ieee80211: make rate control adapt per receiver, add per-receiver configured rates

src/inet/linklayer/ieee80211/mac/contract/IRateControl.h

@@ -9,6 +9,7 @@
 #define __INET_IRATECONTROL_H
 
 #include "inet/common/packet/Packet.h"
+#include "inet/linklayer/common/MacAddress.h"
 #include "inet/linklayer/ieee80211/mac/Ieee80211Frame_m.h"
 #include "inet/physicallayer/wireless/ieee80211/mode/Ieee80211ModeSet.h"
 #include "inet/physicallayer/wireless/ieee80211/packetlevel/Ieee80211ControlInfo_m.h"
@@ -25,7 +26,8 @@ class INET_API IRateControl
   public:
     virtual ~IRateControl() {}
 
-    virtual const physicallayer::IIeee80211Mode *getRate() = 0;
+    // Returns the rate to use for a unicast frame addressed to the given receiver.
+    virtual const physicallayer::IIeee80211Mode *getRate(const MacAddress& receiverAddress) = 0;
     virtual void frameTransmitted(Packet *frame, int retryCount, bool isSuccessful, bool isGivenUp) = 0;
     virtual void frameReceived(Packet *frame) = 0;
 };

src/inet/linklayer/ieee80211/mac/contract/IRateSelection.cc

@@ -7,11 +7,27 @@
 
 #include "inet/linklayer/ieee80211/mac/contract/IRateSelection.h"
 
+#include "inet/networklayer/common/L3AddressResolver.h"
+
 namespace inet {
 namespace ieee80211 {
 
+using namespace inet::physicallayer;
+
 simsignal_t IRateSelection::datarateSelectedSignal = cComponent::registerSignal("datarateSelected");
 
+void IRateSelection::emitDatarateSelected(cComponent *emitter, const Ptr<const Ieee80211MacHeader>& header, const IIeee80211Mode *mode)
+{
+    double rate = mode->getDataMode()->getNetBitrate().get<bps>();
+    auto dataHeader = dynamicPtrCast<const Ieee80211DataHeader>(header);
+    // naming the station sweeps the network, so skip it if nothing listens anyway
+    if (dataHeader != nullptr && !dataHeader->getReceiverAddress().isMulticast() && emitter->mayHaveListeners(datarateSelectedSignal)) {
+        cNamedObject details(L3AddressResolver().getHostNameWithMacAddress(dataHeader->getReceiverAddress()).c_str());
+        emitter->emit(datarateSelectedSignal, rate, &details);
+    }
+    else
+        emitter->emit(datarateSelectedSignal, rate);
+}
+
 } // namespace ieee80211
 } // namespace inet
-

src/inet/linklayer/ieee80211/mac/contract/IRateSelection.h

@@ -26,6 +26,16 @@ class INET_API IRateSelection
   public:
     static simsignal_t datarateSelectedSignal;
 
+    // Emits datarateSelected on behalf of a coordination function. Unicast data frames are tagged
+    // with the name of the receiving station as a named details object, so that a
+    // demux(datarateSelected) result filter or a statistic visualizer can key a separate
+    // per-station series on it; this mirrors the condition under which ~RateSelection applies a
+    // per-receiver configured rate, so the details always name the station whose rate is
+    // reported. Control, management and group-addressed frames carry no per-station data rate and
+    // are emitted without details: the aggregate datarateSelected statistic still records them, a
+    // bar chart ignores them.
+    static void emitDatarateSelected(cComponent *emitter, const Ptr<const Ieee80211MacHeader>& header, const physicallayer::IIeee80211Mode *mode);
+
   public:
     virtual ~IRateSelection() {}
 

