some quesition

Hi Najmeh,

See inline...

Tom P.

> -----Original Message-----
> From: dccp-bouncesietf.org [mailto:dccp-bouncesietf.org]
On Behalf
Of
> NAJMEH
> Sent: Saturday, February 11, 2006 5:18 AM
> To: dccpietf.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.

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

> 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".

> 
> I hope you can answer my question. I look forward to
your
> answer.
> Yours sincerely
> Najmeh Rezazadehkia

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

Ditto, for the status of the Linux implementation.

>
> Tom P.
>
> > -----Original Message-----
> > From: dccp-bouncesietf.org
[mailto:dccp-bouncesietf.org] On Behalf
> Of
> > NAJMEH
> > Sent: Saturday, February 11, 2006 5:18 AM
> > To: dccpietf.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


> > 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
dccpvger.kernel.org
mailing list, to subscribe to it just send a message with
"subscribe
dccp" on the
body of a message addressed to majordomovger.kernel.org.

- Arnaldo