# Pragmatic General Multicast (PGM), Reliable Multicast## Example script to demonstrate the capabilities of the PGM implementation.## This is a binary tree with one sender and several receivers at the leaf# nodes.## Ryan S. Barnett, 2001# rbarnett@catarina.usc.eduset ns [new Simulator -multicast on]$ns node-config -PGM ON$ns namtrace-all [open out.nam w]$ns color 0 red$ns color 1 black$ns color 2 white$ns color 3 blue$ns color 4 yellow$ns color 5 LightBlue$ns color 6 green$ns color 7 magenta$ns color 8 orangeset height 3set nodeNum [expr 1 << $height]set linkNum [expr $nodeNum - 1]set rcvrNum [expr 1 << [expr $height - 1]]puts "Height $height nodes $nodeNum rcvrs $rcvrNum"set colors { red black white blue yellow LightBlue green magenta orange }## Create multicast group#set group [Node allocaddr]puts "Group addr: $group"# Create source node.set n(0) [$ns node]$n(0) shape "circle"$n(0) color "red"## Create nodes#for {set k 1} {$k < $rcvrNum} {incr k} {        set n($k) [$ns node]        $n($k) shape "circle"}for {set k $rcvrNum} {$k < $nodeNum} {incr k} {        set n($k) [$ns node]        $n($k) shape "circle"        $n($k) color "blue"}#set n(16) [$ns node]#$n(16) shape "circle"#$n(16) color "blue"#set n(17) [$ns node]#$n(17) shape "circle"#$n(17) color "blue"proc makelinks { bw delay pairs } {        global ns n        foreach p $pairs {                set src $n([lindex $p 0])                set dst $n([lindex $p 1])                $ns duplex-link $src $dst $bw $delay DropTail        }}makelinks 1.5Mb 10ms {{ 0 1 }{ 1 2 }{ 1 3 }{ 2 4 }{ 2 5 }{ 3 6 }{ 3 7 }}##Set routing protocol#set mproto DMset mrthandle [$ns mrtproto $mproto {}]## Create loss modules - Cycle is 10,# loss module i drops (i*5)th packet in the cycle#for {set i 0} {$i <= $linkNum} {incr i} {       set loss_module($i) [new PGMErrorModel]       # Drop second ODATA packet every 10 packets.       $loss_module($i) drop-packet ODATA 10 2       $loss_module($i) drop-target [$ns set nullAgent_]}proc insert-loss pairs {        global ns n loss_module        set i 0        foreach p $pairs {                set src $n([lindex $p 0])                set dst $n([lindex $p 1])                $ns lossmodel $loss_module($i) $src $dst                incr i        }}## Insert a loss module#insert-loss {    { 2 4 }    { 2 5 }}## Create Sender#set src [new Agent/PGM/Sender]$ns attach-agent $n(0) $src$src set dst_addr_ $group$src set dst_port_ 0# Attach data source to sender.set cbr [new Application/Traffic/CBR]$cbr attach-agent $src$cbr set rate_ 448Kb$cbr set packetSize_ 210$cbr set random_ 0## Create PGM receivers#set i $rcvrNumfor {set k 0} {$k < $rcvrNum} {incr k} {        set rcv($k) [new Agent/PGM/Receiver]        $ns attach-agent $n($i) $rcv($k)        $ns at 0.01 "$n($i) join-group $rcv($k) $group"        incr i}#set rcv(8) [new Agent/PGM/Receiver]#$ns attach-agent $n(16) $rcv(8)#$ns at 0.01 "$n(16) join-group $rcv(8) $group"#set rcv(9) [new Agent/PGM/Receiver]#$ns attach-agent $n(17) $rcv(9)#$ns at 0.01 "$n(17) join-group $rcv(9) $group"# Set Node-2 PGM Agent to be disabled, only multicast.#set agent2 [$n(2) get-pgm]#$agent2 set pgm_enabled_ 0#set agent4 [$n(4) get-pgm]#$agent4 set pgm_enabled_ 0$ns at 0.3 "$src start-SPM"$ns at 0.5 "$cbr start"$ns at 1.5 "$cbr stop"$ns at 2.0 "$src stop-SPM"$ns at 2.0 "finish"proc finish {} {    global ns src rcv rcvrNum nodeNum n    $src print-stats# Print statistics for each PGM Agent.    for {set k 0} {$k < $nodeNum} {incr k} {	set pgm_agent [$n($k) get-pgm]	$pgm_agent print-stats    }# Print statistics for each receiver.    for {set k 0} {$k < $rcvrNum} {incr k} {	$rcv($k) print-stats    }#$rcv(1) print-all-stats    puts "Simulation Finished"#       puts "Starting Nam.."#       exec nam out.nam &    exit 0}$ns run