diff --git a/Tethering/src/com/android/server/connectivity/tethering/Tethering.java b/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
index 490b83f..c84892d 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
@@ -303,7 +303,8 @@
 
         final UserManager userManager = (UserManager) mContext.getSystemService(
                 Context.USER_SERVICE);
-        mTetheringRestriction = new UserRestrictionActionListener(userManager, this);
+        mTetheringRestriction = new UserRestrictionActionListener(
+                userManager, this, mNotificationUpdater);
         mExecutor = new TetheringThreadExecutor(mHandler);
         mActiveDataSubIdListener = new ActiveDataSubIdListener(mExecutor);
 
@@ -432,9 +433,7 @@
         // Called by wifi when the number of soft AP clients changed.
         @Override
         public void onConnectedClientsChanged(final List<WifiClient> clients) {
-            if (mConnectedClientsTracker.updateConnectedClients(mForwardedDownstreams, clients)) {
-                reportTetherClientsChanged(mConnectedClientsTracker.getLastTetheredClients());
-            }
+            updateConnectedClients(clients);
         }
     }
 
@@ -636,7 +635,10 @@
                 Context.ETHERNET_SERVICE);
         synchronized (mPublicSync) {
             if (enable) {
-                if (mEthernetCallback != null) return TETHER_ERROR_NO_ERROR;
+                if (mEthernetCallback != null) {
+                    Log.d(TAG, "Ethernet tethering already started");
+                    return TETHER_ERROR_NO_ERROR;
+                }
 
                 mEthernetCallback = new EthernetCallback();
                 mEthernetIfaceRequest = em.requestTetheredInterface(mExecutor, mEthernetCallback);
@@ -997,11 +999,14 @@
     protected static class UserRestrictionActionListener {
         private final UserManager mUserManager;
         private final Tethering mWrapper;
+        private final TetheringNotificationUpdater mNotificationUpdater;
         public boolean mDisallowTethering;
 
-        public UserRestrictionActionListener(UserManager um, Tethering wrapper) {
+        public UserRestrictionActionListener(@NonNull UserManager um, @NonNull Tethering wrapper,
+                @NonNull TetheringNotificationUpdater updater) {
             mUserManager = um;
             mWrapper = wrapper;
+            mNotificationUpdater = updater;
             mDisallowTethering = false;
         }
 
@@ -1020,13 +1025,21 @@
                 return;
             }
 
-            // TODO: Add user restrictions notification.
-            final boolean isTetheringActiveOnDevice = (mWrapper.getTetheredIfaces().length != 0);
-
-            if (newlyDisallowed && isTetheringActiveOnDevice) {
-                mWrapper.untetherAll();
-                // TODO(b/148139325): send tetheringSupported on restriction change
+            if (!newlyDisallowed) {
+                // Clear the restricted notification when user is allowed to have tethering
+                // function.
+                mNotificationUpdater.tetheringRestrictionLifted();
+                return;
             }
+
+            // Restricted notification is shown when tethering function is disallowed on
+            // user's device.
+            mNotificationUpdater.notifyTetheringDisabledByRestriction();
+
+            // Untether from all downstreams since tethering is disallowed.
+            mWrapper.untetherAll();
+
+            // TODO(b/148139325): send tetheringSupported on restriction change
         }
     }
 
@@ -1560,6 +1573,7 @@
             mIPv6TetheringCoordinator.removeActiveDownstream(who);
             mOffload.excludeDownstreamInterface(who.interfaceName());
             mForwardedDownstreams.remove(who);
+            updateConnectedClients(null /* wifiClients */);
 
             // If this is a Wi-Fi interface, tell WifiManager of any errors
             // or the inactive serving state.
@@ -2142,6 +2156,12 @@
         return false;
     }
 
+    private void updateConnectedClients(final List<WifiClient> wifiClients) {
+        if (mConnectedClientsTracker.updateConnectedClients(mForwardedDownstreams, wifiClients)) {
+            reportTetherClientsChanged(mConnectedClientsTracker.getLastTetheredClients());
+        }
+    }
+
     private IpServer.Callback makeControlCallback() {
         return new IpServer.Callback() {
             @Override
@@ -2156,10 +2176,7 @@
 
             @Override
             public void dhcpLeasesChanged() {
-                if (mConnectedClientsTracker.updateConnectedClients(
-                        mForwardedDownstreams, null /* wifiClients */)) {
-                    reportTetherClientsChanged(mConnectedClientsTracker.getLastTetheredClients());
-                }
+                updateConnectedClients(null /* wifiClients */);
             }
         };
     }
diff --git a/Tethering/src/com/android/server/connectivity/tethering/TetheringNotificationUpdater.java b/Tethering/src/com/android/server/connectivity/tethering/TetheringNotificationUpdater.java
index b3fff44..992cdd8 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/TetheringNotificationUpdater.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/TetheringNotificationUpdater.java
@@ -36,6 +36,7 @@
 
 import androidx.annotation.ArrayRes;
 import androidx.annotation.DrawableRes;
+import androidx.annotation.IntDef;
 import androidx.annotation.IntRange;
 import androidx.annotation.NonNull;
 
