diff --git a/Tethering/common/TetheringLib/src/android/net/ITetheringEventCallback.aidl b/Tethering/common/TetheringLib/src/android/net/ITetheringEventCallback.aidl
index b4e3ba4..836761f 100644
--- a/Tethering/common/TetheringLib/src/android/net/ITetheringEventCallback.aidl
+++ b/Tethering/common/TetheringLib/src/android/net/ITetheringEventCallback.aidl
@@ -36,4 +36,5 @@
     void onTetherStatesChanged(in TetherStatesParcel states);
     void onTetherClientsChanged(in List<TetheredClient> clients);
     void onOffloadStatusChanged(int status);
+    void onSupportedTetheringTypes(long supportedBitmap);
 }
diff --git a/Tethering/common/TetheringLib/src/android/net/TetheringCallbackStartedParcel.aidl b/Tethering/common/TetheringLib/src/android/net/TetheringCallbackStartedParcel.aidl
index 253eacb..f33f846 100644
--- a/Tethering/common/TetheringLib/src/android/net/TetheringCallbackStartedParcel.aidl
+++ b/Tethering/common/TetheringLib/src/android/net/TetheringCallbackStartedParcel.aidl
@@ -26,7 +26,7 @@
  * @hide
  */
 parcelable TetheringCallbackStartedParcel {
-    boolean tetheringSupported;
+    long supportedTypes;
     Network upstreamNetwork;
     TetheringConfigurationParcel config;
     TetherStatesParcel states;
diff --git a/Tethering/common/TetheringLib/src/android/net/TetheringManager.java b/Tethering/common/TetheringLib/src/android/net/TetheringManager.java
index 6f9b33e..b3f0cf2 100644
--- a/Tethering/common/TetheringLib/src/android/net/TetheringManager.java
+++ b/Tethering/common/TetheringLib/src/android/net/TetheringManager.java
@@ -183,6 +183,12 @@
      */
     public static final int TETHERING_WIGIG = 6;
 
+    /**
+     * The int value of last tethering type.
+     * @hide
+     */
+    public static final int MAX_TETHERING_TYPE = TETHERING_WIGIG;
+
     /** @hide */
     @Retention(RetentionPolicy.SOURCE)
     @IntDef(value = {
@@ -520,6 +526,9 @@
         }
 
         @Override
+        public void onSupportedTetheringTypes(long supportedBitmap) { }
+
+        @Override
         public void onUpstreamChanged(Network network) { }
 
         @Override
@@ -1033,15 +1042,29 @@
         /**
          * Called when tethering supported status changed.
          *
+         * <p>This callback will be called immediately after the callback is
+         * registered, and never be called if there is changes afterward.
+         *
+         * <p>Tethering may be disabled via system properties, device configuration, or device
+         * policy restrictions.
+         *
+         * @param supported whether any tethering type is supported.
+         */
+        default void onTetheringSupported(boolean supported) {}
+
+        /**
+         * Called when tethering supported status changed.
+         *
          * <p>This will be called immediately after the callback is registered, and may be called
          * multiple times later upon changes.
          *
          * <p>Tethering may be disabled via system properties, device configuration, or device
          * policy restrictions.
          *
-         * @param supported The new supported status
+         * @param supportedTypes a set of @TetheringType which is supported.
+         * @hide
          */
-        default void onTetheringSupported(boolean supported) {}
+        default void onSupportedTetheringTypes(@NonNull Set<Integer> supportedTypes) {}
 
         /**
          * Called when tethering upstream changed.
@@ -1339,7 +1362,8 @@
                 @Override
                 public void onCallbackStarted(TetheringCallbackStartedParcel parcel) {
                     executor.execute(() -> {
-                        callback.onTetheringSupported(parcel.tetheringSupported);
+                        callback.onSupportedTetheringTypes(unpackBits(parcel.supportedTypes));
+                        callback.onTetheringSupported(parcel.supportedTypes != 0);
                         callback.onUpstreamChanged(parcel.upstreamNetwork);
                         sendErrorCallbacks(parcel.states);
                         sendRegexpsChanged(parcel.config);
@@ -1358,6 +1382,13 @@
                     });
                 }
 
+                @Override
+                public void onSupportedTetheringTypes(long supportedBitmap) {
+                    executor.execute(() -> {
+                        callback.onSupportedTetheringTypes(unpackBits(supportedBitmap));
+                    });
+                }
+
                 private void sendRegexpsChanged(TetheringConfigurationParcel parcel) {
                     callback.onTetherableInterfaceRegexpsChanged(new TetheringInterfaceRegexps(
                             parcel.tetherableBluetoothRegexs,
@@ -1396,6 +1427,23 @@
     }
 
     /**
+     * Unpack bitmap to a set of bit position intergers.
+     * @hide
+     */
+    public static ArraySet<Integer> unpackBits(long val) {
+        final ArraySet<Integer> result = new ArraySet<>(Long.bitCount(val));
+        int bitPos = 0;
+        while (val != 0) {
+            if ((val & 1) == 1) result.add(bitPos);
+
+            val = val >>> 1;
+            bitPos++;
+        }
+
+        return result;
+    }
+
+    /**
      * Remove tethering event callback previously registered with
      * {@link #registerTetheringEventCallback}.
      *
diff --git a/Tethering/proguard.flags b/Tethering/proguard.flags
index 7b5ae0d..2905e28 100644
--- a/Tethering/proguard.flags
+++ b/Tethering/proguard.flags
@@ -12,6 +12,11 @@
     native <methods>;
 }
 
+# Ensure runtime-visible field annotations are kept when using R8 full mode.
+-keepattributes RuntimeVisibleAnnotations,AnnotationDefault
+-keep interface com.android.networkstack.tethering.util.Struct$Field {
+    *;
+}
 -keepclassmembers public class * extends com.android.networkstack.tethering.util.Struct {
     *;
 }
diff --git a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
index bba0a40..ecb6478 100644
--- a/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
+++ b/Tethering/src/com/android/networkstack/tethering/BpfCoordinator.java
@@ -65,6 +65,7 @@
 import com.android.net.module.util.CollectionUtils;
 import com.android.net.module.util.InterfaceParams;
 import com.android.net.module.util.NetworkStackConstants;
+import com.android.net.module.util.Struct;
 import com.android.net.module.util.Struct.U32;
 import com.android.net.module.util.bpf.Tether4Key;
 import com.android.net.module.util.bpf.Tether4Value;
@@ -120,6 +121,8 @@
     private static final String TETHER_LIMIT_MAP_PATH = makeMapPath("limit");
     private static final String TETHER_ERROR_MAP_PATH = makeMapPath("error");
     private static final String TETHER_DEV_MAP_PATH = makeMapPath("dev");
+    private static final String DUMPSYS_RAWMAP_ARG_STATS = "--stats";
+    private static final String DUMPSYS_RAWMAP_ARG_UPSTREAM4 = "--upstream4";
 
