COMPUTER NETWORK LABORATORY 18CSL57

PART A-Simulation Exercises

1. Simulate a three nodes point-to-point network with dulpex links between them.Set
the queue size and vary the bandwidth and find the number of packets dropped.

PROCEDURE

 Open the terminal.

 Execute java –jar nsg2.jar.
 In scenario, select new wired scenario.
 Select nodes, create three nodes.
 In links,select duplex-link and connect.
 Apply tcp and tcpsink between two nodes and establish a peer-peer connection
between them.
 Set bandwidth and queue - size
 In application,select ftp for tcp agent.
 In parameters set the simulation time.
 Gototcl and code will be generated.

# This script is created by NSG2 beta1

# <http://wushoupong.googlepages.com/nsg>

#===================================
# Simulation parameters setup
#===================================
set val(stop) 20.0 ;# time of simulation end

#===================================
# Initialization
#===================================
#Create a ns simulator
set ns [new Simulator]

#Open the NS trace file

set tracefile [open p1.tr w]
$ns trace-all $tracefile

#Open the NAM trace file

set namfile [open p1.nam w]
$ns namtrace-all $namfile

#===================================
# Nodes Definition
#===================================
#Create 3 nodes
set n0 [$ns node]
set n1 [$ns node]
set n2 [$ns node]

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#===================================
# Links Definition
#===================================
#Createlinks between nodes
$ns duplex-link $n0 $n1 1.0Mb 10ms DropTail
$ns queue-limit $n0 $n1 5
$ns duplex-link $n0 $n2 1.0Mb 10ms DropTail
$ns queue-limit $n0 $n2 5

#Give node position (for NAM)

$ns duplex-link-op $n0 $n1 orient left-down
$ns duplex-link-op $n0 $n2 orient right-down

#===================================
# Agents Definition
#===================================
#Setup a TCP connection
set tcp0 [new Agent/TCP]
$ns attach-agent $n0 $tcp0
set sink1 [new Agent/TCPSink]
$ns attach-agent $n2 $sink1
$ns connect $tcp0 $sink1
$tcp0 set packetSize_ 1500

#===================================
# Applications Definition
#===================================
#Setup a FTP Application over TCP connection
set ftp0 [new Application/FTP]
$ftp0 attach-agent $tcp0
$ns at 1.0 "$ftp0 start"
$ns at 20.0 "$ftp0 stop"

#===================================
# Termination
#===================================
#Define a 'finish' procedure
proc finish {} {
global ns tracefile namfile
$ns flush-trace
close $tracefile
close $namfile
exec nam p1.nam &
exec echo "number of packets dropped is "&
exec grep -c "^d"pgm1.tr &

exit 0
}

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$ns at $val(stop) "$ns nam-end-wireless $val(stop)"

$ns at $val(stop) "finish"
$ns at $val(stop) "puts \"done\" ; $ns halt"
$ns run

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2. Implement transmission of ping messages/trace route over a network topology

consisting of 6 nodes and find the number of packets dropped due to congestion.

Procedure

 Open the terminal.

 Execute java –jar nsg2.jar.
 In scenario, select new wired scenario.
 Select nodes, create 6 nodes.
 In links,select duplex-link and connect. Set bandwidth to 1MB and queue - size to 2
 Apply tcp and tcpsink between two nodes and establish a peer-peer connection
between them.
 In application ,select ftp for tcp agent.
 In parameters set the simulation time.
 Gototcl and code will be generated.

# Simulation parameters setup

# This script is created by NSG2 beta1

# <http://wushoupong.googlepages.com/nsg>

#===================================
# Simulation parameters setup
#===================================
set val(stop) 20.0 ;# time of simulation end

#===================================
# Initialization
#===================================
#Create a ns simulator
set ns [new Simulator]

#Open the NS trace file

set tracefile [open p2.tr w]
$ns trace-all $tracefile

#Open the NAM trace file

set namfile [open p2.nam w]
$ns namtrace-all $namfile
$ns color 1 red
$ns color 2 blue
$ns color 3 green
$ns color 4 yellow

#===================================
# Nodes Definition
#===================================
#Create 6 nodes
set n0 [$ns node]

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set n1 [$ns node]

set n2 [$ns node]
set n3 [$ns node]
set n4 [$ns node]
set n5 [$ns node]

#===================================
# Links Definition
#===================================
#Createlinks between nodes
$ns duplex-link $n0 $n1 1.0Mb 10ms DropTail
$ns queue-limit $n0 $n1 5
$ns duplex-link $n2 $n1 1.0Mb 10ms DropTail
$ns queue-limit $n2 $n1 5
$ns duplex-link $n2 $n3 1.0Mb 10ms DropTail
$ns queue-limit $n2 $n3 5
$ns duplex-link $n3 $n4 1.0Mb 10ms DropTail
$ns queue-limit $n3 $n4 5
$ns duplex-link $n4 $n5 1.0Mb 10ms DropTail
$ns queue-limit $n4 $n5 5

#Give node position (for NAM)

$ns duplex-link-op $n0 $n1 orient right-down
$ns duplex-link-op $n2 $n1 orient left-down
$ns duplex-link-op $n2 $n3 orient right-down
$ns duplex-link-op $n3 $n4 orient right-up
$ns duplex-link-op $n4 $n5 orient right-down

Agent/Ping instproc recv {from rtt} {

$self instvar node_
puts "node [$node_ id] received a ping answer from $from with with rtt=$rtt ms"
}

#===================================
# Agents Definition
#===================================
#Setup a TCP connection
set tcp0 [new Agent/TCP]
$tcp0 set class_ 1
$ns attach-agent $n1 $tcp0
set sink2 [new Agent/TCPSink]
$ns attach-agent $n3 $sink2
$ns connect $tcp0 $sink2
$tcp0 set packetSize_ 1500

#Setup a UDP connection

set udp1 [new Agent/UDP]
$udp1 set class_ 2
$ns attach-agent $n2 $udp1
set null3 [new Agent/Null]

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$ns attach-agent $n4 $null3

$ns connect $udp1 $null3
$udp1 set packetSize_ 1500

#setup a ping connection

set p0 [new Agent/Ping]

