#Tao mo phong
set ns [new Simulator]

#xuat ra Nam
set nf [open mophong1.nam w]
$ns namtrace-all $nf

#mo file Trace file
set tf [open mophong1.tr w]
$ns trace-all $tf

#Dinh nghia thu tuc "finish"
proc finish {} {
	global ns nf tf
	$ns flush-trace
	close $nf
	close $tf
	exec nam mophong1.nam &
	exit 0
}

#So do ket noi mang
# R1--------R3		     R7
#	     \		    /
#	      \		   /
# 	       R5--------R6
#	       /	   \
#  	      /		    \
#	     /		    R8
# R2--------R4
#
 
#Tao 8 nut mang IP
set R1 [$ns node]
set R2 [$ns node]
set R3 [$ns node]
set R4 [$ns node]
set R5 [$ns node]
set R6 [$ns node]
set R7 [$ns node]
set R8 [$ns node]
 
 
#Khai bao link
$ns duplex-link $R1 $R3 1M 30ms DropTail
$ns duplex-link $R2 $R4 1M 30sm DropTail
$ns duplex-link $R3 $R5 0.3M 20ms DropTail
$ns duplex-link $R4 $R5 0.3M 20ms DropTail
$ns simplex-link $R5 $R6 0.5Mb 70ms DropTail
$ns simplex-link $R6 $R5 0.5Mb 70ms DropTail
$ns duplex-link $R6 $R7 1M 30ms DropTail
$ns duplex-link $R6 $R8 1M 30ms DropTail

#ve so do tren Nam
$ns duplex-link-op $R1 $R3 orient right
$ns duplex-link-op $R2 $R4 orient right
$ns duplex-link-op $R3 $R5 orient right-down

$ns duplex-link-op $R4 $R5 orient right-up

$ns simplex-link-op $R5 $R6 orient right

$ns simplex-link-op $R6 $R5 orient left

$ns duplex-link-op $R6 $R7 orient right-up

$ns duplex-link-op $R6 $R8 orient right-down
 
#Set Queue Size of link (R5-R6) to 10

$ns queue-limit $R5 $R6 10

#Monitor the queue for link (R5-R6). (for NAM)
$ns simplex-link-op $R5 $R6 queuePos 0.5
 

#Setup a TCP connection

set tcp [new Agent/TCP/Newreno]
$ns attach-agent $R1 $tcp

set sink [new Agent/TCPSink/DelAck]
$ns attach-agent $R7 $sink
$ns connect $tcp $sink
$tcp set fid_ 1
$tcp set window_ 8000
$tcp set packetSize_ 552

#Setup a FTP over TCP connection
set ftp [new Application/FTP]
$ftp attach-agent $tcp
$ftp set type_ FTP

#Setup a UDP connection
set udp [new Agent/UDP]
$ns attach-agent $R2 $udp
set null [new Agent/Null]
$ns attach-agent $R8 $null
$ns connect $udp $null
$udp set fid_ 2

$ns color 1 Blue
$ns color 2 Red

#Setup a CBR over UDP connection
set cbr [new Application/Traffic/CBR]
$cbr attach-agent $udp
$cbr set type_ CBR
$cbr set packet_size_ 1000
$cbr set rate_ 0.01mb
$cbr set random_ false

    

$ns at 0.1 "$ftp start"
$ns at 1.0 "$cbr start"
$ns at 5.0 "$cbr stop"
$ns at 5.0 "$ftp stop"
$ns at 5.5 "finish"

$ns run