     // Using "," as a separator is safe because base64 characters are [0-9a-zA-Z/=+].
     private static final String DUMP_BASE64_DELIMITER = ",";
@@ -1074,7 +1077,8 @@
         }
     }
 
-    private String ipv4RuleToBase64String(Tether4Key key, Tether4Value value) {
+    private <K extends Struct, V extends Struct> String bpfMapEntryToBase64String(
+            final K key, final V value) {
         final byte[] keyBytes = key.writeToBytes();
         final String keyBase64Str = Base64.encodeToString(keyBytes, Base64.DEFAULT)
                 .replace("\n", "");
@@ -1085,28 +1089,45 @@
         return keyBase64Str + DUMP_BASE64_DELIMITER + valueBase64Str;
     }
 
-    private void dumpRawIpv4ForwardingRuleMap(
-            BpfMap<Tether4Key, Tether4Value> map, IndentingPrintWriter pw) throws ErrnoException {
+    private <K extends Struct, V extends Struct> void dumpRawMap(BpfMap<K, V> map,
+            IndentingPrintWriter pw) throws ErrnoException {
         if (map == null) {
-            pw.println("No IPv4 support");
+            pw.println("No BPF support");
             return;
         }
         if (map.isEmpty()) {
-            pw.println("No rules");
+            pw.println("No entries");
             return;
         }
-        map.forEach((k, v) -> pw.println(ipv4RuleToBase64String(k, v)));
+        map.forEach((k, v) -> pw.println(bpfMapEntryToBase64String(k, v)));
     }
 
     /**
      * Dump raw BPF map in base64 encoded strings. For test only.
+     * Only allow to dump one map path once.
+     * Format:
+     * $ dumpsys tethering bpfRawMap --<map name>
      */
-    public void dumpRawMap(@NonNull IndentingPrintWriter pw) {
-        try (BpfMap<Tether4Key, Tether4Value> upstreamMap = mDeps.getBpfUpstream4Map()) {
-            // TODO: dump downstream map.
-            dumpRawIpv4ForwardingRuleMap(upstreamMap, pw);
-        } catch (ErrnoException e) {
-            pw.println("Error dumping IPv4 map: " + e);
+    public void dumpRawMap(@NonNull IndentingPrintWriter pw, @Nullable String[] args) {
+        // TODO: consider checking the arg order that <map name> is after "bpfRawMap". Probably
+        // it is okay for now because this is used by test only and test is supposed to use
+        // expected argument order.
+        // TODO: dump downstream4 map.
+        if (CollectionUtils.contains(args, DUMPSYS_RAWMAP_ARG_STATS)) {
+            try (BpfMap<TetherStatsKey, TetherStatsValue> statsMap = mDeps.getBpfStatsMap()) {
+                dumpRawMap(statsMap, pw);
+            } catch (ErrnoException e) {
+                pw.println("Error dumping stats map: " + e);
+            }
+            return;
+        }
+        if (CollectionUtils.contains(args, DUMPSYS_RAWMAP_ARG_UPSTREAM4)) {
+            try (BpfMap<Tether4Key, Tether4Value> upstreamMap = mDeps.getBpfUpstream4Map()) {
+                dumpRawMap(upstreamMap, pw);
+            } catch (ErrnoException e) {
+                pw.println("Error dumping IPv4 map: " + e);
+            }
+            return;
         }
     }
 
diff --git a/Tethering/src/com/android/networkstack/tethering/Tethering.java b/Tethering/src/com/android/networkstack/tethering/Tethering.java
index 0b607bd..4504829 100644
--- a/Tethering/src/com/android/networkstack/tethering/Tethering.java
+++ b/Tethering/src/com/android/networkstack/tethering/Tethering.java
@@ -135,6 +135,7 @@
 import com.android.internal.util.StateMachine;
 import com.android.modules.utils.build.SdkLevel;
 import com.android.net.module.util.BaseNetdUnsolicitedEventListener;
+import com.android.net.module.util.CollectionUtils;
 import com.android.networkstack.apishim.common.BluetoothPanShim;
 import com.android.networkstack.apishim.common.BluetoothPanShim.TetheredInterfaceCallbackShim;
 import com.android.networkstack.apishim.common.BluetoothPanShim.TetheredInterfaceRequestShim;
@@ -278,6 +279,11 @@
     private BluetoothPan mBluetoothPan;
     private PanServiceListener mBluetoothPanListener;
     private ArrayList<Pair<Boolean, IIntResultListener>> mPendingPanRequests;
+    // AIDL doesn't support Set<Integer>. Maintain a int bitmap here. When the bitmap is passed to
+    // TetheringManager, TetheringManager would convert it to a set of Integer types.
+    // mSupportedTypeBitmap should always be updated inside tethering internal thread but it may be
+    // read from binder thread which called TetheringService directly.
+    private volatile long mSupportedTypeBitmap;
 
     public Tethering(TetheringDependencies deps) {
         mLog.mark("Tethering.constructed");
@@ -494,6 +500,8 @@
         mUpstreamNetworkMonitor.setUpstreamConfig(mConfig.chooseUpstreamAutomatically,
                 mConfig.isDunRequired);
         reportConfigurationChanged(mConfig.toStableParcelable());
+
+        updateSupportedDownstreams(mConfig);
     }
 
     private void maybeDunSettingChanged() {
@@ -1513,26 +1521,6 @@
         return mConfig;
     }
 
-    boolean hasAnySupportedDownstream() {
-        if ((mConfig.tetherableUsbRegexs.length != 0)
-                || (mConfig.tetherableWifiRegexs.length != 0)
-                || (mConfig.tetherableBluetoothRegexs.length != 0)) {
-            return true;
-        }
-
-        // Before T, isTetheringSupported would return true if wifi, usb and bluetooth tethering are
-        // disabled (whole tethering settings would be hidden). This means tethering would also not
-        // support wifi p2p, ethernet tethering and mirrorlink. This is wrong but probably there are
-        // some devices in the field rely on this to disable tethering entirely.
-        if (!SdkLevel.isAtLeastT()) return false;
-
-        return (mConfig.tetherableWifiP2pRegexs.length != 0)
-                || (mConfig.tetherableNcmRegexs.length != 0)
-                || isEthernetSupported();
-    }
-
-    // TODO: using EtherentManager new API to check whether ethernet is supported when the API is
-    // ready to use.
     private boolean isEthernetSupported() {
         return mContext.getSystemService(Context.ETHERNET_SERVICE) != null;
     }
@@ -2322,7 +2310,7 @@
         mHandler.post(() -> {
             mTetheringEventCallbacks.register(callback, new CallbackCookie(hasListPermission));
             final TetheringCallbackStartedParcel parcel = new TetheringCallbackStartedParcel();
-            parcel.tetheringSupported = isTetheringSupported();
+            parcel.supportedTypes = mSupportedTypeBitmap;
             parcel.upstreamNetwork = mTetherUpstream;
             parcel.config = mConfig.toStableParcelable();
             parcel.states =
@@ -2361,6 +2349,22 @@
         });
     }
 
