Session Initiation Protocol (SIP) Extension for Instant Messaging
RFC 3428
Document | Type |
RFC - Proposed Standard
(December 2002; Errata)
Updated by RFC 8591
Was draft-ietf-sip-message (sip WG)
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Authors | Henning Schulzrinne , Jonathan Rosenberg , Ben Campbell , David Gurle , Christian Huitema | ||
Last updated | 2015-10-14 | ||
Stream | Internent Engineering Task Force (IETF) | ||
Formats | plain text html pdf htmlized (tools) htmlized bibtex | ||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 3428 (Proposed Standard) | |
Action Holders |
(None)
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Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | Allison Mankin | ||
IESG note | Published 2002-12-06 | ||
Send notices to | <rohan@cisco.com> |
Network Working Group B. Campbell, Ed. Request for Comments: 3428 J. Rosenberg Category: Standards Track dynamicsoft H. Schulzrinne Columbia University C. Huitema D. Gurle Microsoft Corporation December 2002 Session Initiation Protocol (SIP) Extension for Instant Messaging Status of this Memo This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited. Copyright Notice Copyright (C) The Internet Society (2002). All Rights Reserved. Abstract Instant Messaging (IM) refers to the transfer of messages between users in near real-time. These messages are usually, but not required to be, short. IMs are often used in a conversational mode, that is, the transfer of messages back and forth is fast enough for participants to maintain an interactive conversation. This document proposes the MESSAGE method, an extension to the Session Initiation Protocol (SIP) that allows the transfer of Instant Messages. Since the MESSAGE request is an extension to SIP, it inherits all the request routing and security features of that protocol. MESSAGE requests carry the content in the form of MIME body parts. MESSAGE requests do not themselves initiate a SIP dialog; under normal usage each Instant Message stands alone, much like pager messages. MESSAGE requests may be sent in the context of a dialog initiated by some other SIP request. Campbell, et. al. Standards Track [Page 1] RFC 3428 SIP Message Extension December 2002 Terminology In this document, the key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY" and "OPTIONAL" are to be interpreted as described in BCP 14, RFC 2119 [6] and indicate requirement levels for compliant SIP implementations. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Scope of Applicability . . . . . . . . . . . . . . . . . . . 3 3. Overview of Operation . . . . . . . . . . . . . . . . . . . 4 4. UAC Processing . . . . . . . . . . . . . . . . . . . . . . . 5 5. Use of Instant Message URIs . . . . . . . . . . . . . . . . 6 6. Proxy Processing . . . . . . . . . . . . . . . . . . . . . . 6 7. UAS Processing . . . . . . . . . . . . . . . . . . . . . . . 7 8. Congestion Control . . . . . . . . . . . . . . . . . . . . . 8 9. Method Definition . . . . . . . . . . . . . . . . . . . . . 9 10. Example Messages . . . . . . . . . . . . . . . . . . . . . . 11 11. Security Considerations . . . . . . . . . . . . . . . . . . 13 11.1 Outbound authentication . . . . . . . . . . . . . . . . . . 13 11.2 SIPS URIs . . . . . . . . . . . . . . . . . . . . . . . . . 14 11.3 End-to-End Protection . . . . . . . . . . . . . . . . . . . 14 11.4 Replay Prevention . . . . . . . . . . . . . . . . . . . . . 14 11.5 Using message/cpim bodies . . . . . . . . . . . . . . . . . 15 12. IANA Considerations . . . . . . . . . . . . . . . . . . . . 15 13. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 15 14. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . 15 15. Normative References . . . . . . . . . . . . . . . . . . . . 16 16. Informational References . . . . . . . . . . . . . . . . . . 16 17. Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 17 18. Full Copyright Statement . . . . . . . . . . . . . . . . . . 18 1. Introduction Instant Messaging (IM) is defined as the exchange of content between a set of participants in near real time. Generally, the content is short text messages, although that need not be the case. Generally, the messages that are exchanged are not stored, but this also need not be the case. IM differs from email in common usage in that instant messages are usually grouped together into brief live conversations, consisting of numerous small messages sent back and forth. Instant messaging as a service has been in existence within intranets and IP networks for quite some time. Early implementations include zephyr [11], the UNIX talk application, and IRC. More recently, IMShow full document text