diff --git a/framework/src/android/net/ConnectivityManager.java b/framework/src/android/net/ConnectivityManager.java
index 5d99b74..cfa517c 100644
--- a/framework/src/android/net/ConnectivityManager.java
+++ b/framework/src/android/net/ConnectivityManager.java
@@ -3952,7 +3952,8 @@
     @RequiresPermission(anyOf = {
             NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
             android.Manifest.permission.NETWORK_FACTORY})
-    public Network registerNetworkAgent(@NonNull INetworkAgent na, @NonNull NetworkInfo ni,
+    public NetworkAndAgentRegistryParcelable registerNetworkAgent(
+            @NonNull INetworkAgent na, @NonNull NetworkInfo ni,
             @NonNull LinkProperties lp, @NonNull NetworkCapabilities nc,
             @NonNull NetworkScore score, @NonNull NetworkAgentConfig config, int providerId) {
         return registerNetworkAgent(na, ni, lp, nc, null /* localNetworkConfig */, score, config,
@@ -3967,7 +3968,8 @@
     @RequiresPermission(anyOf = {
             NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK,
             android.Manifest.permission.NETWORK_FACTORY})
-    public Network registerNetworkAgent(@NonNull INetworkAgent na, @NonNull NetworkInfo ni,
+    public NetworkAndAgentRegistryParcelable registerNetworkAgent(
+            @NonNull INetworkAgent na, @NonNull NetworkInfo ni,
             @NonNull LinkProperties lp, @NonNull NetworkCapabilities nc,
             @Nullable LocalNetworkConfig localNetworkConfig, @NonNull NetworkScore score,
             @NonNull NetworkAgentConfig config, int providerId) {
diff --git a/framework/src/android/net/IConnectivityManager.aidl b/framework/src/android/net/IConnectivityManager.aidl
index 47b3316..a270684 100644
--- a/framework/src/android/net/IConnectivityManager.aidl
+++ b/framework/src/android/net/IConnectivityManager.aidl
@@ -30,6 +30,7 @@
 import android.net.LocalNetworkConfig;
 import android.net.Network;
 import android.net.NetworkAgentConfig;
+import android.net.NetworkAndAgentRegistryParcelable;
 import android.net.NetworkCapabilities;
 import android.net.NetworkInfo;
 import android.net.NetworkRequest;
@@ -146,7 +147,8 @@
 
     void declareNetworkRequestUnfulfillable(in NetworkRequest request);
 
-    Network registerNetworkAgent(in INetworkAgent na, in NetworkInfo ni, in LinkProperties lp,
+    NetworkAndAgentRegistryParcelable registerNetworkAgent(
+            in INetworkAgent na, in NetworkInfo ni, in LinkProperties lp,
             in NetworkCapabilities nc, in NetworkScore score,
             in LocalNetworkConfig localNetworkConfig, in NetworkAgentConfig config,
             in int factorySerialNumber);
diff --git a/framework/src/android/net/INetworkAgent.aidl b/framework/src/android/net/INetworkAgent.aidl
index fa5175c..c6beeca 100644
--- a/framework/src/android/net/INetworkAgent.aidl
+++ b/framework/src/android/net/INetworkAgent.aidl
@@ -26,7 +26,7 @@
  * @hide
  */
 oneway interface INetworkAgent {
-    void onRegistered(in INetworkAgentRegistry registry);
+    void onRegistered();
     void onDisconnected();
     void onBandwidthUpdateRequested();
     void onValidationStatusChanged(int validationStatus,
diff --git a/framework/src/android/net/INetworkAgentRegistry.aidl b/framework/src/android/net/INetworkAgentRegistry.aidl
index 61b27b5..afdd1ee 100644
--- a/framework/src/android/net/INetworkAgentRegistry.aidl
+++ b/framework/src/android/net/INetworkAgentRegistry.aidl
@@ -30,7 +30,7 @@
  * Interface for NetworkAgents to send network properties.
  * @hide
  */
-oneway interface INetworkAgentRegistry {
+interface INetworkAgentRegistry {
     void sendNetworkCapabilities(in NetworkCapabilities nc);
     void sendLinkProperties(in LinkProperties lp);
     // TODO: consider replacing this by "markConnected()" and removing
diff --git a/framework/src/android/net/NetworkAgent.java b/framework/src/android/net/NetworkAgent.java
index cefa1ea..08f5ecd 100644
--- a/framework/src/android/net/NetworkAgent.java
+++ b/framework/src/android/net/NetworkAgent.java
@@ -98,6 +98,7 @@
     @Nullable
     private volatile Network mNetwork;
 
