Re: question on CBQ

[Massimo Pegorer - stage <pegorer@tvdsp2.vim.tlt.alcatel.it>]

1) you must insert also topclass:

	$cbqlink insert $topClass

2) fid is for agents, not traffic generators, so:

	$s1 set fid_ 1
		instead of
	$exp1 set fid_ 1
		and
	$s2 set fid_ 2
		instead of
	$exp2 set fid_ 2


Max.

> wuwei wrote:
> 
> Dear all,
> I just begin using the ns to simulate the CBQ and can't find the
> reason of errors in my script.Please give me some suggestions.
> Thanks in advance.
> 
> My script is as follows:
> 
> 
> #Create a simulator object
> 
> set ns [new Simulator]
> 
> #Open the nam trace file
> 
> set nf [open out.nam w]
> 
> $ns namtrace-all $nf
> 
> #Create 4 nodes
> 
> set n1 [$ns node]
> 
> set n2 [$ns node]
> 
> set n3 [$ns node]
> 
> set n4 [$ns node]
> 
> #Connect the nodes
> 
> $ns duplex-link $n1 $n3 10Mb 100ms DropTail
> 
> $ns duplex-link $n2 $n3 10Mb 100ms DropTail
> 
> $ns duplex-link $n3 $n4 1Mb 100ms CBQ
> 
> 
> 
> set cbqlink [$ns link $n3 $n4]
> 
> $ns duplex-link-op $n1 $n3 orient right-up
> 
> $ns duplex-link-op $n2 $n3 orient right
> 
> $ns duplex-link-op $n3 $n4 orient right
> 
> 
> 
> #Monitor the queue for the link between node 3 and node 4
> 
> $ns duplex-link-op $n3 $n4 queuePos 0.5
> 
> 
> 
> #Set  two leaf classes: lowerClass1 and lowerClass2
> 
> set topClass [new CBQClass]
> 
> set lowerClass1 [new CBQClass]
> 
> set lowerClass2 [new CBQClass]
> 
> $topClass setparams none 0 0.80 auto 0 2 0
> 
> $lowerClass1 setparams $topClass true 0.35 auto 1 1 100ms
> 
> $lowerClass2 setparams $topClass true 0.35 auto 2 1 150ms
> 
> 
> 
> set q1 [new Queue/DropTail]
> 
> $q1 set limit_ 20
> 
> set q2 [new Queue/DropTail]
> 
> $q2 set limit_ 30
> 
> 
> 
> $lowerClass1 install-queue $q1
> 
> $lowerClass2 install-queue $q2
> 
> $cbqlink insert $lowerClass1
> 
> $cbqlink insert $lowerClass2
> 
> $cbqlink bind $lowerClass1 1
> 
> $cbqlink bind $lowerClass2 2
> 
> #generate traffic from n1 , n2  to n4 via n3
> 
> set null1 [new Agent/Null]
> 
> $ns attach-agent $n4 $null1
> 
> set s1 [new Agent/UDP]
> 
> $ns attach-agent $n1 $s1
> 
> $ns connect $s1 $null1
> 
> set exp1 [new Application/Traffic/Exponential]
> 
> $exp1 set packet_size_ 210
> 
> $exp1 set burst_time_ 500ms
> 
> $exp1 set idle_time_ 500ms
> 
> $exp1 set rate_ 100k
> 
> $exp1 set fid_ 1
> 
> $exp1 attach-agent $s1
> 
> 
> 
> set s2 [new Agent/UDP]
> 
> $ns attach-agent $n2 $s2
> 
> $ns connect $s2 $null1
> 
> set exp2 [new Application/Traffic/Exponential]
> 
> $exp2 set packet_size_ 210
> 
> $exp2 set burst_time_ 500ms
> 
> $exp2 set idle_time_ 500ms
> 
> $exp2 set rate_ 100k
> 
> $exp2 set fid_ 2
> 
> $exp2 attach-agent $s2
> 
> #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
> 
> }
> 
> 
> 
> $ns at 1.0 "$exp1 start"
> 
> $ns at 1.0 "$exp2 start"
> 
> $ns at 5.0 "$exp1 stop"
> 
> $ns at 5.0 "$exp2 stop"
> 
> #Run the simulation
> 
> $ns run
> 
> The error message is:
> 
> 
> ns: _o59 unknown-flow 256 768 0 0:
>     (_o59 cmd line 1)
>     invoked from within
> "_o59 cmd unknown-flow 256 768 0 0"
>     invoked from within
> "catch "$self cmd $args" ret"
>     (procedure "_o59" line 2)
>     (SplitObject unknown line 2)
>     invoked from within
> "_o59 unknown-flow 256 768 0 0"

-- 
Massimo Pegorer, student
Dipartimento di Elettronica e Informatica
Universita' degli Studi di Padova
Padova - ITALIA