tcp-linux-reno.cc

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/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2019 NITK Surathkal
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation;
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * Authors: Apoorva Bhargava <apoorvabhargava13@gmail.com>
 */

// Network topology
//
//       n0 ---------- n1 ---------- n2 ---------- n3
//            10 Mbps       1 Mbps        10 Mbps
//             1 ms         10 ms          1 ms
//
// - TCP flow from n0 to n3 using BulkSendApplication.
// - The following simulation output is stored in results/ in ns-3 top-level directory:
//   - cwnd traces are stored in cwndTraces folder
//   - queue length statistics are stored in queue-size.dat file
//   - pcaps are stored in pcap folder
//   - queueTraces folder contain the drop statistics at queue
//   - queueStats.txt file contains the queue stats and config.txt file contains
//     the simulation configuration.
// - The cwnd and queue length traces obtained from this example were tested against
//   the respective traces obtained from Linux Reno by using ns-3 Direct Code Execution.
//   See internet/doc/tcp.rst for more details.

#include <iostream>
#include <string>
#include <fstream>
#include <sys/stat.h>
#include "ns3/core-module.h"
#include "ns3/network-module.h"
#include "ns3/internet-module.h"
#include "ns3/point-to-point-module.h"
#include "ns3/applications-module.h"
#include "ns3/traffic-control-module.h"

using namespace ns3;
std::string dir = "results/";
Time stopTime = Seconds (60);
uint32_t segmentSize = 524;

// Function to check queue length of Router 1
void
CheckQueueSize (Ptr<QueueDisc> queue)
{
  uint32_t qSize = queue->GetCurrentSize ().GetValue ();

  // Check queue size every 1/100 of a second
  Simulator::Schedule (Seconds (0.001), &CheckQueueSize, queue);
  std::ofstream fPlotQueue (std::stringstream (dir + "queue-size.dat").str ().c_str (), std::ios::out | std::ios::app);
  fPlotQueue << Simulator::Now ().GetSeconds () << " " << qSize << std::endl;
  fPlotQueue.close ();
}

// Function to trace change in cwnd at n0
static void
CwndChange (uint32_t oldCwnd, uint32_t newCwnd)
{
  std::ofstream fPlotQueue (dir + "cwndTraces/n0.dat", std::ios::out | std::ios::app);
  fPlotQueue << Simulator::Now ().GetSeconds () << " " << newCwnd / segmentSize << std::endl;
  fPlotQueue.close ();
}

// Function to calculate drops in a particular Queue
static void
DropAtQueue (Ptr<OutputStreamWrapper> stream, Ptr<const QueueDiscItem> item)
{
  *stream->GetStream () << Simulator::Now ().GetSeconds () << " 1" << std::endl;
}

// Trace Function for cwnd
void
TraceCwnd (uint32_t node, uint32_t cwndWindow,
           Callback <void, uint32_t, uint32_t> CwndTrace)
{
  Config::ConnectWithoutContext ("/NodeList/" + std::to_string (node) + "/$ns3::TcpL4Protocol/SocketList/" + std::to_string (cwndWindow) + "/CongestionWindow", CwndTrace);
}

// Function to install BulkSend application
void InstallBulkSend (Ptr<Node> node, Ipv4Address address, uint16_t port, std::string socketFactory,
                      uint32_t nodeId, uint32_t cwndWindow,
                      Callback <void, uint32_t, uint32_t> CwndTrace)
{
  BulkSendHelper source (socketFactory, InetSocketAddress (address, port));
  source.SetAttribute ("MaxBytes", UintegerValue (0));
  ApplicationContainer sourceApps = source.Install (node);
  sourceApps.Start (Seconds (10.0));
  Simulator::Schedule (Seconds (10.0) + Seconds (0.001), &TraceCwnd, nodeId, cwndWindow, CwndTrace);
  sourceApps.Stop (stopTime);
}

// Function to install sink application
void InstallPacketSink (Ptr<Node> node, uint16_t port, std::string socketFactory)
{
  PacketSinkHelper sink (socketFactory, InetSocketAddress (Ipv4Address::GetAny (), port));
  ApplicationContainer sinkApps = sink.Install (node);
  sinkApps.Start (Seconds (10.0));
  sinkApps.Stop (stopTime);
}

int main (int argc, char *argv[])
{
  uint32_t stream = 1;
  std::string socketFactory = "ns3::TcpSocketFactory";
  std::string tcpTypeId = "ns3::TcpLinuxReno";
  std::string qdiscTypeId = "ns3::FifoQueueDisc";
  bool isSack = true;
  uint32_t delAckCount = 1;
  std::string recovery = "ns3::TcpClassicRecovery";

