diff --git a/tests/unit/java/com/android/server/connectivity/VpnTest.java b/tests/unit/java/com/android/server/connectivity/VpnTest.java
index cdfa190..5899fd0 100644
--- a/tests/unit/java/com/android/server/connectivity/VpnTest.java
+++ b/tests/unit/java/com/android/server/connectivity/VpnTest.java
@@ -27,7 +27,9 @@
 import static android.net.ConnectivityManager.NetworkCallback;
 import static android.net.INetd.IF_STATE_DOWN;
 import static android.net.INetd.IF_STATE_UP;
+import static android.net.RouteInfo.RTN_UNREACHABLE;
 import static android.net.VpnManager.TYPE_VPN_PLATFORM;
+import static android.net.ipsec.ike.IkeSessionConfiguration.EXTENSION_TYPE_MOBIKE;
 import static android.os.Build.VERSION_CODES.S_V2;
 import static android.os.UserHandle.PER_USER_RANGE;
 
@@ -59,6 +61,7 @@
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.reset;
+import static org.mockito.Mockito.spy;
 import static org.mockito.Mockito.timeout;
 import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
@@ -83,7 +86,9 @@
 import android.net.InetAddresses;
 import android.net.InterfaceConfigurationParcel;
 import android.net.IpPrefix;
+import android.net.IpSecConfig;
 import android.net.IpSecManager;
+import android.net.IpSecTransform;
 import android.net.IpSecTunnelInterfaceResponse;
 import android.net.LinkAddress;
 import android.net.LinkProperties;
@@ -100,7 +105,12 @@
 import android.net.VpnProfileState;
 import android.net.VpnService;
 import android.net.VpnTransportInfo;
+import android.net.ipsec.ike.ChildSessionCallback;
+import android.net.ipsec.ike.ChildSessionConfiguration;
 import android.net.ipsec.ike.IkeSessionCallback;
+import android.net.ipsec.ike.IkeSessionConfiguration;
+import android.net.ipsec.ike.IkeSessionConnectionInfo;
+import android.net.ipsec.ike.IkeTrafficSelector;
 import android.net.ipsec.ike.exceptions.IkeException;
 import android.net.ipsec.ike.exceptions.IkeNetworkLostException;
 import android.net.ipsec.ike.exceptions.IkeNonProtocolException;
@@ -121,6 +131,7 @@
 import android.security.Credentials;
 import android.util.ArrayMap;
 import android.util.ArraySet;
+import android.util.Pair;
 import android.util.Range;
 
 import androidx.test.filters.SmallTest;
@@ -155,6 +166,7 @@
 import java.io.FileWriter;
 import java.io.IOException;
 import java.net.Inet4Address;
+import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.net.UnknownHostException;
 import java.util.ArrayList;
@@ -165,6 +177,7 @@
 import java.util.Map;
 import java.util.Set;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Stream;
 
@@ -198,11 +211,37 @@
     static final Network EGRESS_NETWORK = new Network(101);
     static final String EGRESS_IFACE = "wlan0";
     static final String TEST_VPN_PKG = "com.testvpn.vpn";
+    private static final String TEST_VPN_CLIENT = "2.4.6.8";
     private static final String TEST_VPN_SERVER = "1.2.3.4";
     private static final String TEST_VPN_IDENTITY = "identity";
     private static final byte[] TEST_VPN_PSK = "psk".getBytes();
 