+    // Null before the agent is registered
     @Nullable
     private volatile INetworkAgentRegistry mRegistry;
 
@@ -121,6 +122,8 @@
     private NetworkInfo mNetworkInfo;
     @NonNull
     private final Object mRegisterLock = new Object();
+    // TODO : move the preconnected queue to the system server and remove this
+    private boolean mConnected = false;
 
     /**
      * The ID of the {@link NetworkProvider} that created this object, or
@@ -606,16 +609,16 @@
         public void handleMessage(Message msg) {
             switch (msg.what) {
                 case EVENT_AGENT_CONNECTED: {
-                    if (mRegistry != null) {
-                        log("Received new connection while already connected!");
-                    } else {
-                        if (VDBG) log("NetworkAgent fully connected");
-                        synchronized (mPreConnectedQueue) {
-                            final INetworkAgentRegistry registry = (INetworkAgentRegistry) msg.obj;
-                            mRegistry = registry;
+                    // TODO : move the pre-connected queue to the system server, and remove
+                    // handling this EVENT_AGENT_CONNECTED message.
+                    synchronized (mPreConnectedQueue) {
+                        if (mConnected) {
+                            log("Received new connection while already connected!");
+                        } else {
+                            if (VDBG) log("NetworkAgent fully connected");
                             for (RegistryAction a : mPreConnectedQueue) {
                                 try {
-                                    a.execute(registry);
+                                    a.execute(mRegistry);
                                 } catch (RemoteException e) {
                                     Log.wtf(LOG_TAG, "Communication error with registry", e);
                                     // Fall through
@@ -623,6 +626,7 @@
                             }
                             mPreConnectedQueue.clear();
                         }
+                        mConnected = true;
                     }
                     break;
                 }
@@ -631,7 +635,7 @@
                     // let the client know CS is done with us.
                     onNetworkUnwanted();
                     synchronized (mPreConnectedQueue) {
-                        mRegistry = null;
+                        mConnected = false;
                     }
                     break;
                 }
@@ -758,20 +762,32 @@
             }
             final ConnectivityManager cm = (ConnectivityManager) mInitialConfiguration.context
                     .getSystemService(Context.CONNECTIVITY_SERVICE);
+            final NetworkAndAgentRegistryParcelable result;
             if (mInitialConfiguration.localNetworkConfig == null) {
                 // Call registerNetworkAgent without localNetworkConfig argument to pass
                 // android.net.cts.NetworkAgentTest#testAgentStartsInConnecting in old cts
-                mNetwork = cm.registerNetworkAgent(new NetworkAgentBinder(mHandler),
+                result = cm.registerNetworkAgent(new NetworkAgentBinder(mHandler),
                         new NetworkInfo(mInitialConfiguration.info),
                         mInitialConfiguration.properties, mInitialConfiguration.capabilities,
                         mInitialConfiguration.score, mInitialConfiguration.config, providerId);
             } else {
-                mNetwork = cm.registerNetworkAgent(new NetworkAgentBinder(mHandler),
+                result = cm.registerNetworkAgent(new NetworkAgentBinder(mHandler),
                         new NetworkInfo(mInitialConfiguration.info),
                         mInitialConfiguration.properties, mInitialConfiguration.capabilities,
                         mInitialConfiguration.localNetworkConfig, mInitialConfiguration.score,
                         mInitialConfiguration.config, providerId);
             }
+            if (null == result && Process.isApplicationUid(Process.myUid())) {
+                // Let it slide in tests to allow mocking, since NetworkAndAgentRegistryParcelable
+                // is not public and can't be instantiated by CTS. The danger here is that if
+                // this happens in production for some reason the code will crash later instead
+                // of here. If this is a system app, it will still crash as expected.
+                Log.e(LOG_TAG, "registerNetworkAgent returned null. This agent will not work. "
+                        + "Is ConnectivityManager a mock ?");
+            } else {
+                mNetwork = result.network;
+                mRegistry = result.registry;
+            }
             mInitialConfiguration = null; // All this memory can now be GC'd
         }
         return mNetwork;
@@ -787,8 +803,8 @@
         }
 
