Description:

    This network consists of 4 nodes (Client1, Router1, Client2, Router2 and Endserver1). The duplex link between Client1 and Router1 has 2 Mbps of bandwidth and 50ms of delay. The duplex link between Router1 and Endserver1 has 100Kbps of bandwidth and 100 ms of delay. The duplex link between Client2 and Router2 has 100Kbps bandwidth and 50ms delay. The duplex link between Router2 and Endserver1 has 100Kbps bandwidth and 100ms of delay. Each link between nodes uses a DropTail queue.

File name: “tcp2.tcl”

#-------Event scheduler object creation--------#

set ns [new Simulator]

#-----------creating nam object---------#

set nf [open tcp2.nam w]
$ns namtrace-all $nf
 
set nt [open tcp2.tr w]
$ns trace-all $nt

set proto rlm
 
$ns color 1 red
$ns color 2 blue

#---------- creating client- router- end server node----------------#

set Client1 [$ns node]
set Router1 [$ns node]
set Endserver1 [$ns node]
set Client2 [$ns node]
set Router2 [$ns node]

#---creating duplex link---------#

$ns duplex-link $Client1 $Router1 2Mb 50ms DropTail
$ns duplex-link $Router1 $Endserver1 100Kb 100ms DropTail
$ns duplex-link $Client2 $Router2 100Kb 50ms DropTail
$ns duplex-link $Router2 $Endserver1 100Kb 100ms DropTail

#----------------creating orientation------------------#

$ns duplex-link-op $Client1 $Router1 orient right
$ns duplex-link-op $Router1 $Endserver1 orient right
$ns duplex-link-op $Endserver1 $Router2 orient right
$ns duplex-link-op $Router2 $Client2 orient right

#------------Creating Labeling----------------#

$ns at 0.0 "$Client1 label Client1"
$ns at 0.0 "$Router1 label Router1"
$ns at 0.0 "$Endserver1 label Endserver1"
$ns at 0.0 "$Router2 label Router2"
$ns at 0.0 "$Client2 label Client2"

#-----------Configuring nodes------------#

$Endserver1 shape hexagon
$Router1 shape square
$Router2 shape square
#----------------Establishing queues---------#

$ns duplex-link-op $Client1 $Router1 queuePos 0.5
$ns duplex-link-op $Router1 $Endserver1 queuePos 0.5
$ns duplex-link-op $Client2 $Router2 queuePos 0.5
$ns duplex-link-op $Router2 $Endserver1 queuePos 0.5

#---------finish procedure--------#

proc finish {} {
 
global ns nf nt
$ns flush-trace
close $nf
puts "running nam..."
exec nam tcp2.nam &
exit 0
}

#Calling finish procedure

$ns at 5.0 "finish"
$ns run

#-----How to run-----#

$ns tcp2.tcl

#----------Snapshot-----------#