src/inet/linklayer/ieee80211/mac/coordinationfunction/Dcf.cc

@@ -102,7 +102,7 @@ void Dcf::transmitControlResponseFrame(Packet *responsePacket, const Ptr<const I
     else
         throw cRuntimeError("Unknown received frame type");
     RateSelection::setFrameMode(responsePacket, responseHeader, responseMode);
-    emit(IRateSelection::datarateSelectedSignal, responseMode->getDataMode()->getNetBitrate().get<bps>(), responsePacket);
+    IRateSelection::emitDatarateSelected(this, responseHeader, responseMode);
     EV_DEBUG << "Datarate for " << responsePacket->getName() << " is set to " << responseMode->getDataMode()->getNetBitrate() << ".\n";
     tx->transmitFrame(responsePacket, responseHeader, modeSet->getSifsTime(), this);
     delete responsePacket;
@@ -166,7 +166,7 @@ void Dcf::transmitFrame(Packet *packet, simtime_t ifs)
     const auto& header = packet->peekAtFront<Ieee80211MacHeader>();
     auto mode = rateSelection->computeMode(packet, header);
     RateSelection::setFrameMode(packet, header, mode);
-    emit(IRateSelection::datarateSelectedSignal, mode->getDataMode()->getNetBitrate().get<bps>(), packet);
+    IRateSelection::emitDatarateSelected(this, header, mode);
     EV_DEBUG << "Datarate for " << packet->getName() << " is set to " << mode->getDataMode()->getNetBitrate() << ".\n";
     auto pendingPacket = channelAccess->getInProgressFrames()->getPendingFrameFor(packet);
     auto duration = originatorProtectionMechanism->computeDurationField(packet, header, pendingPacket, pendingPacket == nullptr ? nullptr : pendingPacket->peekAtFront<Ieee80211DataOrMgmtHeader>());

src/inet/linklayer/ieee80211/mac/coordinationfunction/Hcf.cc

@@ -668,7 +668,7 @@ void Hcf::transmitFrame(Packet *packet, simtime_t ifs)
         }
         auto mode = rateSelection->computeMode(packet, header, txop);
         setFrameMode(packet, header, mode);
-        emit(IRateSelection::datarateSelectedSignal, mode->getDataMode()->getNetBitrate().get<bps>(), packet);
+        IRateSelection::emitDatarateSelected(this, header, mode);
         EV_DEBUG << "Datarate for " << packet->getName() << " is set to " << mode->getDataMode()->getNetBitrate() << ".\n";
         if (txop->getProtectionMechanism() == TxopProcedure::ProtectionMechanism::SINGLE_PROTECTION) {
             auto pendingPacket = channelOwner->getInProgressFrames()->getPendingFrameFor(packet);
@@ -703,7 +703,7 @@ void Hcf::transmitControlResponseFrame(Packet *responsePacket, const Ptr<const I
     else
         throw cRuntimeError("Unknown received frame type");
     setFrameMode(responsePacket, responseHeader, responseMode);
-    emit(IRateSelection::datarateSelectedSignal, responseMode->getDataMode()->getNetBitrate().get<bps>(), responsePacket);
+    IRateSelection::emitDatarateSelected(this, responseHeader, responseMode);
     EV_DEBUG << "Datarate for " << responsePacket->getName() << " is set to " << responseMode->getDataMode()->getNetBitrate() << ".\n";
     tx->transmitFrame(responsePacket, responseHeader, modeSet->getSifsTime(), this);
     delete responsePacket;

src/inet/linklayer/ieee80211/mac/originator/TxopProcedure.cc

@@ -96,7 +96,7 @@ simtime_t TxopProcedure::getRemaining() const
     if (start == -1)
         throw cRuntimeError("Txop has not started yet");
     auto now = simTime();
-    return now > start + limit ? 0 : now - start;
+    return now > start + limit ? 0 : start + limit - now;
 }
 
 simtime_t TxopProcedure::getDuration() const

src/inet/linklayer/ieee80211/mac/ratecontrol/AarfRateControl.cc

@@ -19,18 +19,14 @@ void AarfRateControl::initialize(int stage)
     RateControlBase::initialize(stage);
     if (stage == INITSTAGE_LOCAL) {
         factor = par("increaseThresholdFactor");
-        increaseThreshold = par("increaseThreshold");
         maxIncreaseThreshold = par("maxIncreaseThreshold");
         decreaseThreshold = par("decreaseThreshold");
         interval = par("interval");
+        WATCH_EXPR("numStations", (int)stations.size());
         WATCH(factor);
-        WATCH(increaseThreshold);
         WATCH(maxIncreaseThreshold);
         WATCH(decreaseThreshold);
         WATCH(interval);
-        WATCH(timer);
-        WATCH(probing);
-        WATCH(numberOfConsSuccTransmissions);
     }
     else if (stage == INITSTAGE_LINK_LAYER) {
     }
@@ -41,80 +37,96 @@ void AarfRateControl::handleMessage(cMessage *msg)
     throw cRuntimeError("This module doesn't handle self messages");
 }
 