+    private void reportTetheringSupportedChange(final long supportedBitmap) {
+        final int length = mTetheringEventCallbacks.beginBroadcast();
+        try {
+            for (int i = 0; i < length; i++) {
+                try {
+                    mTetheringEventCallbacks.getBroadcastItem(i).onSupportedTetheringTypes(
+                            supportedBitmap);
+                } catch (RemoteException e) {
+                    // Not really very much to do here.
+                }
+            }
+        } finally {
+            mTetheringEventCallbacks.finishBroadcast();
+        }
+    }
+
     private void reportUpstreamChanged(UpstreamNetworkState ns) {
         final int length = mTetheringEventCallbacks.beginBroadcast();
         final Network network = (ns != null) ? ns.network : null;
@@ -2445,18 +2449,56 @@
         }
     }
 
+    private void updateSupportedDownstreams(final TetheringConfiguration config) {
+        final long preSupportedBitmap = mSupportedTypeBitmap;
+
+        if (!isTetheringAllowed() || mEntitlementMgr.isProvisioningNeededButUnavailable()) {
+            mSupportedTypeBitmap = 0;
+        } else {
+            mSupportedTypeBitmap = makeSupportedDownstreams(config);
+        }
+
+        if (preSupportedBitmap != mSupportedTypeBitmap) {
+            reportTetheringSupportedChange(mSupportedTypeBitmap);
+        }
+    }
+
+    private long makeSupportedDownstreams(final TetheringConfiguration config) {
+        long types = 0;
+        if (config.tetherableUsbRegexs.length != 0) types |= (1 << TETHERING_USB);
+
+        if (config.tetherableWifiRegexs.length != 0) types |= (1 << TETHERING_WIFI);
+
+        if (config.tetherableBluetoothRegexs.length != 0) types |= (1 << TETHERING_BLUETOOTH);
+
+        // Before T, isTetheringSupported would return true if wifi, usb and bluetooth tethering are
+        // disabled (whole tethering settings would be hidden). This means tethering would also not
+        // support wifi p2p, ethernet tethering and mirrorlink. This is wrong but probably there are
+        // some devices in the field rely on this to disable tethering entirely.
+        if (!SdkLevel.isAtLeastT() && types == 0) return types;
+
+        if (config.tetherableNcmRegexs.length != 0) types |= (1 << TETHERING_NCM);
+
+        if (config.tetherableWifiP2pRegexs.length != 0) types |= (1 << TETHERING_WIFI_P2P);
+
+        if (isEthernetSupported()) types |= (1 << TETHERING_ETHERNET);
+
+        return types;
+    }
+
     // if ro.tether.denied = true we default to no tethering
     // gservices could set the secure setting to 1 though to enable it on a build where it
     // had previously been turned off.
-    boolean isTetheringSupported() {
+    private boolean isTetheringAllowed() {
         final int defaultVal = mDeps.isTetheringDenied() ? 0 : 1;
         final boolean tetherSupported = Settings.Global.getInt(mContext.getContentResolver(),
                 Settings.Global.TETHER_SUPPORTED, defaultVal) != 0;
-        final boolean tetherEnabledInSettings = tetherSupported
+        return tetherSupported
                 && !mUserManager.hasUserRestriction(UserManager.DISALLOW_CONFIG_TETHERING);
+    }
 
-        return tetherEnabledInSettings && hasAnySupportedDownstream()
-                && !mEntitlementMgr.isProvisioningNeededButUnavailable();
+    boolean isTetheringSupported() {
+        return mSupportedTypeBitmap > 0;
     }
 
     private void dumpBpf(IndentingPrintWriter pw) {
@@ -2472,13 +2514,12 @@
                 writer, "  ");
 
         // Used for testing instead of human debug.
-        // TODO: add options to choose which map to dump.
-        if (argsContain(args, "bpfRawMap")) {
-            mBpfCoordinator.dumpRawMap(pw);
+        if (CollectionUtils.contains(args, "bpfRawMap")) {
+            mBpfCoordinator.dumpRawMap(pw, args);
             return;
         }
 
-        if (argsContain(args, "bpf")) {
+        if (CollectionUtils.contains(args, "bpf")) {
             dumpBpf(pw);
             return;
         }
@@ -2544,7 +2585,7 @@
 
         pw.println("Log:");
         pw.increaseIndent();
-        if (argsContain(args, "--short")) {
+        if (CollectionUtils.contains(args, "--short")) {
             pw.println("<log removed for brevity>");
         } else {
             mLog.dump(fd, pw, args);
@@ -2588,13 +2629,6 @@
         if (e != null) throw e;
     }
 
-    private static boolean argsContain(String[] args, String target) {
-        for (String arg : args) {
-            if (target.equals(arg)) return true;
-        }
-        return false;
-    }
-
     private void updateConnectedClients(final List<WifiClient> wifiClients) {
         if (mConnectedClientsTracker.updateConnectedClients(mTetherMainSM.getAllDownstreams(),
                 wifiClients)) {
diff --git a/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
index de81a38..e73b7d5 100644
--- a/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
+++ b/Tethering/tests/integration/src/android/net/EthernetTetheringTest.java
@@ -74,6 +74,8 @@
 import com.android.net.module.util.Struct;
 import com.android.net.module.util.bpf.Tether4Key;
 import com.android.net.module.util.bpf.Tether4Value;
+import com.android.net.module.util.bpf.TetherStatsKey;
+import com.android.net.module.util.bpf.TetherStatsValue;
 import com.android.net.module.util.structs.EthernetHeader;
 import com.android.net.module.util.structs.Icmpv6Header;
 import com.android.net.module.util.structs.Ipv4Header;
@@ -128,6 +130,13 @@
     // Kernel treats a confirmed UDP connection which active after two seconds as stream mode.
     // See upstream commit b7b1d02fc43925a4d569ec221715db2dfa1ce4f5.
     private static final int UDP_STREAM_TS_MS = 2000;
+    // Per RX UDP packet size: iphdr (20) + udphdr (8) + payload (2) = 30 bytes.
+    private static final int RX_UDP_PACKET_SIZE = 30;
+    private static final int RX_UDP_PACKET_COUNT = 456;
+    // Per TX UDP packet size: ethhdr (14) + iphdr (20) + udphdr (8) + payload (2) = 44 bytes.
+    private static final int TX_UDP_PACKET_SIZE = 44;
+    private static final int TX_UDP_PACKET_COUNT = 123;
+
     private static final LinkAddress TEST_IP4_ADDR = new LinkAddress("10.0.0.1/8");
     private static final LinkAddress TEST_IP6_ADDR = new LinkAddress("2001:db8:1::101/64");
     private static final InetAddress TEST_IP4_DNS = parseNumericAddress("8.8.8.8");
@@ -136,6 +145,8 @@
             ByteBuffer.wrap(new byte[] { (byte) 0x55, (byte) 0xaa });
 
