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http://hpds.ee.ncku.edu.tw/~smallko/ns2/
How to measure the throughput, packet drop rate, and end-to-end delay for UDP-based application over wireless networks ?
http://hpds.ee.ncku.edu.tw/~smallko/ns2/
How to measure the throughput, packet drop rate, and end-to-end delay for UDP-based application over wireless networks ?
[scenario]
It consists of 8 mobile nodes: 4 source nodes and 4 destination
node. Each source is a CBR source over UDP. The size of a transmitted packet is
512 bytes. Transmission rate of a node is 600 Kbps. We assumed that the nodes
are in transmission range at a constant distance of 195 m. The simulation time lasted for 80 sec.
[TCL script] source from Joe Naoum-Sawaya
#
====================================================================
# Define Node Configuration paramaters
#====================================================================
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)
8
;# number of mobilenodes
set val(rp)
DSDV
;# routing protocol
set val(x) 500 ;# X dimension of the
topography
set val(y)
500 ;# Y dimension of the topography
Mac/802_11 set RTSThreshold_ 3000
Mac/802_11 set basicRate_ 1Mb
Mac/802_11 set dataRate_ 2Mb
#=====================================================================
# Initialize trace file desctiptors
#=====================================================================
# *** Throughput Trace ***
set f0 [open out02.tr w]
set f1 [open out12.tr w]
set f2 [open out22.tr w]
set f3 [open out32.tr w]
# *** Packet Loss Trace ***
set f4 [open lost02.tr w]
set f5 [open lost12.tr w]
set f6 [open lost22.tr w]
set f7 [open lost32.tr w]
# *** Packet Delay Trace ***
set f8 [open delay02.tr w]
set f9 [open delay12.tr w]
set f10 [open delay22.tr w]
set f11 [open delay32.tr w]
# *** Initialize Simulator ***
set ns_ [new
Simulator]
# *** Initialize Trace file ***
set tracefd [open trace2.tr w]
$ns_ trace-all $tracefd
# *** Initialize Network Animator ***
set namtrace [open sim12.nam w]
$ns_ namtrace-all-wireless $namtrace $val(x) $val(y)
# *** set up topography object ***
set topo [new
Topography]
$topo load_flatgrid
500 500
# Create
General Operations Director (GOD) object. It is used to store
global information about the state of the environment, network, or nodes that
an
# omniscent
observer would have, but that should not be made known to any participant in
the simulation.
create-god $val(nn)
# configure nodes
$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) \
-channelType
$val(chan) \
-topoInstance
$topo \
-agentTrace
ON \
-routerTrace
ON \
-macTrace OFF
\
-movementTrace
OFF
# Create Nodes
for
{set i 0} {$i < $val(nn) } {incr
i} {
set
node_($i) [$ns_ node]
$node_($i) random-motion 0 ;#
disable random motion
}
# Initialize Node Coordinates
$node_(0) set X_ 5.0
$node_(0) set Y_ 5.0
$node_(0) set Z_ 0.0
$node_(1) set X_ 200.0
$node_(1) set Y_ 5.0
$node_(1) set Z_ 0.0
$node_(2) set X_ 5.0
$node_(2) set Y_ 50.0
$node_(2) set Z_ 0.0
$node_(3) set X_ 200.0
$node_(3) set Y_ 50.0
$node_(3) set Z_ 0.0
$node_(4) set X_ 5.0
$node_(4) set Y_ 100.0
$node_(4) set Z_ 0.0
$node_(5) set X_ 200.0
$node_(5) set Y_ 100.0
$node_(5) set Z_ 0.0
$node_(6) set X_ 2.0
$node_(6) set Y_ 150.0
$node_(6) set Z_ 0.0
$node_(7) set X_ 200.0
$node_(7) set Y_ 150.0
$node_(7) set Z_ 0.0
# Setup traffic flow between nodes
# UDP connections between node_(0) and node_(1)
# Create Constant four Bit Rate Traffic sources
set agent1 [new Agent/UDP] ;#
Create UDP Agent
$agent1 set prio_ 0 ;#
Set Its priority to 0
set sink [new Agent/LossMonitor] ;#
Create Loss Monitor Sink in order to be able to trace the number obytes received
$ns_ attach-agent $node_(0) $agent1 ;#
Attach Agent to source node
$ns_ attach-agent $node_(1) $sink ;#