$p0 set class_ 3
$ns attach-agent $n0 $p0

set p1 [new Agent/Ping]

$p1 set class_ 4
$ns attach-agent $n5 $p1
$ns connect $p0 $p1

#===================================
# Applications Definition
#===================================
#Setup a FTP Application over TCP connection
set ftp1 [new Application/FTP]
$ftp1 attach-agent $tcp0
$ns at 1.0 "$ftp1 start"
$ns at 20.0 "$ftp1 stop"

#Setup a CBR Application over UDP connection

set cbr2 [new Application/Traffic/CBR]
$cbr2 attach-agent $udp1
$cbr2 set packetSize_ 1000
$cbr2 set rate_ 1.0Mb
$cbr2 set random_ null
$ns at 1.0 "$cbr2 start"
$ns at 20.0 "$cbr2 stop"

$ns at 1.0 "$p0 send"

$ns at 2.0 "$p1 send"
$ns at 3.0 "$p0 send"
$ns at 3.2 "$p1 send"
$ns at 3.4 "$p0 send"
$ns at 3.6 "$p1 send"
$ns at 4.0 "$p0 send"
$ns at 4.2 "$p1 send"
$ns at 4.4 "$p0 send"
$ns at 4.6 "$p1 send"

#===================================
# Termination
#===================================
#Define a 'finish' procedure

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proc finish {} {
global ns tracefile namfile
$ns flush-trace
close $tracefile
close $namfile
exec nam p2.nam &
puts " no of packets dropped"
exec grep "^d" p2.tr | grep -c "ping" &
exit 0
}
$ns at $val(stop) "$ns nam-end-wireless $val(stop)"
$ns at $val(stop) "finish"
$ns at $val(stop) "puts \"done\" ; $ns halt"
$ns run

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3. Implement an Ethernet LAN using n nodes and set multiple traffic nodes and plot
congestion window for different source / destination.

PROCEDURE

 Open the terminal.

 Execute java –jar nsg2.jar.
 In scenario, select new wired scenario.
 Select nodes, create 6-10 nodes
 In links,select duplex-link and connect.
 Apply tcp and tcpsink between two nodesudp and null agent between two nodes and
establish a peer-peer connection between them.
 In application ,select ftp for tcp agent and cbr for udp agent.
 Set bandwidth and queue - size
 In parameters set the simulation time.
 Gototcl and code will be generated.

# Simulation parameters setup

# This script is created by NSG2 beta1

# <http://wushoupong.googlepages.com/nsg>

#===================================
# Simulation parameters setup
#===================================
set val(stop) 20.0 ;# time of simulation end

#===================================
# Initialization
#===================================
#Create a ns simulator
set ns [new Simulator]

#Open the NS trace file

set tracefile [open p3.tr w]
$ns trace-all $tracefile

#Open the NAM trace file

set namfile [open p3.nam w]
$ns namtrace-all $namfile
set t [open tahoe w]
set r [open reno w]
set v [open vegas w]
#===================================
# Nodes Definition
#===================================
#Create 11 nodes
set n0 [$ns node]

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set n1 [$ns node]

set n2 [$ns node]
set n3 [$ns node]
set n4 [$ns node]
set n5 [$ns node]
set n6 [$ns node]
set n7 [$ns node]
set n8 [$ns node]
set n9 [$ns node]
set n10 [$ns node]

#===================================
# Links Definition
#===================================
#Createlinks between nodes
$ns duplex-link $n0 $n2 1.0Mb 10ms DropTail
$ns queue-limit $n0 $n2 5
$ns duplex-link $n1 $n2 1.0Mb 10ms DropTail
$ns queue-limit $n1 $n2 5
$ns duplex-link $n2 $n3 1.0Mb 10ms DropTail
$ns queue-limit $n2 $n3 5
set lan [$ns newLan "$n3 $n4 $n5 $n6 $n7 $n8 $n9 $n10" 0.5mb 100ms ll
Queue/DropTail MAC/802_3 channel]
#Give node position (for NAM)
$ns duplex-link-op $n0 $n2 orient right-down
$ns duplex-link-op $n1 $n2 orient right-up
$ns duplex-link-op $n2 $n3 orient right-up

#===================================
# Agents Definition
#===================================
#Setup a TCP/Reno connection
set tcp0 [new Agent/TCP/Reno]
$ns attach-agent $n0 $tcp0
set sink1 [new Agent/TCPSink]
$ns attach-agent $n10 $sink1
$ns connect $tcp0 $sink1
$tcp0 set packetSize_ 1500

#Setup a TCP/FullTcp/Tahoe connection

set tcp2 [new Agent/TCP/FullTcp/Tahoe]
$ns attach-agent $n1 $tcp2
set sink3 [new Agent/TCPSink]
$ns attach-agent $n7 $sink3
$ns connect $tcp2 $sink3
$tcp2 set packetSize_ 1500

#Setup a TCP/Vegas connection

set tcp4 [new Agent/TCP/Vegas]
$ns attach-agent $n4 $tcp4

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set sink5 [new Agent/TCPSink]

$ns attach-agent $n9 $sink5
$ns connect $tcp4 $sink5
$tcp4 set packetSize_ 1500

#===================================
# Applications Definition
#===================================
#Setup a FTP Application over TCP/Reno connection
set ftp0 [new Application/FTP]
$ftp0 attach-agent $tcp0
$ns at 1.0 "$ftp0 start"
$ns at 1.0 "plot $tcp0 $r"
$ns at 20.0 "$ftp0 stop"

#Setup a FTP Application over TCP/FullTcp/Tahoe connection

set ftp1 [new Application/FTP]
$ftp1 attach-agent $tcp2
$ns at 1.0 "$ftp1 start"
$ns at 1.0 "plot $tcp2 $t"
$ns at 20.0 "$ftp1 stop"

#Setup a FTP Application over TCP/Vegas connection

set ftp2 [new Application/FTP]
$ftp2 attach-agent $tcp4
$ns at 1.0 "$ftp2 start"
$ns at 1.0 "plot $tcp4 $v"
$ns at 20.0 "$ftp2 stop"

#===================================
# Termination
#===================================
#Define a 'finish' procedure
proc finish {} {
global ns tracefile namfile
$ns flush-trace
close $tracefile
close $namfile
exec nam p3.nam &
exec xgraph reno vegas tahoe &
exit 0
}
proc plot { tcps file} {
global ns
set now [$ns now]
set cwnd [$tcps set cwnd_]
puts $file "$now $cwnd"
$ns at [expr $now+0.1] "plot $tcps $file"

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}
$ns at $val(stop) "$ns nam-end-wireless $val(stop)"
$ns at $val(stop) "finish"
$ns at $val(stop) "puts \"done\" ; $ns halt"
$ns run

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4. Implement simple ESS and with transmitting nodes in wire-less LAN by simulation
and determine the performance with respect to transmission of packets.

