diff --git a/Tethering/Android.bp b/Tethering/Android.bp
index 0c37235..0cfd884 100644
--- a/Tethering/Android.bp
+++ b/Tethering/Android.bp
@@ -16,9 +16,7 @@
 
 java_defaults {
     name: "TetheringAndroidLibraryDefaults",
-    // TODO (b/146757305): change to module API once available
-    // TODO (b/148190005): change to module-libs-api-stubs-current once it is ready.
-    sdk_version: "core_platform",
+    sdk_version: "module_current",
     srcs: [
         "src/**/*.java",
         ":framework-tethering-shared-srcs",
@@ -35,15 +33,8 @@
         "net-utils-framework-common",
     ],
     libs: [
-        // Order matters: framework-tethering needs to be before the system stubs, otherwise
-        // hidden fields in the framework-tethering classes (which are also used to generate stubs)
-        // will not be found.
         "framework-tethering",
-        "android_system_stubs_current",
-        "framework-res",
         "unsupportedappusage",
-        "android_system_stubs_current",
-        "framework-res",
     ],
     plugins: ["java_api_finder"],
     manifest: "AndroidManifestBase.xml",
@@ -91,9 +82,7 @@
 // Common defaults for compiling the actual APK.
 java_defaults {
     name: "TetheringAppDefaults",
-    // TODO (b/146757305): change to module API once available
-    // TODO (b/148190005): change to module-libs-api-stubs-current once it is ready.
-    sdk_version: "core_platform",
+    sdk_version: "module_current",
     privileged: true,
     jni_libs: [
         "libtetherutilsjni",
@@ -102,12 +91,7 @@
         "res",
     ],
     libs: [
-        // Order matters: framework-tethering needs to be before the system stubs, otherwise
-        // hidden fields in the framework-tethering classes (which are also used to generate stubs)
-        // will not be found.
         "framework-tethering",
-        "android_system_stubs_current",
-        "framework-res",
     ],
     jarjar_rules: "jarjar-rules.txt",
     optimize: {
diff --git a/Tethering/common/TetheringLib/src/android/net/TetheringManager.java b/Tethering/common/TetheringLib/src/android/net/TetheringManager.java
index 096f4fe..0107a7e 100644
--- a/Tethering/common/TetheringLib/src/android/net/TetheringManager.java
+++ b/Tethering/common/TetheringLib/src/android/net/TetheringManager.java
@@ -571,9 +571,8 @@
             /**
              * Configure tethering with static IPv4 assignment.
              *
-             * The clientAddress must be in the localIPv4Address prefix. A DHCP server will be
-             * started, but will only be able to offer the client address. The two addresses must
-             * be in the same prefix.
+             * A DHCP server will be started, but will only be able to offer the client address.
+             * The two addresses must be in the same prefix.
              *
              * @param localIPv4Address The preferred local IPv4 link address to use.
              * @param clientAddress The static client address.
@@ -584,10 +583,7 @@
                     @NonNull final LinkAddress clientAddress) {
                 Objects.requireNonNull(localIPv4Address);
                 Objects.requireNonNull(clientAddress);
-                if (localIPv4Address.getPrefixLength() != clientAddress.getPrefixLength()
-                        || !localIPv4Address.isIpv4() || !clientAddress.isIpv4()
-                        || !new IpPrefix(localIPv4Address.toString()).equals(
-                        new IpPrefix(clientAddress.toString()))) {
+                if (!checkStaticAddressConfiguration(localIPv4Address, clientAddress)) {
                     throw new IllegalArgumentException("Invalid server or client addresses");
                 }
 
@@ -657,6 +653,19 @@
         }
 
         /**
+         * Check whether the two addresses are ipv4 and in the same prefix.
+         * @hide
+         */
+        public static boolean checkStaticAddressConfiguration(
+                @NonNull final LinkAddress localIPv4Address,
+                @NonNull final LinkAddress clientAddress) {
+            return localIPv4Address.getPrefixLength() == clientAddress.getPrefixLength()
+                    && localIPv4Address.isIpv4() && clientAddress.isIpv4()
+                    && new IpPrefix(localIPv4Address.toString()).equals(
+                    new IpPrefix(clientAddress.toString()));
+        }
+
+        /**
          * Get a TetheringRequestParcel from the configuration
          * @hide
          */
diff --git a/Tethering/src/android/net/dhcp/DhcpServingParamsParcelExt.java b/Tethering/src/android/net/dhcp/DhcpServingParamsParcelExt.java
index d6bc063..82a26be 100644
--- a/Tethering/src/android/net/dhcp/DhcpServingParamsParcelExt.java
+++ b/Tethering/src/android/net/dhcp/DhcpServingParamsParcelExt.java
@@ -18,10 +18,12 @@
 
 import static android.net.shared.Inet4AddressUtils.inet4AddressToIntHTH;
 
-import android.annotation.NonNull;
 import android.net.LinkAddress;
 import android.util.ArraySet;
 
