diff --git a/Tethering/Android.bp b/Tethering/Android.bp
index 797b713..d297f3f 100644
--- a/Tethering/Android.bp
+++ b/Tethering/Android.bp
@@ -123,4 +123,5 @@
     use_embedded_native_libs: true,
     // The permission configuration *must* be included to ensure security of the device
     required: ["NetworkPermissionConfig"],
+    apex_available: ["com.android.tethering"],
 }
diff --git a/Tethering/AndroidManifest.xml b/Tethering/AndroidManifest.xml
index 87a8c3f..e99c2c5 100644
--- a/Tethering/AndroidManifest.xml
+++ b/Tethering/AndroidManifest.xml
@@ -33,6 +33,7 @@
     <uses-permission android:name="android.permission.MANAGE_USB" />
     <uses-permission android:name="android.permission.MODIFY_PHONE_STATE" />
     <uses-permission android:name="android.permission.READ_NETWORK_USAGE_HISTORY" />
+    <uses-permission android:name="android.permission.TETHER_PRIVILEGED" />
     <uses-permission android:name="android.permission.UPDATE_APP_OPS_STATS" />
     <uses-permission android:name="android.permission.WRITE_SETTINGS" />
 
diff --git a/Tethering/common/TetheringLib/Android.bp b/Tethering/common/TetheringLib/Android.bp
index 5785707..264ce44 100644
--- a/Tethering/common/TetheringLib/Android.bp
+++ b/Tethering/common/TetheringLib/Android.bp
@@ -47,6 +47,16 @@
     libs: [
         "android_system_stubs_current",
     ],
+
+    hostdex: true, // for hiddenapi check
+    visibility: [
+        "//frameworks/base/packages/Tethering:__subpackages__",
+        //TODO(b/147200698) remove below lines when the platform is built with stubs
+        "//frameworks/base",
+        "//frameworks/base/services",
+        "//frameworks/base/services/core",
+    ],
+    apex_available: ["com.android.tethering"],
 }
 
 filegroup {
diff --git a/Tethering/res/values/strings.xml b/Tethering/res/values/strings.xml
index ca866a9..792bce9 100644
--- a/Tethering/res/values/strings.xml
+++ b/Tethering/res/values/strings.xml
@@ -1,4 +1,18 @@
 <?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2020 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
 <resources>
     <!-- Shown when the device is tethered -->
     <!-- Strings for tethered notification title [CHAR LIMIT=200] -->
@@ -9,8 +23,11 @@
     <!-- This notification is shown when tethering has been disabled on a user's device.
     The device is managed by the user's employer. Tethering can't be turned on unless the
     IT administrator allows it. The noun "admin" is another reference for "IT administrator." -->
-    <!-- Strings for tether disabling notification title  [CHAR LIMIT=200] -->
+    <!-- Strings for tether disabling notification title [CHAR LIMIT=200] -->
     <string name="disable_tether_notification_title">Tethering is disabled</string>
-    <!-- Strings for tether disabling notification message  [CHAR LIMIT=200] -->
+    <!-- Strings for tether disabling notification message [CHAR LIMIT=200] -->
     <string name="disable_tether_notification_message">Contact your admin for details</string>
+
+    <!-- Strings for tether notification channel name [CHAR LIMIT=200] -->
+    <string name="notification_channel_tethering_status">Hotspot &amp; tethering status</string>
 </resources>
\ No newline at end of file
diff --git a/Tethering/src/com/android/server/connectivity/tethering/Tethering.java b/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
index 2119791..5b97f50 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
@@ -50,6 +50,7 @@
 import static android.telephony.SubscriptionManager.INVALID_SUBSCRIPTION_ID;
 
 import android.app.Notification;
+import android.app.NotificationChannel;
 import android.app.NotificationManager;
 import android.app.PendingIntent;
 import android.bluetooth.BluetoothAdapter;
@@ -106,8 +107,6 @@
 import androidx.annotation.Nullable;
 
 import com.android.internal.annotations.VisibleForTesting;
-import com.android.internal.messages.nano.SystemMessageProto.SystemMessage;
-import com.android.internal.notification.SystemNotificationChannels;
 import com.android.internal.util.IndentingPrintWriter;
 import com.android.internal.util.MessageUtils;
 import com.android.internal.util.State;
@@ -663,19 +662,19 @@
 