+    private static final int IP4_PREFIX_LEN = 32;
+    private static final int MIN_PORT = 0;
+    private static final int MAX_PORT = 65535;
+
+    private static final InetAddress TEST_VPN_CLIENT_IP =
+            InetAddresses.parseNumericAddress(TEST_VPN_CLIENT);
+    private static final InetAddress TEST_VPN_SERVER_IP =
+            InetAddresses.parseNumericAddress(TEST_VPN_SERVER);
+    private static final InetAddress TEST_VPN_CLIENT_IP_2 =
+            InetAddresses.parseNumericAddress("192.0.2.200");
+    private static final InetAddress TEST_VPN_SERVER_IP_2 =
+            InetAddresses.parseNumericAddress("192.0.2.201");
+    private static final InetAddress TEST_VPN_INTERNAL_IP =
+            InetAddresses.parseNumericAddress("198.51.100.10");
+    private static final InetAddress TEST_VPN_INTERNAL_DNS =
+            InetAddresses.parseNumericAddress("8.8.8.8");
+
+    private static final IkeTrafficSelector IN_TS =
+            new IkeTrafficSelector(MIN_PORT, MAX_PORT, TEST_VPN_INTERNAL_IP, TEST_VPN_INTERNAL_IP);
+    private static final IkeTrafficSelector OUT_TS =
+            new IkeTrafficSelector(MIN_PORT, MAX_PORT,
+                    InetAddresses.parseNumericAddress("0.0.0.0"),
+                    InetAddresses.parseNumericAddress("255.255.255.255"));
+
     private static final Network TEST_NETWORK = new Network(Integer.MAX_VALUE);
+    private static final Network TEST_NETWORK_2 = new Network(Integer.MAX_VALUE - 1);
     private static final String TEST_IFACE_NAME = "TEST_IFACE";
     private static final int TEST_TUNNEL_RESOURCE_ID = 0x2345;
     private static final long TEST_TIMEOUT_MS = 500L;
@@ -234,7 +273,9 @@
     @Mock private AppOpsManager mAppOps;
     @Mock private NotificationManager mNotificationManager;
     @Mock private Vpn.SystemServices mSystemServices;
+    @Mock private Vpn.IkeSessionWrapper mIkeSessionWrapper;
     @Mock private Vpn.Ikev2SessionCreator mIkev2SessionCreator;
+    @Mock private NetworkAgent mMockNetworkAgent;
     @Mock private ConnectivityManager mConnectivityManager;
     @Mock private IpSecService mIpSecService;
     @Mock private VpnProfileStore mVpnProfileStore;
@@ -243,6 +284,8 @@
 
     private IpSecManager mIpSecManager;
 
+    private TestDeps mTestDeps;
+
     public VpnTest() throws Exception {
         // Build an actual VPN profile that is capable of being converted to and from an
         // Ikev2VpnProfile
@@ -257,6 +300,7 @@
         MockitoAnnotations.initMocks(this);
 
         mIpSecManager = new IpSecManager(mContext, mIpSecService);
+        mTestDeps = spy(new TestDeps());
 
         when(mContext.getPackageManager()).thenReturn(mPackageManager);
         setMockedPackages(mPackages);
@@ -297,6 +341,14 @@
         // itself, so set the default value of Context#checkCallingOrSelfPermission to
         // PERMISSION_DENIED.
         doReturn(PERMISSION_DENIED).when(mContext).checkCallingOrSelfPermission(any());
+
+        resetIkev2SessionCreator(mIkeSessionWrapper);
+    }
+
+    private void resetIkev2SessionCreator(Vpn.IkeSessionWrapper ikeSession) {
+        reset(mIkev2SessionCreator);
+        when(mIkev2SessionCreator.createIkeSession(any(), any(), any(), any(), any(), any()))
+                .thenReturn(ikeSession);
     }
 
     @After
@@ -1320,6 +1372,10 @@
         final ArgumentCaptor<IkeSessionCallback> captor =
                 ArgumentCaptor.forClass(IkeSessionCallback.class);
 
+        // This test depends on a real ScheduledThreadPoolExecutor
+        doReturn(new ScheduledThreadPoolExecutor(1)).when(mTestDeps)
+                .newScheduledThreadPoolExecutor();
+
         final Vpn vpn = createVpnAndSetupUidChecks(AppOpsManager.OPSTR_ACTIVATE_PLATFORM_VPN);
         when(mVpnProfileStore.get(vpn.getProfileNameForPackage(TEST_VPN_PKG)))
                 .thenReturn(mVpnProfile.encode());
@@ -1491,14 +1547,217 @@
         return vpn;
     }
 