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+
 import java.net.Inet4Address;
 import java.util.Collection;
 import java.util.Collections;
@@ -160,6 +162,17 @@
         return this;
     }
 
+    /**
+     * Set the client address to tell DHCP server only offer this address.
+     * The client's prefix length is the same as server's.
+     *
+     * <p>If not set, the default value is null.
+     */
+    public DhcpServingParamsParcelExt setSingleClientAddr(@Nullable Inet4Address clientAddr) {
+        this.clientAddr = clientAddr == null ? 0 : inet4AddressToIntHTH(clientAddr);
+        return this;
+    }
+
     private static int[] toIntArray(@NonNull Collection<Inet4Address> addrs) {
         int[] res = new int[addrs.size()];
         int i = 0;
diff --git a/Tethering/src/android/net/ip/IpServer.java b/Tethering/src/android/net/ip/IpServer.java
index c5478d2..82b17ac 100644
--- a/Tethering/src/android/net/ip/IpServer.java
+++ b/Tethering/src/android/net/ip/IpServer.java
@@ -18,6 +18,7 @@
 
 import static android.net.InetAddresses.parseNumericAddress;
 import static android.net.RouteInfo.RTN_UNICAST;
+import static android.net.TetheringManager.TetheringRequest.checkStaticAddressConfiguration;
 import static android.net.dhcp.IDhcpServer.STATUS_SUCCESS;
 import static android.net.shared.Inet4AddressUtils.intToInet4AddressHTH;
 import static android.net.util.NetworkConstants.FF;
@@ -492,17 +493,24 @@
         }
     }
 
-    private boolean startDhcp(Inet4Address addr, int prefixLen) {
+    private boolean startDhcp(final LinkAddress serverLinkAddr, final LinkAddress clientLinkAddr) {
         if (mUsingLegacyDhcp) {
             return true;
         }
+
+        final Inet4Address addr = (Inet4Address) serverLinkAddr.getAddress();
+        final int prefixLen = serverLinkAddr.getPrefixLength();
+        final Inet4Address clientAddr = clientLinkAddr == null ? null :
+                (Inet4Address) clientLinkAddr.getAddress();
+
         final DhcpServingParamsParcel params;
         params = new DhcpServingParamsParcelExt()
                 .setDefaultRouters(addr)
                 .setDhcpLeaseTimeSecs(DHCP_LEASE_TIME_SECS)
                 .setDnsServers(addr)
-                .setServerAddr(new LinkAddress(addr, prefixLen))
-                .setMetered(true);
+                .setServerAddr(serverLinkAddr)
+                .setMetered(true)
+                .setSingleClientAddr(clientAddr);
         // TODO: also advertise link MTU
 
         mDhcpServerStartIndex++;
@@ -537,9 +545,10 @@
         }
     }
 
-    private boolean configureDhcp(boolean enable, Inet4Address addr, int prefixLen) {
+    private boolean configureDhcp(boolean enable, final LinkAddress serverAddr,
+            final LinkAddress clientAddr) {
         if (enable) {
-            return startDhcp(addr, prefixLen);
+            return startDhcp(serverAddr, clientAddr);
         } else {
             stopDhcp();
             return true;
@@ -587,7 +596,7 @@
                 // code that calls into NetworkManagementService directly.
                 srvAddr = (Inet4Address) parseNumericAddress(BLUETOOTH_IFACE_ADDR);
                 mIpv4Address = new LinkAddress(srvAddr, BLUETOOTH_DHCP_PREFIX_LENGTH);
-                return configureDhcp(enabled, srvAddr, BLUETOOTH_DHCP_PREFIX_LENGTH);
+                return configureDhcp(enabled, mIpv4Address, null /* clientAddress */);
             }
             mIpv4Address = new LinkAddress(srvAddr, prefixLen);
         } catch (IllegalArgumentException e) {
@@ -624,7 +633,7 @@
             mLinkProperties.removeRoute(route);
         }
 
-        return configureDhcp(enabled, srvAddr, prefixLen);
+        return configureDhcp(enabled, mIpv4Address, mStaticIpv4ClientAddr);
     }
 
     private String getRandomWifiIPv4Address() {
@@ -945,7 +954,14 @@
     }
 
     private void maybeConfigureStaticIp(final TetheringRequestParcel request) {
-        if (request == null) return;
+        // Ignore static address configuration if they are invalid or null. In theory, static
+        // addresses should not be invalid here because TetheringManager do not allow caller to
+        // specify invalid static address configuration.
+        if (request == null || request.localIPv4Address == null
+                || request.staticClientAddress == null || !checkStaticAddressConfiguration(
+                request.localIPv4Address, request.staticClientAddress)) {
+            return;
+        }
 
         mStaticIpv4ServerAddr = request.localIPv4Address;
         mStaticIpv4ClientAddr = request.staticClientAddress;
diff --git a/Tethering/src/com/android/server/connectivity/tethering/Tethering.java b/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
index 020db54..343ed4b 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/Tethering.java
@@ -307,28 +307,22 @@
                 userManager, this, mNotificationUpdater);
         mExecutor = new TetheringThreadExecutor(mHandler);
         mActiveDataSubIdListener = new ActiveDataSubIdListener(mExecutor);
+        mNetdCallback = new NetdCallback();
 