     private static final String DUMPSYS_TETHERING_RAWMAP_ARG = "bpfRawMap";
+    private static final String DUMPSYS_RAWMAP_ARG_STATS = "--stats";
+    private static final String DUMPSYS_RAWMAP_ARG_UPSTREAM4 = "--upstream4";
     private static final String BASE64_DELIMITER = ",";
     private static final String LINE_DELIMITER = "\\n";
 
@@ -168,12 +179,13 @@
         mUiAutomation.adoptShellPermissionIdentity(
                 MANAGE_TEST_NETWORKS, NETWORK_SETTINGS, TETHER_PRIVILEGED, ACCESS_NETWORK_STATE,
                 CONNECTIVITY_USE_RESTRICTED_NETWORKS, DUMP);
-        mRunTests = mTm.isTetheringSupported() && mEm != null;
-        assumeTrue(mRunTests);
-
         mHandlerThread = new HandlerThread(getClass().getSimpleName());
         mHandlerThread.start();
         mHandler = new Handler(mHandlerThread.getLooper());
+
+        mRunTests = isEthernetTetheringSupported();
+        assumeTrue(mRunTests);
+
         mTetheredInterfaceRequester = new TetheredInterfaceRequester(mHandler, mEm);
     }
 
@@ -201,7 +213,6 @@
             mHandler.post(() -> reader.stop());
             mDownstreamReader = null;
         }
-        mHandlerThread.quitSafely();
         mTetheredInterfaceRequester.release();
         mEm.setIncludeTestInterfaces(false);
         maybeDeleteTestInterface();
@@ -212,6 +223,7 @@
         try {
             if (mRunTests) cleanUp();
         } finally {
+            mHandlerThread.quitSafely();
             mUiAutomation.dropShellPermissionIdentity();
         }
     }
@@ -400,6 +412,23 @@
         // client, which is not possible in this test.
     }
 
+    private boolean isEthernetTetheringSupported() throws Exception {
+        final CompletableFuture<Boolean> future = new CompletableFuture<>();
+        final TetheringEventCallback callback = new TetheringEventCallback() {
+            @Override
+            public void onSupportedTetheringTypes(Set<Integer> supportedTypes) {
+                future.complete(supportedTypes.contains(TETHERING_ETHERNET));
+            }
+        };
+
+        try {
+            mTm.registerTetheringEventCallback(mHandler::post, callback);
+            return future.get(TIMEOUT_MS, TimeUnit.MILLISECONDS);
+        } finally {
+            mTm.unregisterTetheringEventCallback(callback);
+        }
+    }
+
     private static final class MyTetheringEventCallback implements TetheringEventCallback {
         private final TetheringManager mTm;
         private final CountDownLatch mTetheringStartedLatch = new CountDownLatch(1);
@@ -938,27 +967,69 @@
                 return isExpectedUdpPacket(p, false /* hasEther */, PAYLOAD3);
             });
 
-            final HashMap<Tether4Key, Tether4Value> upstreamMap = pollIpv4UpstreamMapFromDump();
+            // [1] Verify IPv4 upstream rule map.
+            final HashMap<Tether4Key, Tether4Value> upstreamMap = pollRawMapFromDump(
+                    Tether4Key.class, Tether4Value.class, DUMPSYS_RAWMAP_ARG_UPSTREAM4);
             assertNotNull(upstreamMap);
             assertEquals(1, upstreamMap.size());
 
             final Map.Entry<Tether4Key, Tether4Value> rule =
                     upstreamMap.entrySet().iterator().next();
 
-            final Tether4Key key = rule.getKey();
-            assertEquals(IPPROTO_UDP, key.l4proto);
-            assertTrue(Arrays.equals(tethered.ipv4Addr.getAddress(), key.src4));
-            assertEquals(LOCAL_PORT, key.srcPort);
-            assertTrue(Arrays.equals(REMOTE_IP4_ADDR.getAddress(), key.dst4));
-            assertEquals(REMOTE_PORT, key.dstPort);
+            final Tether4Key upstream4Key = rule.getKey();
+            assertEquals(IPPROTO_UDP, upstream4Key.l4proto);
+            assertTrue(Arrays.equals(tethered.ipv4Addr.getAddress(), upstream4Key.src4));
+            assertEquals(LOCAL_PORT, upstream4Key.srcPort);
+            assertTrue(Arrays.equals(REMOTE_IP4_ADDR.getAddress(), upstream4Key.dst4));
+            assertEquals(REMOTE_PORT, upstream4Key.dstPort);
 
