/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

/*

 * Copyright (c) 2005,2006 INRIA

 *

 * 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: Federico Maguolo <maguolof@dei.unipd.it>

 */

#ifndef RRAA_WIFI_MANAGER_H

#define RRAA_WIFI_MANAGER_H

#include "ns3/nstime.h"

#include "wifi-remote-station-manager.h"

namespace ns3 {

struct RraaWifiRemoteStation;

/**

 * \brief Robust Rate Adaptation Algorithm

 * \ingroup wifi

 *

 * This is an implementation of RRAA as described in

 * "Robust rate adaptation for 802.11 wireless networks"

 * by "Starsky H. Y. Wong", "Hao Yang", "Songwu Lu", and,

 * "Vaduvur Bharghavan" published in Mobicom 06.

 */

class RraaWifiManager : public WifiRemoteStationManager

{

public:

  static TypeId GetTypeId (void);

  RraaWifiManager ();

  virtual ~RraaWifiManager ();

private:

  struct ThresholdsItem

  {

    uint32_t datarate;

    double pori;

    double pmtl;

    uint32_t ewnd;

  };

  //overriden from base class

  virtual WifiRemoteStation * DoCreateStation (void) const;

  virtual void DoReportRxOk (WifiRemoteStation *station,

                             double rxSnr, WifiMode txMode);

  virtual void DoReportRtsFailed (WifiRemoteStation *station);

  virtual void DoReportDataFailed (WifiRemoteStation *station);

  virtual void DoReportRtsOk (WifiRemoteStation *station,

                              double ctsSnr, WifiMode ctsMode, double rtsSnr);

  virtual void DoReportDataOk (WifiRemoteStation *station,

                               double ackSnr, WifiMode ackMode, double dataSnr);

  virtual void DoReportFinalRtsFailed (WifiRemoteStation *station);

  virtual void DoReportFinalDataFailed (WifiRemoteStation *station);

  virtual WifiTxVector DoGetDataTxVector (WifiRemoteStation *station, uint32_t size);

  virtual WifiTxVector DoGetRtsTxVector (WifiRemoteStation *station);

  virtual bool DoNeedRts (WifiRemoteStation *st,

                          Ptr<const Packet> packet, bool normally);

  virtual bool IsLowLatency (void) const;

  /**

   * Return the index for the maximum transmission rate for

   * the given station.

   *

   * \param station

   *

   * \return the index for the maximum transmission rate

   */

  uint32_t GetMaxRate (RraaWifiRemoteStation *station);

  /**

   * Return the index for the minimum transmission rate for

   * the given station.

   *

   * \param station

   *

   * \return the index for the minimum transmission rate

   */

  uint32_t GetMinRate (RraaWifiRemoteStation *station);

  /**

   * Check if the counter should be resetted.

   *

   * \param station

   */

  void CheckTimeout (RraaWifiRemoteStation *station);

  /**

   * Find an appropriate rate for the given station, using

   * a basic algorithm.

   *

   * \param station

   */

  void RunBasicAlgorithm (RraaWifiRemoteStation *station);

  /**

   * Activate the use of RTS for the given station if the conditions are met.

   *

   * \param station

   */

  void ARts (RraaWifiRemoteStation *station);

  /**

   * Reset the counters of the given station.

   *

   * \param station

   */

  void ResetCountersBasic (RraaWifiRemoteStation *station);

  /**

   * Get a threshold for the given mode.

   *

   * \param mode

   *

   * \return threshold

   */

  /**

   * Get a threshold for the given station and mode index.

   *

   * \param station

   * \param rate

   *

   * \return threshold

   */

  struct ThresholdsItem GetThresholds (RraaWifiRemoteStation *station, uint32_t rate) const;

  bool m_basic;

  Time m_timeout;

  uint32_t m_ewndfor54;

  uint32_t m_ewndfor48;

  uint32_t m_ewndfor36;

  uint32_t m_ewndfor24;

  uint32_t m_ewndfor18;

  uint32_t m_ewndfor12;

  uint32_t m_ewndfor9;

  uint32_t m_ewndfor6;

  double m_porifor48;

  double m_porifor36;

  double m_porifor24;

  double m_porifor18;

  double m_porifor12;

  double m_porifor9;

  double m_porifor6;

  double m_pmtlfor54;

  double m_pmtlfor48;

  double m_pmtlfor36;

  double m_pmtlfor24;

  double m_pmtlfor18;

  double m_pmtlfor12;

  double m_pmtlfor9;

};

} //namespace ns3

#endif /* RRAA_WIFI_MANAGER_H */