+
+AarfRateControl::State& AarfRateControl::stateFor(const MacAddress& receiverAddress)
+{
+    auto it = stations.find(receiverAddress);
+    if (it == stations.end()) {
+        State state;
+        state.address = receiverAddress;
+        state.mode = getInitialMode();
+        state.increaseThreshold = par("increaseThreshold");
+        state.timer = simTime(); // the interval starts when the station is first seen, not at t=0
+        it = stations.insert({receiverAddress, state}).first;
+        emitDatarateChangedSignal(state.address, state.mode);
+    }
+    return it->second;
+}
+
 void AarfRateControl::frameTransmitted(Packet *frame, int retryCount, bool isSuccessful, bool isGivenUp)
 {
-    increaseRateIfTimerIsExpired();
-
-    if (!isSuccessful && probing) { // probing packet failed
-        numberOfConsSuccTransmissions = 0;
-        currentMode = decreaseRateIfPossible(currentMode);
-        emitDatarateChangedSignal();
-        EV_DETAIL << "Decreased rate to " << *currentMode << endl;
-        multiplyIncreaseThreshold(factor);
-        resetTimer();
+    State& state = stateFor(getReceiverAddress(frame));
+    increaseRateIfTimerIsExpired(state);
+
+    if (!isSuccessful && state.probing) { // probing packet failed
+        state.numberOfConsSuccTransmissions = 0;
+        state.mode = decreaseRateIfPossible(state.mode);
+        emitDatarateChangedSignal(state.address, state.mode);
+        EV_DETAIL << "Decreased rate to " << *state.mode << endl;
+        multiplyIncreaseThreshold(state, factor);
+        resetTimer(state);
     }
     else if (!isSuccessful && retryCount >= decreaseThreshold - 1) { // decreaseThreshold consecutive failed transmissions
-        numberOfConsSuccTransmissions = 0;
-        currentMode = decreaseRateIfPossible(currentMode);
-        emitDatarateChangedSignal();
-        EV_DETAIL << "Decreased rate to " << *currentMode << endl;
-        resetIncreaseThreshdold();
-        resetTimer();
+        state.numberOfConsSuccTransmissions = 0;
+        state.mode = decreaseRateIfPossible(state.mode);
+        emitDatarateChangedSignal(state.address, state.mode);
+        EV_DETAIL << "Decreased rate to " << *state.mode << endl;
+        resetIncreaseThreshdold(state);
+        resetTimer(state);
     }
     else if (isSuccessful && retryCount == 0)
-        numberOfConsSuccTransmissions++;
-
-    if (numberOfConsSuccTransmissions == increaseThreshold) {
-        numberOfConsSuccTransmissions = 0;
-        currentMode = increaseRateIfPossible(currentMode);
-        emitDatarateChangedSignal();
-        EV_DETAIL << "Increased rate to " << *currentMode << endl;
-        resetTimer();
-        probing = true;
+        state.numberOfConsSuccTransmissions++;
+
+    if (state.numberOfConsSuccTransmissions == state.increaseThreshold) {
+        state.numberOfConsSuccTransmissions = 0;
+        state.mode = increaseRateIfPossible(state.mode);
+        emitDatarateChangedSignal(state.address, state.mode);
+        EV_DETAIL << "Increased rate to " << *state.mode << endl;
+        resetTimer(state);
+        state.probing = true;
     }
     else
-        probing = false;
-
+        state.probing = false;
 }
 
-void AarfRateControl::multiplyIncreaseThreshold(double factor)
+void AarfRateControl::multiplyIncreaseThreshold(State& state, double factor)
 {
-    if (increaseThreshold * factor <= maxIncreaseThreshold)
-        increaseThreshold *= factor;
+    if (state.increaseThreshold * factor <= maxIncreaseThreshold)
+        state.increaseThreshold *= factor;
 }
 
-void AarfRateControl::resetIncreaseThreshdold()
+void AarfRateControl::resetIncreaseThreshdold(State& state)
 {
-    increaseThreshold = par("increaseThreshold");
+    state.increaseThreshold = par("increaseThreshold");
 }
 
-void AarfRateControl::resetTimer()
+void AarfRateControl::resetTimer(State& state)
 {
-    timer = simTime();
+    state.timer = simTime();
 }
 
