diff --git a/framework/Android.bp b/framework/Android.bp
index 657d5a3..3553c1f 100644
--- a/framework/Android.bp
+++ b/framework/Android.bp
@@ -128,6 +128,7 @@
     srcs: [
         "jni/android_net_NetworkUtils.cpp",
     ],
+    shared_libs: ["libandroid_net"],
     apex_available: [
         "//apex_available:platform",
         "com.android.tethering",
@@ -140,6 +141,7 @@
     srcs: [
         "jni/onload.cpp",
     ],
+    shared_libs: ["libandroid"],
     static_libs: ["libconnectivityframeworkutils"],
     apex_available: [
         "//apex_available:platform",
diff --git a/framework/jni/android_net_NetworkUtils.cpp b/framework/jni/android_net_NetworkUtils.cpp
index c5b1ff8..c7c0bee 100644
--- a/framework/jni/android_net_NetworkUtils.cpp
+++ b/framework/jni/android_net_NetworkUtils.cpp
@@ -19,6 +19,7 @@
 #include <vector>
 
 #include <android/file_descriptor_jni.h>
+#include <android/multinetwork.h>
 #include <arpa/inet.h>
 #include <linux/filter.h>
 #include <linux/if_arp.h>
@@ -94,14 +95,21 @@
     }
 }
 
-static jboolean android_net_utils_bindProcessToNetwork(JNIEnv *env, jobject thiz, jint netId)
+static jboolean android_net_utils_bindProcessToNetworkHandle(JNIEnv *env, jobject thiz,
+        jlong netHandle)
 {
-    return (jboolean) !setNetworkForProcess(netId);
+    return (jboolean) !android_setprocnetwork(netHandle);
 }
 
-static jint android_net_utils_getBoundNetworkForProcess(JNIEnv *env, jobject thiz)
+static jlong android_net_utils_getBoundNetworkHandleForProcess(JNIEnv *env, jobject thiz)
 {
-    return getNetworkForProcess();
+    net_handle_t network;
+    if (android_getprocnetwork(&network) != 0) {
+        jniThrowExceptionFmt(env, "java/lang/IllegalStateException",
+                "android_getprocnetwork(): %s", strerror(errno));
+        return NETWORK_UNSPECIFIED;
+    }
+    return (jlong) network;
 }
 
 static jboolean android_net_utils_bindProcessToNetworkForHostResolution(JNIEnv *env, jobject thiz,
@@ -255,8 +263,8 @@
 // clang-format off
 static const JNINativeMethod gNetworkUtilMethods[] = {
     /* name, signature, funcPtr */
-    { "bindProcessToNetwork", "(I)Z", (void*) android_net_utils_bindProcessToNetwork },
-    { "getBoundNetworkForProcess", "()I", (void*) android_net_utils_getBoundNetworkForProcess },
+    { "bindProcessToNetworkHandle", "(J)Z", (void*) android_net_utils_bindProcessToNetworkHandle },
+    { "getBoundNetworkHandleForProcess", "()J", (void*) android_net_utils_getBoundNetworkHandleForProcess },
     { "bindProcessToNetworkForHostResolution", "(I)Z", (void*) android_net_utils_bindProcessToNetworkForHostResolution },
     { "bindSocketToNetwork", "(Ljava/io/FileDescriptor;I)I", (void*) android_net_utils_bindSocketToNetwork },
     { "queryUserAccess", "(II)Z", (void*)android_net_utils_queryUserAccess },
diff --git a/framework/src/android/net/NetworkUtils.java b/framework/src/android/net/NetworkUtils.java
index c4bebc0..16ae55f 100644
--- a/framework/src/android/net/NetworkUtils.java
+++ b/framework/src/android/net/NetworkUtils.java
@@ -16,6 +16,8 @@
 
 package android.net;
 
+import static android.net.ConnectivityManager.NETID_UNSET;
+
 import android.compat.annotation.UnsupportedAppUsage;
 import android.os.Build;
 import android.system.ErrnoException;
@@ -55,6 +57,8 @@
      */
     public static native void detachBPFFilter(FileDescriptor fd) throws SocketException;
 
