ReadOptions (tcpHeader, scoreboardUpdated);

  ReadOptions (tcpHeader, scoreboardUpdated);

  SequenceNumber32 ackNumber = tcpHeader.GetAckNumber ();

  SequenceNumber32 ackNumber = tcpHeader.GetAckNumber ();

  // RFC 6675 Section 5: 2nd, 3rd paragraph and point (A), (B) implementation

  // RFC 6675 Section 5: 2nd, 3rd paragraph and point (A), (B) implementation

  // are inside the function ProcessAck

  // are inside the function ProcessAck

  // If there is any data piggybacked, store it into m_rxBuffer

  // If there is any data piggybacked, store it into m_rxBuffer

  if (packet->GetSize () > 0)

  if (packet->GetSize () > 0)

}

}

void

void

{

{

  NS_LOG_FUNCTION (this << ackNumber << scoreboardUpdated);

  NS_LOG_FUNCTION (this << ackNumber << scoreboardUpdated);

  // RFC 6675, Section 5, 2nd paragraph:

  // RFC 6675, Section 5, 2nd paragraph:

  bool isDupack = m_sackEnabled ?

  bool isDupack = m_sackEnabled ?

        scoreboardUpdated

        scoreboardUpdated

        ackNumber < m_tcb->m_highTxMark;

        ackNumber < m_tcb->m_highTxMark;

  // RFC 6675, Section 5, 3rd paragraph:

  // RFC 6675, Section 5, 3rd paragraph:

  if (isDupack)

  if (isDupack)

    {

    {

      NS_LOG_DEBUG ("ACK of " << ackNumber <<

      NS_LOG_DEBUG ("ACK of " << ackNumber <<

                    " SND.NXT=" << m_tcb->m_nextTxSequence <<

                    " SND.NXT=" << m_tcb->m_nextTxSequence <<

                    " in state: " << TcpSocketState::TcpCongStateName[m_tcb->m_congState] <<

                    " in state: " << TcpSocketState::TcpCongStateName[m_tcb->m_congState] <<

                    " with m_recover: " << m_recover);

                    " with m_recover: " << m_recover);

      DupAck ();

      DupAck ();

    }

    }

      && ackNumber == m_tcb->m_highTxMark)

      && ackNumber == m_tcb->m_highTxMark)

    {

    {

      // Dupack, but the ACK is precisely equal to the nextTxSequence

      // Dupack, but the ACK is precisely equal to the nextTxSequence

      return;

      return;

    }

    }

           && ackNumber > m_tcb->m_highTxMark)

           && ackNumber > m_tcb->m_highTxMark)

    {

    {

      // ACK of the FIN bit ... nextTxSequence is not updated since we

      // ACK of the FIN bit ... nextTxSequence is not updated since we

      NS_LOG_DEBUG ("Update nextTxSequence manually to " << ackNumber);

      NS_LOG_DEBUG ("Update nextTxSequence manually to " << ackNumber);

      m_tcb->m_nextTxSequence = ackNumber;

      m_tcb->m_nextTxSequence = ackNumber;

    }

    }

    {

    {

      // DupAck. Artificially call PktsAcked: after all, one segment has been ACKed.

      // DupAck. Artificially call PktsAcked: after all, one segment has been ACKed.

      m_congestionControl->PktsAcked (m_tcb, 1, m_lastRtt);

      m_congestionControl->PktsAcked (m_tcb, 1, m_lastRtt);

    }

    }

    {

    {

      // Please remember that, with SACK, we can enter here even if we

      // Please remember that, with SACK, we can enter here even if we

      // received a dupack.

      // received a dupack.

      uint32_t segsAcked  = bytesAcked / m_tcb->m_segmentSize;

      uint32_t segsAcked  = bytesAcked / m_tcb->m_segmentSize;

      m_bytesAckedNotProcessed += bytesAcked % m_tcb->m_segmentSize;

      m_bytesAckedNotProcessed += bytesAcked % m_tcb->m_segmentSize;

      // the CA_RECOVERY phase. Just process this partial ack (RFC 5681)

      // the CA_RECOVERY phase. Just process this partial ack (RFC 5681)

      if (ackNumber < m_recover && m_tcb->m_congState == TcpSocketState::CA_RECOVERY)

      if (ackNumber < m_recover && m_tcb->m_congState == TcpSocketState::CA_RECOVERY)

        {

        {

          if (!m_sackEnabled)

          if (!m_sackEnabled)

            {

            {

              // Manually set the head as lost, it will be retransmitted.

              // Manually set the head as lost, it will be retransmitted.

  // Note the highest ACK and tell app to send more

  // Note the highest ACK and tell app to send more

  NS_LOG_LOGIC ("TCP " << this << " NewAck " << ack <<

  NS_LOG_LOGIC ("TCP " << this << " NewAck " << ack <<

                " numberAck " << (ack - m_txBuffer->HeadSequence ())); // Number bytes ack'ed

                " numberAck " << (ack - m_txBuffer->HeadSequence ())); // Number bytes ack'ed

  if (GetTxAvailable () > 0)

  if (GetTxAvailable () > 0)

    {

    {

      NotifySend (GetTxAvailable ());

      NotifySend (GetTxAvailable ());

   * \brief Process a received ack

   * \brief Process a received ack

   * \param ackNumber ack number

   * \param ackNumber ack number

   * \param scoreboardUpdated if true indicates that the scoreboard has been

   * \param scoreboardUpdated if true indicates that the scoreboard has been

   * updated with SACK information

   * updated with SACK information

   */

   */

  /**

  /**

   * \brief Recv of a data, put into buffer, call L7 to get it if necessary

   * \brief Recv of a data, put into buffer, call L7 to get it if necessary

                {

                {

                  // Partial ACK: Update the dupAck received count

                  // Partial ACK: Update the dupAck received count

                  m_dupAckRecv -= diff / GetSegSize (SENDER);

                  m_dupAckRecv -= diff / GetSegSize (SENDER);

                }

                }

            }

            }

          if (m_dupAckRecv == 3)

          if (m_dupAckRecv == 3)

            {

            {

              NS_LOG_DEBUG ("Loss of a segment detected");

              NS_LOG_DEBUG ("Loss of a segment detected");

            }

            }

          NS_LOG_DEBUG ("Dupack received, Update m_guessedBytesInFlight to " <<

          NS_LOG_DEBUG ("Dupack received, Update m_guessedBytesInFlight to " <<

                        m_guessedBytesInFlight);

                        m_guessedBytesInFlight);