Implementation of Minstrel Rate Control AlgorithmPorting Minstrel from Madwifi and Linux Kernel http://linuxwireless.org/en/developers/Documentation/mac80211/RateControl/minstrel. More...

#include <minstrel-wifi-manager.h>

Inheritance diagram for ns3::MinstrelWifiManager:

Public Member Functions
int64_t	AssignStreams (int64_t stream)

virtual void	SetupPhy (Ptr< WifiPhy > phy)

Public Member Functions inherited from ns3::WifiRemoteStationManager
void	AddBasicMode (WifiMode mode)

void	AddSupportedMode (Mac48Address address, WifiMode mode)

WifiMode	GetAckMode (Mac48Address address, WifiMode dataMode)

WifiMode	GetBasicMode (uint32_t i) const

WifiMode	GetCtsMode (Mac48Address address, WifiMode rtsMode)

WifiMode	GetDataMode (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet, uint32_t fullPacketSize)

WifiMode	GetDefaultMode (void) const

uint32_t	GetFragmentationThreshold (void) const

uint32_t	GetFragmentOffset (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet, uint32_t fragmentNumber)

uint32_t	GetFragmentSize (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet, uint32_t fragmentNumber)

WifiRemoteStationInfo	GetInfo (Mac48Address address)

uint32_t	GetMaxSlrc (void) const

uint32_t	GetMaxSsrc (void) const

uint32_t	GetNBasicModes (void) const

WifiMode	GetNonUnicastMode (void) const

uint32_t	GetRtsCtsThreshold (void) const

WifiMode	GetRtsMode (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet)

bool	IsAssociated (Mac48Address address) const

bool	IsBrandNew (Mac48Address address) const

bool	IsLastFragment (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet, uint32_t fragmentNumber)

bool	IsWaitAssocTxOk (Mac48Address address) const

bool	NeedDataRetransmission (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet)

bool	NeedFragmentation (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet)

bool	NeedRts (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet)

bool	NeedRtsRetransmission (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet)

void	PrepareForQueue (Mac48Address address, const WifiMacHeader *header, Ptr< const Packet > packet, uint32_t fullPacketSize)

void	RecordDisassociated (Mac48Address address)

void	RecordGotAssocTxFailed (Mac48Address address)

void	RecordGotAssocTxOk (Mac48Address address)

void	RecordWaitAssocTxOk (Mac48Address address)

void	ReportDataFailed (Mac48Address address, const WifiMacHeader *header)

void	ReportDataOk (Mac48Address address, const WifiMacHeader *header, double ackSnr, WifiMode ackMode, double dataSnr)

void	ReportFinalDataFailed (Mac48Address address, const WifiMacHeader *header)

void	ReportFinalRtsFailed (Mac48Address address, const WifiMacHeader *header)

void	ReportRtsFailed (Mac48Address address, const WifiMacHeader *header)

void	ReportRtsOk (Mac48Address address, const WifiMacHeader *header, double ctsSnr, WifiMode ctsMode, double rtsSnr)

void	ReportRxOk (Mac48Address address, const WifiMacHeader *header, double rxSnr, WifiMode txMode)

void	Reset (void)

void	Reset (Mac48Address address)

void	SetFragmentationThreshold (uint32_t threshold)

void	SetMaxSlrc (uint32_t maxSlrc)

void	SetMaxSsrc (uint32_t maxSsrc)

void	SetRtsCtsThreshold (uint32_t threshold)

Public Member Functions inherited from ns3::Object
void	AggregateObject (Ptr< Object > other)

void	Dispose (void)

AggregateIterator	GetAggregateIterator (void) const

virtual TypeId	GetInstanceTypeId (void) const

template<typename T >
Ptr< T >	GetObject (void) const

template<typename T >
Ptr< T >	GetObject (TypeId tid) const

void	Initialize (void)

Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
	SimpleRefCount (const SimpleRefCount &o)

uint32_t	GetReferenceCount (void) const

SimpleRefCount &	operator= (const SimpleRefCount &o)

void	Ref (void) const

void	Unref (void) const

Public Member Functions inherited from ns3::ObjectBase
void	GetAttribute (std::string name, AttributeValue &value) const

bool	GetAttributeFailSafe (std::string name, AttributeValue &attribute) const

void	SetAttribute (std::string name, const AttributeValue &value)

bool	SetAttributeFailSafe (std::string name, const AttributeValue &value)

bool	TraceConnect (std::string name, std::string context, const CallbackBase &cb)

bool	TraceConnectWithoutContext (std::string name, const CallbackBase &cb)

bool	TraceDisconnect (std::string name, std::string context, const CallbackBase &cb)

bool	TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb)

Static Public Member Functions
static TypeId	GetTypeId (void)

Static Public Member Functions inherited from ns3::WifiRemoteStationManager
static TypeId	GetTypeId (void)

Static Public Member Functions inherited from ns3::Object
static TypeId	GetTypeId (void)

Static Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
static void	Cleanup (void)

Static Public Member Functions inherited from ns3::ObjectBase
static TypeId	GetTypeId (void)

Private Types
typedef std::vector< std::pair < Time, WifiMode > >	TxTime

Private Member Functions
void	AddCalcTxTime (WifiMode mode, Time t)

void	CheckInit (MinstrelWifiRemoteStation *station)
	check for initializations

virtual WifiRemoteStation *	DoCreateStation (void) const

virtual WifiMode	DoGetDataMode (WifiRemoteStation *station, uint32_t size)

virtual WifiMode	DoGetRtsMode (WifiRemoteStation *station)

virtual void	DoReportDataFailed (WifiRemoteStation *station)

virtual void	DoReportDataOk (WifiRemoteStation *station, double ackSnr, WifiMode ackMode, double dataSnr)

virtual void	DoReportFinalDataFailed (WifiRemoteStation *station)

virtual void	DoReportFinalRtsFailed (WifiRemoteStation *station)

virtual void	DoReportRtsFailed (WifiRemoteStation *station)

virtual void	DoReportRtsOk (WifiRemoteStation *station, double ctsSnr, WifiMode ctsMode, double rtsSnr)

virtual void	DoReportRxOk (WifiRemoteStation *station, double rxSnr, WifiMode txMode)

uint32_t	FindRate (MinstrelWifiRemoteStation *station)
	find a rate to use from Minstrel Table More...

Time	GetCalcTxTime (WifiMode mode) const
	for estimating the TxTime of a packet with a given mode

uint32_t	GetNextSample (MinstrelWifiRemoteStation *station)
	getting the next sample from Sample Table More...

void	InitSampleTable (MinstrelWifiRemoteStation *station)
	initialize Sample Table More...

virtual bool	IsLowLatency (void) const

void	PrintSampleTable (MinstrelWifiRemoteStation *station)
	printing Sample Table

void	PrintTable (MinstrelWifiRemoteStation *station)
	printing Minstrel Table

void	RateInit (MinstrelWifiRemoteStation *station)
	initialize Minstrel Table

void	UpdateRetry (MinstrelWifiRemoteStation *station)
	update the number of retries and reset accordingly

void	UpdateStats (MinstrelWifiRemoteStation *station)
	updating the Minstrel Table every 1/10 seconds More...

Private Attributes
TxTime	m_calcTxTime
	to hold all the calculated TxTime for all modes

double	m_ewmaLevel
	exponential weighted moving average

double	m_lookAroundRate
	the % to try other rates than our current rate

MinstrelRate	m_minstrelTable
	minstrel table

uint32_t	m_nsupported
	modes supported

uint32_t	m_pktLen
	packet length used for calculate mode TxTime

uint32_t	m_sampleCol
	number of sample columns

SampleRate	m_sampleTable
	sample table

uint32_t	m_segmentSize
	largest allowable segment size

Ptr< UniformRandomVariable >	m_uniformRandomVariable
	Provides uniform random variables.

