text: /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
  /*
   * Copyright (c) 2010 Dean Armstrong
   *
   * 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
   *
   * Author: Dean Armstrong <deanarm@gmail.com>
   */
  
  #include "ns3/string.h"
  #include "ns3/test.h"
  #include "ns3/uinteger.h"
  #include "ns3/boolean.h"
  #include "ns3/double.h"
  #include "ns3/ssid.h"
  #include "ns3/packet-sink.h"
  #include "ns3/yans-wifi-helper.h"
  #include "ns3/mobility-helper.h"
  #include "ns3/internet-stack-helper.h"
  #include "ns3/ipv4-address-helper.h"
  #include "ns3/packet-sink-helper.h"
  #include "ns3/on-off-helper.h"
  
  using namespace ns3;
  
  class WifiMsduAggregatorThroughputTest : public TestCase
  {
  public:
    WifiMsduAggregatorThroughputTest ();
    virtual void DoRun (void);
  
  private:
    bool m_writeResults;
  };
  
  WifiMsduAggregatorThroughputTest::WifiMsduAggregatorThroughputTest ()
    : TestCase ("MsduAggregator throughput test"),
      m_writeResults (false)
  {
  }
  
  void
  WifiMsduAggregatorThroughputTest::DoRun (void)
  {
    WifiHelper wifi;
    WifiMacHelper wifiMac;
    YansWifiPhyHelper wifiPhy = YansWifiPhyHelper::Default ();
    YansWifiChannelHelper wifiChannel = YansWifiChannelHelper::Default ();
    wifiPhy.SetChannel (wifiChannel.Create ());
  
    Ssid ssid = Ssid ("wifi-amsdu-throughput");
    // It may seem a little farcical running an 802.11n aggregation
    // scenario with 802.11b rates (transmit rate fixed to 1 Mbps, no
    // less), but this approach tests the bit we need to without unduly
    // increasing the complexity of the simulation.
    std::string phyMode ("DsssRate1Mbps");
    wifi.SetStandard (WIFI_PHY_STANDARD_80211b);
    wifi.SetRemoteStationManager ("ns3::ConstantRateWifiManager",
                                  "DataMode", StringValue (phyMode),
                                  "ControlMode", StringValue (phyMode));
  
    // Setup the AP, which will be the source of traffic for this test
    // and thus has an aggregator on AC_BE.
    NodeContainer ap;
    ap.Create (1);
    wifiMac.SetType ("ns3::ApWifiMac",
                     "QosSupported", BooleanValue (true),
                     "Ssid", SsidValue (ssid),
                     "BeaconGeneration", BooleanValue (true),
                     "BeaconInterval", TimeValue (MicroSeconds (102400)),
                     "BE_MaxAmsduSize", UintegerValue (4000));
  
    NetDeviceContainer apDev = wifi.Install (wifiPhy, wifiMac, ap);
  
    // Setup one STA, which will be the sink for traffic in this test.
    NodeContainer sta;
    sta.Create (1);
    wifiMac.SetType ("ns3::StaWifiMac",
                     "QosSupported", BooleanValue (true),
                     "Ssid", SsidValue (ssid),
                     "ActiveProbing", BooleanValue (false));
    NetDeviceContainer staDev = wifi.Install (wifiPhy, wifiMac, sta);
  
    // Our devices will have fixed positions
    MobilityHelper mobility;
    mobility.SetMobilityModel ("ns3::ConstantPositionMobilityModel");
    mobility.SetPositionAllocator ("ns3::GridPositionAllocator",
                                   "MinX", DoubleValue (0.0),
                                   "MinY", DoubleValue (0.0),
                                   "DeltaX", DoubleValue (5.0),
                                   "DeltaY", DoubleValue (10.0),
                                   "GridWidth", UintegerValue (2),
                                   "LayoutType", StringValue ("RowFirst"));
    mobility.Install (sta);
    mobility.Install (ap);
  
    // Now we install internet stacks on our devices
    InternetStackHelper stack;
    stack.Install (ap);
    stack.Install (sta);
  
