diff --git a/tcp/red-vs-nlred.py b/tcp/red-vs-nlred.py
new file mode 100644
index 0000000..9503d46
--- /dev/null
+++ b/tcp/red-vs-nlred.py
@@ -0,0 +1,156 @@
+#Team Member : Siddhartha Chowdhuri (15CO246), Atul Singh (15CO151), Aswin Manoj (15CO209).
+
+import sys
+import ns.core
+import ns.network
+import ns.internet
+import ns.point_to_point
+import ns.applications
+import ns.point_to_point_layout
+import ns.traffic_control    
+
+def main(argv):
+
+    cmd = ns.core.CommandLine ()
+
+    cmd.nLeaf = 10
+    cmd.maxPackets = 100
+    cmd.modeBytes  = "False"
+    cmd.queueDiscLimitPackets = 1000
+    cmd.minTh = 5
+    cmd.maxTh = 15
+    cmd.pktSize = 512
+    cmd.appDataRate = "10Mbps"
+    cmd.queueDiscType = "RED"
+    cmd.port = 5001
+    cmd.bottleNeckLinkBw = "1Mbps"
+    cmd.bottleNeckLinkDelay = "50ms"
+    cmd.AddValue ("nLeaf","Number of left and right side leaf nodes")
+    cmd.AddValue ("maxPackets","Max Packets allowed in the device queue");
+    cmd.AddValue ("queueDiscLimitPackets","Max Packets allowed in the queue disc")
+    cmd.AddValue ("queueDiscType", "Set Queue disc type to RED or NLRED")
+    cmd.AddValue ("appPktSize", "Set OnOff App Packet Size")
+    cmd.AddValue ("appDataRate", "Set OnOff App DataRate")
+    cmd.AddValue ("modeBytes", "Set Queue disc mode to Packets <false> or bytes <true>")
+    cmd.AddValue ("redMinTh", "RED queue minimum threshold")
+    cmd.AddValue ("redMaxTh", "RED queue maximum threshold")
+    cmd.Parse (sys.argv)
+
+
+    if((cmd.queueDiscType != "RED") and (cmd.queueDiscType != "NLRED")):
+        print ("Invalid queue disc type: Use --queueDiscType=RED or --queueDiscType=NLRED")
+        sys.exit(1)
+
+    ns.core.Config.SetDefault ("ns3::OnOffApplication::PacketSize", ns.core.UintegerValue (cmd.pktSize))
+    ns.core.Config.SetDefault ("ns3::OnOffApplication::DataRate", ns.core.StringValue (cmd.appDataRate))
+    ns.core.Config.SetDefault ("ns3::QueueBase::Mode", ns.core.StringValue ("QUEUE_MODE_PACKETS"))
+    ns.core.Config.SetDefault ("ns3::QueueBase::MaxPackets", ns.core.UintegerValue (cmd.maxPackets))
+
+    if (cmd.modeBytes != 1): #check this once more.
+      ns.core.Config.SetDefault ("ns3::RedQueueDisc::Mode", ns.core.StringValue ("QUEUE_DISC_MODE_PACKETS"))
+      ns.core.Config.SetDefault ("ns3::RedQueueDisc::QueueLimit", ns.core.UintegerValue (cmd.queueDiscLimitPackets))
+
+    else:
+      ns.core.Config.SetDefault ("ns3::RedQueueDisc::Mode", ns.core.StringValue ("QUEUE_DISC_MODE_BYTES"))
+      ns.core.Config.SetDefault ("ns3::RedQueueDisc::QueueLimit", ns.core.UintegerValue (cmd.queueDiscLimitPackets * cmd.pktSize))
+      cmd.minTh *= cmd.pktSize
+      cmd.maxTh *= cmd.pktSize
+
+    ns.core.Config.SetDefault ("ns3::RedQueueDisc::MinTh", ns.core.DoubleValue (cmd.minTh))
+    ns.core.Config.SetDefault ("ns3::RedQueueDisc::MaxTh", ns.core.DoubleValue (cmd.maxTh))
+    ns.core.Config.SetDefault ("ns3::RedQueueDisc::LinkBandwidth", ns.core.StringValue (cmd.bottleNeckLinkBw))
+    ns.core.Config.SetDefault ("ns3::RedQueueDisc::LinkDelay", ns.core.StringValue (cmd.bottleNeckLinkDelay))
+    ns.core.Config.SetDefault ("ns3::RedQueueDisc::MeanPktSize", ns.core.UintegerValue (cmd.pktSize))
+
+    if (cmd.queueDiscType == "NLRED"):
+      # Turn on NLRED
+      ns.core.Config.SetDefault ("ns3::RedQueueDisc::NLRED", BooleanValue (True))
+    
+    bottleNeckLink = ns.point_to_point.PointToPointHelper()
+
+    #Create the point-to-point link helpers
+
+    bottleNeckLink.SetDeviceAttribute  ("DataRate", ns.core.StringValue(cmd.bottleNeckLinkBw))
+    bottleNeckLink.SetChannelAttribute ("Delay", ns.core.StringValue (cmd.bottleNeckLinkDelay))
+
+    pointToPointLeaf = ns.point_to_point.PointToPointHelper()
+
+    pointToPointLeaf.SetDeviceAttribute("DataRate", ns.core.StringValue ("10Mbps"))
+    pointToPointLeaf.SetChannelAttribute("Delay", ns.core.StringValue ("1ms"))
+
+    d = ns.point_to_point_layout.PointToPointDumbbellHelper(cmd.nLeaf, pointToPointLeaf,cmd.nLeaf, pointToPointLeaf,bottleNeckLink)
+
+    # Install Stack.
