diff --git a/core/java/android/net/ConnectivityManager.java b/core/java/android/net/ConnectivityManager.java
index 674c58d..e8740c8 100644
--- a/core/java/android/net/ConnectivityManager.java
+++ b/core/java/android/net/ConnectivityManager.java
@@ -3169,10 +3169,10 @@
     /**
      * @hide
      * Register a NetworkAgent with ConnectivityService.
-     * @return NetID corresponding to NetworkAgent.
+     * @return Network corresponding to NetworkAgent.
      */
     @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
-    public int registerNetworkAgent(Messenger messenger, NetworkInfo ni, LinkProperties lp,
+    public Network registerNetworkAgent(Messenger messenger, NetworkInfo ni, LinkProperties lp,
             NetworkCapabilities nc, int score, NetworkMisc misc) {
         return registerNetworkAgent(messenger, ni, lp, nc, score, misc, NetworkProvider.ID_NONE);
     }
@@ -3180,10 +3180,10 @@
     /**
      * @hide
      * Register a NetworkAgent with ConnectivityService.
-     * @return NetID corresponding to NetworkAgent.
+     * @return Network corresponding to NetworkAgent.
      */
     @RequiresPermission(android.Manifest.permission.NETWORK_FACTORY)
-    public int registerNetworkAgent(Messenger messenger, NetworkInfo ni, LinkProperties lp,
+    public Network registerNetworkAgent(Messenger messenger, NetworkInfo ni, LinkProperties lp,
             NetworkCapabilities nc, int score, NetworkMisc misc, int providerId) {
         try {
             return mService.registerNetworkAgent(messenger, ni, lp, nc, score, misc, providerId);
diff --git a/core/java/android/net/IConnectivityManager.aidl b/core/java/android/net/IConnectivityManager.aidl
index e6a0379..3aee4d5 100644
--- a/core/java/android/net/IConnectivityManager.aidl
+++ b/core/java/android/net/IConnectivityManager.aidl
@@ -152,7 +152,7 @@
 
     void declareNetworkRequestUnfulfillable(in NetworkRequest request);
 
-    int registerNetworkAgent(in Messenger messenger, in NetworkInfo ni, in LinkProperties lp,
+    Network registerNetworkAgent(in Messenger messenger, in NetworkInfo ni, in LinkProperties lp,
             in NetworkCapabilities nc, int score, in NetworkMisc misc, in int factorySerialNumber);
 
     NetworkRequest requestNetwork(in NetworkCapabilities networkCapabilities,
diff --git a/core/java/android/net/NetworkAgent.java b/core/java/android/net/NetworkAgent.java
index 5f6cc6e..a5f7d53 100644
--- a/core/java/android/net/NetworkAgent.java
+++ b/core/java/android/net/NetworkAgent.java
@@ -44,9 +44,7 @@
  * @hide
  */
 public abstract class NetworkAgent extends Handler {
-    // Guaranteed to be valid (not NETID_UNSET), otherwise registerNetworkAgent() would have thrown
-    // an exception.
-    public final int netId;
+    public final Network network;
 
     private volatile AsyncChannel mAsyncChannel;
     private final String LOG_TAG;
@@ -245,7 +243,7 @@
         if (VDBG) log("Registering NetworkAgent");
         ConnectivityManager cm = (ConnectivityManager)mContext.getSystemService(
                 Context.CONNECTIVITY_SERVICE);
-        netId = cm.registerNetworkAgent(new Messenger(this), new NetworkInfo(ni),
+        network = cm.registerNetworkAgent(new Messenger(this), new NetworkInfo(ni),
                 new LinkProperties(lp), new NetworkCapabilities(nc), score, misc, providerId);
     }
 
