diff --git a/core/java/android/net/ConnectivityDiagnosticsManager.java b/core/java/android/net/ConnectivityDiagnosticsManager.java
index b128ea7..3c39d15 100644
--- a/core/java/android/net/ConnectivityDiagnosticsManager.java
+++ b/core/java/android/net/ConnectivityDiagnosticsManager.java
@@ -202,7 +202,7 @@
          */
         @NetworkProbe
         public static final String KEY_NETWORK_PROBES_ATTEMPTED_BITMASK =
-                "networkProbesAttemped";
+                "networkProbesAttempted";
 
         /** @hide */
         @StringDef(prefix = {"KEY_"}, value = {
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index bdd2007..b3b1722 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -68,6 +68,7 @@
 import android.net.CaptivePortal;
 import android.net.ConnectionInfo;
 import android.net.ConnectivityDiagnosticsManager.ConnectivityReport;
+import android.net.ConnectivityDiagnosticsManager.DataStallReport;
 import android.net.ConnectivityManager;
 import android.net.ICaptivePortal;
 import android.net.IConnectivityDiagnosticsCallback;
@@ -3009,6 +3010,21 @@
         }
 
         @Override
+        public void notifyDataStallSuspected(
+                long timestampMillis, int detectionMethod, PersistableBundle extras) {
+            final Message msg =
+                    mConnectivityDiagnosticsHandler.obtainMessage(
+                            ConnectivityDiagnosticsHandler.EVENT_DATA_STALL_SUSPECTED,
+                            detectionMethod, mNetId, timestampMillis);
+            msg.setData(new Bundle(extras));
+
+            // NetworkStateTrackerHandler currently doesn't take any actions based on data
+            // stalls so send the message directly to ConnectivityDiagnosticsHandler and avoid
+            // the cost of going through two handlers.
+            mConnectivityDiagnosticsHandler.sendMessage(msg);
+        }
+
+        @Override
         public int getInterfaceVersion() {
             return this.VERSION;
         }
@@ -4194,6 +4210,19 @@
         final int connectivityInfo = encodeBool(hasConnectivity);
         mHandler.sendMessage(
                 mHandler.obtainMessage(EVENT_REVALIDATE_NETWORK, uid, connectivityInfo, network));
+
+        final NetworkAgentInfo nai;
+        if (network == null) {
+            nai = getDefaultNetwork();
+        } else {
+            nai = getNetworkAgentInfoForNetwork(network);
+        }
+        if (nai != null) {
+            mConnectivityDiagnosticsHandler.sendMessage(
+                    mConnectivityDiagnosticsHandler.obtainMessage(
+                            ConnectivityDiagnosticsHandler.EVENT_NETWORK_CONNECTIVITY_REPORTED,
+                            connectivityInfo, 0, nai));
+        }
     }
 
     private void handleReportNetworkConnectivity(
@@ -7562,6 +7591,8 @@
      */
     @VisibleForTesting
     class ConnectivityDiagnosticsHandler extends Handler {
+        private final String mTag = ConnectivityDiagnosticsHandler.class.getSimpleName();
+
         /**
          * Used to handle ConnectivityDiagnosticsCallback registration events from {@link
          * android.net.ConnectivityDiagnosticsManager}.
@@ -7589,6 +7620,26 @@
          */
         private static final int EVENT_NETWORK_TESTED = ConnectivityService.EVENT_NETWORK_TESTED;
 
+        /**
+         * Event for NetworkMonitor to inform ConnectivityService that a potential data stall has
+         * been detected on the network.
+         * obj = Long the timestamp (in millis) for when the suspected data stall was detected.
+         * arg1 = {@link DataStallReport#DetectionMethod} indicating the detection method.
+         * arg2 = NetID.
+         * data = PersistableBundle of extras passed from NetworkMonitor.
+         */
+        private static final int EVENT_DATA_STALL_SUSPECTED = 4;
+
+        /**
+         * Event for ConnectivityDiagnosticsHandler to handle network connectivity being reported to
+         * the platform. This event will invoke {@link
+         * IConnectivityDiagnosticsCallback#onNetworkConnectivityReported} for permissioned
+         * callbacks.
+         * obj = Network that was reported on
+         * arg1 = boolint for the quality reported
+         */
+        private static final int EVENT_NETWORK_CONNECTIVITY_REPORTED = 5;
+
         private ConnectivityDiagnosticsHandler(Looper looper) {
             super(looper);
         }
@@ -7619,6 +7670,24 @@
                     handleNetworkTestedWithExtras(reportEvent, extras);
                     break;
                 }
+                case EVENT_DATA_STALL_SUSPECTED: {
+                    final NetworkAgentInfo nai = getNetworkAgentInfoForNetId(msg.arg2);
+                    if (nai == null) break;
+
+                    // This is safe because NetworkMonitorCallbacks#notifyDataStallSuspected
+                    // receives a PersistableBundle and converts it to the Bundle in the incoming
+                    // Message.
+                    final PersistableBundle extras = new PersistableBundle(msg.getData());
+                    handleDataStallSuspected(nai, (long) msg.obj, msg.arg1, extras);
+                    break;
+                }
+                case EVENT_NETWORK_CONNECTIVITY_REPORTED: {
+                    handleNetworkConnectivityReported((NetworkAgentInfo) msg.obj, toBool(msg.arg1));
+                    break;
+                }
+                default: {
+                    Log.e(mTag, "Unrecognized event in ConnectivityDiagnostics: " + msg.what);
+                }
             }
         }
     }
@@ -7748,6 +7817,35 @@
         }
     }
 