PROCEDURE
 Open the terminal.
 Execute java –jar nsg2.jar.
 In scenario, select new wireless scenario.
 Select nodes, create nodes.
 In links,select duplex-link and connect.
 Apply udp and null between two nodes and establish a peer-peer connection between
them.
 In application ,selectcbr for udp agent.
 Set bandwidth and queue - size
 In parameters set the simulation time.
 Gototcl and code will be generated.

# Simulation parameters setup

# This script is created by NSG2 beta1

# <http://wushoupong.googlepages.com/nsg>

#===================================
# Simulation parameters setup
#===================================
set val(chan) Channel/WirelessChannel ;# channel type
set val(prop) Propagation/TwoRayGround ;# radio-propagation model
set val(netif) Phy/WirelessPhy ;# network interface type
set val(mac) Mac/802_11 ;# MAC type
set val(ifq) Queue/DropTail/PriQueue ;# interface queue type
set val(ll) LL ;# link layer type
set val(ant) Antenna/OmniAntenna ;# antenna model
set val(ifqlen) 50 ;# max packet in ifq
set val(nn) 7 ;# number of mobilenodes
set val(rp) DSDV ;# routing protocol
set val(x) 1091 ;# X dimension of topography
set val(y) 781 ;# Y dimension of topography
set val(stop) 200.0 ;# time of simulation end

#===================================
# Initialization
#===================================
#Create a ns simulator
set ns [new Simulator]

#Setup topography object

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set topo [new Topography]

$topo load_flatgrid $val(x) $val(y)
create-god $val(nn)

#Open the NS trace file

set tracefile [open p4.tr w]
$ns trace-all $tracefile

#Open the NAM trace file

set namfile [open p4.nam w]
$ns namtrace-all $namfile
$ns namtrace-all-wireless $namfile $val(x) $val(y)
set chan [new $val(chan)];#Create wireless channel

#===================================
# Mobile node parameter setup
#===================================
$ns node-config -adhocRouting $val(rp) \
-llType $val(ll) \
-macType $val(mac) \
-ifqType $val(ifq) \
-ifqLen $val(ifqlen) \
-antType $val(ant) \
-propType $val(prop) \
-phyType $val(netif) \
-channel $chan \
-topoInstance $topo \
-agentTrace ON \
-routerTrace ON \
-macTrace ON \
-movementTrace ON

#===================================
# Nodes Definition
#===================================
#Create 7 nodes
set n0 [$ns node]
$n0 set X_ 604
$n0 set Y_ 681
$n0 set Z_ 0.0
$ns initial_node_pos $n0 20
set n1 [$ns node]
$n1 set X_ 399
$n1 set Y_ 599
$n1 set Z_ 0.0
$ns initial_node_pos $n1 20
set n2 [$ns node]
$n2 set X_ 798
$n2 set Y_ 602
$n2 set Z_ 0.0

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$ns initial_node_pos $n2 20

set n3 [$ns node]
$n3 set X_ 180
$n3 set Y_ 550
$n3 set Z_ 0.0
$ns initial_node_pos $n3 20
set n4 [$ns node]
$n4 set X_ 465
$n4 set Y_ 419
$n4 set Z_ 0.0
$ns initial_node_pos $n4 20
set n5 [$ns node]
$n5 set X_ 796
$n5 set Y_ 433
$n5 set Z_ 0.0
$ns initial_node_pos $n5 20
set n6 [$ns node]
$n6 set X_ 991
$n6 set Y_ 600
$n6 set Z_ 0.0
$ns initial_node_pos $n6 20

#===================================
# Agents Definition
#===================================
#Setup a UDP connection
set udp0 [new Agent/UDP]
$ns attach-agent $n3 $udp0
set null1 [new Agent/Null]
$ns attach-agent $n6 $null1
$ns connect $udp0 $null1
$udp0 set packetSize_ 1500

#===================================
# Applications Definition
#===================================
#Setup a CBR Application over UDP connection
set cbr0 [new Application/Traffic/CBR]
$cbr0 attach-agent $udp0
$cbr0 set packetSize_ 1000
$cbr0 set rate_ 1.0Mb
$cbr0 set random_ null
$ns at 1.0 "$cbr0 start"
$ns at 200.0 "$cbr0 stop"

#===================================
# Termination
#===================================

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#Define a 'finish' procedure

proc finish {} {
global ns tracefile namfile
$ns flush-trace
close $tracefile
close $namfile
exec nam p4.nam &

set s [exec grep "^s" p4.tr | grep -c "_3_ AGT"]

set r [exec grep "^r" p4.tr | grep -c "_6_ AGT"]

exec echo "number of packets sent= $s" &

exec echo "number of packets received = $r" &
exit 0
}
$ns at 50.0 "$n6 setdest 991 60 20"
$ns at 75.0 "$n6 setdest 399 500 20"

for {set i 0} {$i < $val(nn) } { incr i } {

$ns at $val(stop) "\$n$i reset"
}
$ns at $val(stop) "$ns nam-end-wireless $val(stop)"
$ns at $val(stop) "finish"
$ns at $val(stop) "puts \"done\" ; $ns halt"
$ns run

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5. Implement and study the performance of GSM on NS2/NS3 (Using MAC layer) or
equivalent environment.
PROCEDURE

 Open the terminal.

