Nodes creation in NS2

Add the following code to the new file and named it with the extension of tcl. i.e. filename.tcl . To create the file go to the terminal.
Write
gedit filename.tcl

This above command will open a file with the name filename.tcl. Add the following code to the file and save the file.

Now, in order  to run the file go to the Terminal and write the following command.

ns filename.tcl

Code:


#Create a simulator object
set ns [new Simulator]


#Open the NAM trace file

set nf [open o.nam w]
$ns namtrace-all $nf

# create nodes

set n0 [$ns node]
set n1 [$ns node]
set n2 [$ns node]
set n3 [$ns node]
set n4 [$ns node]
set n5 [$ns node]
set n7 [$ns node]
set n8 [$ns node]
set n10 [$ns node]


#Create links between the nodes

$ns duplex-link $n0 $n2 2Mb 10ms DropTail
$ns duplex-link $n1 $n2 2Mb 10ms RED
$ns duplex-link $n2 $n3 1.7Mb 20ms RED
$ns duplex-link $n4 $n5 2Mb 10ms RED
$ns duplex-link $n2 $n8 2Mb 10ms RED
$ns duplex-link $n4 $n10 2Mb 5ms DropTail

#Define a 'finish' procedure

proc finish {} {
        global ns nf
        $ns flush-trace
        #Close the NAM trace file
        close $nf
        #Execute NAM on the trace file
        exec nam o.nam &
        exit 0
}



#Call the finish procedure

$ns at 1.0 "finish"

#Run the simulation

$ns run

The following output will be generated after running the code.
Type the following in terminal.

ns filename.tcl