+    private void handleDataStallSuspected(
+            @NonNull NetworkAgentInfo nai, long timestampMillis, int detectionMethod,
+            @NonNull PersistableBundle extras) {
+        final DataStallReport report =
+                new DataStallReport(nai.network, timestampMillis, detectionMethod, extras);
+        final List<IConnectivityDiagnosticsCallback> results =
+                getMatchingPermissionedCallbacks(nai);
+        for (final IConnectivityDiagnosticsCallback cb : results) {
+            try {
+                cb.onDataStallSuspected(report);
+            } catch (RemoteException ex) {
+                loge("Error invoking onDataStallSuspected", ex);
+            }
+        }
+    }
+
+    private void handleNetworkConnectivityReported(
+            @NonNull NetworkAgentInfo nai, boolean connectivity) {
+        final List<IConnectivityDiagnosticsCallback> results =
+                getMatchingPermissionedCallbacks(nai);
+        for (final IConnectivityDiagnosticsCallback cb : results) {
+            try {
+                cb.onNetworkConnectivityReported(nai.network, connectivity);
+            } catch (RemoteException ex) {
+                loge("Error invoking onNetworkConnectivityReported", ex);
+            }
+        }
+    }
+
     private List<IConnectivityDiagnosticsCallback> getMatchingPermissionedCallbacks(
             @NonNull NetworkAgentInfo nai) {
         final List<IConnectivityDiagnosticsCallback> results = new ArrayList<>();
diff --git a/tests/net/java/com/android/server/ConnectivityServiceTest.java b/tests/net/java/com/android/server/ConnectivityServiceTest.java
index 8162843..8da1a5b 100644
--- a/tests/net/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/net/java/com/android/server/ConnectivityServiceTest.java
@@ -24,6 +24,7 @@
 import static android.content.pm.PackageManager.PERMISSION_DENIED;
 import static android.content.pm.PackageManager.PERMISSION_GRANTED;
 import static android.net.ConnectivityDiagnosticsManager.ConnectivityReport;
+import static android.net.ConnectivityDiagnosticsManager.DataStallReport;
 import static android.net.ConnectivityManager.ACTION_CAPTIVE_PORTAL_SIGN_IN;
 import static android.net.ConnectivityManager.CONNECTIVITY_ACTION;
 import static android.net.ConnectivityManager.CONNECTIVITY_ACTION_SUPL;
@@ -570,6 +571,9 @@
                 | NETWORK_VALIDATION_RESULT_PARTIAL;
         private static final int VALIDATION_RESULT_INVALID = 0;
 
+        private static final long DATA_STALL_TIMESTAMP = 10L;
+        private static final int DATA_STALL_DETECTION_METHOD = 1;
+
         private INetworkMonitor mNetworkMonitor;
         private INetworkMonitorCallbacks mNmCallbacks;
         private int mNmValidationResult = VALIDATION_RESULT_BASE;
@@ -577,6 +581,7 @@
         private int mProbesSucceeded;
         private String mNmValidationRedirectUrl = null;
         private PersistableBundle mValidationExtras = PersistableBundle.EMPTY;
+        private PersistableBundle mDataStallExtras = PersistableBundle.EMPTY;
         private boolean mNmProvNotificationRequested = false;
 
         private final ConditionVariable mNetworkStatusReceived = new ConditionVariable();
@@ -804,6 +809,11 @@
         public void expectPreventReconnectReceived() {
             expectPreventReconnectReceived(TIMEOUT_MS);
         }
+
+        void notifyDataStallSuspected() throws Exception {
+            mNmCallbacks.notifyDataStallSuspected(
+                    DATA_STALL_TIMESTAMP, DATA_STALL_DETECTION_METHOD, mDataStallExtras);
+        }
     }
 
     /**
@@ -6436,14 +6446,16 @@
     public void testRegisterUnregisterConnectivityDiagnosticsCallback() throws Exception {
         final NetworkRequest wifiRequest =
                 new NetworkRequest.Builder().addTransportType(TRANSPORT_WIFI).build();
-
         when(mConnectivityDiagnosticsCallback.asBinder()).thenReturn(mIBinder);
 
         mService.registerConnectivityDiagnosticsCallback(
                 mConnectivityDiagnosticsCallback, wifiRequest, mContext.getPackageName());
 