 Execute java –jar nsg2.jar.
 In scenario, select new wired scenario.
 Select nodes, create 6-10 nodes.
 In links, select duplex-link and connect.
 Apply 2tcp and 2tcpsink between two nodes and establish a peer-peer connection
between them.
 In application,select ftp for tcp agent.
 Set bandwidth and queue - size
 In parameters set the simulation time.
 Go to tcl and code will be generated.

# This script is created by NSG2 beta1

# <http://wushoupong.googlepages.com/nsg>
#===================================
# Simulation parameters setup
#===================================
set val(chan) Channel/WirelessChannel ;# channel type
set val(prop) Propagation/TwoRayGround ;# radio-propagation model
set val(netif) Phy/WirelessPhy ;# network interface type
set val(mac) Mac/802_11 ;# MAC type
set val(ifq) Queue/DropTail/PriQueue ;# interface queue type
set val(ll) LL ;# link layer type
set val(ant) Antenna/OmniAntenna ;# antenna model
set val(ifqlen) 50 ;# max packet in ifq
set val(nn) 10 ;# number of mobilenodes
set val(rp) AODV ;# routing protocol
set val(x) 1035 ;# X dimension of topography
set val(y) 647 ;# Y dimension of topography
set val(stop) 50.0 ;# time of simulation end
set f0 [open throughput.tr w]
set f1 [open lost.tr w]
set f2 [open delay.tr w]
#===================================
# Initialization
#===================================
#Create a ns simulator
set ns [new Simulator]
#Setup topography object
set topo [new Topography]
$topo load_flatgrid $val(x) $val(y)
create-god $val(nn)
#Open the NS trace file
set tracefile [open p5.tr w]
$ns trace-all $tracefile

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#Open the NAM trace file

set namfile [open p5.nam w]
$ns namtrace-all $namfile
$ns namtrace-all-wireless $namfile $val(x) $val(y)
set chan [new $val(chan)];#Create wireless channel
#===================================
# Mobile node parameter setup
#===================================
$ns node-config -adhocRouting $val(rp) \
-llType $val(ll) \
-macType $val(mac) \
-ifqType $val(ifq) \
-ifqLen $val(ifqlen) \
-antType $val(ant) \
-propType $val(prop) \
-phyType $val(netif) \
-channel $chan \
-topoInstance $topo \
-agentTrace ON \
-routerTrace ON \
-macTrace ON \
-movementTrace ON
#===================================
# Nodes Definition
#===================================
#Create 10 nodes
set n0 [$ns node]
$n0 set X_ 135
$n0 set Y_ 547
$n0 set Z_ 0.0
set X1(0) 135
set Y1(0) 547
$ns initial_node_pos $n0 20
set n1 [$ns node]
$n1 set X_ 335
$n1 set Y_ 547
$n1 set Z_ 0.0
set X1(1) 335
set Y1(1) 547
$ns initial_node_pos $n1 20
set n2 [$ns node]
$n2 set X_ 535
$n2 set Y_ 547
$n2 set Z_ 0.0
set X1(2) 535
set Y1(2) 547
$ns initial_node_pos $n2 20
set n3 [$ns node]
$n3 set X_ 735
$n3 set Y_ 547

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$n3 set Z_ 0.0

set X1(3) 735
set Y1(3) 547
$ns initial_node_pos $n3 20
set n4 [$ns node]
$n4 set X_ 935
$n4 set Y_ 547
$n4 set Z_ 0.0
set X1(4) 935
set Y1(4) 547
$ns initial_node_pos $n4 20
set n5 [$ns node]
$n5 set X_ 135
$n5 set Y_ 347
$n5 set Z_ 0.0
set X1(5) 135
set Y1(5) 347
$ns initial_node_pos $n5 20
set n6 [$ns node]
$n6 set X_ 335
$n6 set Y_ 347
$n6 set Z_ 0.0
set X1(6) 335
set Y1(6) 347
$ns initial_node_pos $n6 20
set n7 [$ns node]
$n7 set X_ 535
$n7 set Y_ 347
$n7 set Z_ 0.0
set X1(7) 535
set Y1(7) 347
$ns initial_node_pos $n7 20
set n8 [$ns node]
$n8 set X_ 735
$n8 set Y_ 347
$n8 set Z_ 0.0
set X1(8) 735
set Y1(8) 347
$ns initial_node_pos $n8 20
set n9 [$ns node]
$n9 set X_ 935
$n9 set Y_ 347
$n9 set Z_ 0.0
set X1(9) 935
set Y1(9) 347
$ns initial_node_pos $n9 20
puts "........................................"
set m 0
puts "........................................"
puts "| Node | One hop neighbour |"

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puts "........................................"
for {set i 0} {$i < $val(nn) } {incr i} {
set k 0
for { set j 0} {$j < $val(nn) } {incr j} {
set a [expr $X1($j)-$X1($i)]
set b [expr $a*$a]
set c [expr $Y1($j)-$Y1($i)]
set d [expr $c*$c]
set e [expr $b+$d]
set f 0.5
set g [expr pow($e,$f)]
if {$g <= 200 && $i != $j} {
puts "| node($i) | node($j) |"
set nei($m) $j
set k [expr $k+1]
set m [expr $m+1]
}
}
puts "........................................"
}
puts "Loading connection pattern...."
puts "Loading scenario file...."
#===================================
# Agents Definition
#===================================
#Setup a UDP connection
set udp2 [new Agent/UDP]
$ns attach-agent $n0 $udp2
set sink [new Agent/LossMonitor]
$ns attach-agent $n9 $sink
$ns connect $udp2 $sink
$udp2 set packetSize_ 1500
#===================================
# Applications Definition
#===================================
#Setup a CBR Application over UDP connection
set cbr3 [new Application/Traffic/CBR]
$cbr3 attach-agent $udp2
$cbr3 set packetSize_ 1000
$cbr3 set rate_ 1.0Mb
$cbr3 set random_ null
$ns at 1.0 "$cbr3 start"
$ns at 50.0 "$cbr3 stop"
set holdtime 0
set holdseq 0
set holdrate1 0
proc record {} {
global sink f0 f1 f2 holdtime holdseq holdrate1
set nsi [Simulator instance]
set time 0.9 ;#set sampling time 0.9 sec

