ns tcp over ftp

#Create a simulator object

set ns [new Simulator]

#Open the nam trace file

set nf [open out.nam w]

$ns namtrace-all $nf

$ns color 1 Blue

#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

}

#Create two nodes

set n0 [$ns node]

set n1 [$ns node]

#Change the colour of nodes

$n0 color red

$n1 color green

$n0 shape square

$n1 shape square

#Create a duplex link between the nodes

$ns duplex-link $n0 $n1 1Mb 10ms DropTail

# Setup a TCP connection

set tcp [new Agent/TCP]

$tcp set class_ 2

$ns attach-agent $n0 $tcp

set sink [new Agent/TCPSink]

$ns attach-agent $n1 $sink

$ns connect $tcp $sink

$tcp set fid_ 1

# Setup a FTP over TCP connection

set ftp [new Application/FTP]

$ftp attach-agent $tcp

$ftp set type_ FTP

# Schedule events for the CBR and FTP agents

$ns at 1.0 "$ftp start"

$ns at 4.0 "$ftp stop"

$ns at 4.5 "$ns detach-agent $n0 $tcp ; $ns detach-agent $n1 $sink"

#Call the finish procedure after 5 seconds of simulation time

$ns at 5.0 "finish"

#Run the simulation

$ns run