SDAP: QfiContextManager: clean up, rename to DrbTable

- QfiContextManager API cleanup
- DrbContext::drbIndex -> drbId (DrbId), remove lcid field
- Restructure QfiContextManager with DrbKey primary map, (nodeId,qfi)
  reverse map, isDefault flag + default DRB accelerators
- Rename DrbContext -> DrbConfig
- Rename QfiContextManager -> DrbTable, QfiContext.h -> DrbConfig.h

Author: avarga

src/simu5g/stack/mac/scheduling_modules/QoSAwareScheduler.h

@@ -22,15 +22,15 @@ namespace simu5g {
 
 /**
  * Extends the LTE/NR MAC layer scheduler to support QoS-aware scheduling
- * decisions based on QFI (QoS Flow Identifier) contexts. QfiContextManager
+ * decisions based on QFI (QoS Flow Identifier) contexts. DrbTable
  * maintains mappings between QFIs, CIDs, and their associated QoS parameters.
  *
  * Key Features:
  * - Implements a PF-based scheduler that dynamically scores active CIDs using
  *   QoS weights derived from QFI context (e.g., 5QI, GBR, delay budget, PER,
  *   priority).
  * - Supports per-CID registration of QFIs
- * - QfiContextManager can load QFI-DRB configurations from file
+ * - DrbTable can load QFI-DRB configurations from file
  * - Provides flexible QoS weight computation based on service criticality.
  * - Enables more realistic traffic differentiation for scenarios involving
  *   conversational voice, URLLC, video streaming, etc.

src/simu5g/stack/sdap/NrSdap.cc

@@ -33,10 +33,10 @@ void NrSdap::initialize()
     // Load QFI-to-DRB mapping from drbConfig parameter
     const cValueArray *arr = check_and_cast_nullable<const cValueArray *>(par("drbConfig").objectValue());
     if (arr && arr->size() > 0) {
-        qfiContextManager_.loadFromJson(arr);
-        EV << "NrSdap: Loaded " << qfiContextManager_.getDrbMap().size() << " DRB entries from drbConfig" << endl;
-        for (const auto& [drb, ctx] : qfiContextManager_.getDrbMap())
-            EV << "  DRB " << drb << ": " << ctx << endl;
+        drbTable_.loadFromJson(arr);
+        EV << "NrSdap: Loaded " << drbTable_.getDrbMap().size() << " DRB entries from drbConfig" << endl;
+        for (const auto& [key, ctx] : drbTable_.getDrbMap())
+            EV << "  " << key << ": " << ctx << endl;
     }
 
     // Get pointer to reflective QoS table
@@ -49,7 +49,7 @@ void NrSdap::initialize()
         throw cRuntimeError("Only UE may use a reflective QoS table");
 }
 
-bool NrSdap::requiresSdapHeader(int drbIndex)
+bool NrSdap::requiresSdapHeader(const DrbConfig *drb)
 {
     return par("addSdapHeader").boolValue(); // for now -- should come from RRC config
 }
@@ -59,7 +59,7 @@ bool NrSdap::shouldEnableReflectiveQos(int qfi)
     return par("useReflectiveQos").boolValue(); // for now -- should come from RRC config
 }
 
-const inet::Protocol *NrSdap::getUpperProtocol(const DrbContext *ctx)
+const inet::Protocol *NrSdap::getUpperProtocol(const DrbConfig *ctx)
 {
     // If an explicit upperProtocol is configured on this DRB, use it
     if (ctx && !ctx->upperProtocol.empty()) {
@@ -138,44 +138,28 @@ void NrSdap::handleUpperPacket(inet::Packet *pkt)
         EV_WARN << "SDAP TX: QfiReq not found on gNB path, defaulting QFI to 0\n";
     }
 