+    private static native boolean bindProcessToNetworkHandle(long netHandle);
+
     /**
      * Binds the current process to the network designated by {@code netId}.  All sockets created
      * in the future (and not explicitly bound via a bound {@link SocketFactory} (see
@@ -63,13 +67,20 @@
      * is by design so an application doesn't accidentally use sockets it thinks are still bound to
      * a particular {@code Network}.  Passing NETID_UNSET clears the binding.
      */
-    public native static boolean bindProcessToNetwork(int netId);
+    public static boolean bindProcessToNetwork(int netId) {
+        return bindProcessToNetworkHandle(new Network(netId).getNetworkHandle());
+    }
+
+    private static native long getBoundNetworkHandleForProcess();
 
     /**
      * Return the netId last passed to {@link #bindProcessToNetwork}, or NETID_UNSET if
      * {@link #unbindProcessToNetwork} has been called since {@link #bindProcessToNetwork}.
      */
-    public native static int getBoundNetworkForProcess();
+    public static int getBoundNetworkForProcess() {
+        final long netHandle = getBoundNetworkHandleForProcess();
+        return netHandle == 0L ? NETID_UNSET : Network.fromNetworkHandle(netHandle).getNetId();
+    }
 
     /**
      * Binds host resolutions performed by this process to the network designated by {@code netId}.
diff --git a/service/Android.bp b/service/Android.bp
index 1330e71..37dd9ff 100644
--- a/service/Android.bp
+++ b/service/Android.bp
@@ -51,22 +51,33 @@
 
 java_library {
     name: "service-connectivity-pre-jarjar",
+    sdk_version: "system_server_current",
     srcs: [
-        ":framework-connectivity-shared-srcs",
         ":connectivity-service-srcs",
+        ":framework-connectivity-shared-srcs",
+        ":services-connectivity-shared-srcs",
+        // TODO: move to net-utils-device-common, enable shrink optimization to avoid extra classes
+        ":net-module-utils-srcs",
     ],
     libs: [
-        "android.net.ipsec.ike",
-        "services.core",
-        "services.net",
+        // TODO (b/183097033) remove once system_server_current includes core_current
+        "stable.core.platform.api.stubs",
+        "android_system_server_stubs_current",
+        "framework-annotations-lib",
+        "framework-connectivity.impl",
+        "framework-tethering.stubs.module_lib",
+        "framework-wifi.stubs.module_lib",
         "unsupportedappusage",
         "ServiceConnectivityResources",
     ],
     static_libs: [
+        "dnsresolver_aidl_interface-V7-java",
         "modules-utils-os",
         "net-utils-device-common",
         "net-utils-framework-common",
         "netd-client",
+        "netlink-client",
+        "networkstack-client",
         "PlatformProperties",
         "service-connectivity-protos",
     ],
@@ -78,6 +89,7 @@
 
 java_library {
     name: "service-connectivity-protos",
+    sdk_version: "system_current",
     proto: {
         type: "nano",
     },
@@ -93,6 +105,7 @@
 
 java_library {
     name: "service-connectivity",
+    sdk_version: "system_server_current",
     installable: true,
     static_libs: [
         "service-connectivity-pre-jarjar",
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index 1985848..fbba189 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -145,7 +145,6 @@
 import android.net.NetworkScore;
 import android.net.NetworkSpecifier;
 import android.net.NetworkStack;
-import android.net.NetworkStackClient;
 import android.net.NetworkState;
 import android.net.NetworkStateSnapshot;
 import android.net.NetworkTestResultParcelable;
@@ -172,13 +171,14 @@
 import android.net.metrics.IpConnectivityLog;
 import android.net.metrics.NetworkEvent;
 import android.net.netlink.InetDiagMessage;
+import android.net.networkstack.ModuleNetworkStackClient;
+import android.net.networkstack.NetworkStackClientBase;
 import android.net.resolv.aidl.DnsHealthEventParcel;
 import android.net.resolv.aidl.IDnsResolverUnsolicitedEventListener;
 import android.net.resolv.aidl.Nat64PrefixEventParcel;
 import android.net.resolv.aidl.PrivateDnsValidationEventParcel;
 import android.net.shared.PrivateDnsConfig;
 import android.net.util.MultinetworkPolicyTracker;
-import android.net.util.NetdService;
 import android.os.BatteryStatsManager;
 import android.os.Binder;
 import android.os.Build;
@@ -1121,10 +1121,10 @@
         }
 
