fix(ieee80211): correct Block Ack receive-window handling

Make BlockAckRecord the authoritative owner of WinStartR and update the scoreboard for every successfully received related Data MPDU. Advance it from newer Data frames and BlockAckReq starting sequence numbers instead of coupling acknowledgment state to upward packet delivery.

Fix empty Basic Block Ack records so current-window sequence and fragment entries are reported as unacknowledged while entries older than WinStartR remain acknowledged.

Keep the reordering window independent from the acknowledgment window. When a future MPDU or BAR advances the window, deliver complete displaced MSDUs, discard incomplete stale entries, retain packets beyond gaps, and preserve cyclic delivery order across the 4095-to-0 boundary. Detach returned packets before deleting stale receive-buffer state.

Replace the station-wide compressed Block Ack assumption with capability state stored per agreement. Derive it from explicit local support and a configured peer-address list until HT Capabilities elements are modeled. Use compressed BAR only for established immediate agreements that support it, and suppress compressed Block Ack responses when no agreement exists.

Add focused unit and runtime coverage for Basic and Compressed bitmaps, Data- and BAR-driven window movement, wraparound, gaps, fragments, duplicates, ownership, Normal Ack reception, capability gating, null responses, serialization, and the BAR-to-BA exchange.

Multi-TID Block Ack remains unsupported. BA Control bit 0 remains clear because it is reserved by IEEE 802.11-2024, rather than a BA Ack Policy bit.

Fingerprint validation found five expected maintained-ingredient changes in QoS and Block Ack scenarios. The three previously retained tyf values were also rechecked and found stale. Fingerprint CSV updates are intentionally not included pending separate approval.

Author: mgonzalezlopezudc

src/inet/linklayer/ieee80211/mac/blockack/BlockAckRecord.cc

@@ -19,10 +19,14 @@ BlockAckRecord::BlockAckRecord(MacAddress originatorAddress, Tid tid, SequenceNu
 {
 }
 
-void BlockAckRecord::blockAckPolicyFrameReceived(const Ptr<const Ieee80211DataHeader>& header)
+void BlockAckRecord::dataFrameReceived(const Ptr<const Ieee80211DataHeader>& header, int windowSize)
 {
     SequenceNumberCyclic sequenceNumber = header->getSequenceNumber();
     FragmentNumber fragmentNumber = header->getFragmentNumber();
+    // IEEE Std 802.11-2024, 10.25.6.3(b) and 10.25.6.4(c): a related
+    // MPDU beyond WinEndR advances the receive window before its bit is set.
+    if (startingSequenceNumber + windowSize <= sequenceNumber && sequenceNumber < startingSequenceNumber + 2048)
+        advanceStartingSequenceNumber(sequenceNumber - windowSize + 1);
     acknowledgmentState[SequenceControlField(sequenceNumber.get(), fragmentNumber)] = true;
 }
 
@@ -31,16 +35,7 @@ bool BlockAckRecord::getAckState(SequenceNumberCyclic sequenceNumber, FragmentNu
     // The status of MPDUs that are considered “old” and prior to the sequence number
     // range for which the receiver maintains status shall be reported as successfully
     // received (i.e., the corresponding bit in the bitmap shall be set to 1).
-    if (containsKey(acknowledgmentState, SequenceControlField(sequenceNumber.get(), fragmentNumber))) {
-        return true;
-    }
-    else if (acknowledgmentState.size() == 0) {
-        return true; // TODO old?
-    }
-    else {
-        auto earliest = acknowledgmentState.begin();
-        return SequenceNumberCyclic(earliest->first.getSequenceNumber()) > sequenceNumber; // old = true
-    }
+    return containsKey(acknowledgmentState, SequenceControlField(sequenceNumber.get(), fragmentNumber)) || sequenceNumber < startingSequenceNumber;
 }
 
 bool BlockAckRecord::getCompressedAckState(SequenceNumberCyclic sequenceNumber)
@@ -50,17 +45,20 @@ bool BlockAckRecord::getCompressedAckState(SequenceNumberCyclic sequenceNumber)
     return containsKey(acknowledgmentState, SequenceControlField(sequenceNumber.get(), 0)) || sequenceNumber < startingSequenceNumber;
 }
 