diff --git a/services/core/java/com/android/server/ConnectivityService.java b/services/core/java/com/android/server/ConnectivityService.java
index 378bfdb..29f9e58 100644
--- a/services/core/java/com/android/server/ConnectivityService.java
+++ b/services/core/java/com/android/server/ConnectivityService.java
@@ -5480,7 +5480,10 @@
     // changes that would conflict throughout the automerger graph. Having this method temporarily
     // helps with the process of going through with all these dependent changes across the entire
     // tree.
-    public int registerNetworkAgent(Messenger messenger, NetworkInfo networkInfo,
+    /**
+     * Register a new agent. {@see #registerNetworkAgent} below.
+     */
+    public Network registerNetworkAgent(Messenger messenger, NetworkInfo networkInfo,
             LinkProperties linkProperties, NetworkCapabilities networkCapabilities,
             int currentScore, NetworkMisc networkMisc) {
         return registerNetworkAgent(messenger, networkInfo, linkProperties, networkCapabilities,
@@ -5501,8 +5504,9 @@
      *         {@link NetworkAgentInfo#getCurrentScore}.
      * @param networkMisc metadata about the network. This is never updated.
      * @param providerId the ID of the provider owning this NetworkAgent.
+     * @return the network created for this agent.
      */
-    public int registerNetworkAgent(Messenger messenger, NetworkInfo networkInfo,
+    public Network registerNetworkAgent(Messenger messenger, NetworkInfo networkInfo,
             LinkProperties linkProperties, NetworkCapabilities networkCapabilities,
             int currentScore, NetworkMisc networkMisc, int providerId) {
         enforceNetworkFactoryPermission();
@@ -5535,7 +5539,7 @@
         // If the network disconnects or sends any other event before that, messages are deferred by
         // NetworkAgent until nai.asyncChannel.connect(), which will be called when finalizing the
         // registration.
-        return nai.network.netId;
+        return nai.network;
     }
 
     private void handleRegisterNetworkAgent(NetworkAgentInfo nai, INetworkMonitor networkMonitor) {
@@ -5787,6 +5791,19 @@
         return INetd.PERMISSION_NONE;
     }
 
+    private void updateNetworkPermissions(@NonNull final NetworkAgentInfo nai,
+            @NonNull final NetworkCapabilities newNc) {
+        final int oldPermission = getNetworkPermission(nai.networkCapabilities);
+        final int newPermission = getNetworkPermission(newNc);
+        if (oldPermission != newPermission && nai.created && !nai.isVPN()) {
+            try {
+                mNMS.setNetworkPermission(nai.network.netId, newPermission);
+            } catch (RemoteException e) {
+                loge("Exception in setNetworkPermission: " + e);
+            }
+        }
+    }
+
     /**
      * Augments the NetworkCapabilities passed in by a NetworkAgent with capabilities that are
      * maintained here that the NetworkAgent is not aware of (e.g., validated, captive portal,
@@ -5858,21 +5875,11 @@
      * @param nai the network having its capabilities updated.
      * @param nc the new network capabilities.
      */
-    private void updateCapabilities(int oldScore, NetworkAgentInfo nai, NetworkCapabilities nc) {
+    private void updateCapabilities(final int oldScore, @NonNull final NetworkAgentInfo nai,
+            @NonNull final NetworkCapabilities nc) {
         NetworkCapabilities newNc = mixInCapabilities(nai, nc);
-
         if (Objects.equals(nai.networkCapabilities, newNc)) return;
-
-        final int oldPermission = getNetworkPermission(nai.networkCapabilities);
-        final int newPermission = getNetworkPermission(newNc);
-        if (oldPermission != newPermission && nai.created && !nai.isVPN()) {
-            try {
-                mNMS.setNetworkPermission(nai.network.netId, newPermission);
-            } catch (RemoteException e) {
-                loge("Exception in setNetworkPermission: " + e);
-            }
-        }
-
+        updateNetworkPermissions(nai, newNc);
         final NetworkCapabilities prevNc = nai.getAndSetNetworkCapabilities(newNc);
 
