mac-low.h

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/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2005, 2006 INRIA
 * Copyright (c) 2009 MIRKO BANCHI
 *
 * 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
 *
 * Authors: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
 *          Mirko Banchi <mk.banchi@gmail.com>
 */

#ifndef MAC_LOW_H
#define MAC_LOW_H

#include <map>
#include "ns3/object.h"
#include "ns3/nstime.h"
#include "channel-access-manager.h"
#include "block-ack-cache.h"
#include "mac-low-transmission-parameters.h"
#include "qos-utils.h"
#include "wifi-mac-header.h"
#include "wifi-tx-vector.h"
#include "block-ack-type.h"
#include "wifi-mpdu-type.h"

class TwoLevelAggregationTest;
class AmpduAggregationTest;

namespace ns3 {

class WifiPhy;
class Txop;
class QosTxop;
class WifiMacQueueItem;
class WifiMacQueue;
class BlockAckAgreement;
class MgtAddBaResponseHeader;
class WifiRemoteStationManager;
class CtrlBAckRequestHeader;
class CtrlBAckResponseHeader;

class MacLow : public Object
{
public:
  friend class ::TwoLevelAggregationTest;
  friend class ::AmpduAggregationTest;
  typedef Callback<void, Ptr<Packet>, const WifiMacHeader*> MacLowRxCallback;

  MacLow ();
  virtual ~MacLow ();

  static TypeId GetTypeId (void);

  void SetPhy (const Ptr<WifiPhy> phy);
  Ptr<WifiPhy> GetPhy (void) const;
  void ResetPhy (void);
  void SetWifiRemoteStationManager (const Ptr<WifiRemoteStationManager> manager);
  void SetAddress (Mac48Address ad);
  void SetAckTimeout (Time ackTimeout);
  void SetBasicBlockAckTimeout (Time blockAckTimeout);
  void SetCompressedBlockAckTimeout (Time blockAckTimeout);
  void SetCtsToSelfSupported (bool enable);
  void SetCtsTimeout (Time ctsTimeout);
  void SetSifs (Time sifs);
  void SetRifs (Time rifs);
  void SetSlotTime (Time slotTime);
  void SetPifs (Time pifs);
  void SetBeaconInterval (Time interval);
  void SetCfpMaxDuration (Time duration);
  void SetBssid (Mac48Address ad);
  void SetPromisc (void);
  bool GetCtsToSelfSupported () const;
  Mac48Address GetAddress (void) const;
  Time GetAckTimeout (void) const;
  Time GetBasicBlockAckTimeout () const;
  Time GetCompressedBlockAckTimeout () const;
  Time GetCtsTimeout (void) const;
  Time GetSifs (void) const;
  Time GetSlotTime (void) const;
  Time GetPifs (void) const;
  Time GetRifs (void) const;
  Time GetBeaconInterval (void) const;
  Time GetCfpMaxDuration (void) const;
  Time GetRemainingCfpDuration (void) const;
  Mac48Address GetBssid (void) const;
  bool IsPromisc (void) const;

  void SetRxCallback (Callback<void,Ptr<Packet>,const WifiMacHeader *> callback);
  void RegisterDcf (Ptr<ChannelAccessManager> dcf);

  Time CalculateTransmissionTime (Ptr<const Packet> packet,
                                  const WifiMacHeader* hdr,
                                  const MacLowTransmissionParameters& parameters) const;

  Time CalculateOverallTxTime (Ptr<const Packet> packet,
                               const WifiMacHeader* hdr,
                               const MacLowTransmissionParameters& params,
                               uint32_t fragmentSize = 0) const;

  virtual void StartTransmission (Ptr<const Packet> packet,
                                  const WifiMacHeader* hdr,
                                  MacLowTransmissionParameters parameters,
                                  Ptr<Txop> txop);

  void ReceiveOk (Ptr<Packet> packet, double rxSnr, WifiTxVector txVector, bool ampduSubframe);
  void ReceiveError (Ptr<Packet> packet, double rxSnr);
  void NotifySwitchingStartNow (Time duration);
  void NotifySleepNow (void);
  void NotifyOffNow (void);
  void CreateBlockAckAgreement (const MgtAddBaResponseHeader *respHdr,
                                Mac48Address originator,
                                uint16_t startingSeq);
  void DestroyBlockAckAgreement (Mac48Address originator, uint8_t tid);
  void RegisterEdcaForAc (AcIndex ac, Ptr<QosTxop> edca);
  Ptr<Packet> AggregateToAmpdu (Ptr<const Packet> packet, const WifiMacHeader hdr);
  void DeaggregateAmpduAndReceive (Ptr<Packet> aggregatedPacket, double rxSnr, WifiTxVector txVector);
  bool StopMpduAggregation (Ptr<const Packet> peekedPacket, WifiMacHeader peekedHdr, Ptr<Packet> aggregatedPacket, uint8_t blockAckSize) const;
  void FlushAggregateQueue (uint8_t tid);