+    private IkeSessionConnectionInfo createIkeConnectInfo() {
+        return new IkeSessionConnectionInfo(TEST_VPN_CLIENT_IP, TEST_VPN_SERVER_IP, TEST_NETWORK);
+    }
+
+    private IkeSessionConnectionInfo createIkeConnectInfo_2() {
+        return new IkeSessionConnectionInfo(
+                TEST_VPN_CLIENT_IP_2, TEST_VPN_SERVER_IP_2, TEST_NETWORK_2);
+    }
+
+    private IkeSessionConfiguration createIkeConfig(
+            IkeSessionConnectionInfo ikeConnectInfo, boolean isMobikeEnabled) {
+        final IkeSessionConfiguration.Builder builder =
+                new IkeSessionConfiguration.Builder(ikeConnectInfo);
+
+        if (isMobikeEnabled) {
+            builder.addIkeExtension(EXTENSION_TYPE_MOBIKE);
+        }
+
+        return builder.build();
+    }
+
+    private ChildSessionConfiguration createChildConfig() {
+        return new ChildSessionConfiguration.Builder(Arrays.asList(IN_TS), Arrays.asList(OUT_TS))
+                .addInternalAddress(new LinkAddress(TEST_VPN_INTERNAL_IP, IP4_PREFIX_LEN))
+                .addInternalDnsServer(TEST_VPN_INTERNAL_DNS)
+                .build();
+    }
+
+    private IpSecTransform createIpSecTransform() {
+        return new IpSecTransform(mContext, new IpSecConfig());
+    }
+
+    private void verifyApplyTunnelModeTransforms(int expectedTimes) throws Exception {
+        verify(mIpSecService, times(expectedTimes)).applyTunnelModeTransform(
+                eq(TEST_TUNNEL_RESOURCE_ID), eq(IpSecManager.DIRECTION_IN),
+                anyInt(), anyString());
+        verify(mIpSecService, times(expectedTimes)).applyTunnelModeTransform(
+                eq(TEST_TUNNEL_RESOURCE_ID), eq(IpSecManager.DIRECTION_OUT),
+                anyInt(), anyString());
+    }
+
+    private Pair<IkeSessionCallback, ChildSessionCallback> verifyCreateIkeAndCaptureCbs()
+            throws Exception {
+        final ArgumentCaptor<IkeSessionCallback> ikeCbCaptor =
+                ArgumentCaptor.forClass(IkeSessionCallback.class);
+        final ArgumentCaptor<ChildSessionCallback> childCbCaptor =
+                ArgumentCaptor.forClass(ChildSessionCallback.class);
+
+        verify(mIkev2SessionCreator, timeout(TEST_TIMEOUT_MS)).createIkeSession(
+                any(), any(), any(), any(), ikeCbCaptor.capture(), childCbCaptor.capture());
+
+        return new Pair<>(ikeCbCaptor.getValue(), childCbCaptor.getValue());
+    }
+
+    private static class PlatformVpnSnapshot {
+        public final Vpn vpn;
+        public final NetworkCallback nwCb;
+        public final IkeSessionCallback ikeCb;
+        public final ChildSessionCallback childCb;
+
+        PlatformVpnSnapshot(Vpn vpn, NetworkCallback nwCb,
+                IkeSessionCallback ikeCb, ChildSessionCallback childCb) {
+            this.vpn = vpn;
+            this.nwCb = nwCb;
+            this.ikeCb = ikeCb;
+            this.childCb = childCb;
+        }
+    }
+
+    private PlatformVpnSnapshot verifySetupPlatformVpn(IkeSessionConfiguration ikeConfig)
+            throws Exception {
+        doReturn(mMockNetworkAgent).when(mTestDeps)
+                .newNetworkAgent(
+                        any(), any(), anyString(), any(), any(), any(), any(), any());
+
+        final Vpn vpn = createVpnAndSetupUidChecks(AppOpsManager.OPSTR_ACTIVATE_PLATFORM_VPN);
+        when(mVpnProfileStore.get(vpn.getProfileNameForPackage(TEST_VPN_PKG)))
+                .thenReturn(mVpnProfile.encode());
+
+        vpn.startVpnProfile(TEST_VPN_PKG);
+        final NetworkCallback nwCb = triggerOnAvailableAndGetCallback();
+
+        // Mock the setup procedure by firing callbacks
+        final Pair<IkeSessionCallback, ChildSessionCallback> cbPair =
+                verifyCreateIkeAndCaptureCbs();
+        final IkeSessionCallback ikeCb = cbPair.first;
+        final ChildSessionCallback childCb = cbPair.second;
+
+        ikeCb.onOpened(ikeConfig);
+        childCb.onIpSecTransformCreated(createIpSecTransform(), IpSecManager.DIRECTION_IN);
+        childCb.onIpSecTransformCreated(createIpSecTransform(), IpSecManager.DIRECTION_OUT);
+        childCb.onOpened(createChildConfig());
+
+        // Verification VPN setup
+        verifyApplyTunnelModeTransforms(1);
+
+        ArgumentCaptor<LinkProperties> lpCaptor = ArgumentCaptor.forClass(LinkProperties.class);
+        ArgumentCaptor<NetworkCapabilities> ncCaptor =
+                ArgumentCaptor.forClass(NetworkCapabilities.class);
+        verify(mTestDeps).newNetworkAgent(
+                any(), any(), anyString(), ncCaptor.capture(), lpCaptor.capture(),
+                any(), any(), any());
+
+        // Check LinkProperties
+        final LinkProperties lp = lpCaptor.getValue();
+        final List<RouteInfo> expectedRoutes = Arrays.asList(
+                new RouteInfo(new IpPrefix(Inet4Address.ANY, 0), null /*gateway*/,
+                        TEST_IFACE_NAME, RouteInfo.RTN_UNICAST),
+                new RouteInfo(new IpPrefix(Inet6Address.ANY, 0), null /*gateway*/,
+                        TEST_IFACE_NAME, RTN_UNREACHABLE));
+        assertEquals(expectedRoutes, lp.getRoutes());
+
+        // Check internal addresses
+        final List<LinkAddress> expectedAddresses =
+                Arrays.asList(new LinkAddress(TEST_VPN_INTERNAL_IP, IP4_PREFIX_LEN));
+        assertEquals(expectedAddresses, lp.getLinkAddresses());
+
+        // Check internal DNS
+        assertEquals(Arrays.asList(TEST_VPN_INTERNAL_DNS), lp.getDnsServers());
+
+        // Check NetworkCapabilities
+        assertEquals(Arrays.asList(TEST_NETWORK), ncCaptor.getValue().getUnderlyingNetworks());
+
+        return new PlatformVpnSnapshot(vpn, nwCb, ikeCb, childCb);
+    }
+
     @Test
     public void testStartPlatformVpn() throws Exception {
-        startLegacyVpn(createVpn(primaryUser.id), mVpnProfile);
-        // TODO: Test the Ikev2VpnRunner started up properly. Relies on utility methods added in
-        // a subsequent patch.
+        final PlatformVpnSnapshot vpnSnapShot = verifySetupPlatformVpn(
+                createIkeConfig(createIkeConnectInfo(), true /* isMobikeEnabled */));
+        vpnSnapShot.vpn.mVpnRunner.exitVpnRunner();
     }
 