         updateUids(nai, prevNc, newNc);
@@ -6237,6 +6244,30 @@
         }
     }
 
+    // An accumulator class to gather the list of changes that result from a rematch.
+    // TODO : enrich to represent an entire set of changes to apply.
+    private static class NetworkReassignment {
+        static class NetworkBgStatePair {
+            @NonNull final NetworkAgentInfo mNetwork;
+            final boolean mOldBackground;
+            NetworkBgStatePair(@NonNull final NetworkAgentInfo network,
+                    final boolean oldBackground) {
+                mNetwork = network;
+                mOldBackground = oldBackground;
+            }
+        }
+
+        @NonNull private final Set<NetworkBgStatePair> mRematchedNetworks = new ArraySet<>();
+
+        @NonNull Iterable<NetworkBgStatePair> getRematchedNetworks() {
+            return mRematchedNetworks;
+        }
+
+        void addRematchedNetwork(@NonNull final NetworkBgStatePair network) {
+            mRematchedNetworks.add(network);
+        }
+    }
+
     private ArrayMap<NetworkRequestInfo, NetworkAgentInfo> computeRequestReassignmentForNetwork(
             @NonNull final NetworkAgentInfo newNetwork) {
         final int score = newNetwork.getCurrentScore();
@@ -6282,8 +6313,8 @@
     //   needed. A network is needed if it is the best network for
     //   one or more NetworkRequests, or if it is a VPN.
     //
-    // - Tears down newNetwork if it just became validated
-    //   but turns out to be unneeded.
+    // - Writes into the passed reassignment object all changes that should be done for
+    //   rematching this network with all requests, to be applied later.
     //
     // NOTE: This function only adds NetworkRequests that "newNetwork" could satisfy,
     // it does not remove NetworkRequests that other Networks could better satisfy.
@@ -6291,15 +6322,22 @@
     // This function should be used when possible instead of {@code rematchAllNetworksAndRequests}
     // as it performs better by a factor of the number of Networks.
     //
+    // TODO : stop writing to the passed reassignment. This is temporarily more useful, but
+    // it's unidiomatic Java and it's hard to read.
+    //
+    // @param changes a currently-building list of changes to write to
     // @param newNetwork is the network to be matched against NetworkRequests.
     // @param now the time the rematch starts, as returned by SystemClock.elapsedRealtime();
-    private void rematchNetworkAndRequests(NetworkAgentInfo newNetwork, long now) {
+    private void rematchNetworkAndRequests(@NonNull final NetworkReassignment changes,
+            @NonNull final NetworkAgentInfo newNetwork, final long now) {
         ensureRunningOnConnectivityServiceThread();
         if (!newNetwork.everConnected) return;
         boolean isNewDefault = false;
         NetworkAgentInfo oldDefaultNetwork = null;
 
-        final boolean wasBackgroundNetwork = newNetwork.isBackgroundNetwork();
+        changes.addRematchedNetwork(new NetworkReassignment.NetworkBgStatePair(newNetwork,
+                newNetwork.isBackgroundNetwork()));
+
         final int score = newNetwork.getCurrentScore();
 
         if (VDBG || DDBG) log("rematching " + newNetwork.name());
@@ -6402,39 +6440,12 @@
         if (newNetwork.getCurrentScore() != score) {
             Slog.wtf(TAG, String.format(
                     "BUG: %s changed score during rematch: %d -> %d",
-                   newNetwork.name(), score, newNetwork.getCurrentScore()));
+                    newNetwork.name(), score, newNetwork.getCurrentScore()));
         }
 
         // Notify requested networks are available after the default net is switched, but
         // before LegacyTypeTracker sends legacy broadcasts
         for (NetworkRequestInfo nri : addedRequests) notifyNetworkAvailable(newNetwork, nri);
-
-        // Finally, process listen requests and update capabilities if the background state has
-        // changed for this network. For consistency with previous behavior, send onLost callbacks
-        // before onAvailable.
-        processNewlyLostListenRequests(newNetwork);
-
-        // Maybe the network changed background states. Update its capabilities.
-        final boolean backgroundChanged = wasBackgroundNetwork != newNetwork.isBackgroundNetwork();
-        if (backgroundChanged) {
-            final NetworkCapabilities newNc = mixInCapabilities(newNetwork,
-                    newNetwork.networkCapabilities);
-
-            final int oldPermission = getNetworkPermission(newNetwork.networkCapabilities);
-            final int newPermission = getNetworkPermission(newNc);
-            if (oldPermission != newPermission) {
-                try {
-                    mNMS.setNetworkPermission(newNetwork.network.netId, newPermission);
-                } catch (RemoteException e) {
-                    loge("Exception in setNetworkPermission: " + e);
-                }
-            }
-
-            newNetwork.getAndSetNetworkCapabilities(newNc);
-            notifyNetworkCallbacks(newNetwork, ConnectivityManager.CALLBACK_CAP_CHANGED);
-        }
-
-        processNewlySatisfiedListenRequests(newNetwork);
     }
 
     /**
@@ -6456,12 +6467,24 @@
         // scoring network and then a higher scoring network, which could produce multiple
         // callbacks.
         Arrays.sort(nais);
+        final NetworkReassignment changes = new NetworkReassignment();
         for (final NetworkAgentInfo nai : nais) {
-            rematchNetworkAndRequests(nai, now);
+            rematchNetworkAndRequests(changes, nai, now);
         }
 
         final NetworkAgentInfo newDefaultNetwork = getDefaultNetwork();
 