-        verify(mIBinder, timeout(TIMEOUT_MS))
-                .linkToDeath(any(ConnectivityDiagnosticsCallbackInfo.class), anyInt());
+        // Block until all other events are done processing.
+        HandlerUtilsKt.waitForIdle(mCsHandlerThread, TIMEOUT_MS);
+
+        verify(mIBinder).linkToDeath(any(ConnectivityDiagnosticsCallbackInfo.class), anyInt());
+        verify(mConnectivityDiagnosticsCallback).asBinder();
         assertTrue(
                 mService.mConnectivityDiagnosticsCallbacks.containsKey(
                         mConnectivityDiagnosticsCallback));
@@ -6466,8 +6478,10 @@
         mService.registerConnectivityDiagnosticsCallback(
                 mConnectivityDiagnosticsCallback, wifiRequest, mContext.getPackageName());
 
-        verify(mIBinder, timeout(TIMEOUT_MS))
-                .linkToDeath(any(ConnectivityDiagnosticsCallbackInfo.class), anyInt());
+        // Block until all other events are done processing.
+        HandlerUtilsKt.waitForIdle(mCsHandlerThread, TIMEOUT_MS);
+
+        verify(mIBinder).linkToDeath(any(ConnectivityDiagnosticsCallbackInfo.class), anyInt());
         verify(mConnectivityDiagnosticsCallback).asBinder();
         assertTrue(
                 mService.mConnectivityDiagnosticsCallbacks.containsKey(
@@ -6599,8 +6613,7 @@
         mServiceContext.setPermission(perm, PERMISSION_GRANTED);
     }
 
-    @Test
-    public void testConnectivityDiagnosticsCallbackOnConnectivityReport() throws Exception {
+    private void setUpConnectivityDiagnosticsCallback() throws Exception {
         final NetworkRequest request = new NetworkRequest.Builder().build();
         when(mConnectivityDiagnosticsCallback.asBinder()).thenReturn(mIBinder);
 
@@ -6620,9 +6633,58 @@
         mCellNetworkAgent.connect(true);
         callback.expectAvailableThenValidatedCallbacks(mCellNetworkAgent);
         callback.assertNoCallback();
+    }
 
-        // Wait for onConnectivityReport to fire
-        verify(mConnectivityDiagnosticsCallback, timeout(TIMEOUT_MS))
+    @Test
+    public void testConnectivityDiagnosticsCallbackOnConnectivityReport() throws Exception {
+        setUpConnectivityDiagnosticsCallback();
+
+        // Block until all other events are done processing.
+        HandlerUtilsKt.waitForIdle(mCsHandlerThread, TIMEOUT_MS);
+
+        // Verify onConnectivityReport fired
+        verify(mConnectivityDiagnosticsCallback)
                 .onConnectivityReport(any(ConnectivityReport.class));
     }
+
+    @Test
+    public void testConnectivityDiagnosticsCallbackOnDataStallSuspected() throws Exception {
+        setUpConnectivityDiagnosticsCallback();
+
+        // Trigger notifyDataStallSuspected() on the INetworkMonitorCallbacks instance in the
+        // cellular network agent
+        mCellNetworkAgent.notifyDataStallSuspected();
+
+        // Block until all other events are done processing.
+        HandlerUtilsKt.waitForIdle(mCsHandlerThread, TIMEOUT_MS);
+
+        // Verify onDataStallSuspected fired
+        verify(mConnectivityDiagnosticsCallback).onDataStallSuspected(any(DataStallReport.class));
+    }
+
+    @Test
+    public void testConnectivityDiagnosticsCallbackOnConnectivityReported() throws Exception {
+        setUpConnectivityDiagnosticsCallback();
+
+        final Network n = mCellNetworkAgent.getNetwork();
+        final boolean hasConnectivity = true;
+        mService.reportNetworkConnectivity(n, hasConnectivity);
+
+        // Block until all other events are done processing.
+        HandlerUtilsKt.waitForIdle(mCsHandlerThread, TIMEOUT_MS);
+
+        // Verify onNetworkConnectivityReported fired
+        verify(mConnectivityDiagnosticsCallback)
+                .onNetworkConnectivityReported(eq(n), eq(hasConnectivity));
+
+        final boolean noConnectivity = false;
+        mService.reportNetworkConnectivity(n, noConnectivity);
+
+        // Block until all other events are done processing.
+        HandlerUtilsKt.waitForIdle(mCsHandlerThread, TIMEOUT_MS);
+
+        // Wait for onNetworkConnectivityReported to fire
+        verify(mConnectivityDiagnosticsCallback)
+                .onNetworkConnectivityReported(eq(n), eq(noConnectivity));
+    }
 }