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COMPUTER NETWORK LABORATORY 18CSL57

set bw0 [$sink set bytes_]

set bw1 [$sink set nlost_]
set bw2 [$sink set lastPktTime_]
set bw3 [$sink set npkts_]
set now [$nsi now]
# record bit rate in trace files
puts $f0 "$now [expr (($bw0+$holdrate1)*8)/(2*$time*1000000)]"
#record packet loss rate in file
puts $f1 "$now [expr $bw1/$time]"
if { $bw3 > $holdseq } {
puts $f2 "$now [expr ($bw2 - $holdtime)/($bw3 - $holdseq)]"
} else {
puts $f2 "$now [expr ($bw3 - $holdseq)]"
}
$sink set bytes_ 0
$sink set nlost_ 0
set holdtime $bw2
set holdseq $bw3
set holdrate1 $bw0
$nsi at [expr $now+$time] "record" ;#schedule record after $time interval sec
}
#start recording at time 0
$ns at 0.0 "record"
$ns at 10.1 "$n0 setdest 200 560 20"
$ns at 10.1 "$n0 setdest 400 570 20"
$ns at 10.1 "$n0 setdest 600 580 20"
$ns at 10.1 "$n0 setdest 750 590 20"
$ns at 10.1 "$n0 setdest 950 600 20"
$ns at 10.1 "$n0 setdest 300 610 20"
$ns at 10.1 "$n0 setdest 500 620 20"
$ns at 10.1 "$n0 setdest 700 630 20"
$ns at 10.1 "$n0 setdest 800 640 20"
$ns at 10.1 "$n0 setdest 1000 645 20"
$ns at 0.5 "$n0 add-mark m blue square"
$ns at 0.5 "$n9 add-mark m red square"
$ns at 0.5 "$n0 label source"
$ns at 0.5 "$n9 label Destination"
#===================================
# Termination
#===================================
#Define a 'finish' procedure
proc finish {} {
global ns tracefile namfile f0 f1 f2
$ns flush-trace
close $tracefile
close $namfile
close $f0
close $f1
close $f2
exec nam p5.nam &

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COMPUTER NETWORK LABORATORY 18CSL57

exec xgraph throughput.tr &

exec xgraph lost.tr &
exec xgraph delay.tr &
exit 0
}
for {set i 0} {$i < $val(nn) } { incr i } {
$ns at $val(stop) "\$n$i reset"
}
$ns at $val(stop) "$ns nam-end-wireless $val(stop)"
$ns at $val(stop) "finish"
$ns at $val(stop) "puts \"done\" ; $ns halt"
$ns run

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COMPUTER NETWORK LABORATORY 18CSL57

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Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

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Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

6. Implement and study the performance of CDMA on NS2/NS3 (Using stack called
Call net) or equivalent environment.
PROCEDURE

 Open the terminal.

 Execute java –jar nsg2.jar.
 In scenario, select new wireless scenario.
 Select nodes, create nodes.
 In links, select duplex-link and connect.
 Apply udp and null between two nodes and establish a peer-peer connection between
them.
 In application, select cbr for udp agent.
 Set bandwidth and queue - size
 In parameters set the simulation time.
 Go to tcl and code will be generated.

# This script is created by NSG2 beta1

# <http://wushoupong.googlepages.com/nsg>

#===================================
# Simulation parameters setup
#===================================
set val(chan) Channel/WirelessChannel ;# channel type
set val(prop) Propagation/TwoRayGround ;# radio-propagation model
set val(netif) Phy/WirelessPhy ;# network interface type
set val(mac) Mac/802_11 ;# MAC type
set val(ifq) Queue/DropTail/PriQueue ;# interface queue type
set val(ll) LL ;# link layer type
set val(ant) Antenna/OmniAntenna ;# antenna model
set val(ifqlen) 50 ;# max packet in ifq
set val(nn) 20 ;# number of mobilenodes
set val(rp) DSDV ;# routing protocol
set val(x) 1500 ;# X dimension of topography
set val(y) 800 ;# Y dimension of topography
set val(stop) 200.0 ;# time of simulation end

Mac/802_11 set cdma_code_bw_start_ 0

Mac/802_11 set cdma_code_bw_stop_ 63
Mac/802_11 set cdma_code_init_start_ 64
Mac/802_11 set cdma_code_init_stop_ 127
Mac/802_11 set cdma_code_cqich_start_ 128
Mac/802_11 set cdma_code_cqich_stop_ 195
Mac/802_11 set cdma_code_handover_start_ 196
Mac/802_11 set cdma_code_handover_stop_ 255

set f0 [open througput.tr w]

set f1 [open lost.tr w]
set f2 [open delay.tr w]

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COMPUTER NETWORK LABORATORY 18CSL57

#===================================
# Initialization
#===================================
#Create a ns simulator
set ns [new Simulator]

#Setup topography object

set topo [new Topography]
$topo load_flatgrid $val(x) $val(y)
create-god $val(nn)

#Open the NS trace file

set tracefile [open p6.tr w]
$ns trace-all $tracefile

#Open the NAM trace file

set namfile [open p6.nam w]
$ns namtrace-all $namfile
$ns namtrace-all-wireless $namfile $val(x) $val(y)
set chan [new $val(chan)];#Create wireless channel

#===================================
# Mobile node parameter setup
#===================================
$ns node-config -adhocRouting $val(rp) \
-llType $val(ll) \
-macType $val(mac) \
-ifqType $val(ifq) \
-ifqLen $val(ifqlen) \
-antType $val(ant) \
-propType $val(prop) \
-phyType $val(netif) \
-channel $chan \
-topoInstance $topo \
-agentTrace ON \
-routerTrace ON \
-macTrace OFF \
-movementTrace ON

#===================================
# Nodes Definition
#===================================
#Create 20 nodes
set n0 [$ns node]
$n0 set X_ 246
$n0 set Y_ 609
$n0 set Z_ 0.0
$ns initial_node_pos $n0 20
set n1 [$ns node]

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COMPUTER NETWORK LABORATORY 18CSL57