         @Override
-        public void onRegistered(@NonNull INetworkAgentRegistry registry) {
-            mHandler.sendMessage(mHandler.obtainMessage(EVENT_AGENT_CONNECTED, registry));
+        public void onRegistered() {
+            mHandler.sendMessage(mHandler.obtainMessage(EVENT_AGENT_CONNECTED));
         }
 
         @Override
@@ -913,11 +929,13 @@
      *
      * @hide
      */
-    public INetworkAgent registerForTest(final Network network) {
+    public INetworkAgent registerForTest(final Network network,
+            final INetworkAgentRegistry registry) {
         log("Registering NetworkAgent for test");
         synchronized (mRegisterLock) {
             mNetwork = network;
             mInitialConfiguration = null;
+            mRegistry = registry;
         }
         return new NetworkAgentBinder(mHandler);
     }
@@ -958,7 +976,7 @@
                         FrameworkConnectivityStatsLog.CORE_NETWORKING_TERRIBLE_ERROR_OCCURRED__ERROR_TYPE__TYPE_MESSAGE_QUEUED_BEFORE_CONNECT
                 );
             }
-            if (mRegistry != null) {
+            if (mConnected) {
                 try {
                     action.execute(mRegistry);
                 } catch (RemoteException e) {
diff --git a/framework/src/android/net/NetworkAndAgentRegistryParcelable.aidl b/framework/src/android/net/NetworkAndAgentRegistryParcelable.aidl
new file mode 100644
index 0000000..8c01bbc
--- /dev/null
+++ b/framework/src/android/net/NetworkAndAgentRegistryParcelable.aidl
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2025 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 android.net.INetworkAgentRegistry;
+import android.net.Network;
+
+/**
+ * A pair of Network and NetworkAgentRegistry.
+ *
+ * {@hide}
+ */
+@JavaDerive(toString=true)
+parcelable NetworkAndAgentRegistryParcelable {
+  Network network;
+  INetworkAgentRegistry registry;
+}
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index b2e49e7..6453d76 100644
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -228,6 +228,7 @@
 import android.net.Network;
 import android.net.NetworkAgent;
 import android.net.NetworkAgentConfig;
+import android.net.NetworkAndAgentRegistryParcelable;
 import android.net.NetworkCapabilities;
 import android.net.NetworkInfo;
 import android.net.NetworkInfo.DetailedState;
@@ -9316,7 +9317,7 @@
      * @param providerId the ID of the provider owning this NetworkAgent.
      * @return the network created for this agent.
      */
-    public Network registerNetworkAgent(INetworkAgent na,
+    public NetworkAndAgentRegistryParcelable registerNetworkAgent(INetworkAgent na,
             NetworkInfo networkInfo,
             LinkProperties linkProperties,
             NetworkCapabilities networkCapabilities,
@@ -9359,7 +9360,8 @@
         }
     }
 
-    private Network registerNetworkAgentInternal(INetworkAgent na, NetworkInfo networkInfo,
+    private NetworkAndAgentRegistryParcelable registerNetworkAgentInternal(
+            INetworkAgent na, NetworkInfo networkInfo,
             LinkProperties linkProperties, NetworkCapabilities networkCapabilities,
             NetworkScore currentScore, NetworkAgentConfig networkAgentConfig,
             @Nullable LocalNetworkConfig localNetworkConfig, int providerId,
@@ -9391,8 +9393,11 @@
         // NetworkAgentInfo registration will finish when the NetworkMonitor is created.
         // If the network disconnects or sends any other event before that, messages are deferred by
         // NetworkAgent until nai.connect(), which will be called when finalizing the
-        // registration.
-        return nai.network;
+        // registration. TODO : have NetworkAgentInfo defer them instead.
+        final NetworkAndAgentRegistryParcelable result = new NetworkAndAgentRegistryParcelable();
+        result.network = nai.network;
+        result.registry = nai.getRegistry();
+        return result;
     }
 