Time	m_updateStats
	how frequent do we calculate the stats(1/10 seconds)

Additional Inherited Members
Protected Member Functions inherited from ns3::WifiRemoteStationManager
virtual void	DoDispose (void)

uint32_t	GetNSupported (const WifiRemoteStation *station) const

WifiMode	GetSupported (const WifiRemoteStation *station, uint32_t i) const

Protected Member Functions inherited from ns3::Object
	Object (const Object &o)

virtual void	DoInitialize (void)

virtual void	NotifyNewAggregate (void)

Protected Member Functions inherited from ns3::ObjectBase
void	ConstructSelf (const AttributeConstructionList &attributes)

virtual void	NotifyConstructionCompleted (void)

Detailed Description

Implementation of Minstrel Rate Control Algorithm

Porting Minstrel from Madwifi and Linux Kernel http://linuxwireless.org/en/developers/Documentation/mac80211/RateControl/minstrel.

Author: Duy Nguyen

Config Paths

ns3::MinstrelWifiManager is accessible through the following paths with Config::Set and Config::Connect:

/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/RemoteStationManager/$ns3::MinstrelWifiManager

Attributes

UpdateStatistics: The interval between updating statistics table
- Set with class: TimeValue
- Underlying type: Time
- Initial value: +100000000.0ns
- Flags: construct write read
LookAroundRate: the percentage to try other rates
- Set with class: ns3::DoubleValue
- Underlying type: double -1.79769e+308:1.79769e+308
- Initial value: 10
- Flags: construct write read
EWMA: EWMA level
- Set with class: ns3::DoubleValue
- Underlying type: double -1.79769e+308:1.79769e+308
- Initial value: 75
- Flags: construct write read
SegmentSize: The largest allowable segment size packet
- Set with class: ns3::DoubleValue
- Underlying type: double -1.79769e+308:1.79769e+308
- Initial value: 6000
- Flags: construct write read
SampleColumn: The number of columns used for sampling
- Set with class: ns3::DoubleValue
- Underlying type: double -1.79769e+308:1.79769e+308
- Initial value: 10
- Flags: construct write read
PacketLength: The packet length used for calculating mode TxTime
- Set with class: ns3::DoubleValue
- Underlying type: double -1.79769e+308:1.79769e+308
- Initial value: 1200
- Flags: construct write read

Attributes defined in parent class ns3::WifiRemoteStationManager

IsLowLatency: If true, we attempt to modelize a so-called low-latency device: a device where decisions about tx parameters can be made on a per-packet basis and feedback about the transmission of each packet is obtained before sending the next. Otherwise, we modelize a high-latency device, that is a device where we cannot update our decision about tx parameters after every packet transmission.
- Set with class: BooleanValue
- Underlying type: bool
- Flags: read
MaxSsrc: The maximum number of retransmission attempts for an RTS. This value will not have any effect on some rate control algorithms.
- Set with class: ns3::UintegerValue
- Underlying type: uint32_t 0:4294967295
- Initial value: 7
- Flags: construct write read
MaxSlrc: The maximum number of retransmission attempts for a DATA packet. This value will not have any effect on some rate control algorithms.
- Set with class: ns3::UintegerValue
- Underlying type: uint32_t 0:4294967295
- Initial value: 7
- Flags: construct write read
RtsCtsThreshold: If the size of the data packet + LLC header + MAC header + FCS trailer is bigger than this value, we use an RTS/CTS handshake before sending the data, as per IEEE Std. 802.11-2007, Section 9.2.6. This value will not have any effect on some rate control algorithms.
- Set with class: ns3::UintegerValue
- Underlying type: uint32_t 0:4294967295
- Initial value: 2346
- Flags: construct write read
FragmentationThreshold: If the size of the data packet + LLC header + MAC header + FCS trailer is biggerthan this value, we fragment it such that the size of the fragments are equal or smaller than this value, as per IEEE Std. 802.11-2007, Section 9.4. This value will not have any effect on some rate control algorithms.
- Set with class: ns3::UintegerValue
- Underlying type: uint32_t 0:4294967295
- Initial value: 2346
- Flags: construct write read
NonUnicastMode: Wifi mode used for non-unicast transmissions.
- Set with class: WifiModeValue
- Underlying type: WifiMode
- Initial value: Invalid-WifiMode
- Flags: construct write read

No TraceSources are defined for this type.