$n1 set X_ 446

$n1 set Y_ 609
$n1 set Z_ 0.0
$ns initial_node_pos $n1 20
set n2 [$ns node]
$n2 set X_ 646
$n2 set Y_ 609
$n2 set Z_ 0.0
$ns initial_node_pos $n2 20
set n3 [$ns node]
$n3 set X_ 846
$n3 set Y_ 609
$n3 set Z_ 0.0
$ns initial_node_pos $n3 20
set n4 [$ns node]
$n4 set X_ 1046
$n4 set Y_ 609
$n4 set Z_ 0.0
$ns initial_node_pos $n4 20
set n5 [$ns node]
$n5 set X_ 246
$n5 set Y_ 409
$n5 set Z_ 0.0
$ns initial_node_pos $n5 20
set n6 [$ns node]
$n6 set X_ 446
$n6 set Y_ 409
$n6 set Z_ 0.0
$ns initial_node_pos $n6 20
set n7 [$ns node]
$n7 set X_ 646
$n7 set Y_ 409
$n7 set Z_ 0.0
$ns initial_node_pos $n7 20
set n8 [$ns node]
$n8 set X_ 846
$n8 set Y_ 409
$n8 set Z_ 0.0
$ns initial_node_pos $n8 20
set n9 [$ns node]
$n9 set X_ 1046
$n9 set Y_ 409
$n9 set Z_ 0.0
$ns initial_node_pos $n9 20
set n10 [$ns node]
$n10 set X_ 246
$n10 set Y_ 209
$n10 set Z_ 0.0
$ns initial_node_pos $n10 20
set n11 [$ns node]

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COMPUTER NETWORK LABORATORY 18CSL57

$n11 set X_ 446

$n11 set Y_ 209
$n11 set Z_ 0.0
$ns initial_node_pos $n11 20
set n12 [$ns node]
$n12 set X_ 646
$n12 set Y_ 209
$n12 set Z_ 0.0
$ns initial_node_pos $n12 20
set n13 [$ns node]
$n13 set X_ 846
$n13 set Y_ 209
$n13 set Z_ 0.0
$ns initial_node_pos $n13 20
set n14 [$ns node]
$n14 set X_ 1046
$n14 set Y_ 209
$n14 set Z_ 0.0
$ns initial_node_pos $n14 20
set n15 [$ns node]
$n15 set X_ 246
$n15 set Y_ 9
$n15 set Z_ 0.0
$ns initial_node_pos $n15 20
set n16 [$ns node]
$n16 set X_ 446
$n16 set Y_ 9
$n16 set Z_ 0.0
$ns initial_node_pos $n16 20
set n17 [$ns node]
$n17 set X_ 646
$n17 set Y_ 9
$n17 set Z_ 0.0
$ns initial_node_pos $n17 20
set n18 [$ns node]
$n18 set X_ 846
$n18 set Y_ 9
$n18 set Z_ 0.0
$ns initial_node_pos $n18 20
set n19 [$ns node]
$n19 set X_ 1046
$n19 set Y_ 9
$n19 set Z_ 0.0
$ns initial_node_pos $n19 20

#===================================
# Agents Definition
#===================================
#Setup a UDP connection
set udp0 [new Agent/UDP]

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COMPUTER NETWORK LABORATORY 18CSL57

$ns attach-agent $n0 $udp0

set sink [new Agent/LossMonitor]
$ns attach-agent $n19 $sink
$ns connect $udp0 $sink
$udp0 set packetSize_ 1500

#===================================
# Applications Definition
#===================================
#Setup a CBR Application over UDP connection
set cbr0 [new Application/Traffic/CBR]
$cbr0 attach-agent $udp0
$cbr0 set packetSize_ 1000
$cbr0 set rate_ 1.0Mb
$cbr0 set random_ null
$ns at 1.0 "$cbr0 start"
$ns at 200.0 "$cbr0 stop"

set holdtime 0
set holdseq 0
set holdrate1 0

proc record {} {
global sink f0 f1 f2 holdtime holdseq holdrate1

set nsi [Simulator instance]

set time 0.9 ;#Set Sampling Time to 0.9 Sec

set bw0 [$sink set bytes_]

set bw1 [$sink set nlost_]
set bw2 [$sink set lastPktTime_]
set bw3 [$sink set npkts_]
set now [$nsi now]

# Record Bit Rate in Trace Files

puts $f0 "$now [expr (($bw0+$holdrate1)*8)/(2*$time*1000000)]"

# Record Packet Loss Rate in File

puts $f1 "$now [expr $bw1/$time]"

if { $bw3 > $holdseq } {

puts $f2 "$now [expr ($bw2 - $holdtime)/($bw3 - $holdseq)]"
} else {
puts $f2 "$now [expr ($bw3 - $holdseq)]"
}

$sink set bytes_ 0

$sink set nlost_ 0

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COMPUTER NETWORK LABORATORY 18CSL57

set holdtime $bw2

set holdseq $bw3
set holdrate1 $bw0
$nsi at [expr $now+$time] "record" ;# Schedule Record after $time interval sec
}

# Start Recording at Time 0

$ns at 0.0 "record"

$ns at 10.1 "$n0 setdest 350 700 20"

$ns at 10.1 "$n1 setdest 550 700 20"
$ns at 10.1 "$n2 setdest 750 700 20"
$ns at 10.1 "$n3 setdest 950 700 20"
$ns at 10.1 "$n4 setdest 1150 700 20"
$ns at 10.1 "$n5 setdest 350 500 20"
$ns at 10.1 "$n6 setdest 550 500 20"
$ns at 10.1 "$n7 setdest 750 500 20"
$ns at 10.1 "$n8 setdest 950 500 20"
$ns at 10.1 "$n9 setdest 1150 500 20"
$ns at 10.1 "$n10 setdest 350 300 20"
$ns at 10.1 "$n11 setdest 550 300 20"
$ns at 10.1 "$n12 setdest 750 300 20"
$ns at 10.1 "$n13 setdest 950 300 20"
$ns at 10.1 "$n14 setdest 1150 300 20"
$ns at 10.1 "$n15 setdest 350 100 20"
$ns at 10.1 "$n16 setdest 550 100 20"
$ns at 10.1 "$n17 setdest 750 100 20"
$ns at 10.1 "$n18 setdest 950 100 20"
$ns at 10.1 "$n19 setdest 1150 100 20"