     @Test
+    public void testStartPlatformVpnMobility_mobikeEnabled() throws Exception {
+        final PlatformVpnSnapshot vpnSnapShot = verifySetupPlatformVpn(
+                createIkeConfig(createIkeConnectInfo(), true /* isMobikeEnabled */));
+
+        // Mock network switch
+        vpnSnapShot.nwCb.onLost(TEST_NETWORK);
+        vpnSnapShot.nwCb.onAvailable(TEST_NETWORK_2);
+
+        // Verify MOBIKE is triggered
+        verify(mIkeSessionWrapper).setNetwork(TEST_NETWORK_2);
+
+        // Mock the MOBIKE procedure
+        vpnSnapShot.ikeCb.onIkeSessionConnectionInfoChanged(createIkeConnectInfo_2());
+        vpnSnapShot.childCb.onIpSecTransformsMigrated(
+                createIpSecTransform(), createIpSecTransform());
+
+        verify(mIpSecService).setNetworkForTunnelInterface(
+                eq(TEST_TUNNEL_RESOURCE_ID), eq(TEST_NETWORK_2), anyString());
+
+        // Expect 2 times: one for initial setup and one for MOBIKE
+        verifyApplyTunnelModeTransforms(2);
+
+        // Verify mNetworkCapabilities and mNetworkAgent are updated
+        assertEquals(
+                Collections.singletonList(TEST_NETWORK_2),
+                vpnSnapShot.vpn.mNetworkCapabilities.getUnderlyingNetworks());
+        verify(mMockNetworkAgent)
+                .setUnderlyingNetworks(Collections.singletonList(TEST_NETWORK_2));
+
+        vpnSnapShot.vpn.mVpnRunner.exitVpnRunner();
+    }
+
+    @Test
+    public void testStartPlatformVpnReestablishes_mobikeDisabled() throws Exception {
+        final PlatformVpnSnapshot vpnSnapShot = verifySetupPlatformVpn(
+                createIkeConfig(createIkeConnectInfo(), false /* isMobikeEnabled */));
+
+        // Forget the first IKE creation to be prepared to capture callbacks of the second
+        // IKE session
+        resetIkev2SessionCreator(mock(Vpn.IkeSessionWrapper.class));
+
+        // Mock network switch
+        vpnSnapShot.nwCb.onLost(TEST_NETWORK);
+        vpnSnapShot.nwCb.onAvailable(TEST_NETWORK_2);
+
+        // Verify the old IKE Session is killed
+        verify(mIkeSessionWrapper).kill();
+
+        // Capture callbacks of the new IKE Session
+        final Pair<IkeSessionCallback, ChildSessionCallback> cbPair =
+                verifyCreateIkeAndCaptureCbs();
+        final IkeSessionCallback ikeCb = cbPair.first;
+        final ChildSessionCallback childCb = cbPair.second;
+
+        // Mock the IKE Session setup
+        ikeCb.onOpened(createIkeConfig(createIkeConnectInfo_2(), false /* isMobikeEnabled */));
+
+        childCb.onIpSecTransformCreated(createIpSecTransform(), IpSecManager.DIRECTION_IN);
+        childCb.onIpSecTransformCreated(createIpSecTransform(), IpSecManager.DIRECTION_OUT);
+        childCb.onOpened(createChildConfig());
+
+        // Expect 2 times since there have been two Session setups
+        verifyApplyTunnelModeTransforms(2);
+
+        // Verify mNetworkCapabilities and mNetworkAgent are updated
+        assertEquals(
+                Collections.singletonList(TEST_NETWORK_2),
+                vpnSnapShot.vpn.mNetworkCapabilities.getUnderlyingNetworks());
+        verify(mMockNetworkAgent)
+                .setUnderlyingNetworks(Collections.singletonList(TEST_NETWORK_2));
+
+        vpnSnapShot.vpn.mVpnRunner.exitVpnRunner();
+    }
+
+    // TODO: Add a test for network loss without mobility
+
+    @Test
     public void testStartRacoonNumericAddress() throws Exception {
         startRacoon("1.2.3.4", "1.2.3.4");
     }
@@ -1578,7 +1837,8 @@
         }
     }
 
