| 1035 | Domain names - implementation and specificationP. Mockapetris | Internet Standard | November 1987 |
| 1918 | Address Allocation for Private InternetsY. Rekhter, B. Moskowitz, D. Karrenberg, G. J. de Groot, E. Lear | Best Current Practice | February 1996 |
| 1939 | Post Office Protocol - Version 3J. Myers, M. Rose | Internet Standard | May 1996 |
| 3261 | SIP: Session Initiation ProtocolJ. Rosenberg, H. Schulzrinne, G. Camarillo, A. Johnston, J. Peterson, R. Sparks, M. Handley, E. Schooler | Proposed Standard | July 2002 |
| 3365 | Strong Security Requirements for Internet Engineering Task Force Standard ProtocolsJ. Schiller | Best Current Practice | August 2002 |
| 3501 | INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1M. Crispin · obsoleted by RFC 9051 | Proposed Standard | March 2003 |
| 4033 | DNS Security Introduction and RequirementsR. Arends, R. Austein, M. Larson, D. Massey, S. Rose | Proposed Standard | March 2005 |
| 4303 | IP Encapsulating Security Payload (ESP)S. Kent | Proposed Standard | December 2005 |
| 4949 | Internet Security Glossary, Version 2R. Shirey | Informational | August 2007 |
| 5246 | The Transport Layer Security (TLS) Protocol Version 1.2T. Dierks, E. Rescorla · obsoleted by RFC 8446, RFC 9846 | Proposed Standard | August 2008 |
| 5321 | Simple Mail Transfer ProtocolJ. Klensin | Draft Standard | October 2008 |
| 5741 | RFC Streams, Headers, and BoilerplatesL. Daigle, Ed., O. Kolkman, Ed., IAB · obsoleted by RFC 7841 | Informational | December 2009 |
| 6962 | Certificate TransparencyB. Laurie, A. Langley, E. Kasper · obsoleted by RFC 9162 | Experimental | June 2013 |
| 6973 | Privacy Considerations for Internet ProtocolsA. Cooper, H. Tschofenig, B. Aboba, J. Peterson, J. Morris, M. Hansen, R. Smith | Informational | July 2013 |
| 7011 | Specification of the IP Flow Information Export (IPFIX) Protocol for the Exchange of Flow InformationB. Claise, Ed., B. Trammell, Ed., P. Aitken | Internet Standard | September 2013 |
| 7258 | Pervasive Monitoring Is an AttackS. Farrell, H. Tschofenig | Best Current Practice | May 2014 |