         // Load tethering configuration.
         updateConfiguration();
-        // NetdCallback should be registered after updateConfiguration() to ensure
-        // TetheringConfiguration is created.
-        mNetdCallback = new NetdCallback();
+    }
+
+    /**
+     * Start to register callbacks.
+     * Call this function when tethering is ready to handle callback events.
+     */
+    public void startStateMachineUpdaters() {
         try {
             mNetd.registerUnsolicitedEventListener(mNetdCallback);
         } catch (RemoteException e) {
             mLog.e("Unable to register netd UnsolicitedEventListener");
         }
-
-        startStateMachineUpdaters(mHandler);
-        startTrackDefaultNetwork();
-
-        final WifiManager wifiManager = getWifiManager();
-        if (wifiManager != null) {
-            wifiManager.registerSoftApCallback(mExecutor, new TetheringSoftApCallback());
-        }
-    }
-
-    private void startStateMachineUpdaters(Handler handler) {
         mCarrierConfigChange.startListening();
         mContext.getSystemService(TelephonyManager.class).listen(mActiveDataSubIdListener,
                 PhoneStateListener.LISTEN_ACTIVE_DATA_SUBSCRIPTION_ID_CHANGE);
@@ -341,7 +335,14 @@
         filter.addAction(WifiP2pManager.WIFI_P2P_CONNECTION_CHANGED_ACTION);
         filter.addAction(UserManager.ACTION_USER_RESTRICTIONS_CHANGED);
         filter.addAction(ACTION_RESTRICT_BACKGROUND_CHANGED);
-        mContext.registerReceiver(mStateReceiver, filter, null, handler);
+        mContext.registerReceiver(mStateReceiver, filter, null, mHandler);
+
+        final WifiManager wifiManager = getWifiManager();
+        if (wifiManager != null) {
+            wifiManager.registerSoftApCallback(mExecutor, new TetheringSoftApCallback());
+        }
+
+        startTrackDefaultNetwork();
     }
 
     private class TetheringThreadExecutor implements Executor {
diff --git a/Tethering/src/com/android/server/connectivity/tethering/TetheringService.java b/Tethering/src/com/android/server/connectivity/tethering/TetheringService.java
index c5329d8..c30be25 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/TetheringService.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/TetheringService.java
@@ -80,6 +80,7 @@
         mContext = mDeps.getContext();
         mUserManager = (UserManager) mContext.getSystemService(Context.USER_SERVICE);
         mTethering = makeTethering(mDeps);
+        mTethering.startStateMachineUpdaters();
     }
 
     /**
diff --git a/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java b/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java
index 7ac7f5f..45bb4ab 100644
--- a/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java
+++ b/Tethering/src/com/android/server/connectivity/tethering/UpstreamNetworkMonitor.java
@@ -586,21 +586,21 @@
      */
     @VisibleForTesting
     public static NetworkCapabilities networkCapabilitiesForType(int type) {
-        final NetworkCapabilities nc = new NetworkCapabilities();
+        final NetworkCapabilities.Builder builder = new NetworkCapabilities.Builder();
 
         // 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);
+        builder.addTransportType(transport);
 