Attach Agent to sink node
$ns_ connect $agent1 $sink
;#
Connect the nodes
set app1 [new Application/Traffic/CBR] ;# Create Constant Bit Rate
application
$app1 set packetSize_ 512 ;#
Set Packet Size to 512 bytes
$app1 set rate_ 600Kb ;#
Set CBR rate to 200 Kbits/sec
$app1 attach-agent $agent1 ;#
Attach Application to agent
set agent2 [new Agent/UDP] ;#
Create UDP Agent
$agent2 set prio_ 1 ;#
Set Its priority to 1
set sink2 [new Agent/LossMonitor] ;#
Create Loss Monitor Sink in order to be able to trace the number obytes received
$ns_ attach-agent $node_(2) $agent2 ;#
Attach Agent to source node
$ns_ attach-agent $node_(3) $sink2 ;# Attach Agent to sink node
$ns_ connect $agent2 $sink2
;#
Connect the nodes
set app2 [new Application/Traffic/CBR] ;# Create Constant Bit Rate
application
$app2 set packetSize_ 512 ;#
Set Packet Size to 512 bytes
$app2 set rate_ 600Kb ;#
Set CBR rate to 200 Kbits/sec
$app2 attach-agent $agent2 ;#
Attach Application to agent
set agent3 [new Agent/UDP] ;#
Create UDP Agent
$agent3 set prio_ 2 ;#
Set Its priority to 2
set sink3 [new Agent/LossMonitor] ;#
Create Loss Monitor Sink in order to be able to trace the number obytes received
$ns_ attach-agent $node_(4) $agent3 ;#
Attach Agent to source node
$ns_ attach-agent $node_(5) $sink3 ;# Attach Agent to sink node
$ns_ connect $agent3 $sink3
;#
Connect the nodes
set app3 [new Application/Traffic/CBR] ;# Create Constant Bit Rate
application
$app3 set packetSize_ 512 ;#
Set Packet Size to 512 bytes
$app3 set rate_ 600Kb ;#
Set CBR rate to 200 Kbits/sec
$app3 attach-agent $agent3 ;#
Attach Application to agent
set agent4 [new Agent/UDP] ;#
Create UDP Agent
$agent4 set prio_ 3 ;#
Set Its priority to 3
set sink4 [new Agent/LossMonitor] ;#
Create Loss Monitor Sink in order to be able to trace the number obytes received
$ns_ attach-agent $node_(6) $agent4 ;#
Attach Agent to source node
$ns_ attach-agent $node_(7) $sink4 ;# Attach Agent to sink node
$ns_ connect $agent4 $sink4
;#
Connect the nodes
set app4 [new Application/Traffic/CBR] ;# Create Constant Bit Rate
application
$app4 set packetSize_ 512 ;#
Set Packet Size to 512 bytes
$app4 set rate_ 600Kb ;#
Set CBR rate to 200 Kbits/sec
$app4 attach-agent $agent4 ;#
Attach Application to agent
# defines the node size in Network Animator
for {set i 0} {$i
< $val(nn)} {incr i} {
$ns_ initial_node_pos $node_($i) 20
}
# Initialize Flags
set holdtime 0
set holdseq 0
set holdtime1 0
set holdseq1 0
set holdtime2 0
set holdseq2 0
set holdtime3 0
set holdseq3 0
set holdrate1 0
set holdrate2 0
set holdrate3 0
set holdrate4 0
# Function To record Statistcis (Bit
Rate, Delay, Drop)
proc record {} {
global sink sink2 sink3 sink4 f0 f1 f2 f3 f4 f5 f6 f7 holdtime holdseq holdtime1 holdseq1 holdtime2 holdseq2 holdtime3
holdseq3 f8 f9 f10 f11
holdrate1 holdrate2 holdrate3 holdrate4
set
ns [Simulator instance]
set time
0.9 ;#Set Sampling Time to 0.9 Sec
set
bw0 [$sink set bytes_]
set
bw1 [$sink2 set bytes_]
set
bw2 [$sink3 set bytes_]
set
bw3 [$sink4 set bytes_]
set
bw4 [$sink set nlost_]
set
bw5 [$sink2 set nlost_]
set
bw6 [$sink3 set nlost_]
set
bw7 [$sink4 set nlost_]
set
bw8 [$sink set lastPktTime_]
set
bw9 [$sink set npkts_]
set
bw10 [$sink2 set lastPktTime_]
set
bw11 [$sink2 set npkts_]
set
bw12 [$sink3 set lastPktTime_]
set
bw13 [$sink3 set npkts_]
set
bw14 [$sink4 set lastPktTime_]
set
bw15 [$sink4 set npkts_]
set now
[$ns now]
#
Record Bit Rate in Trace Files
puts $f0 "$now [expr
(($bw0+$holdrate1)*8)/(2*$time*1000000)]"
puts $f1 "$now [expr
(($bw1+$holdrate2)*8)/(2*$time*1000000)]"
puts $f2 "$now [expr
(($bw2+$holdrate3)*8)/(2*$time*1000000)]"
puts $f3 "$now [expr
(($bw3+$holdrate4)*8)/(2*$time*1000000)]"
#
Record Packet Loss Rate in File
puts $f4 "$now [expr $bw4/$time]"
puts $f5 "$now [expr $bw5/$time]"
