/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2005 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: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
*/
#ifndef DCA_TXOP_H
#define DCA_TXOP_H
#include <stdint.h>
#include "ns3/callback.h"
#include "ns3/packet.h"
#include "ns3/nstime.h"
#include "ns3/object.h"
#include "wifi-mac-header.h"
#include "wifi-mode.h"
#include "wifi-remote-station-manager.h"
namespace ns3 {
class DcfState;
class DcfManager;
class WifiMacQueue;
class MacLow;
class WifiMacParameters;
class MacTxMiddle;
class RandomStream;
class MacStation;
class MacStations;
/**
* \brief handle packet fragmentation and retransmissions.
*
* This class implements the packet fragmentation and
* retransmission policy. It uses the ns3::MacLow and ns3::DcfManager
* helper classes to respectively send packets and decide when
* to send them. Packets are stored in a ns3::WifiMacQueue until
* they can be sent.
*
* The policy currently implemented uses a simple fragmentation
* threshold: any packet bigger than this threshold is fragmented
* in fragments whose size is smaller than the threshold.
*
* The retransmission policy is also very simple: every packet is
* retransmitted until it is either successfully transmitted or
* it has been retransmitted up until the ssrc or slrc thresholds.
*
* The rts/cts policy is similar to the fragmentation policy: when
* a packet is bigger than a threshold, the rts/cts protocol is used.
*/
class DcaTxop : public Object
{
public:
static TypeId GetTypeId (void);
typedef Callback <void, WifiMacHeader const&> TxOk;
typedef Callback <void, WifiMacHeader const&> TxFailed;
DcaTxop ();
~DcaTxop ();
void SetLow (Ptr<MacLow> low);
void SetManager (DcfManager *manager);
void SetWifiRemoteStationManager (Ptr<WifiRemoteStationManager> remoteManager);
/**
* \param callback the callback to invoke when a
* packet transmission was completed successfully.
*/
void SetTxOkCallback (TxOk callback);
/**
* \param callback the callback to invoke when a
* packet transmission was completed unsuccessfully.
*/
void SetTxFailedCallback (TxFailed callback);
void SetMaxQueueSize (uint32_t size);
void SetMaxQueueDelay (Time delay);
void SetMinCw (uint32_t minCw);
void SetMaxCw (uint32_t maxCw);
void SetAifsn (uint32_t aifsn);
uint32_t GetMinCw (void) const;
uint32_t GetMaxCw (void) const;
uint32_t GetAifsn (void) const;
/**
* \param packet packet to send
* \param hdr header of packet to send.
*
* Store the packet in the internal queue until it
* can be sent safely.
*/
void Queue (Ptr<const Packet> packet, WifiMacHeader const &hdr);
private:
class TransmissionListener;
class NavListener;
class PhyListener;
class Dcf;
friend class Dcf;
friend class TransmissionListener;
friend class WifiRemoteStation;
// Inherited from ns3::Object
Ptr<MacLow> Low (void);
/* dcf notifications forwarded here */
bool NeedsAccess (void) const;
void NotifyAccessGranted (void);
void NotifyInternalCollision (void);
void NotifyCollision (void);
/* event handlers */
void GotCts (double snr, WifiMode txMode);
void MissedCts (void);
void GotAck (double snr, WifiMode txMode);
void MissedAck (void);
void StartNext (void);
void Cancel (void);
void RestartAccessIfNeeded (void);
void StartAccessIfNeeded (void);
bool NeedRts (void);
bool NeedRtsRetransmission (void);
bool NeedDataRetransmission (void);
bool NeedFragmentation (void);
uint32_t GetNextFragmentSize (void);
uint32_t GetFragmentSize (void);
uint32_t GetFragmentOffset (void);
WifiRemoteStation *GetStation (Mac48Address to) const;
bool IsLastFragment (void);
void NextFragment (void);
Ptr<Packet> GetFragmentPacket (WifiMacHeader *hdr);
virtual void DoDispose (void);
Dcf *m_dcf;
DcfManager *m_manager;
TxOk m_txOkCallback;
TxFailed m_txFailedCallback;
Ptr<WifiMacQueue> m_queue;
MacTxMiddle *m_txMiddle;
Ptr <MacLow> m_low;
Ptr<WifiRemoteStationManager> m_stationManager;
TransmissionListener *m_transmissionListener;
RandomStream *m_rng;
bool m_accessOngoing;
Ptr<const Packet> m_currentPacket;
WifiMacHeader m_currentHdr;
uint8_t m_fragmentNumber;
};
} //namespace ns3
#endif /* DCA_TXOP_H */