  virtual WifiTxVector GetDataTxVector (Ptr<const Packet> packet, const WifiMacHeader *hdr) const;
  bool DoNavStartNow (Time duration);
  virtual bool IsCfPeriod (void) const;
  bool CanTransmitNextCfFrame (void) const;


private:
  void CancelAllEvents (void);
  uint32_t GetCfEndSize (void) const;
  void ForwardDown (Ptr<const Packet> packet, const WifiMacHeader *hdr, WifiTxVector txVector);
  void SendMpdu (Ptr<const Packet> packet, WifiTxVector txVector, MpduType mpdutype);
  WifiTxVector GetRtsTxVector (Ptr<const Packet> packet, const WifiMacHeader *hdr) const;
  WifiTxVector GetCtsTxVector (Mac48Address to, WifiMode rtsTxMode) const;
  WifiTxVector GetAckTxVector (Mac48Address to, WifiMode dataTxMode) const;
  WifiTxVector GetBlockAckTxVector (Mac48Address to, WifiMode dataTxMode) const;
  WifiTxVector GetCtsTxVectorForRts (Mac48Address to, WifiMode rtsTxMode) const;
  WifiTxVector GetAckTxVectorForData (Mac48Address to, WifiMode dataTxMode) const;
  Time GetCtsDuration (WifiTxVector ctsTxVector) const;
  Time GetCtsDuration (Mac48Address to, WifiTxVector rtsTxVector) const;
  Time GetAckDuration (WifiTxVector ackTxVector) const;
  Time GetAckDuration (Mac48Address to, WifiTxVector dataTxVector) const;
  Time GetBlockAckDuration (WifiTxVector blockAckReqTxVector, BlockAckType type) const;
  bool NeedRts (void) const;
  bool NeedCtsToSelf (void) const;

  void NotifyNav (Ptr<const Packet> packet,const WifiMacHeader &hdr);
  void DoNavResetNow (Time duration);
  bool IsNavZero (void) const;
  void NotifyAckTimeoutStartNow (Time duration);
  void NotifyAckTimeoutResetNow ();
  void NotifyCtsTimeoutStartNow (Time duration);
  void NotifyCtsTimeoutResetNow ();
  void NavCounterResetCtsMissed (Time rtsEndRxTime);
  /* Event handlers */
  void NormalAckTimeout (void);
  void BlockAckTimeout (void);
  void CtsTimeout (void);
  void CfPollTimeout (void);
  void SendCtsToSelf (void);
  void SendCtsAfterRts (Mac48Address source, Time duration, WifiTxVector rtsTxVector, double rtsSnr);
  void SendAckAfterData (Mac48Address source, Time duration, WifiMode dataTxMode, double dataSnr);
  void SendDataAfterCts (Time duration);

  void WaitIfsAfterEndTxFragment (void);
  void WaitIfsAfterEndTxPacket (void);

  void EndTxNoAck (void);
  void SendRtsForPacket (void);
  void SendDataPacket (void);
  void StartDataTxTimers (WifiTxVector dataTxVector);

  void DoDispose (void);

  void RxCompleteBufferedPacketsWithSmallerSequence (uint16_t seq, Mac48Address originator, uint8_t tid);
  void RxCompleteBufferedPacketsUntilFirstLost (Mac48Address originator, uint8_t tid);
  bool ReceiveMpdu (Ptr<Packet> packet, WifiMacHeader hdr);
  bool StoreMpduIfNeeded (Ptr<Packet> packet, WifiMacHeader hdr);
  void SendBlockAckAfterBlockAckRequest (const CtrlBAckRequestHeader reqHdr, Mac48Address originator,
                                         Time duration, WifiMode blockAckReqTxMode, double rxSnr);
  void SendBlockAckAfterAmpdu (uint8_t tid, Mac48Address originator,
                               Time duration, WifiTxVector blockAckReqTxVector, double rxSnr);
  void SendBlockAckResponse (const CtrlBAckResponseHeader* blockAck, Mac48Address originator, bool immediate,
                             Time duration, WifiMode blockAckReqTxMode, double rxSnr);
  void ResetBlockAckInactivityTimerIfNeeded (BlockAckAgreement &agreement);