         /**
-         * Get a reference to the NetworkStackClient.
+         * Get a reference to the ModuleNetworkStackClient.
          */
-        public NetworkStackClient getNetworkStack() {
-            return NetworkStackClient.getInstance();
+        public NetworkStackClientBase getNetworkStack() {
+            return ModuleNetworkStackClient.getInstance(null);
         }
 
         /**
@@ -1183,7 +1183,8 @@
 
     public ConnectivityService(Context context) {
         this(context, getDnsResolver(context), new IpConnectivityLog(),
-                NetdService.getInstance(), new Dependencies());
+                INetd.Stub.asInterface((IBinder) context.getSystemService(Context.NETD_SERVICE)),
+                new Dependencies());
     }
 
     @VisibleForTesting
@@ -2904,10 +2905,6 @@
         }
 
         pw.println();
-        pw.println("NetworkStackClient logs:");
-        pw.increaseIndent();
-        NetworkStackClient.getInstance().dump(pw);
-        pw.decreaseIndent();
 
         pw.println();
         pw.println("Permission Monitor:");
diff --git a/services/core/java/com/android/server/TestNetworkService.java b/services/core/java/com/android/server/TestNetworkService.java
index f566277..09873f4 100644
--- a/services/core/java/com/android/server/TestNetworkService.java
+++ b/services/core/java/com/android/server/TestNetworkService.java
@@ -35,7 +35,6 @@
 import android.net.RouteInfo;
 import android.net.TestNetworkInterface;
 import android.net.TestNetworkSpecifier;
-import android.net.util.NetdService;
 import android.os.Binder;
 import android.os.Handler;
 import android.os.HandlerThread;
@@ -86,7 +85,9 @@
         mHandler = new Handler(mHandlerThread.getLooper());
 
         mContext = Objects.requireNonNull(context, "missing Context");
-        mNetd = Objects.requireNonNull(NetdService.getInstance(), "could not get netd instance");
+        mNetd = Objects.requireNonNull(
+                INetd.Stub.asInterface((IBinder) context.getSystemService(Context.NETD_SERVICE)),
+                "could not get netd instance");
         mCm = mContext.getSystemService(ConnectivityManager.class);
         mNetworkProvider = new NetworkProvider(mContext, mHandler.getLooper(),
                 TEST_NETWORK_PROVIDER_NAME);
diff --git a/services/core/java/com/android/server/connectivity/OsCompat.java b/services/core/java/com/android/server/connectivity/OsCompat.java
new file mode 100644
index 0000000..57e3dcd
--- /dev/null
+++ b/services/core/java/com/android/server/connectivity/OsCompat.java
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2021 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 com.android.server.connectivity;
+
+import android.system.ErrnoException;
+import android.system.Os;
+
+import java.io.FileDescriptor;
+
+/**
+ * Compatibility utility for android.system.Os core platform APIs.
+ *
+ * Connectivity has access to such APIs, but they are not part of the module_current stubs yet
+ * (only core_current). Most stable core platform APIs are included manually in the connectivity
+ * build rules, but because Os is also part of the base java SDK that is earlier on the
+ * classpath, the extra core platform APIs are not seen.
+ *
+ * TODO (b/157639992, b/183097033): remove as soon as core_current is part of system_server_current
+ * @hide
+ */
+public class OsCompat {
+    // This value should be correct on all architectures supported by Android, but hardcoding ioctl
+    // numbers should be avoided.
+    /**
+     * @see android.system.OsConstants#TIOCOUTQ
+     */
+    public static final int TIOCOUTQ = 0x5411;
+
+    /**
+     * @see android.system.Os#getsockoptInt(FileDescriptor, int, int)
+     */
+    public static int getsockoptInt(FileDescriptor fd, int level, int option) throws
+            ErrnoException {
+        try {
+            return (int) Os.class.getMethod(
+                    "getsockoptInt", FileDescriptor.class, int.class, int.class)
+                    .invoke(null, fd, level, option);
+        } catch (ReflectiveOperationException e) {
+            if (e.getCause() instanceof ErrnoException) {
+                throw (ErrnoException) e.getCause();
+            }
+            throw new IllegalStateException("Error calling getsockoptInt", e);
+        }
+    }
+
+    /**
+     * @see android.system.Os#ioctlInt(FileDescriptor, int)
+     */
+    public static int ioctlInt(FileDescriptor fd, int cmd) throws
+            ErrnoException {
+        try {
+            return (int) Os.class.getMethod(
+                    "ioctlInt", FileDescriptor.class, int.class).invoke(null, fd, cmd);
+        } catch (ReflectiveOperationException e) {
+            if (e.getCause() instanceof ErrnoException) {
+                throw (ErrnoException) e.getCause();
+            }
+            throw new IllegalStateException("Error calling ioctlInt", e);
+        }
+    }
+}
diff --git a/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java b/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java
index c480594..73f3475 100644
--- a/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java
+++ b/services/core/java/com/android/server/connectivity/TcpKeepaliveController.java
@@ -27,7 +27,8 @@
 import static android.system.OsConstants.IPPROTO_TCP;
 import static android.system.OsConstants.IP_TOS;
 import static android.system.OsConstants.IP_TTL;
-import static android.system.OsConstants.TIOCOUTQ;
+
+import static com.android.server.connectivity.OsCompat.TIOCOUTQ;
 