$ns at 0.5 "$n0 add-mark m blue square"

$ns at 0.5 "$n19 add-mark m red square"

$ns at 0.5 "$n0 label source"

$ns at 0.5 "$n19 label Destination"

#===================================
# Termination
#===================================
#Define a 'finish' procedure
proc finish {} {
global ns tracefile namfile f0 f1 f2
$ns flush-trace
close $tracefile
close $namfile
exec nam p6.nam &
exec xgraph throughput.tr &

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Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

exec xgraph lost.tr &

exec xgraph delay.tr &
exit 0
}
for {set i 0} {$i < $val(nn) } { incr i } {
$ns at $val(stop) "\$n$i reset"
}
$ns at $val(stop) "$ns nam-end-wireless $val(stop)"
$ns at $val(stop) "finish"
$ns at $val(stop) "puts \"done\" ; $ns halt"
$ns run

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COMPUTER NETWORK LABORATORY 18CSL57

PART-B

7. Write a program for error detecting code using CRC-CCITT(16-bits).

package crc;

import java.util.*;

public class Crc {

public static void main(String[] args) {
Scanner scan =new Scanner(System.in);
int n;
System.out.println("enter the size of data:");
n=scan.nextInt();
int data[] = new int[n];
system.out.println("enter the data ,bit by bit");
for(int i=0;i<n;i++)
{
data[i]=scan.nextInt();
}
System.out.println("enter the size of divisor:");
n=scan.nextInt();
int divisor[] = new int[n];
System.out.println("enter the divisor , bit by bit");
for(int i=0;i<n;i++)
{
divisor[i] = scan.nextInt();
}
int remainder[] = divide(data,divisor);
System.out.println("remainder=");
for(int i=0;i<remainder.length-1;i++)
{
System.out.println("remainder[i]");

}
System.out.println("\n the CRC code generated is :");
for(int i=0;i<data.length;i++)
{
System.out.println(data[i]);
}
for(int i=0;i<remainder.length-1;i++)
{
System.out.println(remainder[i]);
}
System.out.println();
int sent_data[]=new int[data.length+remainder.length-1];
System.out.println("enter the DATA recevied at the receiver");
for(int i=0;i<sent_data.length;i++){
sent_data[i]=scan.nextInt();

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COMPUTER NETWORK LABORATORY 18CSL57

}
recieve(sent_data,divisor);
}
static int[] divide(int old_data[],int divisor[]){
int remainder[],i;
int data[]=new int[old_data.length+divisor.length];
System.arraycopy(old_data,0,data,0,old_data.length);
remainder=new int[divisor.length];
System.arraycopy(data,0,remainder,0,divisor.length);
for(i=0;i<old_data.length;i++){
if(remainder[0]==1){
for(int j=1; j<divisor.length;j++)
{
remainder[j-1]=exor(remainder[j],divisor[j]);
}
}
else
{
for(int j=1;j<divisor.length;j++)
{
remainder[j-1]=exor(remainder[j],0);
}
}
remainder [divisor.length-1]= data[i+divisor.length];
}
return remainder;
}
static int exor(int a,int b)
{
if(a==b)
{
return 0;
}
return 1;
}
static void recieve(int data[],int divisor[]){
int remainder[]=divide(data,divisor);
for(int i=0;i<remainder.length;i++)
{
if(remainder[i]!=0)
{
System.out.println("there is an error in recieved data......");
return;
}
}
System.out.println("data recieved without any error");
}
}

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COMPUTER NETWORK LABORATORY 18CSL57

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Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

8.Write a program to find the shortest path between vertices using bellman-ford algorithm.

import java.util.Scanner;
public class BellmanFord
{
private int dist[];
private int n;
public static final int MAX_VALUE=999;
public BellmanFord(int n)
{
this.n=n;
dist=new int[n+1];
}
public void BellmanFordEvaluation(int src, int adj[][])
{
for(int nd=1; nd<=n; nd++)
{
dist[nd]=MAX_VALUE;
}
dist[src]=0;
for(int nd=1; nd<=n-1; nd++)
{
for(int sn=1; sn<=n; sn++)
{
for(int dn=1; dn<=n; dn++)
{
if(adj[sn][dn]!=MAX_VALUE)
{
if(dist[dn]>dist[sn]+adj[sn][dn])
dist[dn]=dist[sn]+adj[sn][dn];
}
}
}
}
for(int sn=1; sn<=n; sn++)
{
for(int dn=1; dn<=n; dn++)
{
if(adj[sn][dn]!=MAX_VALUE)
{
if(dist[dn]>dist[sn]+adj[sn][dn])
System.out.println("The graph contains negative edge cycle.");
}
}
}
for(int vertex=1; vertex<=n; vertex++)
{
System.out.println("Distance of src"+src+"to"+vertex+"is"+dist[vertex]);
}
}

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COMPUTER NETWORK LABORATORY 18CSL57

public static void main(String[] args)

{
int n=0;
int src;
Scanner sc=new Scanner(System.in);
System.out.println("Enter the number of vertices:");
n=sc.nextInt();
int adj[][]=new int[n+1][n+1];
System.out.println("Enter the adjacency matrix:");
for(int sn=1; sn<=n; sn++)
{
for(int dn=1; dn<=n; dn++)
{
adj[sn][dn]=sc.nextInt();
if(sn==dn)
{
adj[sn][dn]=0;
continue;
}
if(adj[sn][dn]==0)
{
adj[sn][dn]=MAX_VALUE;
}}}
System.out.println("Enter the src vertex:");
src=sc.nextInt();
BellmanFord bellmanford=new BellmanFord(n);
bellmanford.BellmanFordEvaluation(src,adj);
}}
OUTPUT

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Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

9.Using TCP/IP sockets, write a client-server program to make the client send the file
name and to make the server send back the contents of the requested file if present.