         if (usbTethered) {
             if (wifiTethered || bluetoothTethered) {
-                showTetheredNotification(SystemMessage.NOTE_TETHER_GENERAL);
+                showTetheredNotification(R.drawable.stat_sys_tether_general);
             } else {
-                showTetheredNotification(SystemMessage.NOTE_TETHER_USB);
+                showTetheredNotification(R.drawable.stat_sys_tether_usb);
             }
         } else if (wifiTethered) {
             if (bluetoothTethered) {
-                showTetheredNotification(SystemMessage.NOTE_TETHER_GENERAL);
+                showTetheredNotification(R.drawable.stat_sys_tether_general);
             } else {
                 /* We now have a status bar icon for WifiTethering, so drop the notification */
                 clearTetheredNotification();
             }
         } else if (bluetoothTethered) {
-            showTetheredNotification(SystemMessage.NOTE_TETHER_BLUETOOTH);
+            showTetheredNotification(R.drawable.stat_sys_tether_bluetooth);
         } else {
             clearTetheredNotification();
         }
@@ -688,30 +687,22 @@
     @VisibleForTesting
     protected void showTetheredNotification(int id, boolean tetheringOn) {
         NotificationManager notificationManager =
-                (NotificationManager) mContext.getSystemService(Context.NOTIFICATION_SERVICE);
+                (NotificationManager) mContext.createContextAsUser(UserHandle.ALL, 0)
+                        .getSystemService(Context.NOTIFICATION_SERVICE);
         if (notificationManager == null) {
             return;
         }
-        int icon = 0;
-        switch(id) {
-            case SystemMessage.NOTE_TETHER_USB:
-                icon = R.drawable.stat_sys_tether_usb;
-                break;
-            case SystemMessage.NOTE_TETHER_BLUETOOTH:
-                icon = R.drawable.stat_sys_tether_bluetooth;
-                break;
-            case SystemMessage.NOTE_TETHER_GENERAL:
-            default:
-                icon = R.drawable.stat_sys_tether_general;
-                break;
-        }
+        final NotificationChannel channel = new NotificationChannel(
+                "TETHERING_STATUS",
+                mContext.getResources().getString(R.string.notification_channel_tethering_status),
+                NotificationManager.IMPORTANCE_LOW);
+        notificationManager.createNotificationChannel(channel);
 
         if (mLastNotificationId != 0) {
-            if (mLastNotificationId == icon) {
+            if (mLastNotificationId == id) {
                 return;
             }
-            notificationManager.cancelAsUser(null, mLastNotificationId,
-                    UserHandle.ALL);
+            notificationManager.cancel(null, mLastNotificationId);
             mLastNotificationId = 0;
         }
 
@@ -719,8 +710,8 @@
         intent.setClassName("com.android.settings", "com.android.settings.TetherSettings");
         intent.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
 
-        PendingIntent pi = PendingIntent.getActivityAsUser(mContext, 0, intent, 0,
-                null, UserHandle.CURRENT);
+        PendingIntent pi = PendingIntent.getActivity(
+                mContext.createContextAsUser(UserHandle.CURRENT, 0), 0, intent, 0, null);
 
         Resources r = mContext.getResources();
         final CharSequence title;
@@ -735,32 +726,31 @@
         }
 
         if (mTetheredNotificationBuilder == null) {
-            mTetheredNotificationBuilder = new Notification.Builder(mContext,
-                    SystemNotificationChannels.NETWORK_STATUS);
+            mTetheredNotificationBuilder = new Notification.Builder(mContext, channel.getId());
             mTetheredNotificationBuilder.setWhen(0)
                     .setOngoing(true)
                     .setColor(mContext.getColor(
-                            com.android.internal.R.color.system_notification_accent_color))
+                            android.R.color.system_notification_accent_color))
                     .setVisibility(Notification.VISIBILITY_PUBLIC)
                     .setCategory(Notification.CATEGORY_STATUS);
         }
-        mTetheredNotificationBuilder.setSmallIcon(icon)
+        mTetheredNotificationBuilder.setSmallIcon(id)
                 .setContentTitle(title)
                 .setContentText(message)
                 .setContentIntent(pi);
         mLastNotificationId = id;
 
-        notificationManager.notifyAsUser(null, mLastNotificationId,
-                mTetheredNotificationBuilder.buildInto(new Notification()), UserHandle.ALL);
+        notificationManager.notify(null, mLastNotificationId,
+                mTetheredNotificationBuilder.buildInto(new Notification()));
     }
 
