#simulator instance
set ns [new Simulator]

$ns color 1 blue 
$ns color 2 red

#Open file for nam trace file
set nf [open out1.nam w]
$ns namtrace-all $nf 

#Finish procedure
proc finish {} {
	global ns nf 
	$ns flush-trace 
	#close trace file
	close $nf
	#execute nam 
	exec nam out1.nam &
	exit 0
}

#define topology
#
#	   r2--r5
# 	  /      \ 
# n1---r1         r4---n2
#         \      /
#	   \_r3_/
#	
# packet to be routed from: n1-r1-r2-r5-r4-n2
##########################
#Define nodes
set n1 [new ManualRtNode]
set n2 [new ManualRtNode]
set r1 [new ManualRtNode]
set r2 [new ManualRtNode]
set r3 [new ManualRtNode]
set r4 [new ManualRtNode]
set r5 [new ManualRtNode]

#Define links
$ns duplex-link $n1 $r1 1Mb 10ms DropTail
$ns duplex-link $r1 $r2 1Mb 10ms DropTail
$ns duplex-link $r2 $r5 1Mb 10ms DropTail
$ns duplex-link $r1 $r3 1Mb 10ms DropTail
$ns duplex-link $r5 $r4 1Mb 10ms DropTail
$ns duplex-link $r3 $r4 1Mb 10ms DropTail
$ns duplex-link $r4 $n2 1Mb 10ms DropTail

# manual set route
$n1 add-route-to-adj-node $r1
$r1 add-route-to-adj-node $r2
$r2 add-route-to-adj-node $r5
$r5 add-route-to-adj-node $r4 
$r4 add-route-to-adj-node $n2

#Define agent
set udp1 [new Agent/UDP]
$ns attach-agent $n1 $udp1
set cbr1 [new Application/Traffic/CBR]
$cbr1 set packetSize_ 100
$cbr1 set rate_ 1Mb
$cbr1 set fid_ 1
$cbr1 attach-agent $udp1

set udp2 [new Agent/UDP]
$ns attach-agent $n1 $udp2
set cbr2 [new Application/Traffic/CBR]
$cbr2 set packetSize_ 100
$cbr2 set rate_ 1Mb
$cbr2 set fid_ 2
$cbr2 attach-agent $udp2

set sink1 [new Agent/LossMonitor]
$ns attach-agent $n2 $sink1
$ns connect $udp1 $sink1

set sink2 [new Agent/LossMonitor]
$ns attach-agent $n2 $sink2
$ns connect $udp2 $sink2

# event
$ns at 0.05 "$cbr1 start"
$ns at 0.10 "$cbr2 start"
$ns at 5.0 "$cbr1 stop"
$ns at 4.0 "$cbr2 stop"

$ns at 5.05 "finish"

$ns run