inet::queueing::RedDropper Class Reference

Implementation of Random Early Detection (RED). More...

#include <RedDropper.h>

Inheritance diagram for inet::queueing::RedDropper:

Public Member Functions
virtual bool	matchesPacket (const Packet *packet) const override
	Returns true if the filter matches the given packet. More...
Public Member Functions inherited from inet::queueing::PacketFilterBase
virtual IPassivePacketSink *	getConsumer (cGate *gate) override
	Returns the passive packet sink where packets are pushed or nullptr if the connected module doesn't implement the interface. More...
virtual IPassivePacketSource *	getProvider (cGate *gate) override
	Returns the passive packet source from where packets are pulled or nullptr if the connected module doesn't implement the interface. More...
virtual bool	supportsPacketPushing (cGate *gate) const override
	Returns true if the processor supports pushing packets at the given gate. More...
virtual bool	supportsPacketPulling (cGate *gate) const override
	Returns true if the processor supports pulling packets at the given gate. More...
virtual bool	supportsPacketStreaming (cGate *gate) const override
	Returns true if the processor supports streaming packets at the given gate. More...
virtual bool	canPushSomePacket (cGate *gate) const override
	Returns false if the packet sink is full at the given gate and no more packets can be pushed into it without raising an error. More...
virtual bool	canPushPacket (Packet *packet, cGate *gate) const override
	Returns true if the given packet can be pushed at the given gate into the packet sink without raising an error. More...
virtual void	pushPacket (Packet *packet, cGate *gate) override
	Pushes the packet into the packet sink at the given gate. More...
virtual void	pushPacketStart (Packet *packet, cGate *gate, bps datarate) override
	Starts pushing the packet into the packet sink at the given gate. More...
virtual void	pushPacketEnd (Packet *packet, cGate *gate) override
	Ends pushing the packet into the packet sink at the given gate. More...
virtual void	pushPacketProgress (Packet *packet, cGate *gate, bps datarate, b position, b extraProcessableLength=b(0)) override
	Progresses pushing the packet into the packet sink at the given gate. More...
virtual void	handleCanPushPacketChanged (cGate *gate) override
	Notifies about a change in the possibility of pushing some packet into the passive packet sink at the given gate. More...
virtual void	handlePushPacketProcessed (Packet *packet, cGate *gate, bool successful) override
	Notifies about the completion of the packet processing for a packet that was pushed earlier independently whether the packet is passed or streamed. More...
virtual bool	canPullSomePacket (cGate *gate) const override
	Returns false if the packet source is empty at the given gate and no more packets can be pulled from it without raising an error. More...
virtual Packet *	canPullPacket (cGate *gate) const override
	Returns the packet that can be pulled at the given gate. More...
virtual Packet *	pullPacket (cGate *gate) override
	Pulls the packet from the packet source at the given gate. More...
virtual Packet *	pullPacketStart (cGate *gate, bps datarate) override
	Starts pulling the packet from the packet source at the given gate. More...
virtual Packet *	pullPacketEnd (cGate *gate) override
	Ends pulling the packet from the packet source at the given gate. More...
virtual Packet *	pullPacketProgress (cGate *gate, bps datarate, b position, b extraProcessableLength) override
	Progresses pulling the packet from the packet source at the given gate. More...
virtual void	handlePullPacketProcessed (Packet *packet, cGate *gate, bool successful) override
	Notifies about the completion of the packet processing for a packet that was pulled earlier independently whether the packet is passed or streamed. More...
virtual void	handleCanPullPacketChanged (cGate *gate) override
	Notifies about a change in the possibility of pulling some packet from the passive packet source at the given gate. More...
Public Member Functions inherited from inet::queueing::PacketProcessorBase
virtual bool	supportsPacketSending (cGate *gate) const override
	Returns true if the processor supports sending packets at the given gate. More...
virtual bool	supportsPacketPassing (cGate *gate) const override
	Returns true if the processor supports passing packets as a whole at the given gate. More...
Public Member Functions inherited from inet::queueing::IPacketProcessor
virtual	~IPacketProcessor ()
Public Member Functions inherited from inet::queueing::IPassivePacketSink
virtual	~IPassivePacketSink ()
Public Member Functions inherited from inet::queueing::IActivePacketSink
virtual	~IActivePacketSink ()
Public Member Functions inherited from inet::queueing::IPassivePacketSource
virtual	~IPassivePacketSource ()
Public Member Functions inherited from inet::queueing::IActivePacketSource
virtual	~IActivePacketSource ()

Protected Types
enum	RedResult {   QUEUE_FULL, RANDOMLY_ABOVE_LIMIT, RANDOMLY_BELOW_LIMIT, ABOVE_MAX_LIMIT,   BELOW_MIN_LIMIT }
Protected Types inherited from inet::queueing::PacketProcessorBase
enum	Action { PUSH, PULL }