-    // Lookup DRB index
-    int drbIndex = 0;
-
-    if (isUe) {
-        // UE side: simple QFI -> drbIndex lookup
-        int idx = qfiContextManager_.getDrbIndexForQfi(qfi);
-        if (idx >= 0)
-            drbIndex = idx;
-        else
-            EV_WARN << "SDAP TX: No DRB mapping for QFI=" << (int)qfi << " on UE, using DRB 0\n";
-    } else {
-        // gNB side: need dest UE nodeId + QFI -> drbIndex
-        MacNodeId destUeId = pkt->getTag<FlowControlInfo>()->getDestId();
-        if (destUeId == NODEID_NONE)
-            EV_WARN << "SDAP TX: destId not set in FlowControlInfo, using DRB 0\n";
-        else {
-            int idx = qfiContextManager_.getDrbIndex(destUeId, qfi);
-            if (idx >= 0)
-                drbIndex = idx;
-            else {
-                // Fallback: use first DRB configured for this UE
-                int fallback = qfiContextManager_.getFirstDrbForUe(destUeId);
-                if (fallback >= 0) {
-                    drbIndex = fallback;
-                    EV_WARN << "SDAP TX: No DRB mapping for ueNodeId=" << destUeId << " QFI=" << (int)qfi
-                            << ", falling back to first DRB " << drbIndex << " for this UE\n";
-                } else {
-                    EV_WARN << "SDAP TX: No DRB mapping for ueNodeId=" << destUeId << " QFI=" << (int)qfi
-                            << ", no DRBs configured for this UE, using DRB 0\n";
-                }
-            }
-        }
+    // Lookup DRB context: nodeId is NODEID_NONE on UE, destUeId on gNB
+    MacNodeId nodeId = NODEID_NONE;
+    if (!isUe) {
+        nodeId = pkt->getTag<FlowControlInfo>()->getDestId();
+        if (nodeId == NODEID_NONE)
+            EV_WARN << "SDAP TX: destId not set in FlowControlInfo\n";
+    }
+
+    const DrbConfig *drb = drbTable_.getDrbForQfi(nodeId, qfi);
+    if (!drb) {
+        drb = drbTable_.getDefaultDrb(nodeId);
+        if (drb)
+            EV_WARN << "SDAP TX: No DRB mapping for nodeId=" << nodeId << " QFI=" << (int)qfi
+                    << ", falling back to default DRB " << drb->drbId << "\n";
     }
+    if (!drb)
+        throw cRuntimeError("SDAP TX: No DRB available for nodeId=%d", (int)num(nodeId));
 
-    EV_INFO << "SDAP TX: Selected DRB=" << drbIndex << " for QFI=" << (int)qfi << "\n";
+    EV_INFO << "SDAP TX: Selected DRB=" << drb->drbId << " for QFI=" << (int)qfi << "\n";
 
     // Check if SDAP header is required for this DRB
-    if (requiresSdapHeader(drbIndex)) {
+    if (requiresSdapHeader(drb)) {
         // Build SDAP header according to 3GPP TS 37.324
         auto sdapHeader = makeShared<NrSdapHeader>();
         sdapHeader->setQfi(qfi);
@@ -189,38 +173,38 @@ void NrSdap::handleUpperPacket(inet::Packet *pkt)
                 << ", reflectiveQoS = " << (enableReflectiveQos ? "true" : "false") << "\n";
     }
     else {
-        EV_INFO << "SDAP TX: No SDAP header required for DRB " << drbIndex << "\n";
+        EV_INFO << "SDAP TX: No SDAP header required for DRB " << drb->drbId << "\n";
     }
 
     // Set DRB ID and RLC type on FlowControlInfo for PDCP/RLC entity creation and routing
     auto lteInfo = pkt->getTagForUpdate<FlowControlInfo>();
-    lteInfo->setDrbId(DrbId(drbIndex));
-    const DrbContext *ctx = qfiContextManager_.getDrbContext(drbIndex);
-    if (ctx)
-        lteInfo->setRlcType(ctx->rlcType);
+    lteInfo->setDrbId(drb->drbId);
+    lteInfo->setRlcType(drb->rlcType);
 
     // Establish connection if not yet done for this (drbId, destId) pair
-    if (establishedConnections_.insert({DrbId(drbIndex), lteInfo->getDestId()}).second)
+    if (establishedConnections_.insert({drb->drbId, lteInfo->getDestId()}).second)
         binder_->establishUnidirectionalDataConnection(lteInfo.get());
 
     // Set protocol tag for outgoing frame to PDCP layer
     pkt->addTagIfAbsent<PacketProtocolTag>()->setProtocol(&LteProtocol::sdap);
 
-    EV_INFO << "SDAP TX: Forwarding to DRB " << drbIndex << "\n";
+    EV_INFO << "SDAP TX: Forwarding to DRB " << drb->drbId << "\n";
     send(pkt, "pdcpOut");
 }
 
 void NrSdap::handleLowerPacket(inet::Packet *pkt)
 {
     auto lteInfo = pkt->findTag<FlowControlInfo>();
-    int drbIndex = lteInfo ? num(lteInfo->getDrbId()) : -1;
+    DrbId drbId = lteInfo ? lteInfo->getDrbId() : DRBID_NONE;
+    MacNodeId ueId = (!isUe && lteInfo) ? lteInfo->getSourceId() : NODEID_NONE;
+    const DrbConfig *drb = (drbId != DRBID_NONE) ? drbTable_.getDrb(DrbKey(ueId, drbId)) : nullptr;
 
-    EV_INFO << "SDAP RX: Received packet from DRB " << drbIndex << ": " << pkt->peekAtFront() << "\n";
+    EV_INFO << "SDAP RX: Received packet from DRB " << drbId << ": " << pkt->peekAtFront() << "\n";
 
     int qfi = 0;
 
