Lab 4: Co-existing TCP and UDP Traffic

4. Set up a ns-2 simulation with co-existing TCP and UDP Multicast Traffic:

• Setup topology as above
• 1 TCP connection
  source at node 9
  destination at node 1
  1 FTP source attached to node 9's tcp agent
  the FTP source starting at time 0.2 second
• 1 Multicast UDP connection
  use dense mode multicast routing
  sender at node 7
  receivers at node 0 and 2
  1 CBR source attached to node 7's udp agent
  the CBR source starting at time 0.2 second
  the 2 receivers joining the group at time 0.0
• Terminate the simulation at 1.5 second

Creating lab4.tcl

# Creating the core event scheduler
    ...FILL IN...

$ns color 1 red
$ns color 2 blue

# Creating 11 nodes
    ...FILL IN...

# Outputs nam traces
set nf [open out.nam w]
$ns namtrace-all $nf

# Creating 10 links
# All with bandwidth 10Mb, delay 10ms, and DropTail queue
# Except the bottleneck link with bw 1.5Mb, delay 20ms, and RED queue
    ...FILL IN...

# Set queue limit (buffer size) to 5 packets in the bottleneck link
$ns queue-limit $n(3) $n(4) ...FILL IN...
$ns queue-limit $n(4) $n(3) ...FILL IN...

# Set link orientation for nam 
$ns duplex-link-op $n(0) $n(3) orient right-down
$ns duplex-link-op $n(1) $n(3) orient right
$ns duplex-link-op $n(2) $n(3) orient right-up
$ns duplex-link-op $n(3) $n(4) orient right
$ns duplex-link-op $n(4) $n(5) orient right-up
$ns duplex-link-op $n(4) $n(6) orient right-down
$ns duplex-link-op $n(5) $n(7) orient right-up
$ns duplex-link-op $n(5) $n(8) orient right
$ns duplex-link-op $n(6) $n(9) orient right
$ns duplex-link-op $n(6) $n(10) orient right-down

# Set queue position for nam 
$ns duplex-link-op $n(3) $n(4) queuePos -0.5
$ns duplex-link-op $n(4) $n(3) queuePos -0.5

# Set multicast routing to dense mode
    ...FILL IN...


# Create a TCP connection from node 9 to node 1
    ...FILL IN...
$tcp set class_ 1
$tcp set window_ 20

# Create an FTP source and attach it to the TCP connection
    ...FILL IN...

# Create a UDP connection from node 7 to a multicast group
    ...FILL IN...
$udp set class_ 2

# Create a CBR source and attach it to the UDP connection
    ...FILL IN...

# Create dummy receivers and attach them to the receiving nodes
set rcvr0 [new Agent/Null]
$ns attach-agent $n(0) $rcvr0
set rcvr1 [new Agent/Null]
$ns attach-agent $n(2) $rcvr1

# Schedule events to happen
    ...FILL IN...


# A finish proc to flush traces and out call nam
proc finish {} {
        global ns nf
        $ns flush-trace
        close $nf

        puts "running nam..."
        exec nam out.nam &
        exit 0
}

# Start the event scheduler
$ns run
    

prompt> ns lab4.tcl

References:

• The main VINT/ns page
• The ns Manual page