wifi-aggregation-test.cc

Go to the documentation of this file.

/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2015
 *
 * 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: Sébastien Deronne <sebastien.deronne@gmail.com>
 */
 
#include "ns3/string.h"
#include "ns3/test.h"
#include "ns3/simulator.h"
#include "ns3/wifi-mac-queue.h"
#include "ns3/wifi-psdu.h"
#include "ns3/sta-wifi-mac.h"
#include "ns3/yans-wifi-phy.h"
#include "ns3/interference-helper.h"
#include "ns3/mac-tx-middle.h"
#include "ns3/ht-frame-exchange-manager.h"
#include "ns3/msdu-aggregator.h"
#include "ns3/mpdu-aggregator.h"
#include "ns3/wifi-net-device.h"
#include "ns3/ht-configuration.h"
#include "ns3/vht-configuration.h"
#include "ns3/he-configuration.h"
#include "ns3/node-container.h"
#include "ns3/yans-wifi-helper.h"
#include "ns3/mobility-helper.h"
#include "ns3/pointer.h"
#include "ns3/packet-socket-server.h"
#include "ns3/packet-socket-client.h"
#include "ns3/packet-socket-helper.h"
#include "ns3/wifi-default-protection-manager.h"
#include "ns3/wifi-default-ack-manager.h"
#include <iterator>
#include <algorithm>
 
using namespace ns3;
 
class AmpduAggregationTest : public TestCase
{
public:
  AmpduAggregationTest ();
 
private:
  void MpduDiscarded (WifiMacDropReason reason, Ptr<const WifiMacQueueItem> mpdu);
 
  void DoRun (void) override;
  Ptr<WifiNetDevice> m_device; 
  Ptr<StaWifiMac> m_mac; 
  Ptr<YansWifiPhy> m_phy; 
  Ptr<WifiRemoteStationManager> m_manager; 
  ObjectFactory m_factory; 
  bool m_discarded; 
};
 
AmpduAggregationTest::AmpduAggregationTest ()
  : TestCase ("Check the correctness of MPDU aggregation operations"),
    m_discarded (false)
{
}
 
void
AmpduAggregationTest::MpduDiscarded (WifiMacDropReason, Ptr<const WifiMacQueueItem>)
{
  m_discarded = true;
}
 
void
AmpduAggregationTest::DoRun (void)
{
  /*
   * Create device and attach HT configuration.
   */
  m_device = CreateObject<WifiNetDevice> ();
  Ptr<HtConfiguration> htConfiguration = CreateObject<HtConfiguration> ();
  m_device->SetHtConfiguration (htConfiguration);
 
  /*
   * Create and configure phy layer.
   */
  m_phy = CreateObject<YansWifiPhy> ();
  Ptr<InterferenceHelper> interferenceHelper = CreateObject<InterferenceHelper> ();
  m_phy->SetInterferenceHelper (interferenceHelper);
  m_phy->SetDevice (m_device);
  m_phy->ConfigureStandard (WIFI_STANDARD_80211n);
  m_device->SetPhy (m_phy);
 
  /*
   * Create and configure manager.
   */
  m_factory = ObjectFactory ();
  m_factory.SetTypeId ("ns3::ConstantRateWifiManager");
  m_factory.Set ("DataMode", StringValue ("HtMcs7"));
  m_manager = m_factory.Create<WifiRemoteStationManager> ();
  m_manager->SetupPhy (m_phy);
  m_device->SetRemoteStationManager (m_manager);
 
  /*
   * Create and configure mac layer.
   */
  m_mac = CreateObjectWithAttributes<StaWifiMac> ("QosSupported", BooleanValue (true));
  m_mac->SetDevice (m_device);
  m_mac->SetWifiRemoteStationManager (m_manager);
  m_mac->SetAddress (Mac48Address ("00:00:00:00:00:01"));
  m_mac->ConfigureStandard (WIFI_STANDARD_80211n);
  Ptr<FrameExchangeManager> fem = m_mac->GetFrameExchangeManager ();
  Ptr<WifiProtectionManager> protectionManager = CreateObject<WifiDefaultProtectionManager> ();
  protectionManager->SetWifiMac (m_mac);
  fem->SetProtectionManager (protectionManager);
  Ptr<WifiAckManager> ackManager = CreateObject<WifiDefaultAckManager> ();
  ackManager->SetWifiMac (m_mac);
  fem->SetAckManager (ackManager);
  m_mac->SetWifiPhy (m_phy);
  m_device->SetMac (m_mac);
  m_mac->SetState (StaWifiMac::ASSOCIATED);
 
  /*
   * Configure MPDU aggregation.
   */
  m_mac->SetAttribute ("BE_MaxAmpduSize", UintegerValue (65535));
  HtCapabilities htCapabilities;
  htCapabilities.SetMaxAmpduLength (65535);
  m_manager->AddStationHtCapabilities (Mac48Address ("00:00:00:00:00:02"), htCapabilities);
  m_manager->AddStationHtCapabilities (Mac48Address ("00:00:00:00:00:03"), htCapabilities);
 