-            final Tether4Value value = rule.getValue();
+            final Tether4Value upstream4Value = rule.getValue();
             assertTrue(Arrays.equals(publicIp4Addr.getAddress(),
-                    InetAddress.getByAddress(value.src46).getAddress()));
-            assertEquals(LOCAL_PORT, value.srcPort);
+                    InetAddress.getByAddress(upstream4Value.src46).getAddress()));
+            assertEquals(LOCAL_PORT, upstream4Value.srcPort);
             assertTrue(Arrays.equals(REMOTE_IP4_ADDR.getAddress(),
-                    InetAddress.getByAddress(value.dst46).getAddress()));
-            assertEquals(REMOTE_PORT, value.dstPort);
+                    InetAddress.getByAddress(upstream4Value.dst46).getAddress()));
+            assertEquals(REMOTE_PORT, upstream4Value.dstPort);
+
+            // [2] Verify stats map.
+            // Transmit packets on both direction for verifying stats. Because we only care the
+            // packet count in stats test, we just reuse the existing packets to increaes
+            // the packet count on both direction.
+
+            // Send packets on original direction.
+            for (int i = 0; i < TX_UDP_PACKET_COUNT; i++) {
+                tester.verifyUpload(remote, originalPacket, p -> {
+                    Log.d(TAG, "Packet in upstream: " + dumpHexString(p));
+                    return isExpectedUdpPacket(p, false /* hasEther */, PAYLOAD);
+                });
+            }
+
+            // Send packets on reply direction.
+            for (int i = 0; i < RX_UDP_PACKET_COUNT; i++) {
+                remote.verifyDownload(tester, replyPacket, p -> {
+                    Log.d(TAG, "Packet in downstream: " + dumpHexString(p));
+                    return isExpectedUdpPacket(p, true/* hasEther */, PAYLOAD2);
+                });
+            }
+
+            // Dump stats map to verify.
+            final HashMap<TetherStatsKey, TetherStatsValue> statsMap = pollRawMapFromDump(
+                    TetherStatsKey.class, TetherStatsValue.class, DUMPSYS_RAWMAP_ARG_STATS);
+            assertNotNull(statsMap);
+            assertEquals(1, statsMap.size());
+
+            final Map.Entry<TetherStatsKey, TetherStatsValue> stats =
+                    statsMap.entrySet().iterator().next();
+
+            // TODO: verify the upstream index in TetherStatsKey.
+
+            final TetherStatsValue statsValue = stats.getValue();
+            assertEquals(RX_UDP_PACKET_COUNT, statsValue.rxPackets);
+            assertEquals(RX_UDP_PACKET_COUNT * RX_UDP_PACKET_SIZE, statsValue.rxBytes);
+            assertEquals(0, statsValue.rxErrors);
+            assertEquals(TX_UDP_PACKET_COUNT, statsValue.txPackets);
+            assertEquals(TX_UDP_PACKET_COUNT * TX_UDP_PACKET_SIZE, statsValue.txBytes);
+            assertEquals(0, statsValue.txErrors);
         }
     }
 
@@ -1003,7 +1074,8 @@
     }
 
     @Nullable
-    private Pair<Tether4Key, Tether4Value> parseTether4KeyValue(@NonNull String dumpStr) {
+    private <K extends Struct, V extends Struct> Pair<K, V> parseMapKeyValue(
+            Class<K> keyClass, Class<V> valueClass, @NonNull String dumpStr) {
         Log.w(TAG, "Parsing string: " + dumpStr);
 
         String[] keyValueStrs = dumpStr.split(BASE64_DELIMITER);
@@ -1016,36 +1088,38 @@
         Log.d(TAG, "keyBytes: " + dumpHexString(keyBytes));
         final ByteBuffer keyByteBuffer = ByteBuffer.wrap(keyBytes);
         keyByteBuffer.order(ByteOrder.nativeOrder());
-        final Tether4Key tether4Key = Struct.parse(Tether4Key.class, keyByteBuffer);
-        Log.w(TAG, "tether4Key: " + tether4Key);
+        final K k = Struct.parse(keyClass, keyByteBuffer);
 
         final byte[] valueBytes = Base64.decode(keyValueStrs[1], Base64.DEFAULT);
         Log.d(TAG, "valueBytes: " + dumpHexString(valueBytes));
         final ByteBuffer valueByteBuffer = ByteBuffer.wrap(valueBytes);
         valueByteBuffer.order(ByteOrder.nativeOrder());
-        final Tether4Value tether4Value = Struct.parse(Tether4Value.class, valueByteBuffer);
-        Log.w(TAG, "tether4Value: " + tether4Value);
+        final V v = Struct.parse(valueClass, valueByteBuffer);
 
-        return new Pair<>(tether4Key, tether4Value);
+        return new Pair<>(k, v);
     }
 
     @NonNull
-    private HashMap<Tether4Key, Tether4Value> dumpIpv4UpstreamMap() throws Exception {
-        final String rawMapStr = DumpTestUtils.dumpService(Context.TETHERING_SERVICE,
-                DUMPSYS_TETHERING_RAWMAP_ARG);
-        final HashMap<Tether4Key, Tether4Value> map = new HashMap<>();
+    private <K extends Struct, V extends Struct> HashMap<K, V> dumpAndParseRawMap(
+            Class<K> keyClass, Class<V> valueClass, @NonNull String mapArg)
+            throws Exception {
+        final String[] args = new String[] {DUMPSYS_TETHERING_RAWMAP_ARG, mapArg};
+        final String rawMapStr = DumpTestUtils.dumpService(Context.TETHERING_SERVICE, args);
+        final HashMap<K, V> map = new HashMap<>();
 
         for (final String line : rawMapStr.split(LINE_DELIMITER)) {
-            final Pair<Tether4Key, Tether4Value> rule = parseTether4KeyValue(line.trim());
+            final Pair<K, V> rule = parseMapKeyValue(keyClass, valueClass, line.trim());
             map.put(rule.first, rule.second);
         }
         return map;
     }
 
     @Nullable
-    private HashMap<Tether4Key, Tether4Value> pollIpv4UpstreamMapFromDump() throws Exception {
+    private <K extends Struct, V extends Struct> HashMap<K, V> pollRawMapFromDump(
+            Class<K> keyClass, Class<V> valueClass, @NonNull String mapArg)
+            throws Exception {
         for (int retryCount = 0; retryCount < DUMP_POLLING_MAX_RETRY; retryCount++) {
-            final HashMap<Tether4Key, Tether4Value> map = dumpIpv4UpstreamMap();
+            final HashMap<K, V> map = dumpAndParseRawMap(keyClass, valueClass, mapArg);
             if (!map.isEmpty()) return map;
 
             Thread.sleep(DUMP_POLLING_INTERVAL_MS);
diff --git a/Tethering/tests/unit/src/com/android/networkstack/tethering/TetheringTest.java b/Tethering/tests/unit/src/com/android/networkstack/tethering/TetheringTest.java
index 0388758..2fd7f48 100644
--- a/Tethering/tests/unit/src/com/android/networkstack/tethering/TetheringTest.java
+++ b/Tethering/tests/unit/src/com/android/networkstack/tethering/TetheringTest.java
@@ -142,6 +142,7 @@
 import android.net.TetheringCallbackStartedParcel;
 import android.net.TetheringConfigurationParcel;
 import android.net.TetheringInterface;
+import android.net.TetheringManager;
 import android.net.TetheringRequestParcel;
 import android.net.dhcp.DhcpLeaseParcelable;
 import android.net.dhcp.DhcpServerCallbacks;
@@ -175,6 +176,7 @@
 import android.telephony.PhoneStateListener;
 import android.telephony.TelephonyManager;
 import android.test.mock.MockContentResolver;
+import android.util.ArraySet;
 
 import androidx.annotation.NonNull;
 import androidx.test.filters.SmallTest;
@@ -211,6 +213,7 @@
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
+import java.util.Set;
 import java.util.Vector;
 
