| 2119 | Key words for use in RFCs to Indicate Requirement LevelsS. Bradner | Best Current Practice | March 1997 |
| 2141 | URN SyntaxR. Moats · obsoleted by RFC 8141 | Proposed Standard | May 1997 |
| 2474 | Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 HeadersK. Nichols, S. Blake, F. Baker, D. Black | Proposed Standard | December 1998 |
| 2648 | A URN Namespace for IETF DocumentsR. Moats | Informational | August 1999 |
| 3023 | XML Media TypesM. Murata, S. St. Laurent, D. Kohn · obsoleted by RFC 7303 | Proposed Standard | January 2001 |
| 3261 | SIP: Session Initiation ProtocolJ. Rosenberg, H. Schulzrinne, G. Camarillo, A. Johnston, J. Peterson, R. Sparks, M. Handley, E. Schooler | Proposed Standard | July 2002 |
| 3264 | An Offer/Answer Model with Session Description Protocol (SDP)J. Rosenberg, H. Schulzrinne | Proposed Standard | July 2002 |
| 3470 | Guidelines for the Use of Extensible Markup Language (XML) within IETF ProtocolsS. Hollenbeck, M. Rose, L. Masinter | Best Current Practice | January 2003 |
| 3688 | The IETF XML RegistryM. Mealling | Best Current Practice | January 2004 |
| 4566 | SDP: Session Description ProtocolM. Handley, V. Jacobson, C. Perkins · obsoleted by RFC 8866 | Proposed Standard | July 2006 |
| 4574 | The Session Description Protocol (SDP) Label AttributeO. Levin, G. Camarillo | Proposed Standard | August 2006 |
| 4583 | Session Description Protocol (SDP) Format for Binary Floor Control Protocol (BFCP) StreamsG. Camarillo · obsoleted by RFC 8856 | Proposed Standard | November 2006 |
| 4629 | RTP Payload Format for ITU-T Rec. H.263 VideoJ. Ott, C. Bormann, G. Sullivan, S. Wenger, R. Even, Ed. | Proposed Standard | January 2007 |
| 4855 | Media Type Registration of RTP Payload FormatsS. Casner | Proposed Standard | February 2007 |
| 4856 | Media Type Registration of Payload Formats in the RTP Profile for Audio and Video ConferencesS. Casner | Proposed Standard | February 2007 |
| 4975 | The Message Session Relay Protocol (MSRP)B. Campbell, Ed., R. Mahy, Ed., C. Jennings, Ed. | Proposed Standard | September 2007 |
| 4976 | Relay Extensions for the Message Sessions Relay Protocol (MSRP)C. Jennings, R. Mahy, A. B. Roach | Proposed Standard | September 2007 |
| 5741 | RFC Streams, Headers, and BoilerplatesL. Daigle, Ed., O. Kolkman, Ed., IAB · obsoleted by RFC 7841 | Informational | December 2009 |
| 5766 | Traversal Using Relays around NAT (TURN): Relay Extensions to Session Traversal Utilities for NAT (STUN)R. Mahy, P. Matthews, J. Rosenberg · obsoleted by RFC 8656 | Proposed Standard | April 2010 |
| 6080 | A Framework for Session Initiation Protocol User Agent Profile DeliveryD. Petrie, S. Channabasappa, Ed. | Proposed Standard | March 2011 |
| 6794 | A Framework for Session Initiation Protocol (SIP) Session PoliciesV. Hilt, G. Camarillo, J. Rosenberg | Proposed Standard | December 2012 |
| 6795 | A Session Initiation Protocol (SIP) Event Package for Session-Specific PoliciesV. Hilt, G. Camarillo | Proposed Standard | December 2012 |