     private void handleRegisterNetworkAgent(NetworkAgentInfo nai, INetworkMonitor networkMonitor) {
diff --git a/service/src/com/android/server/connectivity/NetworkAgentInfo.java b/service/src/com/android/server/connectivity/NetworkAgentInfo.java
index e762a8e..d6bd659 100644
--- a/service/src/com/android/server/connectivity/NetworkAgentInfo.java
+++ b/service/src/com/android/server/connectivity/NetworkAgentInfo.java
@@ -639,6 +639,7 @@
     private final ConnectivityService.Dependencies mConnServiceDeps;
     private final Context mContext;
     private final Handler mHandler;
+    private final NetworkAgentMessageHandler mRegistry;
     private final QosCallbackTracker mQosCallbackTracker;
     private final INetd mNetd;
 
@@ -673,6 +674,7 @@
         mNetd = netd;
         mContext = context;
         mHandler = handler;
+        mRegistry = new NetworkAgentMessageHandler(mHandler);
         this.factorySerialNumber = factorySerialNumber;
         this.creatorUid = creatorUid;
         mLingerDurationMs = lingerDurationMs;
@@ -701,7 +703,7 @@
     public void notifyRegistered() {
         try {
             networkAgent.asBinder().linkToDeath(mDeathMonitor, 0);
-            networkAgent.onRegistered(new NetworkAgentMessageHandler(mHandler));
+            networkAgent.onRegistered();
         } catch (RemoteException e) {
             Log.e(TAG, "Error registering NetworkAgent", e);
             maybeUnlinkDeathMonitor();
@@ -1117,6 +1119,13 @@
         return mNetworkMonitor;
     }
 
+    /**
+     * Get the registry in this NetworkAgentInfo.
+     */
+    public INetworkAgentRegistry getRegistry() {
+        return mRegistry;
+    }
+
     // Functions for manipulating the requests satisfied by this network.
     //
     // These functions must only called on ConnectivityService's main thread.
diff --git a/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt b/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt
index 8fcc703..7031bfb 100644
--- a/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt
+++ b/tests/cts/net/src/android/net/cts/NetworkAgentTest.kt
@@ -154,10 +154,10 @@
 import java.security.MessageDigest
 import java.time.Duration
 import java.util.Arrays
-import java.util.Random
 import java.util.UUID
 import java.util.concurrent.Executors
 import kotlin.collections.ArrayList
+import kotlin.random.Random
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 import kotlin.test.assertFalse
@@ -266,7 +266,7 @@
     private class FakeConnectivityService {
         val mockRegistry = mock(INetworkAgentRegistry::class.java)
         private var agentField: INetworkAgent? = null
-        private val registry = object : INetworkAgentRegistry.Stub(),
+        val registry: INetworkAgentRegistry = object : INetworkAgentRegistry.Stub(),
                 INetworkAgentRegistry by mockRegistry {
             // asBinder has implementations in both INetworkAgentRegistry.Stub and mockRegistry, so
             // it needs to be disambiguated. Just fail the test as it should be unused here.
@@ -283,7 +283,7 @@
 
         fun connect(agent: INetworkAgent) {
             this.agentField = agent
-            agent.onRegistered(registry)
+            agent.onRegistered()
         }
 
         fun disconnect() = agent.onDisconnected()
@@ -412,7 +412,8 @@
     }
 
     private fun createNetworkAgentWithFakeCS() = createNetworkAgent().also {
-        mFakeConnectivityService.connect(it.registerForTest(Network(FAKE_NET_ID)))
+        val binder = it.registerForTest(Network(FAKE_NET_ID), mFakeConnectivityService.registry)
+        mFakeConnectivityService.connect(binder)
     }
 
     private fun TestableNetworkAgent.expectPostConnectionCallbacks(
@@ -1614,7 +1615,7 @@
         val s = Os.socket(AF_INET6, SOCK_DGRAM, 0)
         net.bindSocket(s)
         val content = ByteArray(16)
-        Random().nextBytes(content)
+        Random.nextBytes(content)
         Os.sendto(s, ByteBuffer.wrap(content), 0, REMOTE_ADDRESS, 7 /* port */)
         val match = reader.poll(DEFAULT_TIMEOUT_MS) {
             val udpStart = IPV6_HEADER_LEN + UDP_HEADER_LEN