TraceSources defined in parent class ns3::WifiRemoteStationManager

MacTxRtsFailed: The transmission of a RTS by the MAC layer has failed
MacTxDataFailed: The transmission of a data packet by the MAC layer has failed
MacTxFinalRtsFailed: The transmission of a RTS has exceeded the maximum number of attempts
MacTxFinalDataFailed: The transmission of a data packet has exceeded the maximum number of attempts

Definition at line 87 of file minstrel-wifi-manager.h.

Member Function Documentation

int64_t ns3::MinstrelWifiManager::AssignStreams ( int64_t stream )

Assign a fixed random variable stream number to the random variables used by this model. Return the number of streams (possibly zero) that have been assigned.

Parameters

stream first stream index to use

Returns: the number of stream indices assigned by this model

Definition at line 145 of file minstrel-wifi-manager.cc.

References m_uniformRandomVariable, NS_LOG_FUNCTION, and ns3::RandomVariableStream::SetStream().

WifiRemoteStation * ns3::MinstrelWifiManager::DoCreateStation ( void ) const

privatevirtual

Returns: a new station data structure

Implements ns3::WifiRemoteStationManager.

Definition at line 174 of file minstrel-wifi-manager.cc.

WifiMode ns3::MinstrelWifiManager::DoGetDataMode	(	WifiRemoteStation *	station,
		uint32_t	size
	)

privatevirtual

Parameters

station	the station with which we need to communicate
size	size of the packet or fragment we want to send

Returns: the transmission mode to use to send a packet to the station

Note: This method is called before sending a unicast packet or a fragment of a unicast packet to decide which transmission mode to use.

start the rate at half way

Implements ns3::WifiRemoteStationManager.

Definition at line 439 of file minstrel-wifi-manager.cc.

References CheckInit(), ns3::MinstrelWifiRemoteStation::m_initialized, m_nsupported, ns3::MinstrelWifiRemoteStation::m_txrate, and UpdateStats().

WifiMode ns3::MinstrelWifiManager::DoGetRtsMode ( WifiRemoteStation * station )

privatevirtual

Parameters

station the station with which we need to communicate

Returns: the transmission mode to use to send an rts to the station

Note: This method is called before sending an rts to a station to decide which transmission mode to use for the rts.

Implements ns3::WifiRemoteStationManager.

Definition at line 455 of file minstrel-wifi-manager.cc.

References ns3::MinstrelWifiRemoteStation::m_txrate, and NS_LOG_DEBUG.

void ns3::MinstrelWifiManager::DoReportDataFailed ( WifiRemoteStation * station )

privatevirtual

Retry Chain table is implemented here

Try | LOOKAROUND RATE | NORMAL RATE

| random < best | random > best |

Note: For clarity, multiple blocks of if's and else's are used After a failing 7 times, DoReportFinalDataFailed will be called

for normal rate, we're not currently sampling random rates

use best throughput rate

< there's still a few retries left

use second best throughput rate

use best probability rate

use lowest base rate

for look-around rate, we're currently sampling random rates

current sampling rate is slower than the current best rate

use best throughput rate

< there are a few retries left

use random rate

use max probability rate

use lowest base rate

current sampling rate is better than current best rate

use random rate

< keep using it

use the best rate

use the best probability rate

use the lowest base rate

Implements ns3::WifiRemoteStationManager.

Definition at line 248 of file minstrel-wifi-manager.cc.

References CheckInit(), ns3::MinstrelWifiRemoteStation::m_initialized, ns3::MinstrelWifiRemoteStation::m_isSampling, ns3::MinstrelWifiRemoteStation::m_longRetry, ns3::MinstrelWifiRemoteStation::m_maxProbRate, ns3::MinstrelWifiRemoteStation::m_maxTpRate, ns3::MinstrelWifiRemoteStation::m_maxTpRate2, m_minstrelTable, ns3::MinstrelWifiRemoteStation::m_sampleRate, ns3::MinstrelWifiRemoteStation::m_sampleRateSlower, ns3::MinstrelWifiRemoteStation::m_txrate, and NS_LOG_DEBUG.

