exemplo1.tcl

set ns [new Simulator]
set nf [open out.nam w]
$ns namtrace-all $nf
proc fim {} {
global ns nf
$ns flush-trace
close $nf
exec nam out.nam
exit 0
}
set n0 [$ns node]
set n1 [$ns node]
$ns duplex-link $n0 $n1 1Mb 10ms DropTail

#Cria um agente UDP e liga-o ao nó n0
set udp0 [new Agent/UDP]
$ns attach-agent $n0 $udp0
#Cria uma fonte de tráfego CBR e liga-a ao udp0
set cbr0 [new Application/Traffic/CBR]
$cbr0 set packetSize_ 500
$cbr0 set interval_ 0.005
$cbr0 attach-agent $udp0

#Cria um agente Null e liga-o ao nó n1
set null0 [new Agent/Null]
$ns attach-agent $n1 $null0

$ns connect $udp0 $null0

$ns at 0.5 "$cbr0 start"
$ns at 4.5 "$cbr0 stop"

$ns at 5.0 fim

$ns run