2

 

set ns [ new Simulator ]

set nf [open lab2.nam w]

$ns namtrace-all $nf

set tf [open lab2.tr w]

$ns trace-all $tf

set n0 [$ns node]

set n1 [$ns node]

set n2 [$ns node]

set n3 [$ns node]

set n4 [$ns node]

set n5 [$ns node]

$n4 shape box

$ns duplex-link $n0 $n4 1005Mb 1ms DropTail

$ns duplex-link $n1 $n4 50Mb 1ms DropTail

$ns duplex-link $n2 $n4 2000Mb 1ms DropTail

$ns duplex-link $n3 $n4 200Mb 1ms DropTail

$ns duplex-link $n4 $n5 1Mb 1ms DropTail

set p1 [new Agent/Ping]

$ns attach-agent $n0 $p1

$p1 set packetSize_ 50000

$p1 set interval_ 0.0001

set p2 [new Agent/Ping]

$ns attach-agent $n1 $p2

set p3 [new Agent/Ping]

$ns attach-agent $n2 $p3

$p3 set packetSize_ 30000

$p3 set interval_ 0.00001

set p4 [new Agent/Ping]

$ns attach-agent $n3 $p4 

set p5 [new Agent/Ping]

$ns attach-agent $n5 $p5

$ns queue-limit $n0 $n4 5

$ns queue-limit $n2 $n4 3

$ns queue-limit $n4 $n5 2

Agent/Ping instproc recv {from rtt} {

$self instvar node_

puts "node [$node_ id]received answer from $from with round trip time $ rtt msec"

}

#please provide space between $node_and id. Nospace between $and from.No

#space between and $ and rtt */

$ns connect $p1 $p5

$ns connect $p3 $p4

proc finish { } {

global ns nf tf

$ns flush-trace

exec nam lab2.nam &

close $nf

close $tf

exit 0

}

$ns at 0.1 "$p1 send"

$ns at 0.2 "$p1 send"

$ns at 0.3 "$p1 send"

$ns at 0.4 "$p1 send"

$ns at 0.5 "$p1 send"

$ns at 0.6 "$p1 send"

$ns at 0.7 "$p1 send"

$ns at 0.8 "$p1 send"

$ns at 0.9 "$p1 send"

$ns at 1.0 "$p1 send"

$ns at 1.1 "$p1 send"

$ns at 1.2 "$p1 send"

$ns at 1.3 "$p1 send"

$ns at 1.4 "$p1 send"

$ns at 1.5 "$p1 send"

$ns at 1.6 "$p1 send"

$ns at 1.7 "$p1 send"

$ns at 1.8 "$p1 send"

$ns at 1.9 "$p1 send"

$ns at 2.0 "$p1 send"

$ns at 2.1 "$p1 send"

$ns at 2.2 "$p1 send"

$ns at 2.3 "$p1 send"

$ns at 2.4 "$p1 send"

$ns at 2.5 "$p1 send"

$ns at 2.6 "$p1 send"

$ns at 2.7 "$p1 send"

$ns at 2.8 "$p1 send"

$ns at 2.9 "$p1 send"

$ns at 0.1 "$p3 send"

$ns at 0.2 "$p3 send"

$ns at 0.3 "$p3 send"

$ns at 0.4 "$p3 send"

$ns at 0.5 "$p3 send"

$ns at 0.6 "$p3 send"

$ns at 0.7 "$p3 send"

$ns at 0.8 "$p3 send"

$ns at 0.9 "$p3 send"

$ns at 1.0 "$p3 send"

$ns at 1.1 "$p3 send"

$ns at 1.2 "$p3 send"

$ns at 1.3 "$p3 send"

$ns at 1.4 "$p3 send"

$ns at 1.5 "$p3 send"

$ns at 1.6 "$p3 send"

$ns at 1.7 "$p3 send"

$ns at 1.8 "$p3 send"

$ns at 1.9 "$p3 send"

$ns at 2.0 "$p3 send"

$ns at 2.1 "$p3 send"

$ns at 2.2 "$p3 send"

$ns at 2.3 "$p3 send"

$ns at 2.4 "$p3 send"

$ns at 2.5 "$p3 send"

$ns at 2.6 "$p3 send"

$ns at 2.7 "$p3 send"

$ns at 2.8 "$p3 send"

$ns at 2.9 "$p3 send"

$ns at 3.0 "finish"

$ns run

AWK File (lab2.awk):

BEGIN{ drop=0; } { if($1=="d") { drop++; } } END{ printf("Total number of %s packets dropped due to congestion =%d\n",$5,drop); }