         if (type == TYPE_MOBILE_DUN) {
-            nc.addCapability(NetworkCapabilities.NET_CAPABILITY_DUN);
+            builder.addCapability(NetworkCapabilities.NET_CAPABILITY_DUN);
             // DUN is restricted network, see NetworkCapabilities#FORCE_RESTRICTED_CAPABILITIES.
-            nc.removeCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED);
+            builder.removeCapability(NetworkCapabilities.NET_CAPABILITY_NOT_RESTRICTED);
         } else {
-            nc.addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
+            builder.addCapability(NetworkCapabilities.NET_CAPABILITY_INTERNET);
         }
-        return nc;
+        return builder.build();
     }
 }
diff --git a/Tethering/tests/integration/Android.bp b/Tethering/tests/integration/Android.bp
new file mode 100644
index 0000000..1a1c30d
--- /dev/null
+++ b/Tethering/tests/integration/Android.bp
@@ -0,0 +1,42 @@
+//
+// 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.
+//
+
+android_test {
+    name: "TetheringIntegrationTests",
+    certificate: "platform",
+    platform_apis: true,
+    srcs: [
+        "src/**/*.java",
+        "src/**/*.kt",
+    ],
+    test_suites: [
+        "device-tests",
+        "mts",
+    ],
+    static_libs: [
+        "NetworkStackApiStableLib",
+        "androidx.test.rules",
+        "frameworks-base-testutils",
+        "mockito-target-extended-minus-junit4",
+        "net-tests-utils",
+        "testables",
+    ],
+    libs: [
+        "android.test.runner",
+        "android.test.base",
+        "android.test.mock",
+    ],
+}
diff --git a/Tethering/tests/integration/AndroidManifest.xml b/Tethering/tests/integration/AndroidManifest.xml
new file mode 100644
index 0000000..233ba40
--- /dev/null
+++ b/Tethering/tests/integration/AndroidManifest.xml
@@ -0,0 +1,29 @@
+<?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.
+-->
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+          package="com.android.networkstack.tethering.tests.integration">
+
+    <uses-permission android:name="android.permission.INTERNET"/>
+    <uses-permission android:name="android.permission.TETHER_PRIVILEGED"/>
+
+    <application android:debuggable="true">
+        <uses-library android:name="android.test.runner" />
+    </application>
+    <instrumentation android:name="androidx.test.runner.AndroidJUnitRunner"
+        android:targetPackage="com.android.networkstack.tethering.tests.integration"
+        android:label="Tethering integration tests">
+    </instrumentation>
+</manifest>
diff --git a/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
new file mode 100644
index 0000000..492ce3d
--- /dev/null
+++ b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
@@ -0,0 +1,459 @@
+/*
+ * 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.
+ */
+
+package android.net;
+
+import static android.Manifest.permission.MANAGE_TEST_NETWORKS;
+import static android.Manifest.permission.NETWORK_SETTINGS;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.junit.Assume.assumeFalse;
+import static org.junit.Assume.assumeTrue;
+
+import android.app.UiAutomation;
+import android.content.Context;
+import android.net.EthernetManager.TetheredInterfaceCallback;
+import android.net.EthernetManager.TetheredInterfaceRequest;
+import android.net.TetheringManager.StartTetheringCallback;
+import android.net.TetheringManager.TetheringEventCallback;
+import android.net.TetheringManager.TetheringRequest;
+import android.net.dhcp.DhcpAckPacket;
+import android.net.dhcp.DhcpOfferPacket;
+import android.net.dhcp.DhcpPacket;
+import android.os.Handler;
+import android.os.HandlerThread;
+import android.os.SystemClock;
+import android.system.Os;
+import android.util.Log;
+
+import androidx.test.InstrumentationRegistry;
+import androidx.test.filters.MediumTest;
+import androidx.test.runner.AndroidJUnit4;
+
+import com.android.testutils.HandlerUtilsKt;
+import com.android.testutils.TapPacketReader;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import java.io.FileDescriptor;
+import java.net.Inet4Address;
+import java.net.NetworkInterface;
+import java.net.SocketException;
+import java.nio.ByteBuffer;
+import java.util.Collection;
+import java.util.List;
+import java.util.Random;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+@RunWith(AndroidJUnit4.class)
+@MediumTest
+public class EthernetTetheringTest {
+
+    private static final String TAG = EthernetTetheringTest.class.getSimpleName();
+    private static final int TIMEOUT_MS = 1000;
+    private static final int PACKET_READ_TIMEOUT_MS = 100;
+    private static final int DHCP_DISCOVER_ATTEMPTS = 10;
+    private static final byte[] DHCP_REQUESTED_PARAMS = new byte[] {
+            DhcpPacket.DHCP_SUBNET_MASK,
+            DhcpPacket.DHCP_ROUTER,
+            DhcpPacket.DHCP_DNS_SERVER,
+            DhcpPacket.DHCP_LEASE_TIME,
+    };
+    private static final String DHCP_HOSTNAME = "testhostname";
+
+    private final Context mContext = InstrumentationRegistry.getContext();
+    private final EthernetManager mEm = mContext.getSystemService(EthernetManager.class);
+    private final TetheringManager mTm = mContext.getSystemService(TetheringManager.class);
+
+    private TestNetworkInterface mTestIface;
+    private HandlerThread mHandlerThread;
+    private Handler mHandler;
+    private TapPacketReader mTapPacketReader;
+
+    private TetheredInterfaceRequester mTetheredInterfaceRequester;
+    private MyTetheringEventCallback mTetheringEventCallback;
+
+    private UiAutomation mUiAutomation =
+            InstrumentationRegistry.getInstrumentation().getUiAutomation();
+
+    @Before
+    public void setUp() throws Exception {
+        mHandlerThread = new HandlerThread(getClass().getSimpleName());
+        mHandlerThread.start();
+        mHandler = new Handler(mHandlerThread.getLooper());
+        mTetheredInterfaceRequester = new TetheredInterfaceRequester(mHandler, mEm);
+        // Needed to create a TestNetworkInterface, to call requestTetheredInterface, and to receive
+        // tethered client callbacks.
+        mUiAutomation.adoptShellPermissionIdentity(MANAGE_TEST_NETWORKS, NETWORK_SETTINGS);
+    }
+
+    private void cleanUp() throws Exception {
+        mTm.stopTethering(TetheringManager.TETHERING_ETHERNET);
+        if (mTetheringEventCallback != null) {
+            mTetheringEventCallback.awaitInterfaceUntethered();
+            mTetheringEventCallback.unregister();
+            mTetheringEventCallback = null;
+        }
+        if (mTapPacketReader != null) {
+            TapPacketReader reader = mTapPacketReader;
+            mHandler.post(() -> reader.stop());
+            mTapPacketReader = null;
+        }
+        mHandlerThread.quitSafely();
+        mTetheredInterfaceRequester.release();
+        mEm.setIncludeTestInterfaces(false);
+        maybeDeleteTestInterface();
+    }
+
+    @After
+    public void tearDown() throws Exception {
+        try {
+            cleanUp();
+        } finally {
+            mUiAutomation.dropShellPermissionIdentity();
+        }
+    }
+
+    @Test
+    public void testVirtualEthernetAlreadyExists() throws Exception {
+        // This test requires manipulating packets. Skip if there is a physical Ethernet connected.
+        assumeFalse(mEm.isAvailable());
+
+        mTestIface = createTestInterface();
+        // This must be done now because as soon as setIncludeTestInterfaces(true) is called, the
+        // interface will be placed in client mode, which will delete the link-local address.
