Hi would anyone be able to help me, i think i have created a Sink
Agent/LossMonitor monitor the nodes however the results come back as always
0.
If anyone can see where i have gone wrong I would be extremely grateful if
you could show me how/where I went wrong.
Thanking you,
Mark
#Create a simulator object
set ns [new Simulator]
#Open a trace file
set f0 [open out0.tr w]
set f1 [open out1.tr w]
set f2 [open out2.tr w]
set nf [open out.nam w]
$ns namtrace-all $nf
#Define a 'finish' procedure
proc finish {} {
global ns nf f0 f1 f2
$ns flush-trace
close $nf
close $f0
close $f1
close $f2
#Call nam to display the results
puts "running nam..."
exec nam -f dynamic-nam.conf out.nam &
#Call xgraph to display the results
puts "running xgraph..."
exec xgraph out0.tr out1.tr out2.tr -geometry 800x400 &
exit 0
}
#Define a procedure which periodically records the bandwidth received by the
#three traffic sinks sink0/1/2 and writes it to the three files f0/1/2.
proc record {} {
global sink0 sink1 sink2 f0 f1 f2
#Get an instance of the simulator
set ns [Simulator instance]
#Set the time after which the procedure should be called again
set time 0.1
#How many bytes have been received by the traffic sinks?
set bw0 [$sink0 set bytes_]
set bw1 [$sink1 set bytes_]
set bw2 [$sink2 set bytes_]
#Get the current time
set now [$ns now]
#Calculate the bandwidth (in MBit/s) and write it to the files
puts $f0 "$now [expr $bw0/$time*8/1000000]"
puts $f1 "$now [expr $bw1/$time*8/1000000]"
puts $f2 "$now [expr $bw2/$time*8/1000000]"
puts "$now $bw0"
#Reset the bytes_ values on the traffic sinks
$sink0 set bytes_ 0
$sink1 set bytes_ 0
$sink2 set bytes_ 0
#Re-schedule the procedure
$ns at [expr $now+$time] "record"
}
#Create three nodes
set n0 [$ns node]
set n1 [$ns node]
set n2 [$ns node]
#Connect the nodes with two links
$ns duplex-link $n0 $n1 1Mb 10ms DropTail
$ns duplex-link $n1 $n2 1Mb 10ms DropTail
#Define a 'recv' function for the class 'Agent/Ping'
Agent/Ping instproc recv {from rtt} {
$self instvar node_
#puts "node [$node_ id] received ping answer from \
# $from with round-trip-time $rtt ms."
}
#Create three traffic sinks and attach them to the node n4
set sink0 [new Agent/LossMonitor]
set sink1 [new Agent/LossMonitor]
set sink2 [new Agent/LossMonitor]
$ns attach-agent $n0 $sink0
$ns attach-agent $n1 $sink1
$ns attach-agent $n2 $sink2
#Create two ping agents and attach them to the nodes n0 and n2
Agent/Ping set packetSize_ 400
set p0 [new Agent/Ping]
$ns attach-agent $n0 $p0
set p1 [new Agent/Ping]
$ns attach-agent $n2 $p1
#Connect the two agents
$ns connect $p0 $p1
#Schedule events
$ns at 0.0 "record"
$ns at 0.2 "$p0 send"
$ns at 0.4 "$p1 send"
$ns at 0.6 "$p0 send"
$ns at 0.6 "$p1 send"
$ns at 1.0 "finish"
#Run the simulation
$ns run