     // Check if packet has SDAP header (should be at the front according to 3GPP TS 37.324)
-    if (requiresSdapHeader(drbIndex)) {
+    if (requiresSdapHeader(drb)) {
         // Extract SDAP header from the front of the packet
         auto sdapHeader = pkt->removeAtFront<NrSdapHeader>();
         qfi = sdapHeader->getQfi();
@@ -242,30 +226,27 @@ void NrSdap::handleLowerPacket(inet::Packet *pkt)
         }
     }
     else {
-        EV_INFO << "SDAP RX: No SDAP header expected for DRB " << drbIndex << "\n";
+        EV_INFO << "SDAP RX: No SDAP header expected for DRB " << drbId << "\n";
 
         // For DRBs without SDAP header, derive QFI from DRB context (use first QFI in the list)
-        const DrbContext* ctx = qfiContextManager_.getDrbContext(drbIndex);
-        if (ctx && !ctx->qfiList.empty()) {
-            qfi = ctx->qfiList[0];
+        if (drb && !drb->qfiList.empty()) {
+            qfi = drb->qfiList[0];
             EV_INFO << "SDAP RX: Using QFI " << qfi << " from DRB context\n";
         }
     }
 
     // Validate QFI ↔ DRB consistency
-    const DrbContext* ctxValidate = qfiContextManager_.getDrbContext(drbIndex);
-    if (ctxValidate) {
-        if (!contains(ctxValidate->qfiList, (int)qfi))
-            EV_WARN << "SDAP RX: DRB/QFI mismatch! Received on DRB=" << drbIndex << ", QFI=" << qfi << " not in qfiList\n";
+    if (drb) {
+        if (!contains(drb->qfiList, (int)qfi))
+            EV_WARN << "SDAP RX: DRB/QFI mismatch! Received on DRB=" << drbId << ", QFI=" << qfi << " not in qfiList\n";
     }
 
     // Add QoS indication tag for upper layers
     auto qosIndTag = pkt->addTagIfAbsent<QfiInd>();
     qosIndTag->setQfi(qfi);
 
     // Set protocol tag for upper layer based on PDU session type
-    const DrbContext* ctxProto = qfiContextManager_.getDrbContext(drbIndex);
-    const inet::Protocol *upperProto = getUpperProtocol(ctxProto);
+    const inet::Protocol *upperProto = getUpperProtocol(drb);
     pkt->addTagIfAbsent<PacketProtocolTag>()->setProtocol(upperProto);
 
     EV_INFO << "SDAP RX: Forwarding packet with QFI " << qfi << " to upper layer (protocol: " << upperProto->getName() << ")\n";

src/simu5g/stack/sdap/NrSdap.h

@@ -14,7 +14,7 @@
 
 #include <omnetpp.h>
 #include <set>
-#include "simu5g/stack/sdap/common/QfiContextManager.h"
+#include "simu5g/stack/sdap/common/DrbTable.h"
 #include "simu5g/stack/sdap/common/ReflectiveQosTable.h"
 #include "simu5g/common/binder/Binder.h"
 #include <inet/common/ModuleRefByPar.h>
@@ -44,7 +44,7 @@ namespace simu5g {
 class NrSdap : public cSimpleModule
 {
   protected:
-    QfiContextManager qfiContextManager_;
+    DrbTable drbTable_;
     inet::ModuleRefByPar<ReflectiveQosTable> reflectiveQosTable;
     inet::ModuleRefByPar<Binder> binder_;
     bool isUe = true;  // Node role: true for UE, false for gNB
@@ -53,17 +53,14 @@ class NrSdap : public cSimpleModule
     std::set<std::pair<DrbId, MacNodeId>> establishedConnections_;
 
   protected:
-    bool requiresSdapHeader(int drbIndex);
+    bool requiresSdapHeader(const DrbConfig *drb);
     bool shouldEnableReflectiveQos(int qfi);
-    const inet::Protocol *getUpperProtocol(const DrbContext *ctx);
+    const inet::Protocol *getUpperProtocol(const DrbConfig *ctx);
     virtual void initialize() override;
     virtual void handleMessage(cMessage *msg) override;
     virtual void handleUpperPacket(inet::Packet *pkt);
     virtual void handleLowerPacket(inet::Packet *pkt);
 
-  public:
-    int getLcid(int drbIndex) { return qfiContextManager_.getLcid(drbIndex); }
-    int getDrbIndexForMacCid(MacNodeId ueNodeId, LogicalCid lcid) { return qfiContextManager_.getDrbIndexForMacCid(ueNodeId, lcid); }
 };
 
