--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/devices/wifi/minstrel-wifi-manager.h Thu Aug 13 08:45:47 2009 +0200
@@ -0,0 +1,255 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2009 Duy Nguyen
+ *
+ * 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: Duy Nguyen <duy@soe.ucsc.edu>
+ */
+
+
+
+#ifndef MINSTREL_WIFI_MANAGER_H
+#define MINSTREL_WIFI_MANAGER_H
+
+#include "wifi-remote-station-manager.h"
+#include "wifi-mode.h"
+#include "ns3/nstime.h"
+#include <vector>
+
+
+
+/**
+ * \author Duy Nguyen
+ * \brief Implementation of Minstrel Rate Control Algorithm
+ *
+ * Porting Minstrel from Madwifi and Linux Kernel
+ * http://linuxwireless.org/en/developers/Documentation/mac80211/RateControl/minstrel
+ */
+
+
+namespace ns3 {
+
+
+/**
+ * A struct to contain all information related to a data rate
+ */
+struct RateInfo{
+
+ /**
+ * Perfect transmission time calculation, or frame calculation
+ * Given a bit rate and a packet length n bytes
+ */
+ Time perfectTxTime;
+
+
+ uint32_t retryCount; ///< retry limit
+ uint32_t adjustedRetryCount; ///< adjust the retry limit for this rate
+ uint32_t numRateAttempt; ///< how many number of attempts so far
+ uint32_t numRateSuccess; ///< number of successful pkts
+ uint32_t prob; ///< (# pkts success )/(# total pkts)
+
+ /**
+ * EWMA calculation
+ * ewma_prob =[prob *(100 - ewma_level) + (ewma_prob_old * ewma_level)]/100
+ */
+ uint32_t ewmaProb;
+
+ uint32_t prevNumRateAttempt; ///< from last rate
+ uint32_t prevNumRateSuccess; ///< from last rate
+ uint64_t successHist; ///< aggregate of all successes
+ uint64_t attemptHist; ///< aggregate of all attempts
+ uint32_t throughput; ///< throughput of a rate
+};
+
+/**
+ * Data structure for a Minstrel Rate table
+ * A vector of a struct RateInfo
+ */
+typedef std::vector<struct RateInfo> MinstrelRate;
+
+/**
+ * Data structure for a Sample Rate table
+ * A vector of a vector uint32_t
+ */
+typedef std::vector<std::vector<uint32_t> > SampleRate;
+
+
+class MinstrelWifiManager : public WifiRemoteStationManager
+{
+
+public:
+ static TypeId GetTypeId (void);
+ MinstrelWifiManager ();
+ virtual ~MinstrelWifiManager();
+
+ virtual void SetupPhy (Ptr<WifiPhy> phy);
+
+ /// for estimating the TxTime of a packet with a given mode
+ Time GetCalcTxTime (WifiMode mode) const;
+ void AddCalcTxTime (WifiMode mode, Time t);
+
+private:
+ friend class MinstrelWifiRemoteStation;
+ virtual class WifiRemoteStation *CreateStation (void);
+
+ typedef std::vector<std::pair<Time,WifiMode> > TxTime;
+
+ TxTime m_calcTxTime; ///< to hold all the calculated TxTime for all modes
+ Time m_updateStats; ///< how frequent do we calculate the stats(1/10 seconds)
+ double m_lookAroundRate; ///< the % to try other rates than our current rate
+ double m_ewmaLevel; ///< exponential weighted moving average
+ uint32_t m_segmentSize; ///< largest allowable segment size
+ uint32_t m_sampleCol; ///< number of sample columns
+ uint32_t m_pktLen; ///< packet length used for calculate mode TxTime
+
+};
+
+class MinstrelWifiRemoteStation : public WifiRemoteStation
+{
+public:
+ MinstrelWifiRemoteStation (Ptr<MinstrelWifiManager> stations);
+
+ virtual ~MinstrelWifiRemoteStation ();
+
+protected:
+
+ /**
+ * when packet is successfully received
+ * see wifi-remote-station-manager.h for more documentation
+ */
+ virtual void DoReportRxOk (double rxSnr, WifiMode txMode);
+
+ /// when RTS timeout expires
+ virtual void DoReportRtsFailed (void);
+
+
+ /**
+ *
+ * Retry Chain table is implemented here
+ *
+ * Try | LOOKAROUND RATE | NORMAL RATE
+ * | random < best | random > best |