 import android.annotation.NonNull;
 import android.net.InvalidPacketException;
@@ -175,10 +176,10 @@
             }
             // Query write sequence number from SEND_QUEUE.
             Os.setsockoptInt(fd, IPPROTO_TCP, TCP_REPAIR_QUEUE, TCP_SEND_QUEUE);
-            tcpDetails.seq = Os.getsockoptInt(fd, IPPROTO_TCP, TCP_QUEUE_SEQ);
+            tcpDetails.seq = OsCompat.getsockoptInt(fd, IPPROTO_TCP, TCP_QUEUE_SEQ);
             // Query read sequence number from RECV_QUEUE.
             Os.setsockoptInt(fd, IPPROTO_TCP, TCP_REPAIR_QUEUE, TCP_RECV_QUEUE);
-            tcpDetails.ack = Os.getsockoptInt(fd, IPPROTO_TCP, TCP_QUEUE_SEQ);
+            tcpDetails.ack = OsCompat.getsockoptInt(fd, IPPROTO_TCP, TCP_QUEUE_SEQ);
             // Switch to NO_QUEUE to prevent illegal socket read/write in repair mode.
             Os.setsockoptInt(fd, IPPROTO_TCP, TCP_REPAIR_QUEUE, TCP_NO_QUEUE);
             // Finally, check if socket is still idle. TODO : this check needs to move to
@@ -198,9 +199,9 @@
             tcpDetails.rcvWndScale = trw.rcvWndScale;
             if (tcpDetails.srcAddress.length == 4 /* V4 address length */) {
                 // Query TOS.
-                tcpDetails.tos = Os.getsockoptInt(fd, IPPROTO_IP, IP_TOS);
+                tcpDetails.tos = OsCompat.getsockoptInt(fd, IPPROTO_IP, IP_TOS);
                 // Query TTL.
-                tcpDetails.ttl = Os.getsockoptInt(fd, IPPROTO_IP, IP_TTL);
+                tcpDetails.ttl = OsCompat.getsockoptInt(fd, IPPROTO_IP, IP_TTL);
             }
         } catch (ErrnoException e) {
             Log.e(TAG, "Exception reading TCP state from socket", e);
@@ -305,7 +306,7 @@
 
     private static boolean isReceiveQueueEmpty(FileDescriptor fd)
             throws ErrnoException {
-        final int result = Os.ioctlInt(fd, SIOCINQ);
+        final int result = OsCompat.ioctlInt(fd, SIOCINQ);
         if (result != 0) {
             Log.e(TAG, "Read queue has data");
             return false;
@@ -315,7 +316,7 @@
 
     private static boolean isSendQueueEmpty(FileDescriptor fd)
             throws ErrnoException {
-        final int result = Os.ioctlInt(fd, SIOCOUTQ);
+        final int result = OsCompat.ioctlInt(fd, SIOCOUTQ);
         if (result != 0) {
             Log.e(TAG, "Write queue has data");
             return false;
diff --git a/tests/net/integration/src/android/net/TestNetworkStackClient.kt b/tests/net/integration/src/android/net/TestNetworkStackClient.kt
index 01eb514..61ef5bd 100644
--- a/tests/net/integration/src/android/net/TestNetworkStackClient.kt
+++ b/tests/net/integration/src/android/net/TestNetworkStackClient.kt
@@ -19,6 +19,7 @@
 import android.content.ComponentName
 import android.content.Context
 import android.content.Intent
+import android.net.networkstack.NetworkStackClientBase
 import android.os.IBinder
 import com.android.server.net.integrationtests.TestNetworkStackService
 import org.mockito.Mockito.any
@@ -29,28 +30,22 @@
 
 const val TEST_ACTION_SUFFIX = ".Test"
 
