Appendix III
The following is the PERL script used in for analysis
of the trace file and to
extract the QoS parameters. The script takes the trace file generated by ns-2 after the
simulation is executed.
It calculates throughput, packet loss,
average jitter and average
delay.
#!/usr/bin/perl
#This program is used to calculate the QoS Parameters from
# NS-2 Trace
file as input parameter
#
use List::Util qw[min max];
use strict;
my $infile=$ARGV[0];
my $node=$ARGV[1];
my %packet_info;
my %node_hash ;
if (!open (DATA,"<$infile"))
{
# Print the titles for the columns
print "FileName Throughput PacketLoss MinJitter MaxJitter
AvgJitter MinDelay MaxDelay AvgDelay
Node TypeTraffic NumPackets
\n";
exit;
}
#Start reading the file
while (
)
{
# Filter for packets
if((/MAC.*exp/) || (/MAC.*tcp/) ||(/MAC.*cbr/) ||(/MAC.*udp/))
{
my @x = split(' ');
my
$action=$x[0];
my
$ttime=$x[1];
my $node_id = $x[2];
my $packet_id = $x[5];
my $size = $x[7];
if(/exp/)
{
$packet_info{$packet_id}->{flow} = "exp" ;
}
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elsif (/tcp/)
{
$packet_info{$packet_id}->{flow} = "tcp" ;
}
elsif (/cbr/)
{
$packet_info{$packet_id}->{flow} = "cbr" ;
}
elsif (/udp/)
{
$packet_info{$packet_id}->{flow} = "udp" ;
}
#Read the packet size
$packet_info{$packet_id}->{size} = $size ;
if ($action eq "s")
{
if (!defined $packet_info{$packet_id}->{start})
{
$packet_info{$packet_id}->{start} = $ttime ;
}
$packet_info{$packet_id}->{from_node} = $node_id
;
$node_hash{$node_id} += 1 ;
}
elsif ($action eq "r")
{
#
The packet is received
$packet_info{$packet_id}->{end} = $ttime ;
$packet_info{$packet_id}->{to_node} = $node_id ;
}
elsif ($action eq "D")
{
# The packet is dropped
$packet_info{$packet_id}->{drop} = 1 ;
$packet_info{$packet_id}->{from_node}
=
$node_id
;
}
}
}
print_node_stats ("ALL") ;
print "\n";
foreach (sort keys(%node_hash))
{
print_node_stats ($_);
print "\n";
}
sub print_node_stats ()
{
my $my_node = shift(@_);
my $dropped = 0;
my $transferred = 0;
my
@send_time;
my
@rec_time;
my
@packet_number;
my
@delay;
my
@from_node;
my
@to_node;
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my %flow = 0;
my $count = 0;
my $drop_count = 0;
foreach my $packet (sort {$a <=> $b} keys(%packet_info))
{
if($my_node ne "ALL")
{
if ($packet_info{$packet}->{from_node} ne
$my_node)
{
next;
}
}
{
if ($packet_info{$packet}->{drop} == 1)
{
$dropped += $packet_info{$packet}->{size};
$drop_count++;
}
Else
{
if (defined($packet_info{$packet}->{start})
&& defined($packet_info{$packet}->{end}))
{
$send_time[$count] =
$packet_info{$packet}->{start};
$rec_time[$count] =
$packet_info{$packet}->{end};
$from_node[$count] =
$packet_info{$packet}->{from_node};
$to_node[$count] =
$packet_info{$packet}->{to_node};
$transferred += $packet_info{$packet}-
>{size};
$packet_number[$count] = $packet;
$delay[$count] = $rec_time[$count]-
$send_time[$count] ;
$flow{$from_node[$count]} =
$packet_info{$packet}->{flow};
$count++;
}
else
{
# Some packets are not marked as dropped
but dont have end time so
drop the packet
$dropped += $packet_info{$packet}-
>{size};
$packet_info{$packet}->{drop} = 1;
$drop_count++;
}
}
}
}
my $total_size = @send_time;
my
@jitter;
for my $i (0...$total_size -2)
{
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if ($packet_number[$i+1] == $packet_number[$i])
{
print "$i\n";
}
else
{
# jitter ((recvtime(j)-sendtime(j))-(recvtime(i)-
sendtime(i)))/(j-i), j > i
$jitter[$i] = (($rec_time[$i+1] - $send_time[$i+1])
- ($rec_time[$i] - $send_time[$i]))/($packet_number[$i+1] -
$packet_number[$i]);
}
}
my $sum = 0;
foreach my $jit(@jitter)
{
#Get
absolute value of jitter
$jit = -1*$jit if ($jit < 0);
$sum
+=$jit;
}
my $sum_delay = 0;
foreach
(@delay)
{
#Get absolute value of jitter
$sum_delay
+=$_;
}
my $avg_jitter = $sum/$total_size;
my $avg_delay = $sum_delay/$total_size;
my $per_loss = ($dropped*100)/($dropped + $transferred);
# transferred is in Bytes. To get Kbps we multiply by 8 and
divide by 1000
my $throughput = ($transferred*8)/(($rec_time[$total_size - 1]
-$send_time[0])*1000);
$infile =~ s/\./ /g;
$infile =~ s/tr//g;
print "$infile ";
print " $throughput ";
print "$per_loss ";
print min(@jitter);
print " ";
print max(@jitter);
print " ";
print "$avg_jitter ";
print min(@delay);
print " ";
print max(@delay);
print " ";
print "$avg_delay ";
print "$my_node ";
if($my_node ne "ALL")
{
print "$flow{$my_node} ";
}
print "$total_size ";
}