     @VisibleForTesting
     protected void clearTetheredNotification() {
         NotificationManager notificationManager =
-                (NotificationManager) mContext.getSystemService(Context.NOTIFICATION_SERVICE);
+                (NotificationManager) mContext.createContextAsUser(UserHandle.ALL, 0)
+                        .getSystemService(Context.NOTIFICATION_SERVICE);
         if (notificationManager != null && mLastNotificationId != 0) {
-            notificationManager.cancelAsUser(null, mLastNotificationId,
-                    UserHandle.ALL);
+            notificationManager.cancel(null, mLastNotificationId);
             mLastNotificationId = 0;
         }
     }
diff --git a/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java b/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java
index fe3f517..5692a6f 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java
@@ -16,9 +16,12 @@
 
 package com.android.server.connectivity.tethering;
 
+import static android.net.ConnectivityManager.TYPE_BLUETOOTH;
+import static android.net.ConnectivityManager.TYPE_ETHERNET;
+import static android.net.ConnectivityManager.TYPE_MOBILE;
 import static android.net.ConnectivityManager.TYPE_MOBILE_DUN;
 import static android.net.ConnectivityManager.TYPE_MOBILE_HIPRI;
-import static android.net.ConnectivityManager.TYPE_NONE;
+import static android.net.ConnectivityManager.TYPE_WIFI;
 import static android.net.NetworkCapabilities.NET_CAPABILITY_DUN;
 import static android.net.NetworkCapabilities.NET_CAPABILITY_NOT_VPN;
 import static android.net.NetworkCapabilities.TRANSPORT_CELLULAR;
@@ -35,8 +38,10 @@
 import android.net.util.SharedLog;
 import android.os.Handler;
 import android.util.Log;
+import android.util.SparseIntArray;
 
 import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.util.Preconditions;
 import com.android.internal.util.StateMachine;
 
 import java.util.HashMap;
@@ -77,11 +82,25 @@
     public static final int EVENT_ON_LINKPROPERTIES = 2;
     public static final int EVENT_ON_LOST           = 3;
     public static final int NOTIFY_LOCAL_PREFIXES   = 10;
+    // This value is used by deprecated preferredUpstreamIfaceTypes selection which is default
+    // disabled.
+    @VisibleForTesting
+    public static final int TYPE_NONE = -1;
 
     private static final int CALLBACK_LISTEN_ALL = 1;
     private static final int CALLBACK_DEFAULT_INTERNET = 2;
     private static final int CALLBACK_MOBILE_REQUEST = 3;
 
+    private static final SparseIntArray sLegacyTypeToTransport = new SparseIntArray();
+    static {
+        sLegacyTypeToTransport.put(TYPE_MOBILE,       NetworkCapabilities.TRANSPORT_CELLULAR);
+        sLegacyTypeToTransport.put(TYPE_MOBILE_DUN,   NetworkCapabilities.TRANSPORT_CELLULAR);
+        sLegacyTypeToTransport.put(TYPE_MOBILE_HIPRI, NetworkCapabilities.TRANSPORT_CELLULAR);
+        sLegacyTypeToTransport.put(TYPE_WIFI,         NetworkCapabilities.TRANSPORT_WIFI);
+        sLegacyTypeToTransport.put(TYPE_BLUETOOTH,    NetworkCapabilities.TRANSPORT_BLUETOOTH);
+        sLegacyTypeToTransport.put(TYPE_ETHERNET,     NetworkCapabilities.TRANSPORT_ETHERNET);
+    }
+
     private final Context mContext;
     private final SharedLog mLog;
     private final StateMachine mTarget;
@@ -202,7 +221,7 @@
         final int legacyType = mDunRequired ? TYPE_MOBILE_DUN : TYPE_MOBILE_HIPRI;
 
         final NetworkRequest mobileUpstreamRequest = new NetworkRequest.Builder()
-                .setCapabilities(ConnectivityManager.networkCapabilitiesForType(legacyType))
+                .setCapabilities(networkCapabilitiesForType(legacyType))
                 .build();
 
         // The existing default network and DUN callbacks will be notified.
@@ -354,16 +373,6 @@
         notifyTarget(EVENT_ON_LINKPROPERTIES, network);
     }
 
-    private void handleSuspended(Network network) {
-        if (!network.equals(mTetheringUpstreamNetwork)) return;
-        mLog.log("SUSPENDED current upstream: " + network);
-    }
-
-    private void handleResumed(Network network) {
-        if (!network.equals(mTetheringUpstreamNetwork)) return;
-        mLog.log("RESUMED current upstream: " + network);
-    }
-
     private void handleLost(Network network) {
         // There are few TODOs within ConnectivityService's rematching code
         // pertaining to spurious onLost() notifications.
@@ -453,20 +462,6 @@
         }
 