-class TestNetworkStackClient(context: Context) : NetworkStackClient(TestDependencies(context)) {
+class TestNetworkStackClient(private val context: Context) : NetworkStackClientBase() {
     // TODO: consider switching to TrackRecord for more expressive checks
     private val lastCallbacks = HashMap<Network, INetworkMonitorCallbacks>()
+    private val moduleConnector = ConnectivityModuleConnector { _, action, _, _ ->
+        val intent = Intent(action)
+        val serviceName = TestNetworkStackService::class.qualifiedName
+                ?: fail("TestNetworkStackService name not found")
+        intent.component = ComponentName(context.packageName, serviceName)
+        return@ConnectivityModuleConnector intent
+    }.also { it.init(context) }
 
-    private class TestDependencies(private val context: Context) : Dependencies {
-        override fun addToServiceManager(service: IBinder) = Unit
-        override fun checkCallerUid() = Unit
-
-        override fun getConnectivityModuleConnector(): ConnectivityModuleConnector {
-            return ConnectivityModuleConnector { _, _, _, inSystemProcess ->
-                getNetworkStackIntent(inSystemProcess)
-            }.also { it.init(context) }
-        }
-
-        private fun getNetworkStackIntent(inSystemProcess: Boolean): Intent? {
-            // Simulate out-of-system-process config: in-process service not found (null intent)
-            if (inSystemProcess) return null
-            val intent = Intent(INetworkStackConnector::class.qualifiedName + TEST_ACTION_SUFFIX)
-            val serviceName = TestNetworkStackService::class.qualifiedName
-                    ?: fail("TestNetworkStackService name not found")
-            intent.component = ComponentName(context.packageName, serviceName)
-            return intent
+    fun start() {
+        moduleConnector.startModuleService(
+                INetworkStackConnector::class.qualifiedName + TEST_ACTION_SUFFIX,
+                NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK) { connector ->
+            onNetworkStackConnected(INetworkStackConnector.Stub.asInterface(connector))
         }
     }
 
diff --git a/tests/net/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt b/tests/net/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt
index db49e0b..14dddcb 100644
--- a/tests/net/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt
+++ b/tests/net/integration/src/com/android/server/net/integrationtests/ConnectivityServiceIntegrationTest.kt
@@ -157,7 +157,6 @@
         doReturn(IntArray(0)).`when`(systemConfigManager).getSystemPermissionUids(anyString())
 
         networkStackClient = TestNetworkStackClient(realContext)
-        networkStackClient.init()
         networkStackClient.start()
 
         service = TestConnectivityService(makeDependencies())
diff --git a/tests/net/java/com/android/server/ConnectivityServiceTest.java b/tests/net/java/com/android/server/ConnectivityServiceTest.java
index 0c2fb4e..db1334a 100644
--- a/tests/net/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/net/java/com/android/server/ConnectivityServiceTest.java
@@ -216,7 +216,6 @@
 import android.net.NetworkScore;
 import android.net.NetworkSpecifier;
 import android.net.NetworkStack;
-import android.net.NetworkStackClient;
 import android.net.NetworkStateSnapshot;
 import android.net.NetworkTestResultParcelable;
 import android.net.OemNetworkPreferences;
@@ -236,6 +235,7 @@
 import android.net.VpnManager;
 import android.net.VpnTransportInfo;
 import android.net.metrics.IpConnectivityLog;
+import android.net.networkstack.NetworkStackClientBase;
 import android.net.resolv.aidl.Nat64PrefixEventParcel;
 import android.net.resolv.aidl.PrivateDnsValidationEventParcel;
 import android.net.shared.NetworkMonitorUtils;
@@ -446,7 +446,7 @@
     @Mock NetworkStatsManager mStatsManager;
     @Mock IDnsResolver mMockDnsResolver;
     @Mock INetd mMockNetd;
-    @Mock NetworkStackClient mNetworkStack;
+    @Mock NetworkStackClientBase mNetworkStack;
     @Mock PackageManager mPackageManager;
     @Mock UserManager mUserManager;
     @Mock NotificationManager mNotificationManager;