  CommandLine cmd;
  cmd.AddValue ("tcpTypeId", "TCP variant to use (e.g., ns3::TcpNewReno, ns3::TcpLinuxReno, etc.)", tcpTypeId);
  cmd.AddValue ("qdiscTypeId", "Queue disc for gateway (e.g., ns3::CoDelQueueDisc)", qdiscTypeId);
  cmd.AddValue ("segmentSize", "TCP segment size (bytes)", segmentSize);
  cmd.AddValue ("delAckCount", "Delayed ack count", delAckCount);
  cmd.AddValue ("enableSack", "Flag to enable/disable sack in TCP", isSack);
  cmd.AddValue ("stopTime", "Stop time for applications / simulation time will be stopTime", stopTime);
  cmd.AddValue ("recovery", "Recovery algorithm type to use (e.g., ns3::TcpPrrRecovery", recovery);
  cmd.Parse (argc, argv);

  TypeId qdTid;
  NS_ABORT_MSG_UNLESS (TypeId::LookupByNameFailSafe (qdiscTypeId, &qdTid), "TypeId " << qdiscTypeId << " not found");

  // Set recovery algorithm and TCP variant
  Config::SetDefault ("ns3::TcpL4Protocol::RecoveryType", TypeIdValue (TypeId::LookupByName (recovery)));
  if (tcpTypeId.compare ("ns3::TcpWestwoodPlus") == 0)
    {
      // TcpWestwoodPlus is not an actual TypeId name; we need TcpWestwood here
      Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TcpWestwood::GetTypeId ()));
      // the default protocol type in ns3::TcpWestwood is WESTWOOD
      Config::SetDefault ("ns3::TcpWestwood::ProtocolType", EnumValue (TcpWestwood::WESTWOODPLUS));
    }
  else
    {
      TypeId tcpTid;
      NS_ABORT_MSG_UNLESS (TypeId::LookupByNameFailSafe (tcpTypeId, &tcpTid), "TypeId " << tcpTypeId << " not found");
      Config::SetDefault ("ns3::TcpL4Protocol::SocketType", TypeIdValue (TypeId::LookupByName (tcpTypeId)));
    }

  // Create nodes
  NodeContainer leftNodes, rightNodes, routers;
  routers.Create (2);
  leftNodes.Create (1);
  rightNodes.Create (1);

  std::vector <NetDeviceContainer> leftToRouter;
  std::vector <NetDeviceContainer> routerToRight;

  // Create the point-to-point link helpers and connect two router nodes
  PointToPointHelper pointToPointRouter;
  pointToPointRouter.SetDeviceAttribute  ("DataRate", StringValue ("1Mbps"));
  pointToPointRouter.SetChannelAttribute ("Delay", StringValue ("10ms"));
  NetDeviceContainer r1r2ND = pointToPointRouter.Install (routers.Get (0), routers.Get (1));

  // Create the point-to-point link helpers and connect leaf nodes to router
  PointToPointHelper pointToPointLeaf;
  pointToPointLeaf.SetDeviceAttribute    ("DataRate", StringValue ("10Mbps"));
  pointToPointLeaf.SetChannelAttribute   ("Delay", StringValue ("1ms"));
  leftToRouter.push_back (pointToPointLeaf.Install (leftNodes.Get (0), routers.Get (0)));
  routerToRight.push_back (pointToPointLeaf.Install (routers.Get (1), rightNodes.Get (0)));

  InternetStackHelper internetStack;

  internetStack.Install (leftNodes);
  internetStack.Install (rightNodes);
  internetStack.Install (routers);

  // Assign IP addresses to all the network devices
  Ipv4AddressHelper ipAddresses ("10.0.0.0", "255.255.255.0");

  Ipv4InterfaceContainer r1r2IPAddress = ipAddresses.Assign (r1r2ND);
  ipAddresses.NewNetwork ();

  std::vector <Ipv4InterfaceContainer> leftToRouterIPAddress;
  leftToRouterIPAddress.push_back (ipAddresses.Assign (leftToRouter [0]));
  ipAddresses.NewNetwork ();

  std::vector <Ipv4InterfaceContainer> routerToRightIPAddress;
  routerToRightIPAddress.push_back (ipAddresses.Assign (routerToRight [0]));