/*client*/

import java.net.*;
import java.io.*;
import java.util.*;
public class TCPClient
{
public static void main( String args[]) throws Exception
{
Socket sock = new Socket("127.0.0.1",4000);
System.out.println("Enter the filename");
BufferedReader BufRead1 =new BufferedReader(new InputStreamReader(System.in));
String fname =BufRead1.readLine();
OutputStream ostream =sock.getOutputStream();
PrintWriter pw=new PrintWriter(ostream,true);
pw.println(fname);
InputStream istream =sock.getInputStream();
BufferedReader BufRead2 =new BufferedReader(new InputStreamReader(istream));
String str;
while((str=BufRead2.readLine())!=null)
{
System.out.println(str);
}
}
}

/*server*/

import java.net.*;
import java.io.*;
public class TCPServer
{
public static void main(String args []) throws Exception
{
ServerSocket sersock=new ServerSocket(4000);
System.out.println("server ready for transmission");
Socket sock=sersock.accept();
System.out.println("connection is successful and waiting for chatting");
InputStream istream=sock.getInputStream();
BufferedReader bufRead1=new BufferedReader(new InputStreamReader(istream));
String fname=bufRead1.readLine();
System.out.println("the requested file from client is:"+fname);
BufferedReader bufRead2=new BufferedReader(new FileReader(fname));
OutputStream ostream =sock.getOutputStream();

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COMPUTER NETWORK LABORATORY 18CSL57

PrintWriter pw = new PrintWriter(ostream,true);

String str;
while((str=bufRead2.readLine())!=null)
{
pw.println(str);
}
sock.close();
}
}
OUTPUT
Server Side

Client Side

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Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

10. Write a program on datagram socket for client/server to display the messages on
client side, typed at the server side.

/*client side*/

import java.io.*;
import java.net.*;
public class UDPClient{
public static void main(String args[]) throws Exception{
BufferedReader in=new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter the message");
String message=in.readLine();
DatagramSocket clientSocket=new DatagramSocket();
InetAddress IPAddress=InetAddress.getByName("localhost");
byte[] sendData=new byte[1024];
byte[] receiveData=new byte[1024];
sendData=message.getBytes();

DatagramPacket sendPacket=new
DatagramPacket(sendData,sendData.length,IPAddress,9876);
clientSocket.send(sendPacket);
DatagramPacket receivePacket=new DatagramPacket(receiveData,receiveData.length);
clientSocket.receive(receivePacket);
String ServerMessage=new String(receivePacket.getData());
System.out.println("from server:"+ServerMessage);
clientSocket.close();
}
}

/*server side*/
import java.io.*;
import java.util.*;
import java.net.*;
public class UDPServer{
public static void main(String args[]) throws Exception{

BufferedReader in = new BufferedReader(new InputStreamReader(System.in));

DatagramSocket ss = new DatagramSocket(9876);
byte[] sendData=new byte[1024];
byte[] receiveData=new byte[1024];

while(true){
DatagramPacket receivePacket=new DatagramPacket(receiveData,receiveData.length);
ss.receive(receivePacket);
String clientmessage=new String(receivePacket.getData());
System.out.println("from client:"+clientmessage);
InetAddress IPAdd=receivePacket.getAddress();

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COMPUTER NETWORK LABORATORY 18CSL57

int port=receivePacket.getPort();
String message= in.readLine();
sendData=message.getBytes();
DatagramPacket sendPacket=new DatagramPacket(sendData,sendData.length,IPAdd,port);
ss.send(sendPacket);
}
}
}

Client Side

Server Side

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Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

11. Write a program for simple RSA algorithm to encrypt and decrypt the data.

package rsa;
import java.io.*;
import java.math.BigInteger;
import java.util.Random;
public class Rsa {
private BigInteger p,q,n,z,e,d;
private int bitlength=1024;
private Random r;
public Rsa()
{
r=new Random();
p=BigInteger.probablePrime(bitlength, r);
q=BigInteger.probablePrime(bitlength, r);
n=p.multiply(q);
z=p.subtract(BigInteger.ONE).multiply(q.subtract(BigInteger.ONE));
e=BigInteger.probablePrime(bitlength/2, r);
while (z.gcd(e).compareTo(BigInteger.ONE)>1 && e.compareTo(z)>0)
{
e.add(BigInteger.ONE);
}
d=e.modInverse(z);
}

public static void main(String[] args) throws IOException {

Rsa rsa = new Rsa();
DataInputStream in = new DataInputStream(System.in);
String teststring;
System.out.println("enter the plain text:");
teststring = in.readLine();
System.out.println("Encrypting String:" +teststring);
byte[] bytes = teststring.getBytes();

byte[] encrypted = rsa.encrypt(bytes);

System.out.println("String in encrypted: "+encrypted);

byte[] decrypted = rsa.decrypt(encrypted);

System.out.println("Decrypted String: " +new String(decrypted));
}
public byte[] encrypt(byte[] message)
{
return(new BigInteger(message)).modPow(e, n).toByteArray();
}
public byte[] decrypt(byte[] message)
{
return(new BigInteger(message)).modPow(d, n).toByteArray();
}

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Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

}
OUTPUT

42
Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

12. Write a program for congestion control using leaky bucket algorithm.

package leakybucket;
import java.util.Random;
import java.util.Scanner;

public class LeakyBucket {

public static void main(String[] args) throws InterruptedException {

int incoming, outgoing, buck_size, n, store = 0;
Scanner Sc = new Scanner(System.in);

System.out.println("Enter bucket size, outgoing rate,no of inputs and incoming size: ");
buck_size = Sc.nextInt();
outgoing = Sc.nextInt();
n = Sc.nextInt();

while (n != 0) {
System.out.println("Enter the incoming packet size : " );
incoming = Sc.nextInt();
if (incoming <= (buck_size - store)){
store += incoming;
System.out.println("Bucket buffer size is " + store + "out of " + buck_size);
}
else {
System.out.println("Packet Loss " + (incoming - (buck_size - store)));
store = buck_size;
System.out.println("Bucket buffer size is " + store + "out of " + buck_size);

}
store = store - outgoing;
System.out.println("After outgoing : " + store + "packets left out of " + buck_size + "in
buffer");
n--;

Thread.sleep(3000);
}
}
}
OUTPUT

43
Dept.of.CS&E, KVGCE, Sullia
COMPUTER NETWORK LABORATORY 18CSL57

44
Dept.of.CS&E, KVGCE, Sullia