 @RunWith(AndroidJUnit4.class)
@@ -1696,6 +1699,7 @@
         private final ArrayList<TetherStatesParcel> mTetherStates = new ArrayList<>();
         private final ArrayList<Integer> mOffloadStatus = new ArrayList<>();
         private final ArrayList<List<TetheredClient>> mTetheredClients = new ArrayList<>();
+        private final ArrayList<Long> mSupportedBitmaps = new ArrayList<>();
 
         // This function will remove the recorded callbacks, so it must be called once for
         // each callback. If this is called after multiple callback, the order matters.
@@ -1748,6 +1752,10 @@
             assertTrue(leases.containsAll(result));
         }
 
+        public void expectSupportedTetheringTypes(Set<Integer> expectedTypes) {
+            assertEquals(expectedTypes, TetheringManager.unpackBits(mSupportedBitmaps.remove(0)));
+        }
+
         @Override
         public void onUpstreamChanged(Network network) {
             mActualUpstreams.add(network);
@@ -1780,11 +1788,17 @@
             mTetherStates.add(parcel.states);
             mOffloadStatus.add(parcel.offloadStatus);
             mTetheredClients.add(parcel.tetheredClients);
+            mSupportedBitmaps.add(parcel.supportedTypes);
         }
 
         @Override
         public void onCallbackStopped(int errorCode) { }
 
+        @Override
+        public void onSupportedTetheringTypes(long supportedBitmap) {
+            mSupportedBitmaps.add(supportedBitmap);
+        }
+
         public void assertNoUpstreamChangeCallback() {
             assertTrue(mActualUpstreams.isEmpty());
         }
@@ -2836,53 +2850,81 @@
         runStopUSBTethering();
     }
 
+    public static ArraySet<Integer> getAllSupportedTetheringTypes() {
+        return new ArraySet<>(new Integer[] { TETHERING_USB, TETHERING_NCM, TETHERING_WIFI,
+                TETHERING_WIFI_P2P, TETHERING_BLUETOOTH, TETHERING_ETHERNET });
+    }
+
     @Test
     public void testTetheringSupported() throws Exception {
+        final ArraySet<Integer> expectedTypes = getAllSupportedTetheringTypes();
+        // Check tethering is supported after initialization.
         setTetheringSupported(true /* supported */);
-        updateConfigAndVerifySupported(true /* supported */);
+        TestTetheringEventCallback callback = new TestTetheringEventCallback();
+        mTethering.registerTetheringEventCallback(callback);
+        mLooper.dispatchAll();
+        updateConfigAndVerifySupported(callback, expectedTypes);
 
         // Could disable tethering supported by settings.
         Settings.Global.putInt(mContentResolver, Settings.Global.TETHER_SUPPORTED, 0);
-        updateConfigAndVerifySupported(false /* supported */);
+        updateConfigAndVerifySupported(callback, new ArraySet<>());
 
         // Could disable tethering supported by user restriction.
         setTetheringSupported(true /* supported */);
+        updateConfigAndVerifySupported(callback, expectedTypes);
         when(mUserManager.hasUserRestriction(
                 UserManager.DISALLOW_CONFIG_TETHERING)).thenReturn(true);
-        updateConfigAndVerifySupported(false /* supported */);
+        updateConfigAndVerifySupported(callback, new ArraySet<>());
 
         // Tethering is supported if it has any supported downstream.
         setTetheringSupported(true /* supported */);
+        updateConfigAndVerifySupported(callback, expectedTypes);
+        // Usb tethering is not supported:
+        expectedTypes.remove(TETHERING_USB);
         when(mResources.getStringArray(R.array.config_tether_usb_regexs))
                 .thenReturn(new String[0]);
-        updateConfigAndVerifySupported(true /* supported */);
+        updateConfigAndVerifySupported(callback, expectedTypes);
+        // Wifi tethering is not supported:
+        expectedTypes.remove(TETHERING_WIFI);
         when(mResources.getStringArray(R.array.config_tether_wifi_regexs))
                 .thenReturn(new String[0]);
-        updateConfigAndVerifySupported(true /* supported */);
-
+        updateConfigAndVerifySupported(callback, expectedTypes);
+        // Bluetooth tethering is not supported:
+        expectedTypes.remove(TETHERING_BLUETOOTH);
+        when(mResources.getStringArray(R.array.config_tether_bluetooth_regexs))
+                .thenReturn(new String[0]);
 
         if (isAtLeastT()) {
-            when(mResources.getStringArray(R.array.config_tether_bluetooth_regexs))
-                    .thenReturn(new String[0]);
-            updateConfigAndVerifySupported(true /* supported */);
+            updateConfigAndVerifySupported(callback, expectedTypes);
+
+            // P2p tethering is not supported:
+            expectedTypes.remove(TETHERING_WIFI_P2P);
             when(mResources.getStringArray(R.array.config_tether_wifi_p2p_regexs))
                     .thenReturn(new String[0]);
-            updateConfigAndVerifySupported(true /* supported */);
+            updateConfigAndVerifySupported(callback, expectedTypes);
+            // Ncm tethering is not supported:
+            expectedTypes.remove(TETHERING_NCM);
             when(mResources.getStringArray(R.array.config_tether_ncm_regexs))
                     .thenReturn(new String[0]);
-            updateConfigAndVerifySupported(true /* supported */);
+            updateConfigAndVerifySupported(callback, expectedTypes);
+            // Ethernet tethering (last supported type) is not supported:
+            expectedTypes.remove(TETHERING_ETHERNET);
             mForceEthernetServiceUnavailable = true;
-            updateConfigAndVerifySupported(false /* supported */);
+            updateConfigAndVerifySupported(callback, new ArraySet<>());
+
         } else {
-            when(mResources.getStringArray(R.array.config_tether_bluetooth_regexs))
-                    .thenReturn(new String[0]);
-            updateConfigAndVerifySupported(false /* supported */);
+            // If wifi, usb and bluetooth are all not supported, all the types are not supported.
+            expectedTypes.clear();
+            updateConfigAndVerifySupported(callback, expectedTypes);
         }
     }
 