-void AarfRateControl::increaseRateIfTimerIsExpired()
+void AarfRateControl::increaseRateIfTimerIsExpired(State& state)
 {
-    if (simTime() - timer >= interval) {
-        currentMode = increaseRateIfPossible(currentMode);
-        emitDatarateChangedSignal();
-        EV_DETAIL << "Increased rate to " << *currentMode << endl;
-        resetTimer();
+    if (simTime() - state.timer >= interval) {
+        state.mode = increaseRateIfPossible(state.mode);
+        emitDatarateChangedSignal(state.address, state.mode);
+        EV_DETAIL << "Increased rate to " << *state.mode << endl;
+        resetTimer(state);
     }
 }
 
 void AarfRateControl::frameReceived(Packet *frame)
 {
 }
 
-const IIeee80211Mode *AarfRateControl::getRate()
+const IIeee80211Mode *AarfRateControl::getRate(const MacAddress& receiverAddress)
 {
     Enter_Method("getRate");
-    increaseRateIfTimerIsExpired();
-    EV_INFO << "The current mode is " << currentMode << " the net bitrate is " << currentMode->getDataMode()->getNetBitrate() << std::endl;
-    return currentMode;
+    State& state = stateFor(receiverAddress);
+    increaseRateIfTimerIsExpired(state);
+    EV_INFO << "The current mode is " << state.mode << " the net bitrate is " << state.mode->getDataMode()->getNetBitrate() << std::endl;
+    return state.mode;
 }
 
 } /* namespace ieee80211 */
 } /* namespace inet */
-

src/inet/linklayer/ieee80211/mac/ratecontrol/AarfRateControl.h

@@ -19,28 +19,38 @@ namespace ieee80211 {
 class INET_API AarfRateControl : public RateControlBase
 {
   protected:
-    simtime_t timer = SIMTIME_ZERO;
+    // Per-receiver adaptive state (formerly single-instance module members).
+    struct State {
+        MacAddress address; // the receiver this state belongs to (for per-station rate attribution)
+        const physicallayer::IIeee80211Mode *mode = nullptr;
+        simtime_t timer = SIMTIME_ZERO;
+        bool probing = false;
+        int increaseThreshold = -1;
+        int numberOfConsSuccTransmissions = 0;
+    };
+    std::map<MacAddress, State> stations;
+
+    // configuration, shared across stations
     simtime_t interval = SIMTIME_ZERO;
-    bool probing = false;
-    int increaseThreshold = -1;
     int maxIncreaseThreshold = -1;
     int decreaseThreshold = -1;
     double factor = -1;
 
-    int numberOfConsSuccTransmissions = 0;
-
   protected:
     virtual int numInitStages() const override { return NUM_INIT_STAGES; }
     virtual void initialize(int stage) override;
     virtual void handleMessage(cMessage *msg) override;
 
-    virtual void multiplyIncreaseThreshold(double factor);
-    virtual void resetIncreaseThreshdold();
-    virtual void resetTimer();
-    virtual void increaseRateIfTimerIsExpired();
+    virtual State& stateFor(const MacAddress& receiverAddress);
+    virtual void resetRateControl() override { stations.clear(); }
+
+    virtual void multiplyIncreaseThreshold(State& state, double factor);
+    virtual void resetIncreaseThreshdold(State& state);
+    virtual void resetTimer(State& state);
+    virtual void increaseRateIfTimerIsExpired(State& state);
 
   public:
-    virtual const physicallayer::IIeee80211Mode *getRate() override;
+    virtual const physicallayer::IIeee80211Mode *getRate(const MacAddress& receiverAddress) override;
     virtual void frameTransmitted(Packet *frame, int retryCount, bool isSuccessful, bool isGivenUp) override;
     virtual void frameReceived(Packet *frame) override;
 };

src/inet/linklayer/ieee80211/mac/ratecontrol/AarfRateControl.ned

@@ -26,9 +26,10 @@ simple AarfRateControl extends SimpleModule like IRateControl
                                             // needed to increase the rate
         double increaseThresholdFactor = default(2); // When the transmission of the probing packet fails, increaseThreshold is multiplied by increaseThresholdFactor.
         int maxIncreaseThreshold = default(50); // Upper bound for increaseThreshold.
-        displayStringTextFormat = default("{currentMode}");
+        displayStringTextFormat = default("{numStations} stations");
         @display("i=block/cogwheel");
         @signal[datarateChanged];
-        @statistic[datarateChanged](title="datarate"; record=vector; interpolationmode=sample-hold);
+        @statistic[datarateChanged](title="datarate"; record=vector; interpolationmode=sample-hold); // aggregate rate over all stations (interleaved)
+        @statistic[dataratePerStation](title="data rate per station"; source=demux(datarateChanged); unit=bps; record=vector; interpolationmode=sample-hold); // one vector per receiver, demultiplexed by station
 }