/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

/*

 * 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

 *

 */

#include "ns3/core-module.h"

#include "ns3/simulator-module.h"

#include "ns3/node-module.h"

#include "ns3/helper-module.h"

// Network topology (default)

//

//        n2 n3 n4              .

//         \ | /                .

//          \|/                 .

//     n1--- n0---n5            .

//          /|\                 .

//         / | \                .

//        n8 n7 n6              .

//

using namespace ns3;

NS_LOG_COMPONENT_DEFINE ("Star");

int 

main (int argc, char *argv[])

{

  //

  // Set up some default values for the simulation.

  //

  Config::SetDefault ("ns3::OnOffApplication::PacketSize", UintegerValue (137));

  // ??? try and stick 15kb/s into the data rate

  Config::SetDefault ("ns3::OnOffApplication::DataRate", StringValue ("14kb/s"));

  //

  // Default number of nodes in the star.  Overridable by command line argument.

  //

  uint32_t nSpokes = 8;

  CommandLine cmd;

  cmd.AddValue("nSpokes", "Number of nodes to place in the star", nSpokes);

  cmd.Parse (argc, argv);

  NS_LOG_INFO ("Build star topology.");

  PointToPointHelper pointToPoint;

  pointToPoint.SetDeviceAttribute ("DataRate", StringValue ("5Mbps"));

  pointToPoint.SetChannelAttribute ("Delay", StringValue ("2ms"));

  PointToPointStarHelper star (nSpokes, pointToPoint);

  NS_LOG_INFO ("Install internet stack on all nodes.");

  InternetStackHelper internet;

  star.InstallStack (internet);

  NS_LOG_INFO ("Assign IP Addresses.");

  star.AssignIpv4Addresses (Ipv4AddressHelper ("10.1.1.0", "255.255.255.0"));

  NS_LOG_INFO ("Create applications.");

  //

  // Create a packet sink on the star "hub" to receive packets.  

  // 

  uint16_t port = 50000;

  Address hubLocalAddress (InetSocketAddress (Ipv4Address::GetAny (), port));

  PacketSinkHelper packetSinkHelper ("ns3::TcpSocketFactory", hubLocalAddress);

  ApplicationContainer hubApp = packetSinkHelper.Install (star.GetHub ());

  hubApp.Start (Seconds (1.0));

  hubApp.Stop (Seconds (10.0));

  //

  // Create OnOff applications to send TCP to the hub, one on each spoke node.

  //

  OnOffHelper onOffHelper ("ns3::TcpSocketFactory", Address ());

  onOffHelper.SetAttribute ("OnTime", RandomVariableValue (ConstantVariable (1)));

  onOffHelper.SetAttribute ("OffTime", RandomVariableValue (ConstantVariable (0)));

  ApplicationContainer spokeApps;

  for (uint32_t i = 0; i < star.SpokeCount (); ++i)

    {

      AddressValue remoteAddress (InetSocketAddress (star.GetHubIpv4Address (i), port));

      onOffHelper.SetAttribute ("Remote", remoteAddress);

      spokeApps.Add (onOffHelper.Install (star.GetSpokeNode (i)));

  }

  spokeApps.Start (Seconds (1.0));

  spokeApps.Stop (Seconds (10.0));

  NS_LOG_INFO ("Enable static global routing.");

  //

  // Turn on global static routing so we can actually be routed across the star.

  //

  Ipv4GlobalRoutingHelper::PopulateRoutingTables ();

  NS_LOG_INFO ("Enable pcap tracing.");

  //

  // Do pcap tracing on all point-to-point devices on all nodes.

  //

  pointToPoint.EnablePcapAll ("star");

  NS_LOG_INFO ("Run Simulation.");

  Simulator::Run ();

  Simulator::Destroy ();

  NS_LOG_INFO ("Done.");

  return 0;

}