2.7.16 Session Initiation Protocol (sip)

NOTE: This charter is a snapshot of the 46th IETF Meeting in Washington, DC. It may now be out-of-date. Last Modified: 25-Oct-99


Jonathan Rosenberg <jdrosen@dynamicsoft.com>
Joerg Ott <jo@tzi.uni-bremen.de>
Dean Willis <dean.willis@wcom.com>

Transport Area Director(s):

Scott Bradner <sob@harvard.edu>
Vern Paxson <vern@aciri.org>

Transport Area Advisor:

Vern Paxson <vern@aciri.org>

Mailing Lists:

General Discussion:sip@lists.research.bell-labs.com
To Subscribe: sip-request@lists.research.bell-labs.com
In Body: subscribe
Archive: http://www.bell-labs.com/mailing-lists/sip

Description of Working Group:

The Session Initiation Protocol (SIP) working group is chartered to continue the development of SIP, currently specified as proposed standard RFC 2543. SIP is a text-based protocol, similar to HTTP and SMTP, for initiating interactive communication sessions between users. Such sessions include voice, video, chat, interactive games, and virtual reality. The main work of the group involves bringing SIP from proposed to draft standard, in addition to developing proposed extensions.

Throughout its work, the group will strive to maintain the basic model and architecture defined by SIP. In particular:

1. Services and features are provided end to end whenever possible.

2. Extensions and new features must be general purpose, and not applicable only to a specific set of session types.

3. Simplicity is key.

4. Reuse of existing IP protocols and architectures, and integrating with other IP applications, is crucial.

SIP was first developed within the Multiparty Multimedia Session Control (MMUSIC) working group, and the SIP working group will continue to maintain active communications with MMUSIC. This is particularly important since the main MIME type carried in SIP messages, the Session Description Protocol (SDP), specified in RFC 2327, is developed by MMUSIC. The group will also maintain open dialogues with the IP telephony (iptel) working group, whose Call Processing Language (CPL) relates to many features of SIP, and the PSTN and Internet Internetworking (pint) working group, whose specification is based on SIP; and will consider input from the Distributed Call Signaling Group (DCS) for distributed telephony services.

The specific deliverables of the group are:

1. A Draft Standard version of SIP.

2. Completion of the SIP call control specification, which enables multiparty services, such as transfer and bridged sessions.

3. Completion of the SIP caller preferences specification, which enables intelligent call routing services.

4. Completion of the SIP INFO method extension, used for carrying SIP session related information.

5. Completion of the "183 response" extension, to enable early session establishment.

Other deliverables may be agreed upon as extensions are proposed.

Goals and Milestones:

Dec 99


INFO Method extension submitted to IESG

Feb 00


Early session establishment extension submitted to IESG

Mar 00


Caller preferences specification submitted to IESG

May 00


Call control specification submitted to IESG

Jul 00


Draft standard version of SIP submitted to IESG

Jul 00


SIP MIB submitted to IESG


No Request For Comments

Current Meeting Report

None received.


None received.