-void BlockAckRecord::removeAckStates(SequenceNumberCyclic sequenceNumber)
+void BlockAckRecord::advanceStartingSequenceNumber(SequenceNumberCyclic newStartingSequenceNumber)
 {
+    // IEEE Std 802.11-2024, 10.25.6.3 and 10.25.6.4: advance WinStartR
+    // for a newer related MPDU or BAR SSN, using the 12-bit sequence space.
+    if (!(startingSequenceNumber < newStartingSequenceNumber))
+        return;
     auto it = acknowledgmentState.begin();
     while (it != acknowledgmentState.end()) {
-        if (SequenceNumberCyclic(it->first.getSequenceNumber()) < sequenceNumber)
+        if (SequenceNumberCyclic(it->first.getSequenceNumber()) < newStartingSequenceNumber)
             it = acknowledgmentState.erase(it);
         else
             it++;
     }
-    if (startingSequenceNumber <= sequenceNumber)
-        startingSequenceNumber = sequenceNumber + 1;
+    startingSequenceNumber = newStartingSequenceNumber;
 }
 
 } /* namespace ieee80211 */

src/inet/linklayer/ieee80211/mac/blockack/BlockAckRecord.h

@@ -31,13 +31,14 @@ class INET_API BlockAckRecord
     BlockAckRecord(MacAddress originatorAddress, Tid tid, SequenceNumberCyclic startingSequenceNumber);
     virtual ~BlockAckRecord() {}
 
-    void blockAckPolicyFrameReceived(const Ptr<const Ieee80211DataHeader>& header);
+    void dataFrameReceived(const Ptr<const Ieee80211DataHeader>& header, int windowSize);
     bool getAckState(SequenceNumberCyclic sequenceNumber, FragmentNumber fragmentNumber);
     bool getCompressedAckState(SequenceNumberCyclic sequenceNumber);
-    void removeAckStates(SequenceNumberCyclic sequenceNumber);
+    void advanceStartingSequenceNumber(SequenceNumberCyclic startingSequenceNumber);
 
     MacAddress getOriginatorAddress() { return originatorAddress; }
     Tid getTid() { return tid; }
+    SequenceNumberCyclic getStartingSequenceNumber() const { return startingSequenceNumber; }
 };
 
 } /* namespace ieee80211 */

src/inet/linklayer/ieee80211/mac/blockack/OriginatorBlockAckAgreement.h

@@ -25,19 +25,21 @@ class INET_API OriginatorBlockAckAgreement : public cObject
     int bufferSize = -1;
     bool isAMsduSupported = false;
     bool isDelayedBlockAckPolicySupported = false;
+    bool isCompressedBlockAckSupported = false;
     bool isAddbaResponseReceived = false;
     bool isAddbaRequestSent = false;
     simtime_t blockAckTimeoutValue = -1;
     simtime_t expirationTime = -1;
 
   public:
-    OriginatorBlockAckAgreement(MacAddress receiverAddr, Tid tid, SequenceNumberCyclic startingSequenceNumber, int bufferSize, bool isAMsduSupported, bool isDelayedBlockAckPolicySupported) :
+    OriginatorBlockAckAgreement(MacAddress receiverAddr, Tid tid, SequenceNumberCyclic startingSequenceNumber, int bufferSize, bool isAMsduSupported, bool isDelayedBlockAckPolicySupported, bool isCompressedBlockAckSupported = false) :
         receiverAddr(receiverAddr),
         tid(tid),
         startingSequenceNumber(startingSequenceNumber),
         bufferSize(bufferSize),
         isAMsduSupported(isAMsduSupported),
-        isDelayedBlockAckPolicySupported(isDelayedBlockAckPolicySupported)
+        isDelayedBlockAckPolicySupported(isDelayedBlockAckPolicySupported),
+        isCompressedBlockAckSupported(isCompressedBlockAckSupported)
     {
     }
 
@@ -50,6 +52,7 @@ class INET_API OriginatorBlockAckAgreement : public cObject
     virtual bool getIsAddbaRequestSent() const { return isAddbaRequestSent; }
     virtual bool getIsAMsduSupported() const { return isAMsduSupported; }
     virtual bool getIsDelayedBlockAckPolicySupported() const { return isDelayedBlockAckPolicySupported; }
+    virtual bool getIsCompressedBlockAckSupported() const { return isCompressedBlockAckSupported; }
     virtual MacAddress getReceiverAddr() const { return receiverAddr; }
     virtual Tid getTid() const { return tid; }
     virtual const simtime_t getBlockAckTimeoutValue() const { return blockAckTimeoutValue; }
@@ -60,6 +63,7 @@ class INET_API OriginatorBlockAckAgreement : public cObject
     virtual void setIsAddbaRequestSent(bool isAddbaRequestSent) { this->isAddbaRequestSent = isAddbaRequestSent; }
     virtual void setIsAMsduSupported(bool isAMsduSupported) { this->isAMsduSupported = isAMsduSupported; }
     virtual void setIsDelayedBlockAckPolicySupported(bool isDelayedBlockAckPolicySupported) { this->isDelayedBlockAckPolicySupported = isDelayedBlockAckPolicySupported; }
+    virtual void setIsCompressedBlockAckSupported(bool isCompressedBlockAckSupported) { this->isCompressedBlockAckSupported = isCompressedBlockAckSupported; }
     virtual void setBlockAckTimeoutValue(const simtime_t blockAckTimeoutValue) { this->blockAckTimeoutValue = blockAckTimeoutValue; }
 