  void SetupPhyMacLowListener (const Ptr<WifiPhy> phy);
  void RemovePhyMacLowListener (Ptr<WifiPhy> phy);
  bool IsAmpdu (Ptr<const Packet> packet, const WifiMacHeader hdr);
  void InsertInTxQueue (Ptr<const Packet> packet, const WifiMacHeader &hdr, Time tStamp, uint8_t tid);
  Ptr<Packet> PerformMsduAggregation (Ptr<const Packet> packet, WifiMacHeader *hdr, Time *tstamp, Ptr<Packet> currentAmpduPacket, uint8_t blockAckSize);

  Ptr<WifiPhy> m_phy; 
  Ptr<WifiRemoteStationManager> m_stationManager; 
  MacLowRxCallback m_rxCallback; 

  struct Item
  {
    Ptr<const Packet> packet; 
    WifiMacHeader hdr; 
    Time timestamp; 
  }; 

  struct CfAckInfo
  {
    bool appendCfAck; 
    bool expectCfAck; 
    Mac48Address address; 
  };

  typedef std::vector<Ptr<ChannelAccessManager> >::const_iterator ChannelAccessManagersCI;
  typedef std::vector<Ptr<ChannelAccessManager> > ChannelAccessManagers;
  ChannelAccessManagers m_channelAccessManagers; 

  EventId m_normalAckTimeoutEvent;      
  EventId m_blockAckTimeoutEvent;       
  EventId m_ctsTimeoutEvent;            
  EventId m_sendCtsEvent;               
  EventId m_sendAckEvent;               
  EventId m_sendDataEvent;              
  EventId m_waitIfsEvent;               
  EventId m_endTxNoAckEvent;            
  EventId m_navCounterResetCtsMissed;   

  Ptr<Packet> m_currentPacket;              
  WifiMacHeader m_currentHdr;               
  Ptr<Txop> m_currentTxop;                  
  MacLowTransmissionParameters m_txParams;  
  Mac48Address m_self;                      
  Mac48Address m_bssid;                     
  Time m_ackTimeout;                        
  Time m_basicBlockAckTimeout;              
  Time m_compressedBlockAckTimeout;         
  Time m_ctsTimeout;                        
  Time m_sifs;                              
  Time m_slotTime;                          
  Time m_pifs;                              
  Time m_rifs;                              

  Time m_beaconInterval;   
  Time m_cfpMaxDuration;   

  Time m_lastNavStart;     
  Time m_lastNavDuration;  

  Time m_cfpStart;          
  Time m_lastBeacon;        
  Time m_cfpForeshortening; 

  bool m_promisc;  
  bool m_ampdu;    

  class PhyMacLowListener * m_phyMacLowListener; 

  /*
   * BlockAck data structures.
   */
  typedef std::pair<Ptr<Packet>, WifiMacHeader> BufferedPacket; 
  typedef std::list<BufferedPacket>::iterator BufferedPacketI; 

  typedef std::pair<Mac48Address, uint8_t> AgreementKey; 
  typedef std::pair<BlockAckAgreement, std::list<BufferedPacket> > AgreementValue; 

  typedef std::map<AgreementKey, AgreementValue> Agreements; 
  typedef std::map<AgreementKey, AgreementValue>::iterator AgreementsI; 

  typedef std::map<AgreementKey, BlockAckCache> BlockAckCaches; 
  typedef std::map<AgreementKey, BlockAckCache>::iterator BlockAckCachesI; 

  Agreements m_bAckAgreements; 
  BlockAckCaches m_bAckCaches; 

  typedef std::map<AcIndex, Ptr<QosTxop> > QueueEdcas; 
  QueueEdcas m_edca; 

  bool m_ctsToSelfSupported;             
  Ptr<WifiMacQueue> m_aggregateQueue[8]; 
  std::vector<Item> m_txPackets[8];      
  WifiTxVector m_currentTxVector;        

  CfAckInfo m_cfAckInfo; 
};

} //namespace ns3

#endif /* MAC_LOW_H */