+        // At that point NetworkInterface.getByName() will cease to work on the interface, because
+        // starting in R NetworkInterface can no longer see interfaces without IP addresses.
+        int mtu = getMTU(mTestIface);
+
+        Log.d(TAG, "Including test interfaces");
+        mEm.setIncludeTestInterfaces(true);
+
+        final String iface = mTetheredInterfaceRequester.getInterface();
+        assertEquals("TetheredInterfaceCallback for unexpected interface",
+                mTestIface.getInterfaceName(), iface);
+
+        checkVirtualEthernet(mTestIface, mtu);
+    }
+
+    @Test
+    public void testVirtualEthernet() throws Exception {
+        // This test requires manipulating packets. Skip if there is a physical Ethernet connected.
+        assumeFalse(mEm.isAvailable());
+
+        CompletableFuture<String> futureIface = mTetheredInterfaceRequester.requestInterface();
+
+        mEm.setIncludeTestInterfaces(true);
+
+        mTestIface = createTestInterface();
+
+        final String iface = futureIface.get(TIMEOUT_MS, TimeUnit.MILLISECONDS);
+        assertEquals("TetheredInterfaceCallback for unexpected interface",
+                mTestIface.getInterfaceName(), iface);
+
+        checkVirtualEthernet(mTestIface, getMTU(mTestIface));
+    }
+
+    @Test
+    public void testPhysicalEthernet() throws Exception {
+        assumeTrue(mEm.isAvailable());
+
+        // Get an interface to use.
+        final String iface = mTetheredInterfaceRequester.getInterface();
+
+        // Enable Ethernet tethering and check that it starts.
+        mTetheringEventCallback = enableEthernetTethering(iface);
+
+        // There is nothing more we can do on a physical interface without connecting an actual
+        // client, which is not possible in this test.
+    }
+
+    private static final class MyTetheringEventCallback implements TetheringEventCallback {
+        private final TetheringManager mTm;
+        private final CountDownLatch mTetheringStartedLatch = new CountDownLatch(1);
+        private final CountDownLatch mTetheringStoppedLatch = new CountDownLatch(1);
+        private final CountDownLatch mClientConnectedLatch = new CountDownLatch(1);
+        private final String mIface;
+
+        private volatile boolean mInterfaceWasTethered = false;
+        private volatile boolean mUnregistered = false;
+        private volatile Collection<TetheredClient> mClients = null;
+
+        MyTetheringEventCallback(TetheringManager tm, String iface) {
+            mTm = tm;
+            mIface = iface;
+        }
+
+        public void unregister() {
+            mTm.unregisterTetheringEventCallback(this);
+            mUnregistered = true;
+        }
+
+        @Override
+        public void onTetheredInterfacesChanged(List<String> interfaces) {
+            // Ignore stale callbacks registered by previous test cases.
+            if (mUnregistered) return;
+
+            final boolean wasTethered = mTetheringStartedLatch.getCount() == 0;
+            if (!mInterfaceWasTethered && (mIface == null || interfaces.contains(mIface))) {
+                // This interface is being tethered for the first time.
+                Log.d(TAG, "Tethering started: " + interfaces);
+                mInterfaceWasTethered = true;
+                mTetheringStartedLatch.countDown();
+            } else if (mInterfaceWasTethered && !interfaces.contains(mIface)) {
+                Log.d(TAG, "Tethering stopped: " + interfaces);
+                mTetheringStoppedLatch.countDown();
+            }
+        }
+
+        public void awaitInterfaceTethered() throws Exception {
+            assertTrue("Ethernet not tethered after " + TIMEOUT_MS + "ms",
+                    mTetheringStartedLatch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
+        }
+
+        public void awaitInterfaceUntethered() throws Exception {
+            // Don't block teardown if the interface was never tethered.
+            // This is racy because the interface might become tethered right after this check, but
+            // that can only happen in tearDown if startTethering timed out, which likely means
+            // the test has already failed.
+            if (!mInterfaceWasTethered) return;
+
+            assertTrue(mIface + " not untethered after " + TIMEOUT_MS + "ms",
+                    mTetheringStoppedLatch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
+        }
+
+        @Override
+        public void onError(String ifName, int error) {
+            // Ignore stale callbacks registered by previous test cases.
+            if (mUnregistered) return;
+
+            fail("TetheringEventCallback got error:" + error + " on iface " + ifName);
+        }
+
+        @Override
+        public void onClientsChanged(Collection<TetheredClient> clients) {
+            // Ignore stale callbacks registered by previous test cases.
+            if (mUnregistered) return;
+
+            Log.d(TAG, "Got clients changed: " + clients);
+            mClients = clients;
+            if (clients.size() > 0) {
+                mClientConnectedLatch.countDown();
+            }
+        }
+
+        public Collection<TetheredClient> awaitClientConnected() throws Exception {
+            assertTrue("Did not receive client connected callback after " + TIMEOUT_MS + "ms",
+                    mClientConnectedLatch.await(TIMEOUT_MS, TimeUnit.MILLISECONDS));
+            return mClients;
+        }
+    }
+
+    private MyTetheringEventCallback enableEthernetTethering(String iface) throws Exception {
+        MyTetheringEventCallback callback = new MyTetheringEventCallback(mTm, iface);
+        mTm.registerTetheringEventCallback(mHandler::post, callback);
+
+        StartTetheringCallback startTetheringCallback = new StartTetheringCallback() {
+            @Override
+            public void onTetheringFailed(int resultCode) {
+                fail("Unexpectedly got onTetheringFailed");
+            }
+        };
+        Log.d(TAG, "Starting Ethernet tethering");
+        mTm.startTethering(
+                new TetheringRequest.Builder(TetheringManager.TETHERING_ETHERNET).build(),
+                mHandler::post /* executor */,  startTetheringCallback);
+        callback.awaitInterfaceTethered();
+        return callback;
+    }
+
+    private int getMTU(TestNetworkInterface iface) throws SocketException {
+        NetworkInterface nif = NetworkInterface.getByName(iface.getInterfaceName());
+        assertNotNull("Can't get NetworkInterface object for " + iface.getInterfaceName(), nif);
+        return nif.getMTU();
+    }
+
+    private void checkVirtualEthernet(TestNetworkInterface iface, int mtu) throws Exception {
+        FileDescriptor fd = iface.getFileDescriptor().getFileDescriptor();
+        mTapPacketReader = new TapPacketReader(mHandler, fd, mtu);
+        mHandler.post(() -> mTapPacketReader.start());
+        HandlerUtilsKt.waitForIdle(mHandler, TIMEOUT_MS);
+
+        mTetheringEventCallback = enableEthernetTethering(iface.getInterfaceName());
+        checkTetheredClientCallbacks(fd);
+    }
+
+    private void checkTetheredClientCallbacks(FileDescriptor fd) throws Exception {
+        // Create a fake client.
+        byte[] clientMacAddr = new byte[6];
+        new Random().nextBytes(clientMacAddr);
+
+        // We have to retransmit DHCP requests because IpServer declares itself to be ready before
+        // its DhcpServer is actually started. TODO: fix this race and remove this loop.
+        DhcpPacket offerPacket = null;
+        for (int i = 0; i < DHCP_DISCOVER_ATTEMPTS; i++) {
