Datagram Congestion Control Protocol (dccp) ------------------------------------------- Charter Last Modified: 2007-10-05 Current Status: Active Working Group Chair(s): Thomas Phelan Gorry Fairhurst Transport Area Director(s): Magnus Westerlund Lars Eggert Transport Area Advisor: Lars Eggert Mailing Lists: General Discussion:dccp@ietf.org To Subscribe: dccp-request@ietf.org In Body: (un)subscribe Archive: http://www.ietf.org/mail-archive/web/dccp/index.html Description of Working Group: The Datagram Control Protocol working group is chartered to develop and standardize the Datagram Congestion Control Protocol (DCCP). DCCP is a minimal general purpose transport-layer protocol providing only two core functions: - the establishment, maintenance and teardown of an unreliable packet flow. - congestion control of that packet flow. Within the constraints of providing these core functions, DCCP aims to be a general purpose protocol, minimizing the overhead of packet header size or end-node processing as much as possible. Therefore, DCCP is as simple as possible, and as far as reasonably possible, it should avoid providing higher-level transport functionality. DCCP will provide a congestion-controlled, unreliable packet stream, without TCP's reliability or in-order delivery semantics. Additional unicast, flow-based application functionality can be layered over DCCP. SCOPE Drafts for DCCP, and several associated congestion control IDs, already exist. The first task before the working group will be an abbreviated functional requirement validation of those drafts. There are two possible outcomes: 1) The current DCCP draft is declared suitable for further work, with some areas listed for possible extension. 2) The current DCCP draft is declared unsuitable for further work, and more formal functional requirement exploration begins. Prior to the final development of the protocol, the working group will investigate areas of functionality that should be integrated into DCCP because they are difficult or impossible to layer above it. These areas include security and multi-homing/mobility, at a minimum. The protocol will be for both IPv4 and IPv6. It will not encompass multicast. It is strictly a unicast transport. For security, the working group will endeavor to ensure that DCCP incorporates good non-cryptographic mechanisms that make it resistant to denial-of-service attacks on DCCP connections and DCCP servers. A related topic that will be explored is whether DCCP can be a candidate to replace UDP in the transport of security management protocols such as IKE and JFK. The working group will also investigate DCCP's relationship with RTP (the Real-time Transport Protocol). Once the DCCP specification has stabilized, the WG will produce a document providing guidance to potential users of DCCP. The precise form of this document will be determined by WG discussion, but it might include example APIs, an applicability statement, or other forms of guidance about appropriate usage of DCCP. Goals and Milestones: Done Publish summary of required protocol functions/requirements Done Decision to build on proposed DCCP protocol, alternate protocol, or quit and go home Done Detailed review of spec and CCIDs Done Public design review at IETF meeting Done Working group last call for spec and CCIDs Done Submit DCCP spec for IESG/IETF review to be Proposed Standard Done Submit DCCP CCIDs for IESG/IETF review to be Proposed Standard Done Complete WGLC draft-ietf-dccp-problem-xx as Informational Done Complete WGLC draft-ietf-dccp-tfrc-voip as Experimental Done Complete WGLC 'RTP over DCCP' as PS Jul 2007 Complete WGLC 'DTLS over DCCP' as PS Oct 2007 Complete WGLC draft-ietf-dccp-tfrc-faster-restart as Experimental Oct 2007 Complete WGLC for updated TFRC (rfc3448bis) as PS Dec 2007 Complete WGLC draft-ietf-dccp-tfrc-media as Informational Dec 2007 Complete WGLC for updated Service Codes as PS Jun 2008 Complete WGLC draft-ietf-dccp-ccid4 as Experimental Dec 2008 Complete WGLC draft-ietf-dccp-user-guide as Informational Internet-Drafts: Posted Revised I-D Title ------ ------- -------------------------------------------- Jul 2005 Nov 2007 Faster Restart for TCP Friendly Rate Control (TFRC) Jul 2006 Jun 2007 RTP and the Datagram Congestion Control Protocol (DCCP) Oct 2006 Jan 2008 TCP Friendly Rate Control (TFRC): Protocol Specification May 2007 Feb 2008 Datagram Transport Layer Security (DTLS) over the Datagram Congestion Control Protocol (DCCP) Jun 2007 Nov 2007 The DCCP Service Code Oct 2007 Nov 2007 Profile for Datagram Congestion Control Protocol (DCCP) Congestion ID 4: TCP-Friendly Rate Control for Small Packets (TFRC-SP) Request For Comments: RFC Stat Published Title ------- -- ----------- ------------------------------------ RFC4336 I Mar 2006 Problem Statement for the Datagram Congestion Control Protocol (DCCP) RFC4340 PS Mar 2006 Datagram Congestion Control Protocol (DCCP) RFC4341 PS Mar 2006 Profile for Datagram Congestion Control Protocol (DCCP) Congestion Control ID 2: TCP-like Congestion Control RFC4342 PS Apr 2006 Profile for Datagram Congestion Control Protocol (DCCP) Congestion Control ID 3: TCP-Friendly Rate Control (TFRC) RFC4828 E Apr 2007 TCP Friendly Rate Control (TFRC): the Small-Packet (SP) Variant