Discussion of existing sip: sip-implementors@cs.columbia.edu To Subscribe: sip-implementors-request@cs.columbia.edu In Body: subscribe Archive: http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors =======================================================================
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 specifying and developing proposed extensions that arise out of strong requirements. The SIP working group will concentrate on the specification of SIP and its extensions, and will not explore the use of SIP for specific environments or applications. It will, however respond to general-purpose requirements for changes to SIP provided by other working groups, including the SIPPING working group, when those requirements are within the scope and charter of SIP.
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 generally applicable, 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 and because MMUSIC is developing a successor to SDP which SIP will also use.
The group will work very closely with the (proposed) SIPPING WG, which is expected to analyze the requirements for application of SIP to several different tasks, and with the SIMPLE WG, which is using SIP for messaging and presence.
The group will also maintain open dialogues with the IP telephony (IPTEL) WG, whose Call Processing Language (CPL) relates to many features of SIP; will continue to consider the requirements and specifications previously established by the PSTN and Internet Internetworking (PINT) working group;: and will consider input from the Distributed Call Signaling (DCS) Group of the PacketCable Consortium for distributed telephony services, and from 3GPP, 3GPP2, and MWIF for third-generation wireless network requirements.
The specific deliverables of the group are:
1. bis: A draft standard version of SIP.
2. callcontrol: Completion of the SIP call control specifications, which enables multiparty services, such as transfer and bridged sessions.
3. callerpref: Completion of the SIP caller preferences extensions, which enables intelligent call routing services.
4. mib: Define a MIB for SIP nodes.
5. precon: Completion of the SIP extensions needed to assure satisfaction of external preconditions such as QoS establishment.
6. state: Completion of the SIP extensions needed to manage state within signaling, aka SIP "cookies".
7. priv: Completion of SIP extensions for security and privacy.
8. security: Assuring generally adequate security and privacy mechanisms within SIP.
9. provrel: Completion of the SIP extensions needed for reliability of provisional messages.
10. servfeat: Completion of the SIP extensions needed for negotiation ofserver features.
11. sesstimer: Completion of the SIP Session Timer extension.
12. events: Completion of the SIP Events extensions (Subscribe/Notify).
13. security: Requirements for Privacy and Security.
14. natfriend: Extensions for making SIP a NAT-friendly protocol.
Other deliverables may be agreed upon as extensions are proposed. New deliverables must be approved by the Transport Area Directors before inclusion on the agenda.
NOTE: milestones within the same month are shown in order of planned completion.
Done |    | Server Features Negotiation submitted to IESG |
Apr 01 |    | Complete IESG requested fixes to provrel and servfeat |
May 01 |    | Session Timer spec to IESG |
Jun 01 |    | Transfer spec to IESG |
Jun 01 |    | NAT-awareness extension on REGISTER submitted to IESG. |
Jul 01 |    | Caller preferences specification submitted to IESG |
Jul 01 |    | SIP Privacy and Security Requirements to IESG |
Jul 01 |    | SIP Privacy specification (from DCS) to IESG |
Sep 01 |    | MIB spec to IESG |
Sep 01 |    | Preconditions extensions (manyfolks) spec to IESG |
Sep 01 |    | SIP Events specification to IESG |
Dec 01 |    | Revised proposed standard version of SIP (2543bis) submitted to IESG |
Dec 01 |    | Review WG status (consider closing) and/or submit a future milestones plan to IESG |
Jan 02 |    | SIP over SCTP specification and applicability statement |
RFC | Status | Title |
RFC2976 | PS | The SIP INFO Method |