+            Log.d(TAG, "Sending DHCP discover");
+            sendDhcpDiscover(fd, clientMacAddr);
+            offerPacket = getNextDhcpPacket();
+            if (offerPacket instanceof DhcpOfferPacket) break;
+        }
+        assertTrue("No DHCPOFFER received on interface within timeout",
+                offerPacket instanceof DhcpOfferPacket);
+
+        sendDhcpRequest(fd, offerPacket, clientMacAddr);
+        DhcpPacket ackPacket = getNextDhcpPacket();
+        assertTrue("No DHCPACK received on interface within timeout",
+                ackPacket instanceof DhcpAckPacket);
+
+        final Collection<TetheredClient> clients = mTetheringEventCallback.awaitClientConnected();
+        assertEquals(1, clients.size());
+        final TetheredClient client = clients.iterator().next();
+
+        // Check the MAC address.
+        assertEquals(MacAddress.fromBytes(clientMacAddr), client.getMacAddress());
+        assertEquals(TetheringManager.TETHERING_ETHERNET, client.getTetheringType());
+
+        // Check the hostname.
+        assertEquals(1, client.getAddresses().size());
+        TetheredClient.AddressInfo info = client.getAddresses().get(0);
+        assertEquals(DHCP_HOSTNAME, info.getHostname());
+
+        // Check the address is the one that was handed out in the DHCP ACK.
+        DhcpResults dhcpResults = offerPacket.toDhcpResults();
+        assertLinkAddressMatches(dhcpResults.ipAddress, info.getAddress());
+
+        // Check that the lifetime is correct +/- 10s.
+        final long now = SystemClock.elapsedRealtime();
+        final long actualLeaseDuration = (info.getAddress().getExpirationTime() - now) / 1000;
+        final String msg = String.format("IP address should have lifetime of %d, got %d",
+                dhcpResults.leaseDuration, actualLeaseDuration);
+        assertTrue(msg, Math.abs(dhcpResults.leaseDuration - actualLeaseDuration) < 10);
+    }
+
+    private DhcpPacket getNextDhcpPacket() throws ParseException {
+        byte[] packet;
+        while ((packet = mTapPacketReader.popPacket(PACKET_READ_TIMEOUT_MS)) != null) {
+            try {
+                return DhcpPacket.decodeFullPacket(packet, packet.length, DhcpPacket.ENCAP_L2);
+            } catch (DhcpPacket.ParseException e) {
+                // Not a DHCP packet. Continue.
+            }
+        }
+        return null;
+    }
+
+    private static final class TetheredInterfaceRequester implements TetheredInterfaceCallback {
+        private final CountDownLatch mInterfaceAvailableLatch = new CountDownLatch(1);
+        private final Handler mHandler;
+        private final EthernetManager mEm;
+
+        private TetheredInterfaceRequest mRequest;
+        private final CompletableFuture<String> mFuture = new CompletableFuture<>();
+
+        TetheredInterfaceRequester(Handler handler, EthernetManager em) {
+            mHandler = handler;
+            mEm = em;
+        }
+
+        @Override
+        public void onAvailable(String iface) {
+            Log.d(TAG, "Ethernet interface available: " + iface);
+            mFuture.complete(iface);
+        }
+
+        @Override
+        public void onUnavailable() {
+            mFuture.completeExceptionally(new IllegalStateException("onUnavailable received"));
+        }
+
+        public CompletableFuture<String> requestInterface() {
+            assertNull("BUG: more than one tethered interface request", mRequest);
+            Log.d(TAG, "Requesting tethered interface");
+            mRequest = mEm.requestTetheredInterface(mHandler::post, this);
+            return mFuture;
+        }
+
+        public String getInterface() throws Exception {
+            return requestInterface().get(TIMEOUT_MS, TimeUnit.MILLISECONDS);
+        }
+
+        public void release() {
+            if (mRequest != null) {
+                mFuture.obtrudeException(new IllegalStateException("Request already released"));
+                mRequest.release();
+                mRequest = null;
+            }
+        }
+    }
+
+    private void sendDhcpDiscover(FileDescriptor fd, byte[] macAddress) throws Exception {
+        ByteBuffer packet = DhcpPacket.buildDiscoverPacket(DhcpPacket.ENCAP_L2,
+                new Random().nextInt() /* transactionId */, (short) 0 /* secs */,
+                macAddress,  false /* unicast */, DHCP_REQUESTED_PARAMS,
+                false /* rapid commit */,  DHCP_HOSTNAME);
+        sendPacket(fd, packet);
+    }
+
+    private void sendDhcpRequest(FileDescriptor fd, DhcpPacket offerPacket, byte[] macAddress)
+            throws Exception {
+        DhcpResults results = offerPacket.toDhcpResults();
+        Inet4Address clientIp = (Inet4Address) results.ipAddress.getAddress();
+        Inet4Address serverIdentifier = results.serverAddress;
+        ByteBuffer packet = DhcpPacket.buildRequestPacket(DhcpPacket.ENCAP_L2,
+                0 /* transactionId */, (short) 0 /* secs */, DhcpPacket.INADDR_ANY /* clientIp */,
+                false /* broadcast */, macAddress, clientIp /* requestedIpAddress */,
+                serverIdentifier, DHCP_REQUESTED_PARAMS, DHCP_HOSTNAME);
+        sendPacket(fd, packet);
+    }
+
+    private void sendPacket(FileDescriptor fd, ByteBuffer packet) throws Exception {
+        assertNotNull("Only tests on virtual interfaces can send packets", fd);
+        Os.write(fd, packet);
+    }
+
+    public void assertLinkAddressMatches(LinkAddress l1, LinkAddress l2) {
+        // Check all fields except the deprecation and expiry times.
+        String msg = String.format("LinkAddresses do not match. expected: %s actual: %s", l1, l2);
+        assertTrue(msg, l1.isSameAddressAs(l2));
+        assertEquals("LinkAddress flags do not match", l1.getFlags(), l2.getFlags());
+        assertEquals("LinkAddress scope does not match", l1.getScope(), l2.getScope());
+    }
+
+    private TestNetworkInterface createTestInterface() throws Exception {
+        TestNetworkManager tnm = mContext.getSystemService(TestNetworkManager.class);
+        TestNetworkInterface iface = tnm.createTapInterface();
+        Log.d(TAG, "Created test interface " + iface.getInterfaceName());
+        assertNotNull(NetworkInterface.getByName(iface.getInterfaceName()));
+        return iface;
+    }
+
+    private void maybeDeleteTestInterface() throws Exception {
+        if (mTestIface != null) {
+            mTestIface.getFileDescriptor().close();
+            Log.d(TAG, "Deleted test interface " + mTestIface.getInterfaceName());
+            mTestIface = null;
+        }
+    }
+}
diff --git a/Tethering/tests/unit/src/android/net/dhcp/DhcpServingParamsParcelExtTest.java b/Tethering/tests/unit/src/android/net/dhcp/DhcpServingParamsParcelExtTest.java
index e8add98..f8eb147 100644
--- a/Tethering/tests/unit/src/android/net/dhcp/DhcpServingParamsParcelExtTest.java
+++ b/Tethering/tests/unit/src/android/net/dhcp/DhcpServingParamsParcelExtTest.java
@@ -42,7 +42,9 @@
 @SmallTest
 public class DhcpServingParamsParcelExtTest {
     private static final Inet4Address TEST_ADDRESS = inet4Addr("192.168.0.123");
+    private static final Inet4Address TEST_CLIENT_ADDRESS = inet4Addr("192.168.0.42");
     private static final int TEST_ADDRESS_PARCELED = 0xc0a8007b;
+    private static final int TEST_CLIENT_ADDRESS_PARCELED = 0xc0a8002a;
     private static final int TEST_PREFIX_LENGTH = 17;
     private static final int TEST_LEASE_TIME_SECS = 120;
     private static final int TEST_MTU = 1000;
@@ -105,6 +107,12 @@
         assertFalse(mParcel.metered);
     }
 
