# a cbr source with an udp agent 
# I estimate flow between 3 and 4 Mb
# My calculation gave me 0.8 or 0.44Mb, wether time to send one packet is included
# or not in cbr interval time between two packets

set ns [new Simulator]

set nam_file [open test.out.nam w]
set trace_file [open test.out.tr w]
$ns namtrace-all $nam_file
$ns trace-all $trace_file

proc finish {} {
    global nam_file trace_file
    close $nam_file
    close $trace_file
    exec nam test.out.nam &
    exit 0
}

#nodes and links
set n0 [$ns node]
set n1 [$ns node]
set n2 [$ns node]
$ns duplex-link $n0 $n1 1Mb 10ms DropTail
# in the next line, a bw of 0.34Mb is ok
# the queue grows with 0.33Mb
$ns duplex-link $n1 $n2 0.34Mb 10ms DropTail
$ns duplex-link-op $n1 $n2 queuePos 0.5

#Sources
set cbr0 [new Application/Traffic/CBR]
$cbr0 set packetSize_ 500
$cbr0 set interval_ 0.005

#Agents
set udp0 [new Agent/UDP]
set null2 [new Agent/Null]
$ns attach-agent $n2 $null2
$ns attach-agent $n0 $udp0
$cbr0 attach-agent $udp0

#Connections
$ns connect $udp0 $null2

$ns at 0.0 "$cbr0 start"
$ns at 5.0 "$cbr0 stop"

$ns at 6 "finish"
$ns run