Protected Member Functions
virtual void	initialize (int stage) override
virtual RedResult	doRandomEarlyDetection (const Packet *packet)
virtual void	processPacket (Packet *packet) override
virtual void	receiveSignal (cComponent *source, simsignal_t signalID, cObject *obj, cObject *details) override
Protected Member Functions inherited from inet::queueing::PacketFilterBase
virtual void	handleMessage (cMessage *message) override
virtual bool	isStreamingPacket () const
virtual void	startPacketStreaming (Packet *packet)
virtual void	endPacketStreaming (Packet *packet)
virtual void	checkPacketStreaming (Packet *packet)
virtual void	dropPacket (Packet *packet)
virtual void	dropPacket (Packet *packet, PacketDropReason reason, int limit=-1) override
virtual const char *	resolveDirective (char directive) const override
Protected Member Functions inherited from inet::queueing::PacketProcessorBase
virtual int	numInitStages () const override
virtual void	refreshDisplay () const override
virtual void	handlePacketProcessed (Packet *packet)
virtual void	checkPacketOperationSupport (cGate *gate) const
virtual void	checkPacketOperationSupport (cGate *startGate, cGate *endGate) const
virtual void	animate (Packet *packet, cGate *gate, const SendOptions &sendOptions, Action action) const
virtual void	animatePacket (Packet *packet, cGate *gate, Action action) const
virtual void	animatePacketStart (Packet *packet, cGate *gate, bps datarate, long transmissionId, Action action) const
virtual void	animatePacketStart (Packet *packet, cGate *gate, bps datarate, const SendOptions &sendOptions, Action action) const
virtual void	animatePacketEnd (Packet *packet, cGate *gate, long transmissionId, Action action) const
virtual void	animatePacketEnd (Packet *packet, cGate *gate, const SendOptions &sendOptions, Action action) const
virtual void	animatePacketProgress (Packet *packet, cGate *gate, bps datarate, b position, b extraProcessableLength, long transmissionId, Action action) const
virtual void	animatePacketProgress (Packet *packet, cGate *gate, bps datarate, b position, b extraProcessableLength, const SendOptions &sendOptions, Action action) const
virtual void	pushOrSendPacket (Packet *packet, cGate *gate, IPassivePacketSink *consumer)
virtual void	pushOrSendPacketStart (Packet *packet, cGate *gate, IPassivePacketSink *consumer, bps datarate, int transmissionId)
virtual void	pushOrSendPacketEnd (Packet *packet, cGate *gate, IPassivePacketSink *consumer, int transmissionId)
virtual void	pushOrSendPacketProgress (Packet *packet, cGate *gate, IPassivePacketSink *consumer, bps datarate, b position, b extraProcessableLength, int transmissionId)
virtual void	animatePush (Packet *packet, cGate *gate, const SendOptions &sendOptions) const
virtual void	animatePushPacket (Packet *packet, cGate *gate) const
virtual void	animatePushPacketStart (Packet *packet, cGate *gate, bps datarate, long transmissionId) const
virtual void	animatePushPacketStart (Packet *packet, cGate *gate, bps datarate, const SendOptions &sendOptions) const
virtual void	animatePushPacketEnd (Packet *packet, cGate *gate, long transmissionId) const
virtual void	animatePushPacketEnd (Packet *packet, cGate *gate, const SendOptions &sendOptions) const
virtual void	animatePushPacketProgress (Packet *packet, cGate *gate, bps datarate, b position, b extraProcessableLength, long transmissionId) const
virtual void	animatePushPacketProgress (Packet *packet, cGate *gate, bps datarate, b position, b extraProcessableLength, const SendOptions &sendOptions) const
virtual void	animatePull (Packet *packet, cGate *gate, const SendOptions &sendOptions) const
virtual void	animatePullPacket (Packet *packet, cGate *gate) const
virtual void	animatePullPacketStart (Packet *packet, cGate *gate, bps datarate, long transmissionId) const
virtual void	animatePullPacketStart (Packet *packet, cGate *gate, bps datarate, const SendOptions &sendOptions) const
virtual void	animatePullPacketEnd (Packet *packet, cGate *gate, long transmissionId) const
virtual void	animatePullPacketEnd (Packet *packet, cGate *gate, const SendOptions &sendOptions) const
virtual void	animatePullPacketProgress (Packet *packet, cGate *gate, bps datarate, b position, b extraProcessableLength, long transmissionId) const
virtual void	animatePullPacketProgress (Packet *packet, cGate *gate, bps datarate, b position, b extraProcessableLength, const SendOptions &sendOptions) const
virtual void	updateDisplayString () const

