[dccp] Re: some quesition

[Arnaldo Carvalho de Melo <arnaldo.melo at gmail.com>]

On 2/11/06, Phelan, Tom <tphelan at sonusnet.com> wrote:
> Hi Najmeh,
>
> See inline...

Ditto, for the status of the Linux implementation.

>
> Tom P.
>
> > -----Original Message-----
> > From: dccp-bounces at ietf.org [mailto:dccp-bounces at ietf.org] On Behalf
> Of
> > NAJMEH
> > Sent: Saturday, February 11, 2006 5:18 AM
> > To: dccp at ietf.org
> > Subject: [dccp] some quesition
> >
> > Hello
> > I am a student that study about DCCP protocol. I have some
> > question about it.
> > 1. If you can tell me about DCCP future?
> [Tom]
> The main specs for the protocol are in the RFC Editor's queue and should
> emerge "any day now".  Future work in the dccp group will deal with
> supplying more capabilities -- things like RTP over DCCP and TLS over
> DCCP.  We'll also be investigating new congestion control techniques (in
> cooperation with the iccrg (Internet Congestion Control Research Group)
> that handle some of the idiosyncrasies of specific applications, like
> interactive media streams.
>
> > 2. If there is other competes protocol? Allso with DCCP?
> [Tom]
> There's no other IETF protocol that directly provides the capabilities
> that DCCP does, as far as I know.
>
> > 3. If DCCP uses already somewhere today?
> [Tom]
> There are implementations available for Linux and NetBSD.  They are not
> completely up-to-date yet, but they do provide significant functionality
> and are being updated continuously.

Linux implementation has most of the bits in place, the 2.6.17 queue has
CCID2 (TCP-Like congestion control), feature negotiation work and
improvements on the ack vector code.

Please look at:

http://linux-net.osdl.org/index.php/DCCP
http://linux-net.osdl.org/index.php/TODO#DCCP

Where you'll find more information about current TODO list, patches
for apps, etc.

> > 4. If there is possible compensate completely UDP?
> [Tom]
> Sorry, can't understand this.

Compensate on what? on UDP lack of congestion control? yes 8-)

> > 5. What means "TCP-friendly"?
> [Tom]
> If a flow not using TCP congestion control will receive roughly equal
> throughput as a TCP flow operating in the same conditions, then that
> flow is said to be "TCP-Friendly".

Yes, try the latest released Linux kernel (2.6.15) and you'll be able to
test our CCID3 (TCP-Friendly)  implementation (that has a long lineage, FreeBSD,
Waikato (Linux already) then Linux mainstream).

Yes, its work in progress, so feel free to report bugs in the
dccp at vger.kernel.org
mailing list, to subscribe to it just send a message with "subscribe
dccp" on the
body of a message addressed to majordomo at vger.kernel.org.

- Arnaldo