| 2119 | Key words for use in RFCs to Indicate Requirement LevelsS. Bradner | Best Current Practice | March 1997 |
| 2198 | RTP Payload for Redundant Audio DataC. Perkins, I. Kouvelas, O. Hodson, V. Hardman, M. Handley, J.C. Bolot, A. Vega-Garcia, S. Fosse-Parisis | Proposed Standard | September 1997 |
| 3261 | SIP: Session Initiation ProtocolJ. Rosenberg, H. Schulzrinne, G. Camarillo, A. Johnston, J. Peterson, R. Sparks, M. Handley, E. Schooler | Proposed Standard | July 2002 |
| 3263 | Session Initiation Protocol (SIP): Locating SIP ServersJ. Rosenberg, H. Schulzrinne | Proposed Standard | July 2002 |
| 3365 | Strong Security Requirements for Internet Engineering Task Force Standard ProtocolsJ. Schiller | Best Current Practice | August 2002 |
| 3455 | Private Header (P-Header) Extensions to the Session Initiation Protocol (SIP) for the 3rd-Generation Partnership Project (3GPP)M. Garcia-Martin, E. Henrikson, D. Mills · obsoleted by RFC 7315 | Informational | January 2003 |
| 3466 | A Model for Content Internetworking (CDI)M. Day, B. Cain, G. Tomlinson, P. Rzewski · obsoleted by RFC 7336 | Informational | March 2003 |
| 3550 | RTP: A Transport Protocol for Real-Time ApplicationsH. Schulzrinne, S. Casner, R. Frederick, V. Jacobson | Internet Standard | July 2003 |
| 3568 | Known Content Network (CN) Request-Routing MechanismsA. Barbir, B. Cain, R. Nair, O. Spatscheck | Informational | July 2003 |
| 3570 | Content Internetworking (CDI) ScenariosP. Rzewski, M. Day, D. Gilletti · obsoleted by RFC 6770 | Informational | July 2003 |
| 3611 | RTP Control Protocol Extended Reports (RTCP XR)T. Friedman, Ed., R. Caceres, Ed., A. Clark, Ed. | Proposed Standard | November 2003 |
| 3702 | Authentication, Authorization, and Accounting Requirements for the Session Initiation Protocol (SIP)J. Loughney, G. Camarillo | Informational | February 2004 |
| 3711 | The Secure Real-time Transport Protocol (SRTP)M. Baugher, D. McGrew, M. Naslund, E. Carrara, K. Norrman | Proposed Standard | March 2004 |
| 3824 | Using E.164 numbers with the Session Initiation Protocol (SIP)J. Peterson, H. Liu, J. Yu, B. Campbell | Informational | June 2004 |
| 3863 | Presence Information Data Format (PIDF)H. Sugano, S. Fujimoto, G. Klyne, A. Bateman, W. Carr, J. Peterson | Proposed Standard | August 2004 |
| 3966 | The tel URI for Telephone NumbersH. Schulzrinne | Proposed Standard | December 2004 |
| 3986 | Uniform Resource Identifier (URI): Generic SyntaxT. Berners-Lee, R. Fielding, L. Masinter | Internet Standard | January 2005 |
| 4347 | Datagram Transport Layer SecurityE. Rescorla, N. Modadugu · obsoleted by RFC 6347 | Historic | April 2006 |
| 4474 | Enhancements for Authenticated Identity Management in the Session Initiation Protocol (SIP)J. Peterson, C. Jennings · obsoleted by RFC 8224 | Proposed Standard | August 2006 |
| 4566 | SDP: Session Description ProtocolM. Handley, V. Jacobson, C. Perkins · obsoleted by RFC 8866 | Proposed Standard | July 2006 |
| 4571 | Framing Real-time Transport Protocol (RTP) and RTP Control Protocol (RTCP) Packets over Connection-Oriented TransportJ. Lazzaro | Proposed Standard | July 2006 |
| 4572 | Connection-Oriented Media Transport over the Transport Layer Security (TLS) Protocol in the Session Description Protocol (SDP)J. Lennox · obsoleted by RFC 8122 | Proposed Standard | July 2006 |
| 4786 | Operation of Anycast ServicesJ. Abley, K. Lindqvist | Best Current Practice | December 2006 |
| 4916 | Connected Identity in the Session Initiation Protocol (SIP)J. Elwell | Proposed Standard | June 2007 |
| 4975 | The Message Session Relay Protocol (MSRP)B. Campbell, Ed., R. Mahy, Ed., C. Jennings, Ed. | Proposed Standard | September 2007 |
| 5344 | Presence and Instant Messaging Peering Use CasesA. Houri, E. Aoki, S. Parameswar | Informational | October 2008 |
| 5411 | A Hitchhiker's Guide to the Session Initiation Protocol (SIP)J. Rosenberg | Informational | February 2009 |
| 5486 | Session Peering for Multimedia Interconnect (SPEERMINT) TerminologyD. Malas, Ed., D. Meyer, Ed. | Informational | March 2009 |
| 5503 | Private Session Initiation Protocol (SIP) Proxy-to-Proxy Extensions for Supporting the PacketCable Distributed Call Signaling ArchitectureF. Andreasen, B. McKibben, B. Marshall | Informational | March 2009 |
| 5630 | The Use of the SIPS URI Scheme in the Session Initiation Protocol (SIP)F. Audet | Proposed Standard | October 2009 |
| 5741 | RFC Streams, Headers, and BoilerplatesL. Daigle, Ed., O. Kolkman, Ed., IAB · obsoleted by RFC 7841 | Informational | December 2009 |
| 5763 | Framework for Establishing a Secure Real-time Transport Protocol (SRTP) Security Context Using Datagram Transport Layer Security (DTLS)J. Fischl, H. Tschofenig, E. Rescorla | Proposed Standard | May 2010 |
| 5764 | Datagram Transport Layer Security (DTLS) Extension to Establish Keys for the Secure Real-time Transport Protocol (SRTP)D. McGrew, E. Rescorla | Proposed Standard | May 2010 |
| 5923 | Connection Reuse in the Session Initiation Protocol (SIP)V. Gurbani, Ed., R. Mahy, B. Tate | Proposed Standard | June 2010 |
| 6076 | Basic Telephony SIP End-to-End Performance MetricsD. Malas, A. Morton | Proposed Standard | January 2011 |
| 6120 | Extensible Messaging and Presence Protocol (XMPP): CoreP. Saint-Andre | Proposed Standard | March 2011 |