Re: [Q] Error on FTP flow

[Fernando Cela Diaz <fcela@ce.chalmers.se>]

You are right, it works perfectly. It was my fault: I didn't notice I had 
defined the TWO TCPSink's, and traceapp was connected to the wrong one.

Thanks,

/FCD
 

On Thu, 29 Jul 1999, yangh wrote:

> Hi,
> > 
> > Now, it should work. The bad new is that the bytes_ variable inside
> > traceapp is not recording anything, at least in the examples I have
> > tested... 
> > 
> > Any idea? (I hope any NS guru is reading this ;-)


> I tried that code before. It DID record something. I believe that codes
> work.
> 
> Best Regards
> 
> Yang


















> > On Thu, 29 Jul 1999, HoKun Chung wrote:
> > 
> > > Dear sir.
> > > 
> > > I am a graduate student in korea. 
> > > I want  to get the sender/receiver's throughtput for the FTP application 
> > > over TCP agent, without trace file.
> > > 
> > > Luckily, I found the source.
> > > http://www-mash.cs.berkeley.edu/dist/archive/ns-users/9904/0200.html
> > > http://www-mash.cs.berkeley.edu/dist/archive/ns-users/9904/0116.html
> > >  
> > > but, I have a some problem. It occurs error. error message is 
> > > 
> > >     can't read "traceapp" : no such variable 
> > >     while executing "$ns at 0.1 "$traceapp start"
> > > 
> > > I can't solve this problem... Please, help me..
> > > 
> > > It is partical code for getting the throuthput of FTP.
> > > -----------------------------------------------------------------------------------------------------
> > > ......
> > > set n0 [$ns node]
> > > set n1 [$ns node]
> > > ......
> > > set tcp0 [new Agent/TCP]
> > > $ns attach-agent $n0 $tcp0
> > > 
> > > Class TraceApp  -superclass Application    # subclass created....
> > > 
> > > TraceApp instproc init {args} {
> > >  $self set bytes_ 0
> > >  eval $self next $args
> > > }
> > > 
> > > TraceApp instproc recv {byte} {
> > >  $self instvar bytes_
> > >  set bytes_ [expr $bytes_ + $byte]
> > >  return $bytes_
> > > }
> > > 
> > > set sink1 [new Agent/TCPSink]
> > > TraceApp traceapp
> > > traceapp attach-agent $sink1
> > > $ns attach-agent $n1 $sink1
> > > 
> > > set ftp0 [new Application/FTP]  
> > > $ftp0 attach-agent $tcp0
> > > 
> > > $ns connect $tcp0 $sink1
> > > 
> > > $ns at 0.1 "$traceapp start"                # error occurs .... ------------------
> > > $ns at 0.2 "$ftp0 start"
> > > $ns at 1.0 "$ftp0 stop"
> > > #puts "Traffic volumn = [$traceapp set bytes_]"
> > > $ns at 1.1 "finish"
> > > ...
> > > 
> > > Please, Help me....
> > > 
> > 
> > 
> > 
> > 
> 
>