     virtual void baPolicyFrameSent() { numSentBaPolicyFrames++; }
@@ -71,4 +75,3 @@ class INET_API OriginatorBlockAckAgreement : public cObject
 } /* namespace inet */
 
 #endif
-

src/inet/linklayer/ieee80211/mac/blockack/OriginatorBlockAckAgreementHandler.cc

@@ -12,9 +12,10 @@
 namespace inet {
 namespace ieee80211 {
 
-void OriginatorBlockAckAgreementHandler::createAgreement(const Ptr<const Ieee80211AddbaRequest>& addbaRequest)
+void OriginatorBlockAckAgreementHandler::createAgreement(const Ptr<const Ieee80211AddbaRequest>& addbaRequest, IOriginatorBlockAckAgreementPolicy *blockAckAgreementPolicy)
 {
-    OriginatorBlockAckAgreement *blockAckAgreement = new OriginatorBlockAckAgreement(addbaRequest->getReceiverAddress(), addbaRequest->getTid(), addbaRequest->getStartingSequenceNumber(), addbaRequest->getBufferSize(), addbaRequest->getAMsduSupported(), addbaRequest->getBlockAckPolicy() == 0);
+    bool isCompressedBlockAckSupported = blockAckAgreementPolicy->isPeerCompressedBlockAckSupported(addbaRequest->getReceiverAddress());
+    OriginatorBlockAckAgreement *blockAckAgreement = new OriginatorBlockAckAgreement(addbaRequest->getReceiverAddress(), addbaRequest->getTid(), addbaRequest->getStartingSequenceNumber(), addbaRequest->getBufferSize(), addbaRequest->getAMsduSupported(), addbaRequest->getBlockAckPolicy() == 0, isCompressedBlockAckSupported);
     auto agreementId = std::make_pair(addbaRequest->getReceiverAddress(), addbaRequest->getTid());
     blockAckAgreements[agreementId] = blockAckAgreement;
 }
@@ -134,7 +135,7 @@ void OriginatorBlockAckAgreementHandler::processTransmittedDataFrame(Packet *pac
     auto agreement = getAgreement(dataHeader->getReceiverAddress(), dataHeader->getTid());
     if (blockAckAgreementPolicy->isAddbaReqNeeded(packet, dataHeader) && agreement == nullptr) {
         auto addbaReq = buildAddbaRequest(dataHeader->getReceiverAddress(), dataHeader->getTid(), dataHeader->getSequenceNumber() + 1, blockAckAgreementPolicy);
-        createAgreement(addbaReq);
+        createAgreement(addbaReq, blockAckAgreementPolicy);
         auto addbaPacket = new Packet("AddbaReq", addbaReq);
         callback->processMgmtFrame(addbaPacket, addbaReq);
     }
@@ -144,20 +145,21 @@ void OriginatorBlockAckAgreementHandler::processReceivedAddbaResp(const Ptr<cons
 {
     auto agreement = getAgreement(addbaResp->getTransmitterAddress(), addbaResp->getTid());
     if (blockAckAgreementPolicy->isAddbaReqAccepted(addbaResp, agreement)) {
-        updateAgreement(agreement, addbaResp);
+        updateAgreement(agreement, addbaResp, blockAckAgreementPolicy);
         scheduleInactivityTimer(callback);
     }
     else {
         // TODO send a new one?
     }
 }
 