+    @Test
+    public void testSetClientAddr() {
+        mParcel.setSingleClientAddr(TEST_CLIENT_ADDRESS);
+        assertEquals(TEST_CLIENT_ADDRESS_PARCELED, mParcel.clientAddr);
+    }
+
     private static Inet4Address inet4Addr(String addr) {
         return (Inet4Address) parseNumericAddress(addr);
     }
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 0980514..a418c4a 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
@@ -38,6 +38,7 @@
 import static android.net.TetheringManager.TETHER_HARDWARE_OFFLOAD_STARTED;
 import static android.net.TetheringManager.TETHER_HARDWARE_OFFLOAD_STOPPED;
 import static android.net.dhcp.IDhcpServer.STATUS_SUCCESS;
+import static android.net.shared.Inet4AddressUtils.intToInet4AddressHTH;
 import static android.net.wifi.WifiManager.EXTRA_WIFI_AP_INTERFACE_NAME;
 import static android.net.wifi.WifiManager.EXTRA_WIFI_AP_MODE;
 import static android.net.wifi.WifiManager.EXTRA_WIFI_AP_STATE;
@@ -484,6 +485,7 @@
         mServiceContext.registerReceiver(mBroadcastReceiver,
                 new IntentFilter(ACTION_TETHER_STATE_CHANGED));
         mTethering = makeTethering();
+        mTethering.startStateMachineUpdaters();
         verify(mStatsManager, times(1)).registerNetworkStatsProvider(anyString(), any());
         verify(mNetd).registerUnsolicitedEventListener(any());
         final ArgumentCaptor<PhoneStateListener> phoneListenerCaptor =
@@ -1653,10 +1655,13 @@
     }
 