-    private final class TestDeps extends Vpn.Dependencies {
+    // Make it public and un-final so as to spy it
+    public class TestDeps extends Vpn.Dependencies {
         public final CompletableFuture<String[]> racoonArgs = new CompletableFuture();
         public final CompletableFuture<String[]> mtpdArgs = new CompletableFuture();
         public final File mStateFile;
@@ -1713,10 +1973,25 @@
             return mDeviceIdleInternal;
         }
 
+        @Override
         public long getNextRetryDelaySeconds(int retryCount) {
             // Simply return retryCount as the delay seconds for retrying.
             return retryCount;
         }
+
+        @Override
+        public ScheduledThreadPoolExecutor newScheduledThreadPoolExecutor() {
+            final ScheduledThreadPoolExecutor mockExecutor =
+                    mock(ScheduledThreadPoolExecutor.class);
+            doAnswer(
+                    (invocation) -> {
+                        ((Runnable) invocation.getArgument(0)).run();
+                        return null;
+                    })
+                .when(mockExecutor)
+                .execute(any());
+            return mockExecutor;
+        }
     }
 
     /**
@@ -1728,7 +2003,7 @@
         when(mContext.createContextAsUser(eq(UserHandle.of(userId)), anyInt()))
                 .thenReturn(asUserContext);
         final TestLooper testLooper = new TestLooper();
-        final Vpn vpn = new Vpn(testLooper.getLooper(), mContext, new TestDeps(), mNetService,
+        final Vpn vpn = new Vpn(testLooper.getLooper(), mContext, mTestDeps, mNetService,
                 mNetd, userId, mVpnProfileStore, mSystemServices, mIkev2SessionCreator);
         verify(mConnectivityManager, times(1)).registerNetworkProvider(argThat(
                 provider -> provider.getName().contains("VpnNetworkProvider")