-void OriginatorBlockAckAgreementHandler::updateAgreement(OriginatorBlockAckAgreement *agreement, const Ptr<const Ieee80211AddbaResponse>& addbaResp)
+void OriginatorBlockAckAgreementHandler::updateAgreement(OriginatorBlockAckAgreement *agreement, const Ptr<const Ieee80211AddbaResponse>& addbaResp, IOriginatorBlockAckAgreementPolicy *blockAckAgreementPolicy)
 {
     agreement->setIsAddbaResponseReceived(true);
     agreement->setIsDelayedBlockAckPolicySupported(addbaResp->getBlockAckPolicy() == 0);
     agreement->setBufferSize(addbaResp->getBufferSize());
     agreement->setBlockAckTimeoutValue(addbaResp->getBlockAckTimeoutValue());
+    agreement->setIsCompressedBlockAckSupported(blockAckAgreementPolicy->isPeerCompressedBlockAckSupported(addbaResp->getTransmitterAddress()));
     agreement->calculateExpirationTime();
 }
 

src/inet/linklayer/ieee80211/mac/blockack/OriginatorBlockAckAgreementHandler.h

@@ -24,8 +24,8 @@ class INET_API OriginatorBlockAckAgreementHandler : public IOriginatorBlockAckAg
 
   protected:
     virtual const Ptr<Ieee80211AddbaRequest> buildAddbaRequest(MacAddress receiverAddr, Tid tid, SequenceNumberCyclic startingSequenceNumber, IOriginatorBlockAckAgreementPolicy *blockAckAgreementPolicy);
-    virtual void createAgreement(const Ptr<const Ieee80211AddbaRequest>& addbaRequest);
-    virtual void updateAgreement(OriginatorBlockAckAgreement *agreement, const Ptr<const Ieee80211AddbaResponse>& addbaResp);
+    virtual void createAgreement(const Ptr<const Ieee80211AddbaRequest>& addbaRequest, IOriginatorBlockAckAgreementPolicy *blockAckAgreementPolicy);
+    virtual void updateAgreement(OriginatorBlockAckAgreement *agreement, const Ptr<const Ieee80211AddbaResponse>& addbaResp, IOriginatorBlockAckAgreementPolicy *blockAckAgreementPolicy);
     virtual void terminateAgreement(MacAddress originatorAddr, Tid tid);
     virtual const Ptr<Ieee80211Delba> buildDelba(MacAddress receiverAddr, Tid tid, int reasonCode);
     virtual simtime_t computeEarliestExpirationTime();
@@ -48,4 +48,3 @@ class INET_API OriginatorBlockAckAgreementHandler : public IOriginatorBlockAckAg
 } // namespace inet
 
 #endif
-

src/inet/linklayer/ieee80211/mac/blockack/OriginatorBlockAckAgreementPolicy.cc

@@ -24,6 +24,9 @@ void OriginatorBlockAckAgreementPolicy::initialize(int stage)
         aMsduSupported = par("aMsduSupported");
         maximumAllowedBufferSize = par("maximumAllowedBufferSize");
         blockAckTimeoutValue = par("blockAckTimeoutValue");
+        localCompressedBlockAckSupported = par("localCompressedBlockAckSupported");
+        for (const auto& address : cStringTokenizer(par("compressedBlockAckPeerAddresses")).asVector())
+            compressedBlockAckPeerAddresses.insert(MacAddress(address.c_str()));
         // TODO addbaFailureTimeout = par("addbaFailureTimeout");
         WATCH(blockAckReqThreshold);
     }
@@ -53,4 +56,3 @@ bool OriginatorBlockAckAgreementPolicy::isDelbaAccepted(const Ptr<const Ieee8021
 
 } /* namespace ieee80211 */
 } /* namespace inet */
-

src/inet/linklayer/ieee80211/mac/blockack/OriginatorBlockAckAgreementPolicy.h

@@ -26,6 +26,8 @@ class INET_API OriginatorBlockAckAgreementPolicy : public ModeSetListener, publi
     int maximumAllowedBufferSize = -1;
     simtime_t blockAckTimeoutValue = -1;
     simtime_t addbaFailureTimeout = -1;
+    bool localCompressedBlockAckSupported = false;
+    std::set<MacAddress> compressedBlockAckPeerAddresses;
 
   protected:
     virtual int numInitStages() const override { return NUM_INIT_STAGES; }
@@ -41,11 +43,11 @@ class INET_API OriginatorBlockAckAgreementPolicy : public ModeSetListener, publi
     virtual bool isMsduSupported() const override { return aMsduSupported; }
     virtual simtime_t getBlockAckTimeoutValue() const override { return blockAckTimeoutValue; }
     virtual bool isDelayedAckPolicySupported() const override { return delayedAckPolicySupported; }
+    virtual bool isPeerCompressedBlockAckSupported(const MacAddress& peerAddress) const override { return localCompressedBlockAckSupported && compressedBlockAckPeerAddresses.find(peerAddress) != compressedBlockAckPeerAddresses.end(); }
     virtual int getMaximumAllowedBufferSize() const override { return maximumAllowedBufferSize; }
 };
 
