tphelan at sonusnet dot com
DCCP - Datagram Congestion Control
DCCP is a new transport protocol being developed by the IETF to provide
a connection-oriented, congestion controlled, unreliable transport
service. Most applications that require an unreliable transport
currently use UDP and ignore congestion issues, causing concerns about
congestion collapse in the general Internet if these applications
(especially VoIP) get too popular. DCCP is meant to give these
applications an opportunity to become good 'Net citizens without
forcing them to individually tackle the difficult problems of
developing congestion control mechanisms.
I am co-chair of the DCCP Working Group at the IETF.
My main interests are in using DCCP for two-way voice
applications. The following contributions are available here:
- DCCP-TP, a fresh-start implementation of DCCP optimized
Click here for the wiki with source code downloads,
documentation and discussion forum.
- DCCP-NAT, an alternative encapsulation for DCCP that supports
- DCCP, TFRC & Open
Problems in Congestion Control for Media Applications
-- Presentation given at ICCRG in Marina Del Ray, CA, 13-Feb-2007
- DTLS over DCCP
- Requirements for a CCID for Interactive
Applications - Presentation given at IETF64 in Vancouver.
- Strategies for Streaming Media Applications Using TCP-Friendly Rate Control,
draft-ietf-dccp-tfrc-media-02.txt - At IETF62
in Minneapolis, we decided to split the User Guide into two documents, one for streaming
media issues and one for API issues. This is the streaming media document.
- TFRC with Self-Limiting Sources,
tfrc-self-limit.pdf - This paper describes the results
of a simulation study on how fairly self-limited TFRC sources (such as streaming
media) compete with TCP-based applications for scarce bandwidth (updated on
- tfrc-self-limit.tgz - Simulation
scripts, raw results and ns source code modifictions used for the simulation
(updated and missing files added on 20-Oct-2004. Note: rebuild ns from scratch
after adding these files).
- Washington IETF Presentation
- Media Friendly Rate Control (MFRC),
draft-phelan-mfrc-00.txt - This draft details
some ideas for a congestion control mechanism that is more sensitive to the needs of
streaming media than TFRC. This work is at a very early stage. The intent
here is to gain feedback and hopefully stimulate some new thinking.
- DCCP User Guide,
- This draft expands the DCCP Media Guide into other application areas,
and is meant to be the general User Guide that the DCCP working group
charter calls for.
- -03 is a trivial update meant to keep the draft alive in the I-D
- -02 version:
- User Guide with marked diffs from -01 to -02:
- San Diego IETF User Guide Presentation
- -01 version: draft-ietf-user-guide-01.txt
- Seoul IETF User Guide Presentation - Presentation
given at IETF59 in Seoul on DCCP User Guide.  Note that this is not a tutorial, it just
covers current issues.
DCCP Media Guide, draft-phelan-dccp-media-00.txt
- This draft explores the issues surrounding using DCCP for streaming
media applications. An updated version has been subsumed into the
DCCP User Guide.
- This was an effort to define a reduced complexity version of DCCP,
more suitable for implementation in resource-starved environments such
as DSPs. This draft has been obsoleted by CCID 3-Thin (draft-ietf-dccp-ccid3-thin-00.txt)
from Eddie Kohler. Continuing work is focused on 3-Thin.
Other DCCP links: