eden-sim/contrib/tsn/model/tsn-net-device.cc

#include "tsn-net-device.h"

#include "ns3/log.h"
#include "ns3/packet.h"
#include "ns3/queue.h"
#include "ns3/ethernet-trailer.h"
#include "ns3/names.h"
#include "ns3/timestamp-tag.h"
#include "ns3/simulator.h"
#include "ns3/callback.h"
#include "ns3/error-model.h"

#include "ns3/ethernet-net-device.h"
#include "ns3/ethernet-channel.h"
#include "ns3/ethernet-header2.h"
#include "ns3/tsn-transmission-selection-algo.h"
#include "ns3/tas.h"
#include "ns3/transmission-gate.h"
#include "psfp-stream-filter-instance.h"
#include "psfp-flow-meter-instance.h"

namespace ns3
{

NS_LOG_COMPONENT_DEFINE("TsnNetDevice");

NS_OBJECT_ENSURE_REGISTERED(TsnNetDevice);

TypeId
TsnNetDevice::GetTypeId()
{
    static TypeId tid =
        TypeId("ns3::TsnNetDevice")
            .SetParent<EthernetNetDevice>()
            .SetGroupName("Tsn")
            .AddConstructor<TsnNetDevice>()
            .AddTraceSource("FrerDrop",
                            "Trace source indicating a packet was drop "
                            "by FRER recovery function",
                            MakeTraceSourceAccessor(&TsnNetDevice::m_frerDropTrace),
                            "ns3::Packet::TracedCallback")
            .AddTraceSource("MaxSDUSizeFilterDrop",
                            "Trace source indicating a packet was drop "
                            "by the maxSDUSize filter",
                            MakeTraceSourceAccessor(&TsnNetDevice::m_maxSDUSizeFilterDropTrace),
                            "ns3::Packet::TracedCallback")
            .AddTraceSource("REDFrameDrop",
                            "Trace source indicating a packet was drop "
                            "by the flow meter",
                            MakeTraceSourceAccessor(&TsnNetDevice::m_REDFrameDropTrace),
                            "ns3::Packet::TracedCallback");

    return tid;
}


TsnNetDevice::TsnNetDevice(): EthernetNetDevice()
{
  NS_LOG_FUNCTION(this);
  m_tas = CreateObject<Tas>();
  m_tas->SetTsnNetDevice(this);
}


TsnNetDevice::~TsnNetDevice()
{
  NS_LOG_FUNCTION(this);
}

void
TsnNetDevice::SetNode(Ptr<TsnNode> node)
{
  m_node = node;
}

void
TsnNetDevice::SetQueue(Ptr<Queue<Packet>> q)
{
    NS_LOG_FUNCTION(this << q);
    Ptr<TsnTransmissionSelectionAlgo> tsa = CreateObject<TsnTransmissionSelectionAlgo>();
    tsa->SetQueue(q);
    tsa->SetTsnNetDevice(this);
    SetQueue(q, tsa);
}

void
TsnNetDevice::SetQueue(Ptr<Queue<Packet>> q, Ptr<TsnTransmissionSelectionAlgo> tsa)
{
    NS_LOG_FUNCTION(this << q);
    tsa->SetQueue(q);
    m_queues.insert(m_queues.end(),q);
    m_tas->AddTransmissionGate();
    m_tas->AddTsa(tsa);
    m_transmissionSelectionAlgos.insert(m_transmissionSelectionAlgos.end(), tsa);
}

void
TsnNetDevice::UpdateQueue(uint32_t queue_id, Ptr<Queue<Packet>> q, Ptr<TsnTransmissionSelectionAlgo> tsa)
{
    NS_LOG_FUNCTION(this << q);
    NS_ASSERT(queue_id < m_queues.size());
    NS_ASSERT(queue_id < m_transmissionSelectionAlgos.size());
    tsa->SetQueue(q);
    m_tas->AddTransmissionGate();
    m_tas->AddTsa(tsa);
    m_queues[queue_id] = q;
    m_transmissionSelectionAlgos[queue_id] = tsa;
}

int
TsnNetDevice::TransmitSelection()
{
  NS_LOG_FUNCTION(this);
  //Udpate Transmission selection algo states (e.g update cbs credit)
  for (int i = m_queues.size(); i --> 0; )
  {
    m_transmissionSelectionAlgos[i]->Update();
  }

  for (int i = m_queues.size(); i --> 0; )
  {
      if(!m_queues[i]->IsEmpty() && m_tas->IsGateOpen(i))
      {
        if (m_transmissionSelectionAlgos[i]->IsReadyToTransmit())
        {
          if(m_tas->IsEnable())
          {
            Ptr<const Packet> p = m_queues[i]->Peek();
            if(m_tas->IsSendable(p, m_bps, m_preambleAndSFDGap, m_interframeGap, m_mtu))
            {
              return(i);
            }
          }
          else
          {
            return(i);
          }
        }
      }
  }
  return(-1);
}


bool
TsnNetDevice::SendFrom(Ptr<Packet> packet,
                                const Address& source,
                                const Address& dest,
                                uint16_t ethertype)
{
  NS_LOG_FUNCTION(this);

  Time hardwareLatency = Time(0);

  // Stream identification in-facing output
  std::vector<Ptr<StreamIdEntry>> streamIdentityTable = GetNode()->GetStreamIdentityTable();
  for (uint16_t i = 0; i < streamIdentityTable.size(); i++){
    if (streamIdentityTable[i]->Match(this, true, false, packet)){
        uint32_t streamHandle = streamIdentityTable[i]->GetStreamHandle();
        hardwareLatency += streamIdentityTable[i]->GetHardwareLatency();

        //FRER
        // NS_LOG_INFO( "Stream handle of Pkt #"<<packet->GetUid() << " on output : " << streamHandle);
        bool isSeqNumber = false;
        uint16_t seqNumber = 0;
        //Sequence decode => extract RTAG if this function is enable for this stream handle
        std::vector<Ptr<SequenceEncodeDecodeFunction>> seqEncTable = GetNode()->GetSequenceEncodeDecodeTable();
        for (uint32_t i = 0; i < seqEncTable.size(); i++)
        {
          if(seqEncTable[i]->IsApplicable(streamHandle, this, false))
          {
            isSeqNumber = true;
            seqNumber = seqEncTable[i]->Decode(packet);
            break;
          }
        }

        //Individual Recovery if this function is enable for this stream handle
        //TODO
        //Sequence Recovery if this function is enable for this stream handle
        std::vector<Ptr<SequenceRecoveryFunction>> seqRcvyTable = GetNode()->GetSequenceRecoveryTable();
        for (uint32_t i = 0; i < seqRcvyTable.size(); i++)
        {
          bool IsApplicable(uint32_t streamHandle, Ptr<TsnNetDevice> port, bool direction, bool hasSeqNumber, bool individualRecovery);
          if(seqRcvyTable[i]->IsApplicable(streamHandle, this, false, isSeqNumber, false))
          {
            if(!seqRcvyTable[i]->Recovery(seqNumber))
            {
              //Duplicate FRER packet detected !  ==> Drop
              m_frerDropTrace(packet);
              return false;
            }
            hardwareLatency += seqRcvyTable[i]->GetHardwareLatency();
            break;
          }
        }
        //Stream Transfert Function
        //Nothing to implement in the simulator
        //Sequence Generation if this function is enable for this stream handle
        //TODO
        //Stream splitting if this function is enable for this stream handle
        //TODO
        //Sequence encode => encode RTAG if this function is enable for this stream handle
        //TODO

        break;
    }
  }

  //Stream identification out-facing output (active)
  for (uint16_t i = 0; i < streamIdentityTable.size(); i++){
    if (streamIdentityTable[i]->Match(this, false, false, packet)){
      streamIdentityTable[i]->DoActiveUpdate(packet);
      hardwareLatency += streamIdentityTable[i]->GetHardwareLatency();
      break;
    }
  }



  //
  // If IsLinkUp() is false it means there is no channel to send any packet
  // over so we just hit the drop trace on the packet and return an error.
  //
  if (!IsLinkUp())
  {
      m_macTxDropTrace(packet);
      return false;
  }

  //Add timestamp if first emission
  TimestampTag tag(Simulator::Now());
  if (!packet->FindFirstMatchingByteTag(tag))
  {
          packet->AddByteTag(tag);
  }
  m_macTxTrace(packet);
  m_macTxAnimationTrace(packet, this);

  Ptr<Packet> pCopy = packet->Copy();
  EthernetHeader2 header;
  pCopy->RemoveHeader(header);
  uint8_t pcp = header.GetPcp();

  m_FIFOStateSnifferTrace(m_queues, m_txMachineState==BUSY, packet);
  // NS_LOG_INFO(Names::FindName(this) << " "<< Simulator::Now().GetNanoSeconds()<<" Enqueue pkt #"<<packet->GetUid() << " (Vid : " << header.GetVid() <<  ") in FIFO #" << unsigned(pcp));
  //
  // We should enqueue and dequeue the packet to hit the tracing hooks.
  //
  if (m_queues[pcp]->Enqueue(packet))
  {
    //Add the event after all the already present at this exact instant to avoid
    //the beginning of a transmission if a packet will be ready at the event just
    //after but at the same time instant.
    Simulator::Schedule(hardwareLatency, &TsnNetDevice::CheckForReadyPacket, this);
    //NS_LOG_INFO(Names::FindName(this) << " Enqueue pkt #"<<packet->GetUid() << " OK !");
    return true;
  }

  // Enqueue may fail (overflow)
  m_macTxDropTrace(packet);
  return false;
}


bool
TsnNetDevice::SendWithSpecificFIFO(Ptr<Packet> packet, const Address& dest, uint16_t ethertype, uint8_t pcp)
{
  NS_LOG_FUNCTION(this);
  return SendFrom(packet, GetAddress(), dest, ethertype, pcp);
}

bool
TsnNetDevice::SendFrom(Ptr<Packet> packet,
                                const Address& source,
                                const Address& dest,
                                uint16_t ethertype,
                                uint8_t pcp)
{
  // This function is use to put GPTP frame in a specific FIFO without using QTAG
  NS_LOG_FUNCTION(this);
  NS_ASSERT_MSG(m_queues.size() > pcp, "Not enough fifos ( 0 to "<< m_queues.size()-1 <<") to handle this pcp priority ("<< unsigned(pcp) <<") on Node " <<Names::FindName(GetNode()));

  AddHeader(packet, Mac48Address::ConvertFrom(dest), Mac48Address::ConvertFrom(source), ethertype);
  EthernetTrailer trailer;
  trailer.EnableFcs(true);
  trailer.CalcFcs(packet);
  packet->AddTrailer(trailer);


  //
  // If IsLinkUp() is false it means there is no channel to send any packet
  // over so we just hit the drop trace on the packet and return an error.
  //
  if (!IsLinkUp())
  {
      m_macTxDropTrace(packet);
      return false;
  }

  //Add timestamp if first emission
  TimestampTag tag(Simulator::Now());
  if (!packet->FindFirstMatchingByteTag(tag))
  {
          packet->AddByteTag(tag);
  }
  m_macTxTrace(packet);

  m_FIFOStateSnifferTrace(m_queues, m_txMachineState==BUSY, packet);
  // NS_LOG_INFO(Names::FindName(this) << " "<< Simulator::Now().GetNanoSeconds()<<" Enqueue pkt #"<<packet->GetUid() << " in FIFO #" << unsigned(pcp));
  //
  // We should enqueue and dequeue the packet to hit the tracing hooks.
  //
  if (m_queues[pcp]->Enqueue(packet))
  {
    //NS_LOG_INFO(Names::FindName(this) << " Enqueue pkt #"<<packet->GetUid() << " OK !");
    //Add the event after all the already present at this exact instant to avoid
    //the beginning of a transmission if a packet will be ready at the event just
    //after but at the same time instant.
    Simulator::Schedule(Time(0), &TsnNetDevice::CheckForReadyPacket, this);
    return true;
  }

  // Enqueue may fail (overflow)
  m_macTxDropTrace(packet);
  return false;
}




bool
TsnNetDevice::TransmitStart(Ptr<Packet> p, int queue_id)
{
    NS_LOG_FUNCTION(this << p);
    NS_LOG_LOGIC("UID is " << p->GetUid() << ")");

    //Timestamping at last bits emission
    NS_ASSERT_MSG(m_node != nullptr, "m_node was not set using void TsnNetDevice::SetNode(Ptr<TsnNode> node)");
    Time txTimestamp = m_node->GetTime();
    // NS_LOG_INFO("On " << Names::FindName(this)<< " Tx start at " << Simulator::Now().GetNanoSeconds() << " recording : " << txTimestamp.GetNanoSeconds());

    //Add a tag to compute delay between reception(or FIFO enter if first
    //emission port) and transmission start
    TimestampTag tag(Simulator::Now());
    p->AddByteTag(tag);

    //
    // This function is called to start the process of transmitting a packet.
    // We need to tell the channel that we've started wiggling the wire and
    // schedule an event that will be executed when the transmission is complete.
    //
    NS_ASSERT_MSG(m_txMachineState == READY, "Must be READY to transmit");
    m_txMachineState = BUSY;
    m_txHardwareLatencyExperienced = false;
    m_currentPkt = p;
    m_phyTxBeginTrace(m_currentPkt);

    Time preambleAndSFDGapTime = m_bps.CalculateBytesTxTime(m_preambleAndSFDGap);
    Time txTime = m_bps.CalculateBytesTxTime(p->GetSize());
    Time interpacketGapTime = m_bps.CalculateBytesTxTime(m_interframeGap);
    Time txCompleteTime = preambleAndSFDGapTime + txTime + interpacketGapTime;

    //NS_LOG_INFO(Names::FindName(this) << " "<< Simulator::Now().GetNanoSeconds()<<" Transmit pkt #"<<p->GetUid());

    Simulator::Schedule(txCompleteTime, &TsnTransmissionSelectionAlgo::TransmitComplete, m_transmissionSelectionAlgos[queue_id], p);
    m_transmissionSelectionAlgos[queue_id]->TransmitStart(p, txTime);

    NS_LOG_LOGIC("Schedule TransmitCompleteEvent in " << txCompleteTime.As(Time::S));
    Simulator::Schedule(txCompleteTime, &TsnNetDevice::TransmitComplete, this, queue_id);

    bool result = m_channel->TransmitStart(p, this, txCompleteTime-interpacketGapTime); //Pkt don't need to wait for the end of Interpacket gap to be considered as receive on the other end of the link
    if (!result)
    {
        m_phyTxDropTrace(p);
    }
    if(!m_rxCallbackWithTimestamp.IsNull()){
      m_txCallbackWithTimestamp(p, txTimestamp);
    }
    return result;
}


void
TsnNetDevice::TransmitComplete(int queue_id)
{
    NS_LOG_FUNCTION(this);
    // This function is called to when we're all done transmitting a packet.
    // We try and pull another packet off of the transmit queue.  If the queue
    // is empty, we are done, otherwise we need to start transmitting the
    // next packet.
    //
    NS_ASSERT_MSG(m_txMachineState == BUSY, "Must be BUSY if transmitting");
    m_txMachineState = READY;

    NS_ASSERT_MSG(m_currentPkt, "TsnNetDevice::TransmitComplete(): m_currentPkt zero");

    m_phyTxEndTrace(m_currentPkt);

    //m_transmissionSelectionAlgos[queue_id]->TransmitComplete(m_currentPkt);

    m_currentPkt = nullptr;

    //Add the event after all the already present at this exact instant to avoid
    //the beginning of a transmission if a packet will be ready at the event just
    //after but at the same time instant.
    Simulator::Schedule(Time(0), &TsnNetDevice::CheckForReadyPacket, this);
}

void
TsnNetDevice::CheckForReadyPacket()
{
  NS_LOG_FUNCTION(this);
  if (m_txMachineState != READY || m_txHardwareLatencyExperienced)
  {
    return;
  }

  int next_queue_id = TransmitSelection();
  if(next_queue_id==-1)
  {
    NS_LOG_LOGIC("No pending packets in device queue after tx complete");
    return;
  }

  //
  // Got another packet off of the queue, so start the transmit process again.
  //
  Ptr<Packet> p = m_queues[next_queue_id]->Dequeue();
  m_snifferTrace(p);
  m_promiscSnifferTrace(p);
  m_txHardwareLatencyExperienced = true;
  Time hardwareLatency = m_transmissionSelectionAlgos[next_queue_id]->GetHardwareLatency() + m_tas->GetHardwareLatency();
  Simulator::Schedule(hardwareLatency, &TsnNetDevice::TransmitStart, this, p, next_queue_id);
}



void
TsnNetDevice::Receive(Ptr<Packet> packet)
{
    NS_LOG_FUNCTION(this << packet);
    NS_LOG_LOGIC("UID is " << packet->GetUid());


    //Timestamping at last bits receiption thus compensate for the duration between first bit and last
    NS_ASSERT_MSG(m_node != nullptr, "m_node was not set using void TsnNetDevice::SetNode(Ptr<TsnNode> node)");
    Time rxTimestamp = m_node->GetTime() - (m_bps.CalculateBytesTxTime(m_preambleAndSFDGap) + m_bps.CalculateBytesTxTime(packet->GetSize()));

    Time hardwareLatency = Time(0);
    // NS_LOG_INFO("On " << Names::FindName(this)<< " Rx end at " << (Simulator::Now()- (m_bps.CalculateBytesTxTime(m_preambleAndSFDGap) + m_bps.CalculateBytesTxTime(packet->GetSize()))).GetNanoSeconds()  << " recording : " << rxTimestamp.GetNanoSeconds());

    if (m_receiveErrorModel && m_receiveErrorModel->IsCorrupt(packet))
    {
        //
        // If we have an error model and it indicates that it is time to lose a
        // corrupted packet, don't forward this packet up, let it go.
        //
        NS_LOG_LOGIC("Dropping pkt due to error model ");
        m_phyRxDropTrace(packet);
    }
    else
    {
        //Add timestamp to measure delay in the switches
        TimestampTag tag(Simulator::Now());
        packet->AddByteTag(tag);
        //
        // Hit the trace hooks.  All of these hooks are in the same place in this
        // device because it is so simple, but this is not usually the case in
        // more complicated devices.
        m_snifferTrace(packet);
        m_promiscSnifferTrace(packet);
        m_phyRxEndTrace(packet);

        //
        // Trace sinks will expect complete packets, not packets without some of the
        // headers.
        //
        Ptr<Packet> originalPacket = packet->Copy();

        //Check checksum
        EthernetTrailer trailer;
        packet->RemoveTrailer(trailer);
        if (Node::ChecksumEnabled())
        {
            trailer.EnableFcs(true);
        }

        bool crcGood = trailer.CheckFcs(packet);
        if (!crcGood)
        {
            NS_LOG_INFO("CRC error on Packet " << packet);
            m_phyRxDropTrace(packet);
            return;
        }

        //
        // Strip off the ethernet protocol header and forward this packet
        // up the protocol stack.  Since this is a simple point-to-point link,
        // there is no difference in what the promisc callback sees and what the
        // normal receive callback sees.
        //
        EthernetHeader2 header;
        packet->RemoveHeader(header);
        uint16_t protocol = header.GetEthertype();
        uint8_t priority = header.GetPcp();


        // Stream identification out-facing input
        std::vector<Ptr<StreamIdEntry>> streamIdentityTable = GetNode()->GetStreamIdentityTable();
        for (uint32_t i = 0; i < streamIdentityTable.size(); i++){
          if (streamIdentityTable[i]->Match(this, false, true, originalPacket)){
            uint32_t streamHandle = streamIdentityTable[i]->GetStreamHandle();
            hardwareLatency += streamIdentityTable[i]->GetHardwareLatency();

            //PSFP
            std::vector<Ptr<StreamFilterInstance>> streamFilterInstanceTable = GetNode()->GetStreamFilterInstanceTable();
            for (uint16_t i = 0; i < streamFilterInstanceTable.size(); i++){
              if (streamFilterInstanceTable[i]->Match(streamHandle, priority)){
                //MaxSDUSizeFilter
                if (streamFilterInstanceTable[i]->MaxSDUSizeFilter(originalPacket)){
                  m_maxSDUSizeFilterDropTrace(originalPacket);
                  return;
                }

                //TODO Stream Gate

                //Flow Meter
                std::vector<uint16_t> fmids =  streamFilterInstanceTable[i]->GetFlowMeterIds();
                std::vector<Ptr<FlowMeterInstance>> flowMeterInstanceTable = GetNode()->GetFlowMeterInstanceTable();
                bool pass = true;
                for (uint16_t j = 0; j < fmids.size(); j++){
                  if(flowMeterInstanceTable[fmids[j]]->Test(originalPacket)){
                    pass = false;
                  }
                }
                if (not pass){
                  streamFilterInstanceTable[i]->increaseRedFrameCount();
                  m_REDFrameDropTrace(originalPacket);
                  return;
                }

                break;
              }
            }

            //FRER
            // NS_LOG_INFO( "Stream handle of Pkt #"<<packet->GetUid() << " on input : " << streamHandle);
            bool isSeqNumber = false;
            uint16_t seqNumber = 0;
            //Sequence decode => extract RTAG if this function is enable for this stream handle
            //TODO

            //Individual Recovery if this function is enable for this stream handle
            //TODO

            //Sequence Recovery if this function is enable for this stream handle
            //TODO

            //Stream Transfert Function
            //Nothing to implement in the simulator

            //Sequence Generation if this function is enable for this stream handle
            std::vector<Ptr<SequenceGenerationFunction>> seqGenTable = GetNode()->GetSequenceGenerationTable();
            for (uint32_t i = 0; i < seqGenTable.size(); i++)
            {
              if(seqGenTable[i]->IsApplicable(streamHandle))
              {
                isSeqNumber = true;
                seqNumber =  seqGenTable[i]->GetSequenceNumber();
                break;
              }
            }

            //Stream splitting if this function is enable for this stream handle
            //TODO
            //Sequence encode => encode RTAG if this function is enable for this stream handle
            if (isSeqNumber)
            {
              std::vector<Ptr<SequenceEncodeDecodeFunction>> seqEncTable = GetNode()->GetSequenceEncodeDecodeTable();
              for (uint32_t i = 0; i < seqEncTable.size(); i++)
              {
                if(seqEncTable[i]->IsApplicable(streamHandle, this, false))
                {
                  seqEncTable[i]->Encode(originalPacket, seqNumber);
                  break;
                }
              }
            }

            break;
          }
        }


        //
        // Classify the packet based on its destination.
        //
        PacketType packetType;

        if (header.GetDest() == m_address)
        {
            packetType = PACKET_HOST;
        }
        else if (header.GetDest().IsBroadcast())
        {
            packetType = PACKET_BROADCAST;
        }
        else if (header.GetDest().IsGroup())
        {
            packetType = PACKET_MULTICAST;
        }
        else
        {
            packetType = PACKET_OTHERHOST;
        }

        if (!m_promiscCallback.IsNull())
        {
          Simulator::Schedule(hardwareLatency,
                              &TsnNetDevice::m_macPromiscRxTrace,
                              this,
                              originalPacket->Copy());
          Simulator::Schedule(hardwareLatency,
                              &TsnNetDevice::m_promiscCallback,
                              this,
                              this,
                              originalPacket,
                              protocol,
                              header.GetSrc(),
                              header.GetDest(),
                              packetType);

        }
        //
        // If this packet is not destined for some other host, it must be for us
        // as either a broadcast, multicast or unicast.  We need to hit the mac
        // packet received trace hook and forward the packet up the stack.
        //
        if (packetType != PACKET_OTHERHOST)
        {
            //NS_LOG_INFO((Simulator::Now()).As(Time::S) << " \t" << Names::FindName(m_node) << "/" << Names::FindName(this) <<" : Pkt #" << originalPacket->GetUid() <<" received by the netDevice ! " << originalPacket->ToString());
            m_macRxTrace(originalPacket);
            m_rxCallback(this, packet, protocol, header.GetSrc());
            if(!m_rxCallbackWithTimestamp.IsNull())
            {
              m_rxCallbackWithTimestamp(this, packet, protocol, header.GetSrc(), rxTimestamp);
            }
            m_latencyTrace(originalPacket);
        }
    }
}

Ptr<TsnNode>
TsnNetDevice::GetNode()
{
    return m_node;
}

void
TsnNetDevice::SetReceiveCallbackWithTimestamp(ReceiveCallbackWithTimestamp cb)
{
  m_rxCallbackWithTimestamp = cb;
}

void
TsnNetDevice::SetTransmitCallbackWithTimestamp(TransmitCallbackWithTimestamp cb)
{
  m_txCallbackWithTimestamp = cb;
}

void
TsnNetDevice::AddGclEntry(Time duration, uint8_t states)
{
  NS_LOG_FUNCTION(this);
  m_tas->AddGclEntry(duration, states);
}

void
TsnNetDevice::StartTas()
{
  NS_LOG_FUNCTION(this);
  StartTas(Time(0));
}

void
TsnNetDevice::StartTas(Time startTime)
{
  NS_LOG_FUNCTION(this);
  Simulator::Schedule(startTime, &Tas::Start, m_tas);
}

Ptr<Tas>
TsnNetDevice::GetTas()
{
  NS_LOG_FUNCTION(this);
  return m_tas;
}

}