-    private void updateConfigAndVerifySupported(boolean supported) {
+    private void updateConfigAndVerifySupported(final TestTetheringEventCallback callback,
+            final ArraySet<Integer> expectedTypes) {
         sendConfigurationChanged();
-        assertEquals(supported, mTethering.isTetheringSupported());
+
+        assertEquals(expectedTypes.size() > 0, mTethering.isTetheringSupported());
+        callback.expectSupportedTetheringTypes(expectedTypes);
     }
     // TODO: Test that a request for hotspot mode doesn't interfere with an
     // already operating tethering mode interface.
diff --git a/framework-t/src/android/net/NetworkIdentitySet.java b/framework-t/src/android/net/NetworkIdentitySet.java
index ad3a958..d88408e 100644
--- a/framework-t/src/android/net/NetworkIdentitySet.java
+++ b/framework-t/src/android/net/NetworkIdentitySet.java
@@ -206,6 +206,7 @@
     public static int compare(@NonNull NetworkIdentitySet left, @NonNull NetworkIdentitySet right) {
         Objects.requireNonNull(left);
         Objects.requireNonNull(right);
+        if (left.isEmpty() && right.isEmpty()) return 0;
         if (left.isEmpty()) return -1;
         if (right.isEmpty()) return 1;
 
diff --git a/framework-t/src/android/net/NetworkStatsCollection.java b/framework-t/src/android/net/NetworkStatsCollection.java
index e385b33..b59a890 100644
--- a/framework-t/src/android/net/NetworkStatsCollection.java
+++ b/framework-t/src/android/net/NetworkStatsCollection.java
@@ -776,7 +776,7 @@
             if (!templateMatches(groupTemplate, key.ident)) continue;
             if (key.set >= NetworkStats.SET_DEBUG_START) continue;
 
-            final Key groupKey = new Key(null, key.uid, key.set, key.tag);
+            final Key groupKey = new Key(new NetworkIdentitySet(), key.uid, key.set, key.tag);
             NetworkStatsHistory groupHistory = grouped.get(groupKey);
             if (groupHistory == null) {
                 groupHistory = new NetworkStatsHistory(value.getBucketDuration());
diff --git a/service/src/com/android/server/ConnectivityService.java b/service/src/com/android/server/ConnectivityService.java
index a0e75ec..4835438 100644
--- a/service/src/com/android/server/ConnectivityService.java
+++ b/service/src/com/android/server/ConnectivityService.java
@@ -3266,11 +3266,12 @@
             return;
         }
 
-        pw.print("NetworkProviders for:");
+        pw.println("NetworkProviders for:");
+        pw.increaseIndent();
         for (NetworkProviderInfo npi : mNetworkProviderInfos.values()) {
-            pw.print(" " + npi.name);
+            pw.println(npi.providerId + ": " + npi.name);
         }
-        pw.println();
+        pw.decreaseIndent();
         pw.println();
 
         final NetworkAgentInfo defaultNai = getDefaultNetwork();
@@ -3319,6 +3320,14 @@
         pw.decreaseIndent();
         pw.println();
 
+        pw.println("Network Offers:");
+        pw.increaseIndent();
+        for (final NetworkOfferInfo offerInfo : mNetworkOffers) {
+            pw.println(offerInfo.offer);
+        }
+        pw.decreaseIndent();
+        pw.println();
+
         mLegacyTypeTracker.dump(pw);
 
         pw.println();
diff --git a/service/src/com/android/server/connectivity/NetworkOffer.java b/service/src/com/android/server/connectivity/NetworkOffer.java
index 1e975dd..eea382e 100644
--- a/service/src/com/android/server/connectivity/NetworkOffer.java
+++ b/service/src/com/android/server/connectivity/NetworkOffer.java
@@ -22,6 +22,7 @@
 import android.net.NetworkRequest;
 import android.os.RemoteException;
 
+import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.Objects;
 import java.util.Set;
@@ -143,6 +144,11 @@
 
     @Override
     public String toString() {
-        return "NetworkOffer [ Score " + score + " Caps " + caps + "]";
+        final ArrayList<Integer> neededRequestIds = new ArrayList<>();
+        for (final NetworkRequest request : mCurrentlyNeeded) {
+            neededRequestIds.add(request.requestId);
+        }
+        return "NetworkOffer [ Provider Id (" + providerId + ") " + score + " Caps "
+                + caps + " Needed by " + neededRequestIds + "]";
     }
 }
diff --git a/tests/cts/hostside/aidl/com/android/cts/net/hostside/IMyService.aidl b/tests/cts/hostside/aidl/com/android/cts/net/hostside/IMyService.aidl
index 28437c2..e7b2815 100644
--- a/tests/cts/hostside/aidl/com/android/cts/net/hostside/IMyService.aidl
+++ b/tests/cts/hostside/aidl/com/android/cts/net/hostside/IMyService.aidl
@@ -28,5 +28,5 @@
     void sendNotification(int notificationId, String notificationType);
     void registerNetworkCallback(in NetworkRequest request, in INetworkCallback cb);
     void unregisterNetworkCallback();
-    void scheduleJob(in JobInfo jobInfo);
+    int scheduleJob(in JobInfo jobInfo);
 }
diff --git a/tests/cts/hostside/app/src/com/android/cts/net/hostside/AbstractRestrictBackgroundNetworkTestCase.java b/tests/cts/hostside/app/src/com/android/cts/net/hostside/AbstractRestrictBackgroundNetworkTestCase.java
index f460180..96ce65f 100644
--- a/tests/cts/hostside/app/src/com/android/cts/net/hostside/AbstractRestrictBackgroundNetworkTestCase.java
+++ b/tests/cts/hostside/app/src/com/android/cts/net/hostside/AbstractRestrictBackgroundNetworkTestCase.java
@@ -16,6 +16,7 @@
 
 package com.android.cts.net.hostside;
 
+import static android.app.job.JobScheduler.RESULT_SUCCESS;
 import static android.net.ConnectivityManager.ACTION_RESTRICT_BACKGROUND_CHANGED;
 import static android.os.BatteryManager.BATTERY_PLUGGED_AC;
 import static android.os.BatteryManager.BATTERY_PLUGGED_USB;
@@ -151,7 +152,7 @@
 
     protected static final long TEMP_POWERSAVE_WHITELIST_DURATION_MS = 20_000; // 20 sec
 
-    private static final long BROADCAST_TIMEOUT_MS = 15_000;
+    private static final long BROADCAST_TIMEOUT_MS = 5_000;
 
     protected Context mContext;
     protected Instrumentation mInstrumentation;
@@ -855,7 +856,8 @@
                     .setRequiredNetworkType(JobInfo.NETWORK_TYPE_ANY)
                     .setTransientExtras(extras)
                     .build();
-            mServiceClient.scheduleJob(jobInfo);
+            assertEquals("Error scheduling " + jobInfo,
+                    RESULT_SUCCESS, mServiceClient.scheduleJob(jobInfo));
             forceRunJob(TEST_APP2_PKG, TEST_JOB_ID);
             if (latch.await(JOB_NETWORK_STATE_TIMEOUT_MS, TimeUnit.MILLISECONDS)) {
                 final int resultCode = result.get(0).first;
diff --git a/tests/cts/hostside/app/src/com/android/cts/net/hostside/MyServiceClient.java b/tests/cts/hostside/app/src/com/android/cts/net/hostside/MyServiceClient.java
index 8b70f9b..0610774 100644
--- a/tests/cts/hostside/app/src/com/android/cts/net/hostside/MyServiceClient.java
+++ b/tests/cts/hostside/app/src/com/android/cts/net/hostside/MyServiceClient.java
@@ -107,7 +107,7 @@
         mService.unregisterNetworkCallback();
     }
 