+        for (final NetworkReassignment.NetworkBgStatePair event : changes.getRematchedNetworks()) {
+            // Process listen requests and update capabilities if the background state has
+            // changed for this network. For consistency with previous behavior, send onLost
+            // callbacks before onAvailable.
+            processNewlyLostListenRequests(event.mNetwork);
+            if (event.mOldBackground != event.mNetwork.isBackgroundNetwork()) {
+                applyBackgroundChangeForRematch(event.mNetwork);
+            }
+            processNewlySatisfiedListenRequests(event.mNetwork);
+        }
+
         for (final NetworkAgentInfo nai : nais) {
             // Rematching may have altered the linger state of some networks, so update all linger
             // timers. updateLingerState reads the state from the network agent and does nothing
@@ -6493,6 +6516,24 @@
         }
     }
 
+    /**
+     * Apply a change in background state resulting from rematching networks with requests.
+     *
+     * During rematch, a network may change background states by starting to satisfy or stopping
+     * to satisfy a foreground request. Listens don't count for this. When a network changes
+     * background states, its capabilities need to be updated and callbacks fired for the
+     * capability change.
+     *
+     * @param nai The network that changed background states
+     */
+    private void applyBackgroundChangeForRematch(@NonNull final NetworkAgentInfo nai) {
+        final NetworkCapabilities newNc = mixInCapabilities(nai, nai.networkCapabilities);
+        if (Objects.equals(nai.networkCapabilities, newNc)) return;
+        updateNetworkPermissions(nai, newNc);
+        nai.getAndSetNetworkCapabilities(newNc);
+        notifyNetworkCallbacks(nai, ConnectivityManager.CALLBACK_CAP_CHANGED);
+    }
+
     private void updateLegacyTypeTrackerAndVpnLockdownForRematch(
             @Nullable final NetworkAgentInfo oldDefaultNetwork,
             @Nullable final NetworkAgentInfo newDefaultNetwork,
diff --git a/services/core/java/com/android/server/TestNetworkService.java b/services/core/java/com/android/server/TestNetworkService.java
index d19d2dd..a7e36b2 100644
--- a/services/core/java/com/android/server/TestNetworkService.java
+++ b/services/core/java/com/android/server/TestNetworkService.java
@@ -219,7 +219,7 @@
             // Has to be in TestNetworkAgent to ensure all teardown codepaths properly clean up
             // resources, even for binder death or unwanted calls.
             synchronized (mTestNetworkTracker) {
-                mTestNetworkTracker.remove(netId);
+                mTestNetworkTracker.remove(network.netId);
             }
         }
     }
@@ -338,7 +338,7 @@
                                             callingUid,
                                             binder);
 
-                            mTestNetworkTracker.put(agent.netId, agent);
+                            mTestNetworkTracker.put(agent.network.netId, agent);
                         }
                     } catch (SocketException e) {
                         throw new UncheckedIOException(e);
diff --git a/tests/net/integration/util/com/android/server/NetworkAgentWrapper.java b/tests/net/integration/util/com/android/server/NetworkAgentWrapper.java
index 18474a8..0bf64b9 100644
--- a/tests/net/integration/util/com/android/server/NetworkAgentWrapper.java
+++ b/tests/net/integration/util/com/android/server/NetworkAgentWrapper.java
@@ -222,7 +222,7 @@
 
     @Override
     public Network getNetwork() {
-        return new Network(mNetworkAgent.netId);
+        return mNetworkAgent.network;
     }
 
     public void expectPreventReconnectReceived(long timeoutMs) {
diff --git a/tests/net/java/com/android/server/ConnectivityServiceTest.java b/tests/net/java/com/android/server/ConnectivityServiceTest.java
index b2d363e..1901a1d 100644
--- a/tests/net/java/com/android/server/ConnectivityServiceTest.java
+++ b/tests/net/java/com/android/server/ConnectivityServiceTest.java
@@ -575,7 +575,7 @@
                 }
             };
 
-            assertEquals(na.netId, nmNetworkCaptor.getValue().netId);
+            assertEquals(na.network.netId, nmNetworkCaptor.getValue().netId);
             mNmCallbacks = nmCbCaptor.getValue();
 
             mNmCallbacks.onNetworkMonitorCreated(mNetworkMonitor);