Protected Attributes
double	wq = 0.0
double	minth = NaN
double	maxth = NaN
double	maxp = NaN
double	pkrate = NaN
double	count = NaN
double	avg = 0.0
simtime_t	q_time
int	packetCapacity = -1
bool	useEcn = false
bool	markNext = false
RedResult	lastResult
ModuleRef< IPacketCollection >	collection
Protected Attributes inherited from inet::queueing::PacketFilterBase
bool	backpressure = false
cGate *	inputGate = nullptr
ModuleRef< IActivePacketSource >	producer
ModuleRef< IPassivePacketSource >	provider
cGate *	outputGate = nullptr
ModuleRef< IPassivePacketSink >	consumer
ModuleRef< IActivePacketSink >	collector
int	inProgressStreamId = -1
int	numDroppedPackets = 0
b	droppedTotalLength = b(-1)
Protected Attributes inherited from inet::queueing::PacketProcessorBase
const char *	displayStringTextFormat = nullptr
int	numProcessedPackets = -1
b	processedTotalLength = b(-1)

Detailed Description

Implementation of Random Early Detection (RED).

Member Enumeration Documentation

RedResult

enum inet::queueing::RedDropper::RedResult

protected

Enumerator
QUEUE_FULL
RANDOMLY_ABOVE_LIMIT
RANDOMLY_BELOW_LIMIT
ABOVE_MAX_LIMIT
BELOW_MIN_LIMIT

{ QUEUE_FULL, RANDOMLY_ABOVE_LIMIT, RANDOMLY_BELOW_LIMIT, ABOVE_MAX_LIMIT, BELOW_MIN_LIMIT };

Member Function Documentation

doRandomEarlyDetection()

RedDropper::RedResult inet::queueing::RedDropper::doRandomEarlyDetection ( const Packet *  packet )

protectedvirtual

{
    int queueLength = collection->getNumPackets();
 
    if (queueLength > 0) {
        // TD: This following calculation is only useful when the queue is not empty!
        avg = (1 - wq) * avg + wq * queueLength;
    }
    else {
        // TD: Added behaviour for empty queue.
        const double m = SIMTIME_DBL(simTime() - q_time) * pkrate;
        avg = pow(1 - wq, m) * avg;
        q_time = simTime();
    }
 
    if (queueLength >= packetCapacity) { // maxth is also the "hard" limit
        EV_DEBUG << "Queue length >= capacity" << EV_FIELD(queueLength) << EV_FIELD(packetCapacity) << EV_ENDL;
        count = 0;
        return QUEUE_FULL;
    }
    else if (minth <= avg && avg < maxth) {
        count++;
        const double pb = maxp * (avg - minth) / (maxth - minth);
        const double pa = pb / (1 - count * pb); // TD: Adapted to work as in [Floyd93].
        if (dblrand() < pa) {
            EV_DEBUG << "Random early packet detected" << EV_FIELD(averageQueueLength, avg) << EV_FIELD(probability, pa) << EV_ENDL;
            count = 0;
            return RANDOMLY_ABOVE_LIMIT;
        }
        else
            return RANDOMLY_BELOW_LIMIT;
    }
    else if (avg >= maxth) {
        EV_DEBUG << "Average queue length >= maxth" << EV_FIELD(averageQueueLength, avg) << EV_FIELD(maxth) << EV_ENDL;
        count = 0;
        return ABOVE_MAX_LIMIT;
    }
    else {
        count = -1;
    }
 
    return BELOW_MIN_LIMIT;
}

Referenced by matchesPacket().

initialize()

void inet::queueing::RedDropper::initialize ( int  stage )

overrideprotectedvirtual

Reimplemented from inet::queueing::PacketFilterBase.

{
    PacketFilterBase::initialize(stage);
 
    if (stage == INITSTAGE_LOCAL) {
        wq = par("wq");
        if (wq < 0.0 || wq > 1.0)
            throw cRuntimeError("Invalid value for wq parameter: %g", wq);
        minth = par("minth");
        maxth = par("maxth");
        maxp = par("maxp");
        pkrate = par("pkrate");
        count = -1;
        if (minth < 0.0)
            throw cRuntimeError("minth parameter must not be negative");
        if (maxth < 0.0)
            throw cRuntimeError("maxth parameter must not be negative");
        if (minth >= maxth)
            throw cRuntimeError("minth must be smaller than maxth");
        if (maxp < 0.0 || maxp > 1.0)
            throw cRuntimeError("Invalid value for maxp parameter: %g", maxp);
        if (pkrate < 0.0)
            throw cRuntimeError("Invalid value for pkrate parameter: %g", pkrate);
        useEcn = par("useEcn");
        packetCapacity = par("packetCapacity");
        if (maxth > packetCapacity)
            throw cRuntimeError("Warning: packetCapacity < maxth. Setting capacity to maxth");
        auto outputGate = gate("out");
        collection.reference(outputGate, false);
        if (!collection)
            collection.reference(this, "collectionModule", true);
        cModule * cm = check_and_cast<cModule *>(collection.get());
        cm->subscribe(packetPushedSignal, this);
        cm->subscribe(packetPulledSignal, this);
        cm->subscribe(packetRemovedSignal, this);
        cm->subscribe(packetDroppedSignal, this);
    }
}

