NS2 Tutorial – Part II Internet Computing KUT Youn-Hee Han

Introduction to NS22 A good example set ns [new Simulator] #Open the Trace files set tracefile1 [open out.tr w] $ns trace-all $tracefile1 #Open the NAM trace file set namfile [open out.nam w] $ns namtrace-all $namfile #Define a 'finish' procedure proc finish {} { global ns tracefile1 namfile $ns flush-trace close $tracefile1 close $namfile exec nam out.nam & exit 0 } #Define different colors for data flow (for NAM) $ns color 1 Blue $ns color 2 Red Ns2 for beginner, p15~

Introduction to NS23 A good example #Create six nodex set n0 [$ns node] set n1 [$ns node] set n2 [$ns node] set n3 [$ns node] set n4 [$ns node] set n5 [$ns node] #Create links between the nodes $ns duplex-link $n0 $n2 2Mb 10ms DropTail $ns duplex-link $n1 $n2 2Mb 10ms DropTail $ns simplex-link $n2 $n3 0.1Mb 100ms DropTail $ns simplex-link $n3 $n2 0.1Mb 100ms DropTail $ns duplex-link $n3 $n4 0.5Mb 40ms DropTail $ns duplex-link $n3 $n5 0.5Mb 30ms DropTail #Give node position (for NAM) $ns duplex-link-op $n0 $n2 orient right-down $ns duplex-link-op $n1 $n2 orient right-up $ns simplex-link-op $n2 $n3 orient right $ns simplex-link-op $n3 $n2 orient left $ns duplex-link-op $n3 $n4 orient right-up $ns duplex-link-op $n3 $n5 orient right-down

Introduction to NS24 A good example #Set Queue Size of link (n2-n3) to 20 $ns queue-limit $n2 $n3 5 $ns simplex-link-op $n2 $n3 queuePos 0.5 #Setup a TCP connection set tcp [new Agent/TCP] $ns attach-agent $n0 $tcp set sink [new Agent/TCPSink] $ns attach-agent $n4 $sink $ns connect $tcp $sink $tcp set fid_ 1 $tcp set packetSize_ 552 #Setup a FTP over TCP connection set ftp [new Application/FTP] $ftp attach-agent $tcp

Introduction to NS25 A good example #Setup a UDP connection set udp [new Agent/UDP] $ns attach-agent $n1 $udp set null [new Agent/Null] $ns attach-agent $n5 $null $ns connect $udp $null $udp set fid_ 2 #Setup a CBR over UDP connection set cbr [new Application/Traffic/CBR] $cbr attach-agent $udp $cbr set packetSize_ 1000 $cbr set rate_ 0.01Mb $cbr set random_ false $ns at 0.1 "$ftp start" $ns at 1.0 "$cbr start" $ns at "$ftp stop" $ns at "$cbr stop“ $ns at "finish" $ns run

Introduction to NS26 A Node Architecture Classifier Agent Link Agent Node Addr Port Node entry point Local Link - Agents are either protocol endpoints or related objects that generate/fill-in packet fields. - Classifiers: packet demultiplexers.

Introduction to NS27 A Link Architecture Enq Trace Deq TraceRcv Trace Drp Trace DelayTTLQueue Link entry point Agent/Null Links: keeps track of “from” and “to” node objects.

Introduction to NS28 An Application/Node/Link Architecture Link Application N1 N2 Classifier Agent Node Addr Port Local Classifier Agent Node Addr Port Local Enq TraceDeq TraceRcv Trace Drp Trace DelayTTL Drop head Queue Application

Introduction to NS29 Tracing Trace packets on all links set tracefile1 [open out.tr w] $ns trace-all $tracefile tcp tcp r tcp tcp tcp r tcp tcp tcp r tcp ack ack r ack ack ack r ack ack ack r ack [DIY 1] - grep "+ " out.tr > qqq - grep "+ " out.tr | grep "0 2 tcp" > qqq [DIY 2] - Insert the following into ex1.tcl set linkTraceFile [open out_link.tr w] $ns trace-queue $n0 $n2 $linkTraceFile - grep "+ " out_link.tr > qqq2

Introduction to NS210 “grep” command Some more example of “grep” command grep "+ " out.tr | grep "0 2 tcp" > qqq  To obtain a file containing all lines of out.tr that begin with “+ “ and includes “0 2 tcp” phrase. grep “^r” out.tr > out2.tr  To obtain a file containing all lines of out.tr that begin with the letter ‘r’. grep -r text *  To obtain a lines which has ‘text’.  The lines come from all files of the current directory. grep –r text *.c  To obtain a lines which has ‘text’.  The lines come from all files of the current directory and the extension is ‘*.c’ grep text */*.c  To obtain a lines which has ‘text’.  The lines come from all files of the current directory’s subdirectory and the extension is ‘*.c’

Introduction to NS211 gnuplot Ex1] Make the file, named ‘testplot’ Execute ‘gnuplot’ Type the followings  plot ‘testplot’ w lines 1  plot ‘testplot w points 9  q Ex2] Type the followings  grep "+ " out.tr | grep "0 2 tcp" > qqq Execute ‘gnuplot’  plot ‘qqq’ 2:6 t “size” w lines 1 Ex3] Make the files, ‘fn1’, ‘fn2’, ‘fn3’. Make the file, ‘plotting’, including the codes introduced in Page 37. Execute ‘gnuplot’  Load ‘plotting’