 } //namespace

src/simu5g/stack/sdap/NrSdap.ned

@@ -25,6 +25,20 @@ package simu5g.stack.sdap;
 // Supports all 3GPP PDU session types (IPv4, IPv6, Ethernet, Unstructured)
 // via the pduSessionType field in drbConfig.
 //
+// drbConfig fields:
+//  - drb (int): DRB identifier (= nrPdcp[]/nrRlc[] array index)
+//  - ue (int, optional): UE MacNodeId (gNB only; omit on UE side)
+//  - qfiList (int[]): QFI values mapped to this DRB
+//  - rlcType (string, optional): RLC mode ("AM", "UM", "TM"); default: "UM"
+//  - pduSessionType (string, optional): "IPv4", "IPv6", "Ethernet", "Unstructured";
+//    default: "IPv4"
+//  - upperProtocol (string, optional): INET protocol name for upper layer dispatch
+//    (this is normally only needed for "Unstructured" PDU sessions); default:
+//    derived from pduSessionType
+//  - isDefault (bool, optional): marks this as the default DRB for the UE;
+//    if omitted, the first DRB entry per UE (per nodeId) is automatically used
+//    as default. The default DRB is the fallback when no QFI-to-DRB mapping matches.
+//
 // Gates:
 //  - upperLayerIn/upperLayerOut: connects to the upper layer (Ip2Nic or app).
 //  - pdcpIn/pdcpOut: connects to the PDCP layer.
@@ -34,7 +48,7 @@ simple NrSdap like INrSdap
     parameters:
         string nodeRole @enum("UE", "gNB");  // Node role: "UE" or "gNB" - determines reflective QoS behavior
         string binderModule = default("binder");
-        object drbConfig = default([]);  // JSON array of DRB configurations: [{drb, ue, qfiList, rlcType, pduSessionType, upperProtocol}, ...]; rlcType defaults to UM, pduSessionType defaults to IPv4, upperProtocol defaults based on pduSessionType.
+        object drbConfig = default([]);  // JSON array: [{drb, ue, qfiList, rlcType, pduSessionType, upperProtocol, isDefault}, ...]; see banner comment for details
         string reflectiveQosTableModule = default("");  // UE only: path to ReflectiveQosTable module (empty = disabled)
         bool addSdapHeader = default(true);
         bool useReflectiveQos = default(false); // UE only

src/simu5g/stack/sdap/common/QfiContext.h src/simu5g/stack/sdap/common/DrbConfig.hsrc/simu5g/stack/sdap/common/QfiContext.h renamed to src/simu5g/stack/sdap/common/DrbConfig.h

@@ -9,27 +9,29 @@
 // and cannot be removed from it.
 ///
 
-#ifndef STACK_SDAP_COMMON_QFICONTEXT_H_
-#define STACK_SDAP_COMMON_QFICONTEXT_H_
+#ifndef STACK_SDAP_COMMON_DRBCONFIG_H_
+#define STACK_SDAP_COMMON_DRBCONFIG_H_
 
 #include <vector>
 #include "simu5g/common/LteCommon.h"
 
 namespace simu5g {
 
 // Per-DRB configuration entry, built from the drbConfig JSON parameter.
-struct DrbContext {
-    int drbIndex = -1;              // global DRB instance index (= nrPdcp[]/nrRlc[] array index)
+struct DrbConfig {
+    DrbId drbId = DRBID_NONE;         // DRB identifier (= nrPdcp[]/nrRlc[] array index)
     MacNodeId ueNodeId = NODEID_NONE; // NODEID_NONE = "self" (UE side); numeric MacNodeId on gNB
-    int lcid = -1;                  // LCID = local DRB index within that UE's DRB set (auto-derived)
+    bool isDefault = false;           // true if this is the default DRB for this UE
     std::vector<int> qfiList;       // QFIs mapped to this DRB
     LteRlcType rlcType = UM;        // RLC mode for this DRB (AM, UM, TM)
     PduSessionType pduSessionType = IP_V4;  // PDU session type (3GPP TS 23.501)
     std::string upperProtocol;  // INET protocol name for upper layer dispatch (empty = derive from pduSessionType)
 };
 
-inline std::ostream& operator<<(std::ostream& os, const DrbContext& ctx) {
-    os << "ue=" << ctx.ueNodeId << " lcid=" << ctx.lcid << " qfi=[";
+inline std::ostream& operator<<(std::ostream& os, const DrbConfig& ctx) {
+    os << "drbId=" << ctx.drbId << " ue=" << ctx.ueNodeId;
+    if (ctx.isDefault) os << " DEFAULT";
+    os << " qfi=[";
     for (int i = 0; i < (int)ctx.qfiList.size(); i++) {
         if (i) os << ",";
         os << ctx.qfiList[i];
@@ -47,4 +49,4 @@ inline std::ostream& operator<<(std::ostream& os, const std::pair<MacNodeId,int>
 
 } // namespace simu5g
 
-#endif /* STACK_SDAP_COMMON_QFICONTEXT_H_ */
+#endif /* STACK_SDAP_COMMON_DRBCONFIG_H_ */