Re: [ns] Ask for tcp sample ?

[Ishan Mandrekar <ishan@io.ece.drexel.edu>]

I believe u have to configure a traffic source (CBR/Expoo/Pareto) on top
of the TCP agent. Also try using TCPSink instead of Null agent to sink the
traffic.
Add this piece (with appropriate changes) to see if it works..

set cbr2 [new Application/Traffic/CBR]
$cbr2 attach-agent $tcp2
$cbr2 set packetSize_ 500
$cbr2 set interval_ 10ms

# Create a traffic sink in node n5
set null5 [new Agent/TCPSink]
$ns attach-agent $n5 $null5

Hope this helps!!
-Ishan.

On Tue, 25 Apr 2000, Jean-Louis Sacre wrote:

> hello everybody,
> 
> 
> I am a new user and I would like to create a TCP Agent.
> I have error when I try to create a new agent.
> 
> Can somebody help me to explain what is wrong and how to understand the
> error messages ?
> 
> Thanks
> 
> 
> Jean-Louis
> 
> 
> 
> Here is the script I use :
> 
> #Create a simulator object
> set ns [new Simulator]
> 
> #Open the nam trace file
> set nf [open out.nam w]
> $ns namtrace-all $nf
> 
> #Define a 'finish' procedure
> proc finish {} {
>         global ns nf
>         $ns flush-trace
>  #Close the trace file
>         close $nf
>  #Execute nam on the trace file
>         exec nam out.nam &
>         exit 0
> }
> 
> #Create two nodes
> set n0 [$ns node]
> set n1 [$ns node]
> 
> #Create a duplex link between the nodes
> $ns duplex-link $n0 $n1 1Mb 10ms DropTail
> 
> #Create a CBR agent and attach it to node n0
> set cbr0 [new Agent/TCP]
> $ns attach-agent $n0 $cbr0
> #$cbr0 set packetSize_ 500
> #$cbr0 set interval_ 0.005
> 
> #Create a Null agent (a traffic sink) and attach it to node n1
> set null0 [new Agent/Null]
> $ns attach-agent $n1 $null0
> 
> #Connect the traffic source with the traffic sink
> $ns connect $cbr0 $null0
> 
> #Schedule events for the CBR agent
> $ns at 0.5 "$cbr0 start"
> $ns at 4.5 "$cbr0 stop"
> #Call the finish procedure after 5 seconds of simulation time
> $ns at 5.0 "finish"
> 
> #Run the simulation
> $ns run
> 
> 
> And here are the errors I received :
> 
> ns: _o34 start:
>     (_o34 cmd line 1)
>     invoked from within
> "_o34 cmd start"
>     invoked from within
> "catch "$self cmd $args" ret"
>     (procedure "_o34" line 2)
>     (SplitObject unknown line 2)
>     invoked from within
> "_o34 start"
> 
>