uint32_t ns3::MinstrelWifiManager::FindRate ( MinstrelWifiRemoteStation * station )

private

find a rate to use from Minstrel Table

for determining when to try a sample rate

if we are below the target of look around rate percentage, look around note: do it randomly by flipping a coin instead sampling all at once until it reaches the look around rate

now go through the table and find an index rate

This if condition is used to make sure that we don't need to use the sample rate it is the same as our current rate

start sample count

set flag that we are currently sampling

bookeeping for resetting stuff

error check

set the rate that we're currently sampling

is this rate slower than the current best rate

using the best rate instead

continue using the best rate

Definition at line 489 of file minstrel-wifi-manager.cc.

uint32_t ns3::MinstrelWifiManager::GetNextSample ( MinstrelWifiRemoteStation * station )

private

getting the next sample from Sample Table

bookeeping for m_index and m_col variables

Definition at line 469 of file minstrel-wifi-manager.cc.

References ns3::MinstrelWifiRemoteStation::m_col, m_nsupported, m_sampleCol, and m_sampleTable.

Referenced by FindRate().

void ns3::MinstrelWifiManager::InitSampleTable ( MinstrelWifiRemoteStation * station )

private

initialize Sample Table

for off-seting to make rates fall between 0 and numrates

The next two lines basically tries to generate a random number between 0 and the number of available rates

this loop is used for filling in other uninitilized places

Definition at line 739 of file minstrel-wifi-manager.cc.

References ns3::UniformRandomVariable::GetInteger(), ns3::MinstrelWifiRemoteStation::m_col, m_nsupported, m_sampleCol, m_sampleTable, m_uniformRandomVariable, and NS_LOG_DEBUG.

Referenced by CheckInit().

bool ns3::MinstrelWifiManager::IsLowLatency ( void ) const

privatevirtual

Returns: whether this manager is a manager designed to work in low-latency environments.

Note: In this context, low vs high latency is defined in IEEE 802.11 Rate Adaptation: A Practical Approach, by M. Lacage, M.H. Manshaei, and T. Turletti.

Implements ns3::WifiRemoteStationManager.

Definition at line 464 of file minstrel-wifi-manager.cc.

void ns3::MinstrelWifiManager::UpdateStats ( MinstrelWifiRemoteStation * station )

private

updating the Minstrel Table every 1/10 seconds

calculate the perfect tx time for this rate

just for initialization

if we've attempted something

calculate the probability of success assume probability scales from 0 to 18000

bookeeping

ewma probability (cast for gcc 3.4 compatibility)

calculating throughput

bookeeping

Sample less often below 10% and above 95% of success

retry count denotes the number of retries permitted for each rate

retry_count/2

if it's 0 allow one retry limit

go find max throughput, second maximum throughput, high probability succ

find the second highest max

reset it

Definition at line 577 of file minstrel-wifi-manager.cc.

References ns3::Time::GetMicroSeconds(), ns3::MinstrelWifiRemoteStation::m_currentRate, m_ewmaLevel, ns3::MinstrelWifiRemoteStation::m_initialized, ns3::MinstrelWifiRemoteStation::m_maxProbRate, ns3::MinstrelWifiRemoteStation::m_maxTpRate, ns3::MinstrelWifiRemoteStation::m_maxTpRate2, m_minstrelTable, ns3::MinstrelWifiRemoteStation::m_nextStatsUpdate, m_nsupported, ns3::MinstrelWifiRemoteStation::m_txrate, m_updateStats, ns3::Simulator::Now(), NS_LOG_DEBUG, RateInit(), and ns3::Seconds().

Referenced by DoGetDataMode().

The documentation for this class was generated from the following files:

src/wifi/model/minstrel-wifi-manager.h
src/wifi/model/minstrel-wifi-manager.cc

Public Member Functions

Static Public Member Functions

Private Types

Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Config Paths

Attributes

Attributes defined in parent class ns3::WifiRemoteStationManager

TraceSources defined in parent class ns3::WifiRemoteStationManager

Member Function Documentation

| random < best | random > best |

retry_count/2