text: /* -*- 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
   *
   * Authors: Lalith Suresh <suresh.lalith@gmail.com>
   */
  
  // Network topology
  //
  //
  //              172.16.1.0/24
  //        (1.1)  (1.2)  (2.1)  (2.2)
  //
  //         eth0   eth0  eth1    eth0
  //       n0 ========= n1 ========= n2
  //            LAN 1       LAN 2
  //
  // - UDP flows from n0 to n2 via n1.
  // - All nodes are Click based.
  //
  
  #include "ns3/core-module.h"
  #include "ns3/network-module.h"
  #include "ns3/internet-module.h"
  #include "ns3/applications-module.h"
  #include "ns3/csma-module.h"
  #include "ns3/ipv4-click-routing.h"
  #include "ns3/ipv4-l3-click-protocol.h"
  #include "ns3/click-internet-stack-helper.h"
  
  using namespace ns3;
  
  NS_LOG_COMPONENT_DEFINE ("NsclickRouting");
  
  int
  main (int argc, char *argv[])
  {
  #ifdef NS3_CLICK
    std::string clickConfigFolder = "src/click/examples";
  
    CommandLine cmd (__FILE__);
    cmd.AddValue ("clickConfigFolder", "Base folder for click configuration files", clickConfigFolder);
    cmd.Parse (argc, argv);
  
  //
  // Explicitly create the nodes required by the topology (shown above).
  //
    NS_LOG_INFO ("Create nodes.");
    NodeContainer n;
    n.Create (3);
  
  //
  // Install Click on the nodes
  //
    ClickInternetStackHelper clickinternet;
    clickinternet.SetClickFile (n.Get (0), clickConfigFolder + "/nsclick-routing-node0.click");
    clickinternet.SetClickFile (n.Get (1), clickConfigFolder + "/nsclick-ip-router.click");
    clickinternet.SetClickFile (n.Get (2), clickConfigFolder + "/nsclick-routing-node2.click");
    clickinternet.SetRoutingTableElement (n.Get (0), "kernel/rt");
    clickinternet.SetRoutingTableElement (n.Get (1), "u/rt");
    clickinternet.SetRoutingTableElement (n.Get (2), "kernel/rt");
    clickinternet.Install (n);
  
    NS_LOG_INFO ("Create channels.");
  //
  // Explicitly create the channels required by the topology (shown above).
  //
    CsmaHelper csma;
    csma.SetChannelAttribute ("DataRate", DataRateValue (DataRate (5000000)));
    csma.SetChannelAttribute ("Delay", TimeValue (MilliSeconds (2)));
    csma.SetDeviceAttribute ("Mtu", UintegerValue (1400));
    NetDeviceContainer d01 = csma.Install (NodeContainer (n.Get (0), n.Get (1)));
    NetDeviceContainer d12 = csma.Install (NodeContainer (n.Get (1), n.Get (2)));
  
    Ipv4AddressHelper ipv4;
  //
  // We've got the "hardware" in place.  Now we need to add IP addresses.
  //
    NS_LOG_INFO ("Assign IP Addresses.");
    ipv4.SetBase ("172.16.1.0", "255.255.255.0");
    Ipv4InterfaceContainer i01 = ipv4.Assign (d01);
  
    ipv4.SetBase ("172.16.2.0", "255.255.255.0");
    Ipv4InterfaceContainer i12 = ipv4.Assign (d12);
  
    NS_LOG_INFO ("Create Applications.");
  //
  // Create one udpServer applications on node one.
  //
    uint16_t port = 4000;
    UdpServerHelper server (port);
    ApplicationContainer apps = server.Install (n.Get (2));
    apps.Start (Seconds (1.0));
    apps.Stop (Seconds (10.0));
  
  //
  // Create one UdpClient application to send UDP datagrams from node zero to
  // node one.
  //
    uint32_t MaxPacketSize = 1024;
    Time interPacketInterval = Seconds (0.05);
    uint32_t maxPacketCount = 320;
    UdpClientHelper client (i12.GetAddress (1), port);
    client.SetAttribute ("MaxPackets", UintegerValue (maxPacketCount));
    client.SetAttribute ("Interval", TimeValue (interPacketInterval));
    client.SetAttribute ("PacketSize", UintegerValue (MaxPacketSize));
    apps = client.Install (NodeContainer (n.Get (0)));
    apps.Start (Seconds (2.0));
    apps.Stop (Seconds (10.0));
  
    csma.EnablePcap ("nsclick-routing", d01, false);
    csma.EnablePcap ("nsclick-routing", d12, false);
  
  //
  // Now, do the actual simulation.
  //
    NS_LOG_INFO ("Run Simulation.");
    Simulator::Stop (Seconds (20.0));
    Simulator::Run ();
    Simulator::Destroy ();
    NS_LOG_INFO ("Done.");
  #else
    NS_FATAL_ERROR ("Can't use ns-3-click without NSCLICK compiled in");
  #endif
  }
  