## A test of the emulation facility.  Note that this script# must be run through "nse", the version of the simulator with# the emulation extensions.  It listens on the SAP multicast# address for session announcements, forwards them over a# link with a large (1000ms) delay, while taking a trace.# The effect of the delay should be visible in the trace# file.## If you run this on a non-multicast-capable LAN it will be# highly uninteresting.#set sap_addr 224.2.127.254set sap_port 9875set stoptime 20Class TestEmulTestEmul instproc init {} {	$self instvar ns_	set ns_ [new Simulator]	$ns_ use-scheduler RealTime}TestEmul instproc makenet ntype {	$self instvar net_ ta_	set net_ [new Network/$ntype]	$net_ open readonly	set ta_ [new Agent/Tap]	$ta_ network $net_}TestEmul instproc maketopo { tfname } {	$self instvar ns_ ta_ tfchan_	set n0 [$ns_ node]	set n1 [$ns_ node]	#$ns_ duplex-link $n0 $n1 8Mb 1000ms DropTail	$self dlink $n0 $n1 8Mb 1000ms DropTail	$ns_ attach-agent $n0 $ta_	set na [$ns_ nullagent]	set tfchan_ [open $tfname w]	[$ns_ link $n0 $n1] trace $ns_ $tfchan_	$ns_ attach-agent $n1 $na	$ns_ connect $ta_ $na}TestEmul instproc run {} {	global sap_addr sap_port stoptime	$self instvar net_ ns_	$self makenet IP/UDP	$self maketopo emout.tr	$net_ bind $sap_addr $sap_port	puts "running..."	$ns_ at $stoptime "$self finish"	$ns_ run}TestEmul instproc finish {} {	$self instvar tfchan_ ns_	puts "emulation complete.., writing output file"	$ns_ halt	$ns_ dumpq	close $tfchan_	exit 0}TestEmul instproc dlink { n1 n2 bw delay type } {	$self instvar ns_	$ns_ simplex-link $n1 $n2 $bw $delay $type	$ns_ simplex-link $n2 $n1 $bw $delay $type}TestEmul instanceinstance run