@@ -61,7 +62,9 @@
     private static final boolean NOTIFY_DONE = true;
     private static final boolean NO_NOTIFY = false;
     // Id to update and cancel tethering notification. Must be unique within the tethering app.
-    private static final int NOTIFY_ID = 20191115;
+    private static final int ENABLE_NOTIFICATION_ID = 1000;
+    // Id to update and cancel restricted notification. Must be unique within the tethering app.
+    private static final int RESTRICTED_NOTIFICATION_ID = 1001;
     @VisibleForTesting
     static final int NO_ICON_ID = 0;
     @VisibleForTesting
@@ -85,6 +88,9 @@
     // INVALID_SUBSCRIPTION_ID.
     private volatile int mActiveDataSubId = SubscriptionManager.INVALID_SUBSCRIPTION_ID;
 
+    @IntDef({ENABLE_NOTIFICATION_ID, RESTRICTED_NOTIFICATION_ID})
+    @interface NotificationId {}
+
     public TetheringNotificationUpdater(@NonNull final Context context) {
         mContext = context;
         mNotificationManager = (NotificationManager) context.createContextAsUser(UserHandle.ALL, 0)
@@ -100,14 +106,14 @@
     public void onDownstreamChanged(@IntRange(from = 0, to = 7) final int downstreamTypesMask) {
         if (mDownstreamTypesMask == downstreamTypesMask) return;
         mDownstreamTypesMask = downstreamTypesMask;
-        updateNotification();
+        updateEnableNotification();
     }
 
     /** Called when active data subscription id changed */
     public void onActiveDataSubscriptionIdChanged(final int subId) {
         if (mActiveDataSubId == subId) return;
         mActiveDataSubId = subId;
-        updateNotification();
+        updateEnableNotification();
     }
 
     @VisibleForTesting
@@ -115,16 +121,31 @@
         return SubscriptionManager.getResourcesForSubId(c, subId);
     }
 
-    private void updateNotification() {
+    private void updateEnableNotification() {
         final boolean tetheringInactive = mDownstreamTypesMask <= DOWNSTREAM_NONE;
 
         if (tetheringInactive || setupNotification() == NO_NOTIFY) {
-            clearNotification();
+            clearNotification(ENABLE_NOTIFICATION_ID);
         }
     }
 
-    private void clearNotification() {
-        mNotificationManager.cancel(null /* tag */, NOTIFY_ID);
+    @VisibleForTesting
+    void tetheringRestrictionLifted() {
+        clearNotification(RESTRICTED_NOTIFICATION_ID);
+    }
+
+    private void clearNotification(@NotificationId final int id) {
+        mNotificationManager.cancel(null /* tag */, id);
+    }
+
+    @VisibleForTesting
+    void notifyTetheringDisabledByRestriction() {
+        final Resources res = getResourcesForSubId(mContext, mActiveDataSubId);
+        final String title = res.getString(R.string.disable_tether_notification_title);
+        final String message = res.getString(R.string.disable_tether_notification_message);
+
+        showNotification(R.drawable.stat_sys_tether_general, title, message,
+                RESTRICTED_NOTIFICATION_ID);
     }
 
     /**
@@ -195,12 +216,12 @@
         final String title = res.getString(R.string.tethering_notification_title);
         final String message = res.getString(R.string.tethering_notification_message);
 
-        showNotification(iconId, title, message);
+        showNotification(iconId, title, message, ENABLE_NOTIFICATION_ID);
         return NOTIFY_DONE;
     }
 
     private void showNotification(@DrawableRes final int iconId, @NonNull final String title,
-            @NonNull final String message) {
+            @NonNull final String message, @NotificationId final int id) {
         final Intent intent = new Intent(Settings.ACTION_TETHER_SETTINGS);
         final PendingIntent pi = PendingIntent.getActivity(
                 mContext.createContextAsUser(UserHandle.CURRENT, 0),
@@ -218,6 +239,6 @@
                         .setContentIntent(pi)
                         .build();
 