     @Test
-    public void testRequestStaticServerIp() throws Exception {
-        final LinkAddress serverLinkAddr = new LinkAddress("192.168.20.1/24");
-        final LinkAddress clientLinkAddr = new LinkAddress("192.168.20.42/24");
-        final String serverAddr = "192.168.20.1";
+    public void testRequestStaticIp() throws Exception {
+        final LinkAddress serverLinkAddr = new LinkAddress("192.168.0.123/24");
+        final LinkAddress clientLinkAddr = new LinkAddress("192.168.0.42/24");
+        final String serverAddr = "192.168.0.123";
+        final int clientAddrParceled = 0xc0a8002a;
+        final ArgumentCaptor<DhcpServingParamsParcel> dhcpParamsCaptor =
+                ArgumentCaptor.forClass(DhcpServingParamsParcel.class);
         mTethering.startTethering(createTetheringRequestParcel(TETHERING_USB,
                   serverLinkAddr, clientLinkAddr), null);
         mLooper.dispatchAll();
@@ -1665,8 +1670,12 @@
         sendUsbBroadcast(true, true, true, TETHERING_USB);
         mLooper.dispatchAll();
         verify(mNetd).interfaceSetCfg(argThat(cfg -> serverAddr.equals(cfg.ipv4Addr)));
-
-        // TODO: test static client address.
+        verify(mIpServerDependencies, times(1)).makeDhcpServer(any(), dhcpParamsCaptor.capture(),
+                any());
+        final DhcpServingParamsParcel params = dhcpParamsCaptor.getValue();
+        assertEquals(serverAddr, intToInet4AddressHTH(params.serverAddr).getHostAddress());
+        assertEquals(24, params.serverAddrPrefixLength);
+        assertEquals(clientAddrParceled, params.clientAddr);
     }
 
     // TODO: Test that a request for hotspot mode doesn't interfere with an