    Ipv4AddressHelper address;
    address.SetBase ("192.168.0.0", "255.255.255.0");
    Ipv4InterfaceContainer staNodeInterface, apNodeInterface;
    staNodeInterface = address.Assign (staDev);
    apNodeInterface = address.Assign (apDev);
  
    // The applications for this test will see a unidirectional UDP
    // stream from the AP to the STA. The following UDP port will be
    // used (arbitrary choice).
    uint16_t udpPort = 50000;
  
    // The packet sink application is on the STA device, and is running
    // right from the start. The traffic source will turn on at 1 second
    // and then off at 9 seconds, so we turn the sink off at 9 seconds
    // too in order to measure throughput in a fixed window.
    PacketSinkHelper packetSink ("ns3::UdpSocketFactory",
                                 InetSocketAddress (Ipv4Address::GetAny (),
                                                    udpPort));
    ApplicationContainer sinkApp = packetSink.Install (sta.Get (0));
    sinkApp.Start (Seconds (0));
    sinkApp.Stop (Seconds (9.0));
  
    // The packet source is an on-off application on the AP
    // device. Given that we have fixed the transmit rate at 1 Mbps
    // above, a 1 Mbps stream at the transport layer should be sufficient
    // to determine whether aggregation is working or not.
    //
    // We configure this traffic stream to operate between 1 and 9 seconds.
    OnOffHelper onoff ("ns3::UdpSocketFactory",
                       InetSocketAddress (staNodeInterface.GetAddress (0),
                                          udpPort));
    onoff.SetAttribute ("PacketSize", UintegerValue (100));
    onoff.SetConstantRate (DataRate ("1Mbps"));
    ApplicationContainer sourceApp = onoff.Install (ap.Get (0));
    sourceApp.Start (Seconds (1.0));
    sourceApp.Stop (Seconds (9.0));
  
    // Enable tracing at the AP
    if (m_writeResults)
      {
        wifiPhy.EnablePcap ("wifi-amsdu-throughput", sta.Get (0)->GetId (), 0);
      }
  
    Simulator::Stop (Seconds (10.0));
    Simulator::Run ();
    Simulator::Destroy ();
  
    // Now the simulation is complete we note the total number of octets
    // receive at the packet sink so that we can shortly test that this
    // is plausible.
    uint32_t totalOctetsThrough =
      DynamicCast<PacketSink>(sinkApp.Get (0))->GetTotalRx ();
  
    // Check that throughput was acceptable. This threshold is set based
    // on inspection of a trace where things are working. Basically, we
    // there get 26 UDP packets (of size 100, as specified above)
    // aggregated per A-MSDU, for which the complete frame exchange
    // (including RTS/CTS and plus medium access) takes around 32
    // ms. Over the eight seconds of the test this means we expect about
    // 650 kilobytes, so a pass threshold of 600000 seems to provide a
    // fair amount of margin to account for reduced utilisation around
    // stream startup, and contention around AP beacon transmission.
    //
    // If aggregation is turned off, then we get about 350 kilobytes in
    // the same test, so we'll definitely catch the major failures.
    NS_TEST_ASSERT_MSG_GT (totalOctetsThrough, 600000,
                           "A-MSDU test fails for low throughput of "
                           << totalOctetsThrough << " octets");
  }
  
  
  // For now the MSDU Aggregator Test Suite contains only the one test
  // that is defined in this file, so it's class definition and
  // instantiation can live here.
  class WifiMsduAggregatorTestSuite : public TestSuite
  {
  public:
    WifiMsduAggregatorTestSuite ();
  };
  
  WifiMsduAggregatorTestSuite::WifiMsduAggregatorTestSuite ()
    : TestSuite ("wifi-msdu-aggregator", SYSTEM)
  {
    AddTestCase (new WifiMsduAggregatorThroughputTest, TestCase::QUICK);
  }
  
  static WifiMsduAggregatorTestSuite wifiMsduAggregatorTestSuite;
  