RE: [ns] Trivial question about TCPSink

[Michael Welzl <michael@tk.uni-linz.ac.at>]

Hi,

I don't quite get the recvBytes(int bytes) method thing.
Anyway, I solved that problem by introducing a bound bytes_ variable
variable which I increased by numBytes numBytes line (2nd line (*), numBytes
= ... )in the recv method. Is there anything wrong with this?

Cheers,
Michael


(*) for more 2nd line, see http://www.rebirthbrassband.com/
;-)

> -----Original Message-----
> From: owner-ns-users@ISI.EDU
> [mailto:owner-ns-users@ISI.EDU]On Behalf Of
> Srihari Raghavan
> Sent: Friday, April 27, 2001 12:41 AM
> To: Lloyd Wood
> Cc: ns users
> Subject: RE: [ns] Trivial question about TCPSink
>
>
> Hi,
>   Thank you for your time. I noticed after my post that you
> had answered it
> in one of the previous postings. Sorry about that.
>   For others, in case one needs, here is the posting of the solution.
>   http://mash.cs.berkeley.edu/dist/archive/ns-users/0003/0069.html
>
> Thanks
> Srihari Raghavan
>
> -----Original Message-----
> From: Lloyd Wood [mailto:l.wood@eim.surrey.ac.uk]
> Sent: Thursday, April 26, 2001 6:17 PM
> To: Srihari Raghavan
> Cc: ns-users@ISI.EDU
> Subject: Re: [ns] Trivial question about TCPSink
>
>
> On Thu, 26 Apr 2001, Srihari Raghavan wrote:
>
> > I am using a variation of the traditional dumbbell shaped
> topology with
> > both UDP (CBR) sources and TCP (infinite FTP) sources. I am
> trying to mix
> > these two traffic in a common bottleneck link that has less
> capacity than
> > compared to the rate at which the sources generate traffic. When I
> increase
> > UDP traffic I expect TCP througphut over time to decrease
> due to the TCP
> > congestion control.
> >
> > The question is that I need to collect bandwidth (in Mbps) at the
> > TCPSink. With, Agent/LossMonitor sink for the UDP case, I
> use "bytes_" in
> > the oft-repeated "record" function to collect statistics.
> With TCPSink I
> do
> > not have a similar data member.
>
> You need to hack TCPSink's recv() function in the tcp-sink.cc file to
> record the data you want, after introducing your own bound variables.
> For the actual bytes received, numbytes in the tcp-sink file should
> probably be a bound variable - but isn't. (note that header overhead
> isn't counted, and doesn't exist anyway.)
>
> There's a pointer to a (very simple, because I'm lazy) hack on my ns
> webpage to record the rather different application-level throughput by
> adding a recvBytes() method. This should probably increment a bound
> variable called numbytesdelivered_ or somesuch.
>
> TCPSink is generally neglected IMO.
>
> L.
>
> > I tried using the TCP agent's "ndatabytes_", but it gives
> the sender's
> > view of the TCP bandwidth. What I need is the reciever's
> > (TCPSink's) view of TCP bandwidth recieved over time. Do I
> need to use
> > "acks" at the sender? Or is there any other way?
> >
> > Thank you for your time
> > /Srihari
> >
> >
>
> <L.Wood@surrey.ac.uk>PGP<http://www.ee.surrey.ac.uk/Personal/L.Wood/>
>