-        mNotificationManager.notify(null /* tag */, NOTIFY_ID, notification);
+        mNotificationManager.notify(null /* tag */, id, notification);
     }
 }
diff --git a/Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringNotificationUpdaterTest.kt b/Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringNotificationUpdaterTest.kt
index 124f9f4..b869491 100644
--- a/Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringNotificationUpdaterTest.kt
+++ b/Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringNotificationUpdaterTest.kt
@@ -25,7 +25,7 @@
 import android.net.ConnectivityManager.TETHERING_WIFI
 import android.os.UserHandle
 import android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID
-import androidx.test.InstrumentationRegistry
+import androidx.test.platform.app.InstrumentationRegistry
 import androidx.test.filters.SmallTest
 import androidx.test.runner.AndroidJUnit4
 import com.android.internal.util.test.BroadcastInterceptingContext
@@ -114,7 +114,7 @@
     @Before
     fun setUp() {
         MockitoAnnotations.initMocks(this)
-        val context = TestContext(InstrumentationRegistry.getContext())
+        val context = TestContext(InstrumentationRegistry.getInstrumentation().context)
         doReturn(notificationManager).`when`(mockContext)
                 .getSystemService(Context.NOTIFICATION_SERVICE)
         notificationUpdater = WrappedNotificationUpdater(context)
@@ -128,7 +128,8 @@
         verify(notificationManager, never()).cancel(any(), anyInt())
 
         val notificationCaptor = ArgumentCaptor.forClass(Notification::class.java)
-        verify(notificationManager, times(1)).notify(any(), anyInt(), notificationCaptor.capture())
+        verify(notificationManager, times(1))
+                .notify(any(), anyInt(), notificationCaptor.capture())
 
         val notification = notificationCaptor.getValue()
         assertEquals(iconId, notification.smallIcon.resId)
@@ -224,4 +225,38 @@
         assertEquals(WIFI_MASK or USB_MASK,
                 notificationUpdater.getDownstreamTypesMask("1|2|USB|WIFI|BLUETOOTH||"))
     }
+
+    @Test
+    fun testSetupRestrictedNotification() {
+        val title = InstrumentationRegistry.getInstrumentation().context.resources
+                .getString(R.string.disable_tether_notification_title)
+        val message = InstrumentationRegistry.getInstrumentation().context.resources
+                .getString(R.string.disable_tether_notification_message)
+        val disallowTitle = "Tether function is disallowed"
+        val disallowMessage = "Please contact your admin"
+        doReturn(title).`when`(defaultResources)
+                .getString(R.string.disable_tether_notification_title)
+        doReturn(message).`when`(defaultResources)
+                .getString(R.string.disable_tether_notification_message)
+        doReturn(disallowTitle).`when`(testResources)
+                .getString(R.string.disable_tether_notification_title)
+        doReturn(disallowMessage).`when`(testResources)
+                .getString(R.string.disable_tether_notification_message)
+
+        // User restrictions on. Show restricted notification.
+        notificationUpdater.notifyTetheringDisabledByRestriction()
+        verifyNotification(R.drawable.stat_sys_tether_general, title, message)
+
+        // User restrictions off. Clear notification.
+        notificationUpdater.tetheringRestrictionLifted()
+        verifyNoNotification()
+
+        // Set test sub id. No notification.
+        notificationUpdater.onActiveDataSubscriptionIdChanged(TEST_SUBID)
+        verifyNoNotification()
+
+        // User restrictions on again. Show restricted notification with test resource.
+        notificationUpdater.notifyTetheringDisabledByRestriction()
+        verifyNotification(R.drawable.stat_sys_tether_general, disallowTitle, disallowMessage)
+    }
 }
\ No newline at end of file
diff --git a/Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringTest.java b/Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringTest.java
index 8116f9d..5ead110 100644
--- a/Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringTest.java
+++ b/Tethering/tests/unit/src/com/android/server/connectivity/tethering/TetheringTest.java
@@ -1072,13 +1072,15 @@
         when(mUserManager.getUserRestrictions()).thenReturn(newRestrictions);
 
         final Tethering.UserRestrictionActionListener ural =
-                new Tethering.UserRestrictionActionListener(mUserManager, mockTethering);
+                new Tethering.UserRestrictionActionListener(
+                        mUserManager, mockTethering, mNotificationUpdater);
         ural.mDisallowTethering = currentDisallow;
 
         ural.onUserRestrictionsChanged();
 
-        verify(mockTethering, times(expectedInteractionsWithShowNotification))
-                .untetherAll();
+        verify(mNotificationUpdater, times(expectedInteractionsWithShowNotification))
+                .notifyTetheringDisabledByRestriction();
+        verify(mockTethering, times(expectedInteractionsWithShowNotification)).untetherAll();
     }
 
     @Test
@@ -1086,7 +1088,7 @@
         final String[] emptyActiveIfacesList = new String[]{};
         final boolean currDisallow = false;
         final boolean nextDisallow = true;
-        final int expectedInteractionsWithShowNotification = 0;
+        final int expectedInteractionsWithShowNotification = 1;
 
         runUserRestrictionsChange(currDisallow, nextDisallow, emptyActiveIfacesList,
                 expectedInteractionsWithShowNotification);