 } /* namespace ieee80211 */
 } /* namespace inet */
 
 #endif
-

src/inet/linklayer/ieee80211/mac/blockack/OriginatorBlockAckAgreementPolicy.ned

@@ -23,6 +23,9 @@ simple OriginatorBlockAckAgreementPolicy extends SimpleModule like IOriginatorBl
         bool aMsduSupported = default(true);
         int maximumAllowedBufferSize = default(64);
         double blockAckTimeoutValue @unit(s) = default(0s); // 0 means that it depends on the originator
+        // Interim local HT Compressed Block Ack capability assumption until HT Capabilities IE state is modeled.
+        bool localCompressedBlockAckSupported = default(false);
+        // Explicit peers whose capability state permits HT Compressed Block Ack; empty keeps legacy Basic Block Ack behavior.
+        string compressedBlockAckPeerAddresses = default("");
         @display("i=block/control");
 }
-

src/inet/linklayer/ieee80211/mac/blockack/RecipientBlockAckAgreement.cc

@@ -13,25 +13,23 @@ namespace inet {
 namespace ieee80211 {
 
 RecipientBlockAckAgreement::RecipientBlockAckAgreement(MacAddress originatorAddress, Tid tid, SequenceNumberCyclic startingSequenceNumber, int bufferSize, simtime_t lastUsedTime) :
-    startingSequenceNumber(startingSequenceNumber),
     bufferSize(bufferSize),
     blockAckTimeoutValue(lastUsedTime)
 {
     calculateExpirationTime();
     blockAckRecord = new BlockAckRecord(originatorAddress, tid, startingSequenceNumber);
 }
 
-void RecipientBlockAckAgreement::blockAckPolicyFrameReceived(const Ptr<const Ieee80211DataHeader>& header)
+void RecipientBlockAckAgreement::dataFrameReceived(const Ptr<const Ieee80211DataHeader>& header)
 {
-    ASSERT(header->getAckPolicy() == BLOCK_ACK);
-    blockAckRecord->blockAckPolicyFrameReceived(header);
+    blockAckRecord->dataFrameReceived(header, bufferSize);
 }
 
 std::ostream& operator<<(std::ostream& os, const RecipientBlockAckAgreement& agreement)
 {
     os << "originator address = " << agreement.blockAckRecord->getOriginatorAddress() << ", "
        << "tid = " << agreement.blockAckRecord->getTid() << ", "
-       << "starting sequence number = " << agreement.startingSequenceNumber << ", "
+       << "starting sequence number = " << agreement.getStartingSequenceNumber() << ", "
        << "buffer size = " << agreement.bufferSize << ", "
        << "block ack timeout value = " << agreement.blockAckTimeoutValue;
     return os;

src/inet/linklayer/ieee80211/mac/blockack/RecipientBlockAckAgreement.h

@@ -18,7 +18,6 @@ class INET_API RecipientBlockAckAgreement : public cObject
   protected:
     BlockAckRecord *blockAckRecord = nullptr;
 
-    SequenceNumberCyclic startingSequenceNumber;
     int bufferSize = -1;
     simtime_t blockAckTimeoutValue = 0;
     bool isAddbaResponseSent = false;
@@ -29,12 +28,12 @@ class INET_API RecipientBlockAckAgreement : public cObject
     RecipientBlockAckAgreement(MacAddress originatorAddress, Tid tid, SequenceNumberCyclic startingSequenceNumber, int bufferSize, simtime_t blockAckTimeoutValue);
     virtual ~RecipientBlockAckAgreement() { delete blockAckRecord; }
 
-    virtual void blockAckPolicyFrameReceived(const Ptr<const Ieee80211DataHeader>& header);
+    virtual void dataFrameReceived(const Ptr<const Ieee80211DataHeader>& header);
 
     virtual BlockAckRecord *getBlockAckRecord() const { return blockAckRecord; }
     virtual simtime_t getBlockAckTimeoutValue() const { return blockAckTimeoutValue; }
     virtual int getBufferSize() const { return bufferSize; }
-    virtual SequenceNumberCyclic getStartingSequenceNumber() const { return startingSequenceNumber; }
+    virtual SequenceNumberCyclic getStartingSequenceNumber() const { return blockAckRecord->getStartingSequenceNumber(); }
     virtual bool getIsAddbaResponseSent() const { return isAddbaResponseSent; }
     virtual bool getIsDelayedBlockAckPolicySupported() const { return isDelayedBlockAckPolicySupported; }