puts $f6 "$now [expr $bw6/$time]"
puts $f7 "$now [expr $bw7/$time]"
#
Record Packet Delay in File
if
{ $bw9 > $holdseq } {
puts $f8 "$now [expr ($bw8 - $holdtime)/($bw9 - $holdseq)]"
}
else {
puts $f8 "$now [expr ($bw9 - $holdseq)]"
}
if
{ $bw11 > $holdseq1 } {
puts $f9 "$now [expr ($bw10 -
$holdtime1)/($bw11 - $holdseq1)]"
}
else {
puts $f9 "$now [expr ($bw11 -
$holdseq1)]"
}
if
{ $bw13 > $holdseq2 } {
puts $f10 "$now [expr ($bw12 -
$holdtime2)/($bw13 - $holdseq2)]"
}
else {
puts $f10 "$now [expr ($bw13 -
$holdseq2)]"
}
if
{ $bw15 > $holdseq3 } {
puts $f11 "$now [expr ($bw14 -
$holdtime3)/($bw15 - $holdseq3)]"
}
else {
puts $f11 "$now [expr ($bw15 -
$holdseq3)]"
}
#
Reset Variables
$sink set bytes_ 0
$sink2 set bytes_ 0
$sink3 set bytes_ 0
$sink4 set bytes_ 0
$sink
set nlost_ 0
$sink2
set nlost_ 0
$sink3
set nlost_ 0
$sink4
set nlost_ 0
set
holdtime $bw8
set
holdseq $bw9
set holdrate1 $bw0
set holdrate2 $bw1
set holdrate3 $bw2
set holdrate4 $bw3
$ns at [expr $now+$time]
"record" ;#
Schedule Record after $time interval sec
}
# Start Recording at Time 0
$ns_ at 0.0 "record"
$ns_ at 1.4 "$app1 start" ;#
Start transmission at time t = 1.4 Sec
$ns_ at 10.0 "$app2 start" ;#
Start transmission at time t = 10 Sec
$ns_ at 20.0 "$app3 start" ;#
Start transmission at time t = 20 Sec
$ns_ at 30.0 "$app4 start" ;#
Start transmission at time t = 30 Sec
# Stop Simulation at Time 80 sec
$ns_ at 80.0 "stop"
# Reset Nodes at time 80 sec
for {set i 0} {$i
< $val(nn) } {incr i} {
$ns_ at
80.0 "$node_($i) reset";
}
# Exit Simulatoion at Time 80.01 sec
$ns_ at 80.01 "puts \"NS EXITING...\" ; $ns_
halt"
proc stop {} {
global
ns_ tracefd f0 f1 f2 f3 f4 f5 f6 f7 f8 f9 f10 f11
#
Close Trace Files
close
$f0
close
$f1
close
$f2
close
$f3
close
$f4
close
$f5
close
$f6
close
$f7
close
$f8
close
$f9
close
$f10
close
$f11
#
Plot Recorded Statistics
exec
xgraph out02.tr out12.tr out22.tr out32.tr
-geometry 800x400 &
exec
xgraph lost02.tr lost12.tr lost22.tr lost32.tr
-geometry 800x400 &
exec
xgraph delay02.tr delay12.tr delay22.tr delay32.tr
-geometry 800x400 &
#
Reset Trace File
$ns_
flush-trace
close
$tracefd
exit
0
}
puts
"Starting Simulation..."
$ns_ run
|
[simulation
results]
Throughput:
Analysis: Node 1 starts transmitting at time T =1.4 sec while Node 2
starts transmitting at time T=10 sec. During the period of time [1.4 sec, 10
sec] Node 1 is the only transmitting node using the entire available bandwidth.
This justifies the high performance of Node 1 during the specified interval of
time. At time T=10 sec, Node 2 starts transmission hence sharing channel
resources with Node 1. This explains the heavy reduction of bit rate. In
addition, the bit rate plot experiences heavier oscillations and reduction as
the number of transmitting nodes increases. Oscillations are reflected in heavy
disorders in network performance.
Packet Drop Rate:
Analysis: This figure shows a high packet drop rate whenever the number
of nodes sharing network resources increases. It can be shown that the packet
drop rate in the interval [1.4 sec, 10 sec] is 0. This can be easily justified
since only one node is using the network during this time interval. However
this high-quality performance is deteriorated as more nodes start sharing the
network resources.
Average Packets End to End
Delay:
Analysis: When the number of nodes that are sharing the network
resources, the delay significantly increases and readjusting CW of each node
takes longer time.
[Reference]
J. Naoum-Sawaya, B. Ghaddar,
S. Khawam, H. Safa, H. Artail, and Z. Dawy, "Adaptive
Approach for QoS Support in IEEE 802.11e Wireless LAN," in IEEE
International Conference on Wireless and Mobile Computing , Networking and
Communications (WiMob 2005), Montreal, Canada, August
2005