         @Override
-        public void onNetworkSuspended(Network network) {
-            if (mCallbackType == CALLBACK_LISTEN_ALL) {
-                handleSuspended(network);
-            }
-        }
-
-        @Override
-        public void onNetworkResumed(Network network) {
-            if (mCallbackType == CALLBACK_LISTEN_ALL) {
-                handleResumed(network);
-            }
-        }
-
-        @Override
         public void onLost(Network network) {
             if (mCallbackType == CALLBACK_DEFAULT_INTERNET) {
                 mDefaultInternetNetwork = null;
@@ -510,7 +505,7 @@
         for (int type : preferredTypes) {
             NetworkCapabilities nc;
             try {
-                nc = ConnectivityManager.networkCapabilitiesForType(type);
+                nc = networkCapabilitiesForType(type);
             } catch (IllegalArgumentException iae) {
                 Log.e(TAG, "No NetworkCapabilities mapping for legacy type: " + type);
                 continue;
@@ -572,4 +567,28 @@
 
         return null;
     }
+
+    /**
+     * Given a legacy type (TYPE_WIFI, ...) returns the corresponding NetworkCapabilities instance.
+     * This function is used for deprecated legacy type and be disabled by default.
+     */
+    @VisibleForTesting
+    public static NetworkCapabilities networkCapabilitiesForType(int type) {
+        final NetworkCapabilities nc = new NetworkCapabilities();
+
+        // Map from type to transports.
+        final int notFound = -1;
+        final int transport = sLegacyTypeToTransport.get(type, notFound);
+        Preconditions.checkArgument(transport != notFound, "unknown legacy type: " + type);
+        nc.addTransportType(transport);
+
+        if (type == TYPE_MOBILE_DUN) {
+            nc.addCapability(NetworkCapabilities.NET_CAPABILITY_DUN);
+            // DUN is restricted network, see NetworkCapabilities#FORCE_RESTRICTED_CAPABILITIES.
+            nc.removeCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED);
+        } else {
+            nc.addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
+        }
+        return nc;
+    }
 }
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 5ca21f7..4edde0a 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
@@ -224,6 +224,11 @@
             if (TelephonyManager.class.equals(serviceClass)) return Context.TELEPHONY_SERVICE;
             return super.getSystemServiceName(serviceClass);
         }
+
+        @Override
+        public Context createContextAsUser(UserHandle user, int flags) {
+            return mContext;
+        }
     }
 
     public class MockIpServerDependencies extends IpServer.Dependencies {
@@ -432,6 +437,7 @@
                 .thenReturn(true);
 
         mServiceContext = new TestContext(mContext);
+        when(mContext.getSystemService(Context.NOTIFICATION_SERVICE)).thenReturn(null);
         mContentResolver = new MockContentResolver(mServiceContext);
         mContentResolver.addProvider(Settings.AUTHORITY, new FakeSettingsProvider());
         Settings.Global.putInt(mContentResolver, TETHER_ENABLE_LEGACY_DHCP_SERVER, 0);
diff --git a/Tethering/tests/unit/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitorTest.java b/Tethering/tests/unit/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitorTest.java
index c90abbb..5ed75bf 100644
--- a/Tethering/tests/unit/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitorTest.java
+++ b/Tethering/tests/unit/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitorTest.java
@@ -18,13 +18,14 @@
 
 import static android.net.ConnectivityManager.TYPE_MOBILE_DUN;
 import static android.net.ConnectivityManager.TYPE_MOBILE_HIPRI;
-import static android.net.ConnectivityManager.TYPE_NONE;
 import static android.net.ConnectivityManager.TYPE_WIFI;
 import static android.net.NetworkCapabilities.NET_CAPABILITY_DUN;
 import static android.net.NetworkCapabilities.NET_CAPABILITY_INTERNET;
 import static android.net.NetworkCapabilities.TRANSPORT_CELLULAR;
 import static android.net.NetworkCapabilities.TRANSPORT_WIFI;
 
+import static com.android.server.connectivity.tethering.UpstreamNetworkMonitor.TYPE_NONE;
+
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
@@ -538,13 +539,15 @@
                 mUNM.selectPreferredUpstreamType(preferredTypes));
         verify(mEntitleMgr, times(1)).maybeRunProvisioning();
     }
+
     private void assertSatisfiesLegacyType(int legacyType, UpstreamNetworkState ns) {
         if (legacyType == TYPE_NONE) {
             assertTrue(ns == null);
             return;
         }
 
-        final NetworkCapabilities nc = ConnectivityManager.networkCapabilitiesForType(legacyType);
+        final NetworkCapabilities nc =
+                UpstreamNetworkMonitor.networkCapabilitiesForType(legacyType);
         assertTrue(nc.satisfiedByNetworkCapabilities(ns.networkCapabilities));
     }