  Ipv4GlobalRoutingHelper::PopulateRoutingTables ();

  // Set default sender and receiver buffer size as 1MB
  Config::SetDefault ("ns3::TcpSocket::SndBufSize", UintegerValue (1 << 20));
  Config::SetDefault ("ns3::TcpSocket::RcvBufSize", UintegerValue (1 << 20));

  // Set default initial congestion window as 10 segments
  Config::SetDefault ("ns3::TcpSocket::InitialCwnd", UintegerValue (10));

  // Set default delayed ack count to a specified value
  Config::SetDefault ("ns3::TcpSocket::DelAckCount", UintegerValue (delAckCount));

  // Set default segment size of TCP packet to a specified value
  Config::SetDefault ("ns3::TcpSocket::SegmentSize", UintegerValue (segmentSize));

  // Enable/Disable SACK in TCP
  Config::SetDefault ("ns3::TcpSocketBase::Sack", BooleanValue (isSack));

  // Create directories to store dat files
  struct stat buffer;
  int retVal;
  if ((stat (dir.c_str (), &buffer)) == 0)
    {
      std::string dirToRemove = "rm -rf " + dir;
      retVal = system (dirToRemove.c_str ());
      NS_ASSERT_MSG (retVal == 0, "Error in return value");
    }
  std::string dirToSave = "mkdir -p " + dir;
  retVal = system (dirToSave.c_str ());
  NS_ASSERT_MSG (retVal == 0, "Error in return value");
  retVal = system ((dirToSave + "/pcap/").c_str ());
  NS_ASSERT_MSG (retVal == 0, "Error in return value");
  retVal = system ((dirToSave + "/queueTraces/").c_str ());
  NS_ASSERT_MSG (retVal == 0, "Error in return value");
  retVal = system ((dirToSave + "/cwndTraces/").c_str ());
  NS_ASSERT_MSG (retVal == 0, "Error in return value");
  NS_UNUSED (retVal);

  // Set default parameters for queue discipline
  Config::SetDefault (qdiscTypeId + "::MaxSize", QueueSizeValue (QueueSize ("100p")));

  // Install queue discipline on router
  TrafficControlHelper tch;
  tch.SetRootQueueDisc (qdiscTypeId);
  QueueDiscContainer qd;
  tch.Uninstall (routers.Get (0)->GetDevice (0));
  qd.Add (tch.Install (routers.Get (0)->GetDevice (0)).Get (0));

  // Enable BQL
  tch.SetQueueLimits ("ns3::DynamicQueueLimits");

  // Calls function to check queue size
  Simulator::ScheduleNow (&CheckQueueSize, qd.Get (0));

  AsciiTraceHelper asciiTraceHelper;
  Ptr<OutputStreamWrapper> streamWrapper;

  // Create dat to store packets dropped and marked at the router
  streamWrapper = asciiTraceHelper.CreateFileStream (dir + "/queueTraces/drop-0.dat");
  qd.Get (0)->TraceConnectWithoutContext ("Drop", MakeBoundCallback (&DropAtQueue, streamWrapper));

  // Install packet sink at receiver side
  uint16_t port = 50000;
  InstallPacketSink (rightNodes.Get (0), port, "ns3::TcpSocketFactory");

  // Install BulkSend application
  InstallBulkSend (leftNodes.Get (0), routerToRightIPAddress [0].GetAddress (1), port, socketFactory, 2, 0, MakeCallback (&CwndChange));

  // Enable PCAP on all the point to point interfaces
  pointToPointLeaf.EnablePcapAll (dir + "pcap/ns-3", true);

  Simulator::Stop (stopTime);
  Simulator::Run ();

  // Store queue stats in a file
  std::ofstream myfile;
  myfile.open (dir + "queueStats.txt", std::fstream::in | std::fstream::out | std::fstream::app);
  myfile << std::endl;
  myfile << "Stat for Queue 1";
  myfile << qd.Get (0)->GetStats ();
  myfile.close ();

  // Store configuration of the simulation in a file
  myfile.open (dir + "config.txt", std::fstream::in | std::fstream::out | std::fstream::app);
  myfile << "qdiscTypeId " << qdiscTypeId << "\n";
  myfile << "stream  " << stream << "\n";
  myfile << "segmentSize " << segmentSize << "\n";
  myfile << "delAckCount " << delAckCount << "\n";
  myfile << "stopTime " << stopTime.As (Time::S) << "\n";
  myfile.close ();

  Simulator::Destroy ();

  return 0;
}