CODEWITHSUNDEEP
network-programmingtcpns2ns-3congestion-control
JC1
JC1

Reputation: 686

TCP Congestion window graph (ns-3)

I am trying to plot the graph of the congestion window size of a TCP sender.

I am working with the following example and using ns-3's development branch.

http://intronetworks.cs.luc.edu/current/html/ns3.html

This example implements a simple PointToPoint topology between 2 nodes A and C passing as in the following diagram.

A ----------- B ---------------- C

10Mbps ------- 800Kbps

When I run this example I get the following graph.

enter image description here

I was expecting to see the typical cwnd sawtooth due to dropped packets caused by congestion.

Am I missing something here?

EDIT:

Upon further investigation this might be due to the TrafficControl (see 1.) put in place by the Ipv4AddressHelper. When commenting the following lines of code in src/internet/helper/ipv4-address-helper.cc

  Ptr<TrafficControlLayer> tc = node->GetObject<TrafficControlLayer> ();
  if (tc && DynamicCast<LoopbackNetDevice> (device) == 0 && tc->GetRootQueueDiscOnDevice (device) == 0)
    {
      NS_LOG_LOGIC ("Installing default traffic control configuration");
      TrafficControlHelper tcHelper = TrafficControlHelper::Default ();
      tcHelper.Install (device);
    }

I get this new graph enter image description here

Need to investigate this issue further.

1.Design and Implementation of the Traffic Control Module in ns-3

Upvotes: 1

Views: 1420

Answers (0)

Related Questions