historic | March 1998 |
| 2099 | Request for Comments Summary RFC Numbers 2000-2099J. Elliott | Informational | March 1997 |
| 2015 | MIME Security with Pretty Good Privacy (PGP)M. Elkins | Proposed Standard | October 1996 |
| 1848 | MIME Object Security ServicesS. Crocker, N. Freed, J. Galvin, S. Murphy | Historic | October 1995 |