-    public void scheduleJob(JobInfo jobInfo) throws RemoteException {
-        mService.scheduleJob(jobInfo);
+    public int scheduleJob(JobInfo jobInfo) throws RemoteException {
+        return mService.scheduleJob(jobInfo);
     }
 }
diff --git a/tests/cts/hostside/app2/src/com/android/cts/net/hostside/app2/MyService.java b/tests/cts/hostside/app2/src/com/android/cts/net/hostside/app2/MyService.java
index f2a7b3f..3ed5391 100644
--- a/tests/cts/hostside/app2/src/com/android/cts/net/hostside/app2/MyService.java
+++ b/tests/cts/hostside/app2/src/com/android/cts/net/hostside/app2/MyService.java
@@ -165,10 +165,10 @@
         }
 
         @Override
-        public void scheduleJob(JobInfo jobInfo) {
+        public int scheduleJob(JobInfo jobInfo) {
             final JobScheduler jobScheduler = getApplicationContext()
                     .getSystemService(JobScheduler.class);
-            jobScheduler.schedule(jobInfo);
+            return jobScheduler.schedule(jobInfo);
         }
       };
 
diff --git a/tests/native/connectivity_native_test.cpp b/tests/native/connectivity_native_test.cpp
index 8b089ab..3db5265 100644
--- a/tests/native/connectivity_native_test.cpp
+++ b/tests/native/connectivity_native_test.cpp
@@ -14,14 +14,15 @@
  * limitations under the License.
  */
 
+#include <aidl/android/net/connectivity/aidl/ConnectivityNative.h>
+#include <android/binder_manager.h>
+#include <android/binder_process.h>
 #include <android-modules-utils/sdk_level.h>
 #include <cutils/misc.h>  // FIRST_APPLICATION_UID
 #include <gtest/gtest.h>
 #include <netinet/in.h>
-#include <android/binder_manager.h>
-#include <android/binder_process.h>
 
-#include <aidl/android/net/connectivity/aidl/ConnectivityNative.h>
+#include "bpf/BpfUtils.h"
 
 using aidl::android::net::connectivity::aidl::IConnectivityNative;
 
@@ -40,6 +41,10 @@
         if (!android::modules::sdklevel::IsAtLeastT()) GTEST_SKIP() <<
                 "Should be at least T device.";
 
+        // Skip test case if not on 5.4 kernel which is required by bpf prog.
+        if (!android::bpf::isAtLeastKernelVersion(5, 4, 0)) GTEST_SKIP() <<
+                "Kernel should be at least 5.4.";
+
         ASSERT_NE(nullptr, mService.get());
 
         // If there are already ports being blocked on device unblockAllPortsForBind() store
diff --git a/tests/unit/Android.bp b/tests/unit/Android.bp
index 545f7b9..5b926de 100644
--- a/tests/unit/Android.bp
+++ b/tests/unit/Android.bp
@@ -63,6 +63,7 @@
         "java/android/net/IpSecManagerTest.java",
         "java/android/net/IpSecTransformTest.java",
         "java/android/net/KeepalivePacketDataUtilTest.java",
+        "java/android/net/NetworkIdentitySetTest.kt",
         "java/android/net/NetworkIdentityTest.kt",
         "java/android/net/NetworkStats*.java",
         "java/android/net/NetworkTemplateTest.kt",
diff --git a/tests/unit/java/android/net/NetworkIdentitySetTest.kt b/tests/unit/java/android/net/NetworkIdentitySetTest.kt
new file mode 100644
index 0000000..d61ebf9
--- /dev/null
+++ b/tests/unit/java/android/net/NetworkIdentitySetTest.kt
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2022 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.content.Context
+import android.net.ConnectivityManager.TYPE_MOBILE
+import android.os.Build
+import android.telephony.TelephonyManager
+import com.android.testutils.DevSdkIgnoreRule
+import com.android.testutils.DevSdkIgnoreRunner
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mockito.mock
+import kotlin.test.assertEquals
+
+private const val TEST_IMSI1 = "testimsi1"
+
+@DevSdkIgnoreRule.IgnoreUpTo(Build.VERSION_CODES.S_V2)
+@RunWith(DevSdkIgnoreRunner::class)
+class NetworkIdentitySetTest {
+    private val mockContext = mock(Context::class.java)
+
+    private fun buildMobileNetworkStateSnapshot(
+        caps: NetworkCapabilities,
+        subscriberId: String
+    ): NetworkStateSnapshot {
+        return NetworkStateSnapshot(mock(Network::class.java), caps,
+                LinkProperties(), subscriberId, TYPE_MOBILE)
+    }
+
+    @Test
+    fun testCompare() {
+        val ident1 = NetworkIdentity.buildNetworkIdentity(mockContext,
+            buildMobileNetworkStateSnapshot(NetworkCapabilities(), TEST_IMSI1),
+            false /* defaultNetwork */, TelephonyManager.NETWORK_TYPE_UMTS)
+        val ident2 = NetworkIdentity.buildNetworkIdentity(mockContext,
+            buildMobileNetworkStateSnapshot(NetworkCapabilities(), TEST_IMSI1),
+            true /* defaultNetwork */, TelephonyManager.NETWORK_TYPE_UMTS)
+
+        // Verify that the results of comparing two empty sets are equal
+        assertEquals(0, NetworkIdentitySet.compare(NetworkIdentitySet(), NetworkIdentitySet()))
+
+        val identSet1 = NetworkIdentitySet()
+        val identSet2 = NetworkIdentitySet()
+        identSet1.add(ident1)
+        identSet2.add(ident2)
+        assertEquals(-1, NetworkIdentitySet.compare(NetworkIdentitySet(), identSet1))
+        assertEquals(1, NetworkIdentitySet.compare(identSet1, NetworkIdentitySet()))
+        assertEquals(0, NetworkIdentitySet.compare(identSet1, identSet1))
+        assertEquals(-1, NetworkIdentitySet.compare(identSet1, identSet2))
+    }
+}