+    stack = ns.internet.InternetStackHelper()
+
+    for i in xrange(d.LeftCount()):
+      stack.Install (d.GetLeft(i))
+
+    for i in xrange(d.RightCount()):
+        stack.Install (d.GetRight(i))
+
+    stack.Install (d.GetLeft())
+    stack.Install (d.GetRight())
+
+    tchBottleneck = ns.traffic_control.TrafficControlHelper()
+    queueDiscs    = ns.traffic_control.QueueDiscContainer()
+    tchBottleneck.SetRootQueueDisc ("ns3::RedQueueDisc")
+    tchBottleneck.Install(d.GetLeft().GetDevice(0))
+    queueDiscs = tchBottleneck.Install(d.GetRight().GetDevice (0));
+
+    # Assign IP Addresses
+    d.AssignIpv4Addresses (ns.internet.Ipv4AddressHelper (ns.network.Ipv4Address("10.1.1.0"),ns.network.Ipv4Mask("255.255.255.0")), 
+    ns.internet.Ipv4AddressHelper (ns.network.Ipv4Address("10.2.1.0"),ns.network.Ipv4Mask("255.255.255.0")),
+    ns.internet.Ipv4AddressHelper (ns.network.Ipv4Address("10.3.1.0"),ns.network.Ipv4Mask("255.255.255.0")))
+
+    # Install on/off app on all right side nodes
+    clientHelper = ns.applications.OnOffHelper ("ns3::TcpSocketFactory", ns.network.Address ())
+    clientHelper.SetAttribute ("OnTime", ns.core.StringValue ("ns3::UniformRandomVariable[Min=0.|Max=1.]"))
+    clientHelper.SetAttribute ("OffTime", ns.core.StringValue ("ns3::UniformRandomVariable[Min=0.|Max=1.]"))
+
+    sinkLocalAddress = ns.network.Address (ns.network.InetSocketAddress (ns.network.Ipv4Address.GetAny(),cmd.port))
+    packetSinkHelper = ns.applications.PacketSinkHelper ("ns3::TcpSocketFactory", sinkLocalAddress);
+    sinkApps = ns.network.ApplicationContainer ();
+
+    for i in xrange(d.LeftCount()):
+        sinkApps.Add(packetSinkHelper.Install(d.GetLeft(i)))
+
+    sinkApps.Start (ns.core.Seconds(0.0));
+    sinkApps.Stop  (ns.core.Seconds(30.0));
+
+    clientApps = ns.network.ApplicationContainer()
+
+    for i in xrange(d.RightCount()):
+        #Create an on/off app sending packets to the left side
+        remoteAddress = ns.network.AddressValue (ns.network.InetSocketAddress (d.GetLeftIpv4Address(i),cmd.port))
+        clientHelper.SetAttribute ("Remote", remoteAddress)
+        clientApps.Add (clientHelper.Install (d.GetRight(i)))
+
+    clientApps.Start (ns.core.Seconds(1.0));    #Start 1 second after sink
+    clientApps.Stop  (ns.core.Seconds(15.0));   #Stop before the sink
+
+    ns.internet.Ipv4GlobalRoutingHelper.PopulateRoutingTables()
+
+    print("Running the simulation\n")
+
+    ns.core.Simulator.Run()
+
+    st = queueDiscs.Get(0).GetStats()
+
+    if (st.GetNDroppedPackets (ns.traffic_control.RedQueueDisc.UNFORCED_DROP) == 0):
+        print("There should be some unforced drops\n")
+        sys.exit (1);
+
+    if (st.GetNDroppedPackets (ns.traffic_control.QueueDisc.INTERNAL_QUEUE_DROP) != 0):
+        print("There should be zero drops due to queue full\n")
+        sys.exit (1);
+
+    print("*** Stats from the bottleneck queue disc ***\n")
+    print(st)
+    print("\nDestroying the simulation\n")
+
+if __name__ == '__main__':
+    main (sys.argv)
+
+    
+