matchesPacket()

bool inet::queueing::RedDropper::matchesPacket ( const Packet *  packet ) const

overridevirtual

Returns true if the filter matches the given packet.

Implements inet::queueing::IPacketFilter.

{
    lastResult = const_cast<RedDropper *>(this)->doRandomEarlyDetection(packet);
    switch (lastResult) {
        case RANDOMLY_ABOVE_LIMIT:
        case ABOVE_MAX_LIMIT:
            return useEcn && EcnMarker::getEcn(packet) != IP_ECN_NOT_ECT;
        case RANDOMLY_BELOW_LIMIT:
        case BELOW_MIN_LIMIT:
            return true;
        case QUEUE_FULL:
            return false;
        default:
            throw cRuntimeError("Unknown RED result");
    }
}

processPacket()

void inet::queueing::RedDropper::processPacket ( Packet *  packet )

overrideprotectedvirtual

Reimplemented from inet::queueing::PacketFilterBase.

{
    switch (lastResult) {
        case RANDOMLY_ABOVE_LIMIT:
        case ABOVE_MAX_LIMIT: {
            if (useEcn) {
                IpEcnCode ecn = EcnMarker::getEcn(packet);
                if (ecn != IP_ECN_NOT_ECT) {
                    // if next packet should be marked and it is not
                    if (markNext && ecn != IP_ECN_CE) {
                        EcnMarker::setEcn(packet, IP_ECN_CE);
                        markNext = false;
                    }
                    else {
                        if (ecn == IP_ECN_CE)
                            markNext = true;
                        else
                            EcnMarker::setEcn(packet, IP_ECN_CE);
                    }
                }
            }
        }
        case RANDOMLY_BELOW_LIMIT:
        case BELOW_MIN_LIMIT:
        case QUEUE_FULL:
            break;
        default:
            throw cRuntimeError("Unknown RED result");
    }
}

receiveSignal()

void inet::queueing::RedDropper::receiveSignal ( cComponent *  source, simsignal_t  signalID, cObject *  obj, cObject *  details  )

overrideprotectedvirtual

{
    if (signalID == packetPushedSignal || signalID == packetPulledSignal || signalID == packetRemovedSignal || signalID == packetDroppedSignal)
        q_time = simTime();
}

Member Data Documentation

avg

double inet::queueing::RedDropper::avg = 0.0

protected

Referenced by doRandomEarlyDetection().

collection

ModuleRef<IPacketCollection> inet::queueing::RedDropper::collection

protected

Referenced by doRandomEarlyDetection(), and initialize().

count

double inet::queueing::RedDropper::count = NaN

protected

Referenced by doRandomEarlyDetection(), and initialize().

lastResult

RedResult inet::queueing::RedDropper::lastResult

mutableprotected

Referenced by matchesPacket(), and processPacket().

markNext

bool inet::queueing::RedDropper::markNext = false

protected

Referenced by processPacket().

maxp

double inet::queueing::RedDropper::maxp = NaN

protected

Referenced by doRandomEarlyDetection(), and initialize().

maxth

double inet::queueing::RedDropper::maxth = NaN

protected

Referenced by doRandomEarlyDetection(), and initialize().

minth

double inet::queueing::RedDropper::minth = NaN

protected

Referenced by doRandomEarlyDetection(), and initialize().

packetCapacity

int inet::queueing::RedDropper::packetCapacity = -1

protected

Referenced by doRandomEarlyDetection(), and initialize().

pkrate

double inet::queueing::RedDropper::pkrate = NaN

protected

Referenced by doRandomEarlyDetection(), and initialize().

q_time

simtime_t inet::queueing::RedDropper::q_time

protected

Referenced by doRandomEarlyDetection(), and receiveSignal().

useEcn

bool inet::queueing::RedDropper::useEcn = false

protected

Referenced by initialize(), matchesPacket(), and processPacket().

wq

double inet::queueing::RedDropper::wq = 0.0

protected

Referenced by doRandomEarlyDetection(), and initialize().

---

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

• RedDropper.h
• RedDropper.cc