+ * --------------------------------------------------------------
+ * 1 | Best throughput | Random rate | Best throughput
+ * 2 | Random rate | Best throughput | Next best throughput
+ * 3 | Best probability | Best probability | Best probability
+ * 4 | Lowest Baserate | Lowest baserate | Lowest baserate
+ *
+ * Note: For clarity, multiple blocks of if's and else's are used
+ * After a failing 7 times, DoReportFinalDataFailed will be called
+ */
+ virtual void DoReportDataFailed (void);
+
+ /// when receive a CTS, associated with an RTS
+ virtual void DoReportRtsOk (double ctsSnr, WifiMode ctsMode, double rtsSnr);
+
+ /// when an ACK, associated with a data pkt, is received
+ virtual void DoReportDataOk (double ackSnr, WifiMode ackMode, double dataSnr);
+
+ /// after calling ReportRtsFailed if NeedRtsRetransmission returns false
+ virtual void DoReportFinalRtsFailed (void);
+
+ /// after calling ReportDataFailed if NeedDataRetransmission returns false
+ virtual void DoReportFinalDataFailed (void);
+
+
+private:
+ virtual Ptr<WifiRemoteStationManager> GetManager (void) const;
+
+ /**
+ * returns the transmission mode for sending this packet
+ * this function gets called when node is getting ready to send DATA
+ * see wifi-remote-station-manager.h for more documentation
+ */
+ virtual WifiMode DoGetDataMode (uint32_t size);
+
+ /// returns the transmission mode for sending RTS packet
+ virtual WifiMode DoGetRtsMode (void);
+
+ /// update the number of retries and reset accordingly
+ void UpdateRetry (void);
+
+ /// getting the next sample from Sample Table
+ uint32_t GetNextSample (void);
+
+ /// find a rate to use from Minstrel Table
+ uint32_t FindRate (void);
+
+ /// updating the Minstrel Table every 1/10 seconds
+ void UpdateStats (void);
+
+ /// initialize Minstrel Table
+ void RateInit (void);
+
+ /// initialize Sample Table
+ void InitSampleTable (void);
+
+ /// printing Sample Table
+ void PrintSampleTable (void);
+
+ /// printing Minstrel Table
+ void PrintTable (void);
+
+ /**
+ * \param packet lenghth
+ * \param current WifiMode
+ * \returns calcuated transmit duration
+ */
+ Time CalcRatePacket (uint32_t, WifiMode);
+
+ void CheckInit(void); ///< check for initializations
+
+ Ptr<MinstrelWifiManager> m_stations;
+
+ Time m_nextStatsUpdate; ///< 10 times every second
+
+ MinstrelRate m_minstrelTable; ///< minstrel table
+
+ SampleRate m_sampleTable; ///< sample table
+
+ /**
+ * To keep track of the current position in the our random sample table
+ * going row by row from 1st column until the 10th column(Minstrel defines 10)
+ * then we wrap back to the row 1 col 1.
+ * note: there are many other ways to do this.
+ */
+ uint32_t m_col, m_index;
+
+ uint32_t m_maxTpRate; ///< the current throughput rate
+ uint32_t m_maxTpRate2; ///< second highest throughput rate
+ uint32_t m_maxProbRate; ///< rate with highest prob of success
+
+ int m_packetCount; ///< total number of packets as of now
+ int m_sampleCount; ///< how many packets we have sample so far
+
+ bool m_isSampling; ///< a flag to indicate we are currently sampling
+ uint32_t m_sampleRate; ///< current sample rate
+ bool m_sampleRateSlower; ///< a flag to indicate sample rate is slower
+ uint32_t m_currentRate; ///< current rate we are using
+
+ uint32_t m_shortRetry; ///< short retries such as control packts
+ uint32_t m_longRetry; ///< long retries such as data packets
+ uint32_t m_retry; ///< total retries short + long
+ uint32_t m_err; ///< retry errors
+ uint32_t m_txrate; ///< current transmit rate
+
+ bool m_initialized; ///< for initializing tables
+
+
+};
+
+}// namespace ns3
+
+#endif /* MINSTREL_WIFI_MANAGER_H */