  /*
   * Create a dummy packet of 1500 bytes and fill mac header fields.
   */
  Ptr<const Packet> pkt = Create<Packet> (1500);
  Ptr<Packet> currentAggregatedPacket = Create<Packet> ();
  WifiMacHeader hdr;
  hdr.SetAddr1 (Mac48Address ("00:00:00:00:00:02"));
  hdr.SetAddr2 (Mac48Address ("00:00:00:00:00:01"));
  hdr.SetType (WIFI_MAC_QOSDATA);
  hdr.SetQosTid (0);
  hdr.SetFragmentNumber (0);
  hdr.SetNoMoreFragments ();
  hdr.SetNoRetry ();
 
  /*
   * Establish agreement.
   */
  MgtAddBaRequestHeader reqHdr;
  reqHdr.SetImmediateBlockAck ();
  reqHdr.SetTid (0);
  reqHdr.SetBufferSize (64);
  reqHdr.SetTimeout (0);
  reqHdr.SetStartingSequence (0);
  m_mac->GetBEQueue ()->GetBaManager ()->CreateAgreement (&reqHdr, hdr.GetAddr1 ());
 
  MgtAddBaResponseHeader respHdr;
  StatusCode code;
  code.SetSuccess ();
  respHdr.SetStatusCode (code);
  respHdr.SetAmsduSupport (reqHdr.IsAmsduSupported ());
  respHdr.SetImmediateBlockAck ();
  respHdr.SetTid (reqHdr.GetTid ());
  respHdr.SetBufferSize (64);
  respHdr.SetTimeout (reqHdr.GetTimeout ());
  m_mac->GetBEQueue ()->GetBaManager ()->UpdateAgreement (&respHdr, hdr.GetAddr1 (), 0);
 
  //-----------------------------------------------------------------------------------------------------
 
  /*
   * Test behavior when no other packets are in the queue
   */
  Ptr<HtFrameExchangeManager> htFem = DynamicCast<HtFrameExchangeManager> (fem);
  Ptr<MpduAggregator> mpduAggregator = htFem->GetMpduAggregator ();
 
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (pkt, hdr));
 
  Ptr<const WifiMacQueueItem> peeked = m_mac->GetBEQueue ()->PeekNextMpdu ();
  WifiTxParameters txParams;
  txParams.m_txVector = m_mac->GetWifiRemoteStationManager ()->GetDataTxVector (peeked->GetHeader ());
  Ptr<WifiMacQueueItem> item = m_mac->GetBEQueue ()->GetNextMpdu (peeked, txParams, Time::Min (), true);
 
  auto mpduList = mpduAggregator->GetNextAmpdu (item, txParams, Time::Min ());
 
  NS_TEST_EXPECT_MSG_EQ (mpduList.empty (), true, "a single packet should not result in an A-MPDU");
 
  // the packet has not been "transmitted", release its sequence number
  m_mac->m_txMiddle->SetSequenceNumberFor (&item->GetHeader ());
 
  //-----------------------------------------------------------------------------------------------------
 
  /*
   * Test behavior when 2 more packets are in the queue
   */
  Ptr<const Packet> pkt1 = Create<Packet> (1500);
  Ptr<const Packet> pkt2 = Create<Packet> (1500);
  WifiMacHeader hdr1, hdr2;
 
  hdr1.SetAddr1 (Mac48Address ("00:00:00:00:00:02"));
  hdr1.SetAddr2 (Mac48Address ("00:00:00:00:00:01"));
  hdr1.SetType (WIFI_MAC_QOSDATA);
  hdr1.SetQosTid (0);
 
  hdr2.SetAddr1 (Mac48Address ("00:00:00:00:00:02"));
  hdr2.SetAddr2 (Mac48Address ("00:00:00:00:00:01"));
  hdr2.SetType (WIFI_MAC_QOSDATA);
  hdr2.SetQosTid (0);
 
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (pkt1, hdr1));
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (pkt2, hdr2));
 
  item = m_mac->GetBEQueue ()->GetNextMpdu (peeked, txParams, Time::Min (), true);
  mpduList = mpduAggregator->GetNextAmpdu (item, txParams, Time::Min ());
 
  NS_TEST_EXPECT_MSG_EQ (mpduList.empty (), false, "MPDU aggregation failed");
 
  Ptr<WifiPsdu> psdu = Create<WifiPsdu> (mpduList);
  htFem->DequeuePsdu (psdu);
 
  NS_TEST_EXPECT_MSG_EQ (psdu->GetSize (), 4606, "A-MPDU size is not correct");
  NS_TEST_EXPECT_MSG_EQ (mpduList.size (), 3, "A-MPDU should contain 3 MPDUs");
  NS_TEST_EXPECT_MSG_EQ (m_mac->GetBEQueue ()->GetWifiMacQueue ()->GetNPackets (), 0, "queue should be empty");
 
  for (uint32_t i = 0; i < psdu->GetNMpdus (); i++)
    {
      NS_TEST_EXPECT_MSG_EQ (psdu->GetHeader (i).GetSequenceNumber (), i, "wrong sequence number");
    }
 
  //-----------------------------------------------------------------------------------------------------
 
  /*
   * Test behavior when the 802.11n station and another non-QoS station are associated to the AP.
   * The AP sends an A-MPDU to the 802.11n station followed by the last retransmission of a non-QoS data frame to the non-QoS station.
   * This is used to reproduce bug 2224.
   */
  pkt1 = Create<Packet> (1500);
  pkt2 = Create<Packet> (1500);
  hdr1.SetAddr1 (Mac48Address ("00:00:00:00:00:02"));
  hdr1.SetAddr2 (Mac48Address ("00:00:00:00:00:01"));
  hdr1.SetType (WIFI_MAC_QOSDATA);
  hdr1.SetQosTid (0);
  hdr1.SetSequenceNumber (3);
  hdr2.SetAddr1 (Mac48Address ("00:00:00:00:00:03"));
  hdr2.SetAddr2 (Mac48Address ("00:00:00:00:00:01"));
  hdr2.SetType (WIFI_MAC_QOSDATA);
  hdr2.SetQosTid (0);
 
  Ptr<const Packet> pkt3 = Create<Packet> (1500);
  WifiMacHeader hdr3;
  hdr3.SetSequenceNumber (0);
  hdr3.SetAddr1 (Mac48Address ("00:00:00:00:00:03"));
  hdr3.SetAddr2 (Mac48Address ("00:00:00:00:00:01"));
  hdr3.SetType (WIFI_MAC_QOSDATA);
  hdr3.SetQosTid (0);
 
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (pkt1, hdr1));
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (pkt2, hdr2));
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (pkt3, hdr3));
 
  peeked = m_mac->GetBEQueue ()->PeekNextMpdu ();
  txParams.Clear ();
  txParams.m_txVector = m_mac->GetWifiRemoteStationManager ()->GetDataTxVector (peeked->GetHeader ());
  item = m_mac->GetBEQueue ()->GetNextMpdu (peeked, txParams, Time::Min (), true);
 
  mpduList = mpduAggregator->GetNextAmpdu (item, txParams, Time::Min ());
 
  NS_TEST_EXPECT_MSG_EQ (mpduList.empty (), true, "a single packet for this destination should not result in an A-MPDU");
  // dequeue the MPDU
  htFem->DequeueMpdu (item);
 
  peeked = m_mac->GetBEQueue ()->PeekNextMpdu ();
  txParams.Clear ();
  txParams.m_txVector = m_mac->GetWifiRemoteStationManager ()->GetDataTxVector (peeked->GetHeader ());
  item = m_mac->GetBEQueue ()->GetNextMpdu (peeked, txParams, Time::Min (), true);
 
  mpduList = mpduAggregator->GetNextAmpdu (item, txParams, Time::Min ());
 
  NS_TEST_EXPECT_MSG_EQ (mpduList.empty (), true, "no MPDU aggregation should be performed if there is no agreement");
 
  m_manager->SetMaxSsrc (0); //set to 0 in order to fake that the maximum number of retries has been reached
  m_mac->TraceConnectWithoutContext ("DroppedMpdu", MakeCallback (&AmpduAggregationTest::MpduDiscarded, this));
  htFem->m_dcf = m_mac->GetBEQueue ();
  htFem->NormalAckTimeout (item, txParams.m_txVector);
 
  NS_TEST_EXPECT_MSG_EQ (m_discarded, true, "packet should be discarded");
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Flush ();
 
  Simulator::Destroy ();
 
  m_manager->Dispose ();
  m_manager = 0;
 
  m_device->Dispose ();
  m_device = 0;
 
  htConfiguration = 0;
}
 
class TwoLevelAggregationTest : public TestCase
{
public:
  TwoLevelAggregationTest ();
 
private:
  void DoRun (void) override;
  Ptr<WifiNetDevice> m_device; 
  Ptr<StaWifiMac> m_mac; 
  Ptr<YansWifiPhy> m_phy; 
  Ptr<WifiRemoteStationManager> m_manager; 
  ObjectFactory m_factory; 
};
 
TwoLevelAggregationTest::TwoLevelAggregationTest ()
  : TestCase ("Check the correctness of two-level aggregation operations")
{
}
 
void
TwoLevelAggregationTest::DoRun (void)
{
  /*
   * Create device and attach HT configuration.
   */
  m_device = CreateObject<WifiNetDevice> ();
  m_device->SetStandard (WIFI_STANDARD_80211n);
  Ptr<HtConfiguration> htConfiguration = CreateObject<HtConfiguration> ();
  m_device->SetHtConfiguration (htConfiguration);
 
  /*
   * Create and configure phy layer.
   */
  m_phy = CreateObject<YansWifiPhy> ();
  Ptr<InterferenceHelper> interferenceHelper = CreateObject<InterferenceHelper> ();
  m_phy->SetInterferenceHelper (interferenceHelper);
  m_phy->SetDevice (m_device);
  m_phy->ConfigureStandard (WIFI_STANDARD_80211n);
  m_device->SetPhy (m_phy);
 
  /*
   * Create and configure manager.
   */
  m_factory = ObjectFactory ();
  m_factory.SetTypeId ("ns3::ConstantRateWifiManager");
  m_factory.Set ("DataMode", StringValue ("HtMcs7"));
  m_manager = m_factory.Create<WifiRemoteStationManager> ();
  m_manager->SetupPhy (m_phy);
  m_device->SetRemoteStationManager (m_manager);
 
  /*
   * Create and configure mac layer.
   */
  m_mac = CreateObjectWithAttributes<StaWifiMac> ("QosSupported", BooleanValue (true));
  m_mac->SetDevice (m_device);
  m_mac->SetWifiRemoteStationManager (m_manager);
  m_mac->SetAddress (Mac48Address ("00:00:00:00:00:01"));
  m_mac->ConfigureStandard (WIFI_STANDARD_80211n);
  Ptr<FrameExchangeManager> fem = m_mac->GetFrameExchangeManager ();
  Ptr<WifiProtectionManager> protectionManager = CreateObject<WifiDefaultProtectionManager> ();
  protectionManager->SetWifiMac (m_mac);
  fem->SetProtectionManager (protectionManager);
  Ptr<WifiAckManager> ackManager = CreateObject<WifiDefaultAckManager> ();
  ackManager->SetWifiMac (m_mac);
  fem->SetAckManager (ackManager);
  m_mac->SetWifiPhy (m_phy);
  m_device->SetMac (m_mac);
  m_mac->SetState (StaWifiMac::ASSOCIATED);
 
  /*
   * Configure aggregation.
   */
  m_mac->SetAttribute ("BE_MaxAmsduSize", UintegerValue (4095));
  m_mac->SetAttribute ("BE_MaxAmpduSize", UintegerValue (65535));
  HtCapabilities htCapabilities;
  htCapabilities.SetMaxAmsduLength (7935);
  htCapabilities.SetMaxAmpduLength (65535);
  m_manager->AddStationHtCapabilities (Mac48Address ("00:00:00:00:00:02"), htCapabilities);
 
  /*
   * Create dummy packets of 1500 bytes and fill mac header fields that will be used for the tests.
   */
  Ptr<const Packet> pkt = Create<Packet> (1500);
  WifiMacHeader hdr;
  hdr.SetAddr1 (Mac48Address ("00:00:00:00:00:02"));
  hdr.SetAddr2 (Mac48Address ("00:00:00:00:00:01"));
  hdr.SetType (WIFI_MAC_QOSDATA);
  hdr.SetQosTid (0);
 
  //-----------------------------------------------------------------------------------------------------
 
  /*
   * Test MSDU and MPDU aggregation. Three MSDUs are in the queue and the maximum A-MSDU size
   * is such that only two MSDUs can be aggregated. Therefore, the first MPDU we get contains
   * an A-MSDU of 2 MSDUs.
   */
  Ptr<HtFrameExchangeManager> htFem = DynamicCast<HtFrameExchangeManager> (fem);
  Ptr<MsduAggregator> msduAggregator = htFem->GetMsduAggregator ();
  Ptr<MpduAggregator> mpduAggregator = htFem->GetMpduAggregator ();
 
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (Create<Packet> (1500), hdr));
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (Create<Packet> (1500), hdr));
  m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (Create<Packet> (1500), hdr));
 
  Ptr<const WifiMacQueueItem> peeked = m_mac->GetBEQueue ()->PeekNextMpdu ();
  WifiTxParameters txParams;
  txParams.m_txVector = m_mac->GetWifiRemoteStationManager ()->GetDataTxVector (peeked->GetHeader ());
  htFem->TryAddMpdu (peeked, txParams, Time::Min ());
  Ptr<WifiMacQueueItem> item = msduAggregator->GetNextAmsdu (peeked, txParams, Time::Min ());
 
  bool result = (item != 0);
  NS_TEST_EXPECT_MSG_EQ (result, true, "aggregation failed");
  NS_TEST_EXPECT_MSG_EQ (item->GetPacketSize (), 3030, "wrong packet size");
 
  // dequeue the MSDUs
  htFem->DequeueMpdu (item);
 
  NS_TEST_EXPECT_MSG_EQ (m_mac->GetBEQueue ()->GetWifiMacQueue ()->GetNPackets (), 1,
                         "Unexpected number of MSDUs left in the EDCA queue");
 
  //-----------------------------------------------------------------------------------------------------
 
  /*
   * A-MSDU aggregation fails when there is just one MSDU in the queue.
   */
 
  peeked = m_mac->GetBEQueue ()->PeekNextMpdu ();
  txParams.Clear ();
  txParams.m_txVector = m_mac->GetWifiRemoteStationManager ()->GetDataTxVector (peeked->GetHeader ());
  htFem->TryAddMpdu (peeked, txParams, Time::Min ());
  item = msduAggregator->GetNextAmsdu (peeked, txParams, Time::Min ());
 
  NS_TEST_EXPECT_MSG_EQ ((item == 0), true, "A-MSDU aggregation did not fail");
 
  htFem->DequeueMpdu (peeked);
 
  NS_TEST_EXPECT_MSG_EQ (m_mac->GetBEQueue ()->GetWifiMacQueue ()->GetNPackets (), 0, "queue should be empty");
 
  //-----------------------------------------------------------------------------------------------------
 
  /*
   * Aggregation of MPDUs is stopped to prevent that the PPDU duration exceeds the TXOP limit.
   * In this test, the VI AC is used, which has a default TXOP limit of 3008 microseconds.
   */
 
  // Establish agreement.
  uint8_t tid = 5;
  MgtAddBaRequestHeader reqHdr;
  reqHdr.SetImmediateBlockAck ();
  reqHdr.SetTid (tid);
  reqHdr.SetBufferSize (64);
  reqHdr.SetTimeout (0);
  reqHdr.SetStartingSequence (0);
  m_mac->GetVIQueue ()->GetBaManager ()->CreateAgreement (&reqHdr, hdr.GetAddr1 ());
 
  MgtAddBaResponseHeader respHdr;
  StatusCode code;
  code.SetSuccess ();
  respHdr.SetStatusCode (code);
  respHdr.SetAmsduSupport (reqHdr.IsAmsduSupported ());
  respHdr.SetImmediateBlockAck ();
  respHdr.SetTid (reqHdr.GetTid ());
  respHdr.SetBufferSize (64);
  respHdr.SetTimeout (reqHdr.GetTimeout ());
  m_mac->GetVIQueue ()->GetBaManager ()->UpdateAgreement (&respHdr, hdr.GetAddr1 (), 0);
 
  m_mac->SetAttribute ("VI_MaxAmsduSize", UintegerValue (3050));  // max 2 MSDUs per A-MSDU
  m_mac->SetAttribute ("VI_MaxAmpduSize", UintegerValue (65535));
  m_manager->SetAttribute ("DataMode", StringValue ("HtMcs2"));  // 19.5Mbps
 
  hdr.SetQosTid (tid);
 
  // Add 10 MSDUs to the EDCA queue
  for (uint8_t i = 0; i < 10; i++)
    {
      m_mac->GetVIQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (Create<Packet> (1300), hdr));
    }
 
  peeked = m_mac->GetVIQueue ()->PeekNextMpdu ();
  txParams.Clear ();
  txParams.m_txVector = m_mac->GetWifiRemoteStationManager ()->GetDataTxVector (peeked->GetHeader ());
  Time txopLimit = m_mac->GetVIQueue ()->GetTxopLimit ();   // 3.008 ms
 
  // Compute the first MPDU to be aggregated in an A-MPDU. It must contain an A-MSDU
  // aggregating two MSDUs
  item = m_mac->GetVIQueue ()->GetNextMpdu (peeked, txParams, txopLimit, true);
 
  NS_TEST_EXPECT_MSG_EQ (std::distance (item->begin (), item->end ()), 2, "There must be 2 MSDUs in the A-MSDU");
 
  auto mpduList = mpduAggregator->GetNextAmpdu (item, txParams, txopLimit);
 
  // The maximum number of bytes that can be transmitted in a TXOP is (approximately, as we
  // do not consider that the preamble is transmitted at a different rate):
  // 19.5 Mbps * 3.008 ms = 7332 bytes
  // Given that the max A-MSDU size is set to 3050, an A-MSDU will contain two MSDUs and have
  // a size of 2 * 1300 (MSDU size) + 2 * 14 (A-MSDU subframe header size) + 2 (one padding field) = 2630 bytes
  // Hence, we expect that the A-MPDU will consist of:
  // - 2 MPDUs containing each an A-MSDU. The size of each MPDU is 2630 (A-MSDU) + 30 (header+trailer) = 2660
  // - 1 MPDU containing a single MSDU. The size of such MPDU is 1300 (MSDU) + 30 (header+trailer) = 1330
  // The size of the A-MPDU is 4 + 2660 + 4 + 2660 + 4 + 1330 = 6662
  NS_TEST_EXPECT_MSG_EQ (mpduList.empty (), false, "aggregation failed");
  NS_TEST_EXPECT_MSG_EQ (mpduList.size (), 3, "Unexpected number of MPDUs in the A-MPDU");
  NS_TEST_EXPECT_MSG_EQ (mpduList.at (0)->GetSize (), 2660, "Unexpected size of the first MPDU");
  NS_TEST_EXPECT_MSG_EQ (mpduList.at (1)->GetSize (), 2660, "Unexpected size of the second MPDU");
  NS_TEST_EXPECT_MSG_EQ (mpduList.at (2)->GetSize (), 1330, "Unexpected size of the first MPDU");
 
  Ptr<WifiPsdu> psdu = Create<WifiPsdu> (mpduList);
  htFem->DequeuePsdu (psdu);
 
  NS_TEST_EXPECT_MSG_EQ (m_mac->GetVIQueue ()->GetWifiMacQueue ()->GetNPackets (), 5,
                         "Unexpected number of MSDUs left in the EDCA queue");
 
  NS_TEST_EXPECT_MSG_EQ (psdu->GetSize (), 6662, "Unexpected size of the A-MPDU");
 
  Simulator::Destroy ();
 
  m_device->Dispose ();
  m_device = 0;
  htConfiguration = 0;
}
 
class HeAggregationTest : public TestCase
{
public:
  HeAggregationTest ();
 
private:
  void DoRun (void) override;
  void DoRunSubTest (uint16_t bufferSize);
  Ptr<WifiNetDevice> m_device; 
  Ptr<StaWifiMac> m_mac; 
  Ptr<YansWifiPhy> m_phy; 
  Ptr<WifiRemoteStationManager> m_manager; 
  ObjectFactory m_factory; 
};
 
HeAggregationTest::HeAggregationTest ()
  : TestCase ("Check the correctness of 802.11ax aggregation operations")
{
}
 
void
HeAggregationTest::DoRunSubTest (uint16_t bufferSize)
{
  /*
   * Create device and attach configurations.
   */
  m_device = CreateObject<WifiNetDevice> ();
  Ptr<HtConfiguration> htConfiguration = CreateObject<HtConfiguration> ();
  m_device->SetHtConfiguration (htConfiguration);
  Ptr<VhtConfiguration> vhtConfiguration = CreateObject<VhtConfiguration> ();
  m_device->SetVhtConfiguration (vhtConfiguration);
  Ptr<HeConfiguration> heConfiguration = CreateObject<HeConfiguration> ();
  m_device->SetHeConfiguration (heConfiguration);
 
  /*
   * Create and configure phy layer.
   */
  m_phy = CreateObject<YansWifiPhy> ();
  Ptr<InterferenceHelper> interferenceHelper = CreateObject<InterferenceHelper> ();
  m_phy->SetInterferenceHelper (interferenceHelper);
  m_phy->SetDevice (m_device);
  m_phy->ConfigureStandard (WIFI_STANDARD_80211ax);
  m_device->SetPhy (m_phy);
 
  /*
   * Create and configure manager.
   */
  m_factory = ObjectFactory ();
  m_factory.SetTypeId ("ns3::ConstantRateWifiManager");
  m_factory.Set ("DataMode", StringValue ("HeMcs11"));
  m_manager = m_factory.Create<WifiRemoteStationManager> ();
  m_manager->SetupPhy (m_phy);
  m_device->SetRemoteStationManager (m_manager);
 
  /*
   * Create and configure mac layer.
   */
  m_mac = CreateObjectWithAttributes<StaWifiMac> ("QosSupported", BooleanValue (true));
  m_mac->SetDevice (m_device);
  m_mac->SetWifiRemoteStationManager (m_manager);
  m_mac->SetAddress (Mac48Address ("00:00:00:00:00:01"));
  m_mac->ConfigureStandard (WIFI_STANDARD_80211ax);
  Ptr<FrameExchangeManager> fem = m_mac->GetFrameExchangeManager ();
  Ptr<WifiProtectionManager> protectionManager = CreateObject<WifiDefaultProtectionManager> ();
  protectionManager->SetWifiMac (m_mac);
  fem->SetProtectionManager (protectionManager);
  Ptr<WifiAckManager> ackManager = CreateObject<WifiDefaultAckManager> ();
  ackManager->SetWifiMac (m_mac);
  fem->SetAckManager (ackManager);
  m_mac->SetWifiPhy (m_phy);
  m_device->SetMac (m_mac);
  m_mac->SetState (StaWifiMac::ASSOCIATED);
 
  /*
   * Configure aggregation.
   */
  HeCapabilities heCapabilities;
  m_manager->AddStationHeCapabilities (Mac48Address ("00:00:00:00:00:02"), heCapabilities);
 
  /*
   * Fill mac header fields.
   */
  WifiMacHeader hdr;
  hdr.SetAddr1 (Mac48Address ("00:00:00:00:00:02"));
  hdr.SetAddr2 (Mac48Address ("00:00:00:00:00:01"));
  hdr.SetType (WIFI_MAC_QOSDATA);
  hdr.SetQosTid (0);
  uint16_t sequence = m_mac->m_txMiddle->PeekNextSequenceNumberFor (&hdr);
  hdr.SetSequenceNumber (sequence);
  hdr.SetFragmentNumber (0);
  hdr.SetNoMoreFragments ();
  hdr.SetNoRetry ();
 
  /*
   * Establish agreement.
   */
  MgtAddBaRequestHeader reqHdr;
  reqHdr.SetImmediateBlockAck ();
  reqHdr.SetTid (0);
  reqHdr.SetBufferSize (bufferSize);
  reqHdr.SetTimeout (0);
  reqHdr.SetStartingSequence (0);
  m_mac->GetBEQueue ()->GetBaManager ()->CreateAgreement (&reqHdr, hdr.GetAddr1 ());
 
  MgtAddBaResponseHeader respHdr;
  StatusCode code;
  code.SetSuccess ();
  respHdr.SetStatusCode (code);
  respHdr.SetAmsduSupport (reqHdr.IsAmsduSupported ());
  respHdr.SetImmediateBlockAck ();
  respHdr.SetTid (reqHdr.GetTid ());
  respHdr.SetBufferSize (bufferSize);
  respHdr.SetTimeout (reqHdr.GetTimeout ());
  m_mac->GetBEQueue ()->GetBaManager ()->UpdateAgreement (&respHdr, hdr.GetAddr1 (), 0);
 
  /*
   * Test behavior when 300 packets are ready for transmission but negociated buffer size is 64
   */
  Ptr<HtFrameExchangeManager> htFem = DynamicCast<HtFrameExchangeManager> (fem);
  Ptr<MpduAggregator> mpduAggregator = htFem->GetMpduAggregator ();
 
  for (uint16_t i = 0; i < 300; i++)
    {
      Ptr<const Packet> pkt = Create<Packet> (100);
      WifiMacHeader hdr;
 
      hdr.SetAddr1 (Mac48Address ("00:00:00:00:00:02"));
      hdr.SetAddr2 (Mac48Address ("00:00:00:00:00:01"));
      hdr.SetType (WIFI_MAC_QOSDATA);
      hdr.SetQosTid (0);
 
      m_mac->GetBEQueue ()->GetWifiMacQueue ()->Enqueue (Create<WifiMacQueueItem> (pkt, hdr));
  }
 
  Ptr<const WifiMacQueueItem> peeked = m_mac->GetBEQueue ()->PeekNextMpdu ();
  WifiTxParameters txParams;
  txParams.m_txVector = m_mac->GetWifiRemoteStationManager ()->GetDataTxVector (peeked->GetHeader ());
  Ptr<WifiMacQueueItem> item = m_mac->GetBEQueue ()->GetNextMpdu (peeked, txParams, Time::Min (), true);
 
  auto mpduList = mpduAggregator->GetNextAmpdu (item, txParams, Time::Min ());
  Ptr<WifiPsdu> psdu = Create<WifiPsdu> (mpduList);
  htFem->DequeuePsdu (psdu);
 
  NS_TEST_EXPECT_MSG_EQ (mpduList.empty (), false, "MPDU aggregation failed");
  NS_TEST_EXPECT_MSG_EQ (mpduList.size (), bufferSize, "A-MPDU should countain " << bufferSize << " MPDUs");
  uint16_t expectedRemainingPacketsInQueue = 300 - bufferSize;
  NS_TEST_EXPECT_MSG_EQ (m_mac->GetBEQueue ()->GetWifiMacQueue ()->GetNPackets (), expectedRemainingPacketsInQueue, "queue should contain 300 - "<< bufferSize << " = "<< expectedRemainingPacketsInQueue << " packets");
 
  Simulator::Destroy ();
 
  m_manager->Dispose ();
  m_manager = 0;
 
  m_device->Dispose ();
  m_device = 0;
 
  htConfiguration = 0;
  vhtConfiguration = 0;
  heConfiguration = 0;
}
 
void
HeAggregationTest::DoRun ()
{
  DoRunSubTest (64);
  DoRunSubTest (256);
}
 
class PreservePacketsInAmpdus : public TestCase
{
public:
  PreservePacketsInAmpdus ();
  virtual ~PreservePacketsInAmpdus ();
 
  void DoRun (void) override;
 
 
private:
  std::list<Ptr<const Packet>> m_packetList; 
  std::vector<std::size_t> m_nMpdus;         
  std::vector<std::size_t> m_nMsdus;         
 
  void NotifyMacTransmit (Ptr<const Packet> packet);
  void NotifyPsduForwardedDown (WifiConstPsduMap psduMap, WifiTxVector txVector, double txPowerW);
  void NotifyMacForwardUp (Ptr<const Packet> p);
};
 
PreservePacketsInAmpdus::PreservePacketsInAmpdus ()
  : TestCase ("Test case to check that the Wifi Mac forwards up the same packets received at sender side.")
{
}
 
PreservePacketsInAmpdus::~PreservePacketsInAmpdus ()
{
}
 
void
PreservePacketsInAmpdus::NotifyMacTransmit (Ptr<const Packet> packet)
{
  m_packetList.push_back (packet);
}
 
void
PreservePacketsInAmpdus::NotifyPsduForwardedDown (WifiConstPsduMap psduMap, WifiTxVector txVector, double txPowerW)
{
  NS_TEST_EXPECT_MSG_EQ ((psduMap.size () == 1 && psduMap.begin ()->first == SU_STA_ID),
                         true, "No DL MU PPDU expected");
 
  if (!psduMap[SU_STA_ID]->GetHeader (0).IsQosData ())
    {
      return;
    }
 
  m_nMpdus.push_back (psduMap[SU_STA_ID]->GetNMpdus ());
 
  for (auto& mpdu : *PeekPointer (psduMap[SU_STA_ID]))
    {
      std::size_t dist = std::distance (mpdu->begin (), mpdu->end ());
      // the list of aggregated MSDUs is empty if the MPDU includes a non-aggregated MSDU
      m_nMsdus.push_back (dist > 0 ? dist : 1);
    }
}
 
void
PreservePacketsInAmpdus::NotifyMacForwardUp (Ptr<const Packet> p)
{
  auto it = std::find (m_packetList.begin (), m_packetList.end (), p);
  NS_TEST_EXPECT_MSG_EQ ((it != m_packetList.end ()), true, "Packet being forwarded up not found");
  m_packetList.erase (it);
}
 
void
PreservePacketsInAmpdus::DoRun (void)
{
  NodeContainer wifiStaNode;
  wifiStaNode.Create (1);
 
  NodeContainer wifiApNode;
  wifiApNode.Create (1);
 
  YansWifiChannelHelper channel = YansWifiChannelHelper::Default ();
  YansWifiPhyHelper phy;
  phy.SetChannel (channel.Create ());
 
  WifiHelper wifi;
  wifi.SetStandard (WIFI_STANDARD_80211n);
  wifi.SetRemoteStationManager ("ns3::IdealWifiManager");
 
  WifiMacHelper mac;
  Ssid ssid = Ssid ("ns-3-ssid");
  mac.SetType ("ns3::StaWifiMac",
               "BE_MaxAmsduSize", UintegerValue (4500),
               "BE_MaxAmpduSize", UintegerValue (7500),
               "Ssid", SsidValue (ssid),
               /* setting blockack threshold for sta's BE queue */
               "BE_BlockAckThreshold", UintegerValue (2),
               "ActiveProbing", BooleanValue (false));
 
  NetDeviceContainer staDevices;
  staDevices = wifi.Install (phy, mac, wifiStaNode);
 
  mac.SetType ("ns3::ApWifiMac",
               "Ssid", SsidValue (ssid),
               "BeaconGeneration", BooleanValue (true));
 
  NetDeviceContainer apDevices;
  apDevices = wifi.Install (phy, mac, wifiApNode);
 
  MobilityHelper mobility;
  Ptr<ListPositionAllocator> positionAlloc = CreateObject<ListPositionAllocator> ();
 
  positionAlloc->Add (Vector (0.0, 0.0, 0.0));
  positionAlloc->Add (Vector (1.0, 0.0, 0.0));
  mobility.SetPositionAllocator (positionAlloc);
 
  mobility.SetMobilityModel ("ns3::ConstantPositionMobilityModel");
  mobility.Install (wifiApNode);
  mobility.Install (wifiStaNode);
 
  Ptr<WifiNetDevice> ap_device = DynamicCast<WifiNetDevice> (apDevices.Get (0));
  Ptr<WifiNetDevice> sta_device = DynamicCast<WifiNetDevice> (staDevices.Get (0));
 
  PacketSocketAddress socket;
  socket.SetSingleDevice (sta_device->GetIfIndex ());
  socket.SetPhysicalAddress (ap_device->GetAddress ());
  socket.SetProtocol (1);
 
  // install packet sockets on nodes.
  PacketSocketHelper packetSocket;
  packetSocket.Install (wifiStaNode);
  packetSocket.Install (wifiApNode);
 
  Ptr<PacketSocketClient> client = CreateObject<PacketSocketClient> ();
  client->SetAttribute ("PacketSize", UintegerValue (1000));
  client->SetAttribute ("MaxPackets", UintegerValue (8));
  client->SetAttribute ("Interval", TimeValue (Seconds (1)));
  client->SetRemote (socket);
  wifiStaNode.Get (0)->AddApplication (client);
  client->SetStartTime (Seconds (1));
  client->SetStopTime (Seconds (3.0));
  Simulator::Schedule (Seconds (1.5), &PacketSocketClient::SetAttribute, client,
                       "Interval", TimeValue (MicroSeconds (0)));
 
  Ptr<PacketSocketServer> server = CreateObject<PacketSocketServer> ();
  server->SetLocal (socket);
  wifiApNode.Get (0)->AddApplication (server);
  server->SetStartTime (Seconds (0.0));
  server->SetStopTime (Seconds (4.0));
 
  sta_device->GetMac ()->TraceConnectWithoutContext ("MacTx",
    MakeCallback (&PreservePacketsInAmpdus::NotifyMacTransmit, this));
  sta_device->GetPhy ()->TraceConnectWithoutContext ("PhyTxPsduBegin",
    MakeCallback (&PreservePacketsInAmpdus::NotifyPsduForwardedDown, this));
  ap_device->GetMac ()->TraceConnectWithoutContext ("MacRx",
    MakeCallback (&PreservePacketsInAmpdus::NotifyMacForwardUp, this));
 
  Simulator::Stop (Seconds (5));
  Simulator::Run ();
 
  Simulator::Destroy ();
 
  // Two packets are transmitted. The first one is an MPDU containing a single MSDU.
  // The second one is an A-MPDU containing two MPDUs: the first MPDU contains 4 MSDUs
  // and the second MPDU contains 3 MSDUs
  NS_TEST_EXPECT_MSG_EQ (m_nMpdus.size (), 2, "Unexpected number of transmitted packets");
  NS_TEST_EXPECT_MSG_EQ (m_nMsdus.size (), 3, "Unexpected number of transmitted MPDUs");
  NS_TEST_EXPECT_MSG_EQ (m_nMpdus[0], 1, "Unexpected number of MPDUs in the first A-MPDU");
  NS_TEST_EXPECT_MSG_EQ (m_nMsdus[0], 1, "Unexpected number of MSDUs in the first MPDU");
  NS_TEST_EXPECT_MSG_EQ (m_nMpdus[1], 2, "Unexpected number of MPDUs in the second A-MPDU");
  NS_TEST_EXPECT_MSG_EQ (m_nMsdus[1], 4, "Unexpected number of MSDUs in the second MPDU");
  NS_TEST_EXPECT_MSG_EQ (m_nMsdus[2], 3, "Unexpected number of MSDUs in the third MPDU");
  // All the packets must have been forwarded up at the receiver
  NS_TEST_EXPECT_MSG_EQ (m_packetList.empty (), true, "Some packets have not been forwarded up");
}
 
class WifiAggregationTestSuite : public TestSuite
{
public:
  WifiAggregationTestSuite ();
};
 
WifiAggregationTestSuite::WifiAggregationTestSuite ()
  : TestSuite ("wifi-aggregation", UNIT)
{
  AddTestCase (new AmpduAggregationTest, TestCase::QUICK);
  AddTestCase (new TwoLevelAggregationTest, TestCase::QUICK);
  AddTestCase (new HeAggregationTest, TestCase::QUICK);
  AddTestCase (new PreservePacketsInAmpdus, TestCase::QUICK);
}
 
static WifiAggregationTestSuite g_wifiAggregationTestSuite;