diff --git a/Tethering/common/TetheringLib/Android.bp b/Tethering/common/TetheringLib/Android.bp
index e47d802..4bc8f93 100644
--- a/Tethering/common/TetheringLib/Android.bp
+++ b/Tethering/common/TetheringLib/Android.bp
@@ -56,6 +56,8 @@
         "src/android/net/TetheringConfigurationParcel.aidl",
         "src/android/net/TetheringRequestParcel.aidl",
         "src/android/net/TetherStatesParcel.aidl",
+        "src/android/net/TetheringInterface.aidl",
+        "src/android/net/TetheringInterface.java",
     ],
     path: "src"
 }
diff --git a/Tethering/common/TetheringLib/api/module-lib-current.txt b/Tethering/common/TetheringLib/api/module-lib-current.txt
index 6ddb122..0566040 100644
--- a/Tethering/common/TetheringLib/api/module-lib-current.txt
+++ b/Tethering/common/TetheringLib/api/module-lib-current.txt
@@ -28,13 +28,13 @@
   }
 
   public static interface TetheringManager.TetheringEventCallback {
-    method public default void onTetherableInterfaceRegexpsChanged(@NonNull android.net.TetheringManager.TetheringInterfaceRegexps);
+    method @Deprecated public default void onTetherableInterfaceRegexpsChanged(@NonNull android.net.TetheringManager.TetheringInterfaceRegexps);
   }
 
-  public static class TetheringManager.TetheringInterfaceRegexps {
-    method @NonNull public java.util.List<java.lang.String> getTetherableBluetoothRegexs();
-    method @NonNull public java.util.List<java.lang.String> getTetherableUsbRegexs();
-    method @NonNull public java.util.List<java.lang.String> getTetherableWifiRegexs();
+  @Deprecated public static class TetheringManager.TetheringInterfaceRegexps {
+    method @Deprecated @NonNull public java.util.List<java.lang.String> getTetherableBluetoothRegexs();
+    method @Deprecated @NonNull public java.util.List<java.lang.String> getTetherableUsbRegexs();
+    method @Deprecated @NonNull public java.util.List<java.lang.String> getTetherableWifiRegexs();
   }
 
 }
diff --git a/Tethering/common/TetheringLib/api/system-current.txt b/Tethering/common/TetheringLib/api/system-current.txt
index 105bab1..844ff64 100644
--- a/Tethering/common/TetheringLib/api/system-current.txt
+++ b/Tethering/common/TetheringLib/api/system-current.txt
@@ -19,6 +19,15 @@
     field @NonNull public static final android.os.Parcelable.Creator<android.net.TetheredClient.AddressInfo> CREATOR;
   }
 
+  public final class TetheringInterface implements android.os.Parcelable {
+    ctor public TetheringInterface(int, @NonNull String);
+    method public int describeContents();
+    method @NonNull public String getInterface();
+    method public int getType();
+    method public void writeToParcel(@NonNull android.os.Parcel, int);
+    field @NonNull public static final android.os.Parcelable.Creator<android.net.TetheringInterface> CREATOR;
+  }
+
   public class TetheringManager {
     method @RequiresPermission(android.Manifest.permission.ACCESS_NETWORK_STATE) public void registerTetheringEventCallback(@NonNull java.util.concurrent.Executor, @NonNull android.net.TetheringManager.TetheringEventCallback);
     method @RequiresPermission(anyOf={android.Manifest.permission.TETHER_PRIVILEGED, android.Manifest.permission.WRITE_SETTINGS}) public void requestLatestTetheringEntitlementResult(int, boolean, @NonNull java.util.concurrent.Executor, @NonNull android.net.TetheringManager.OnTetheringEntitlementResultListener);
@@ -26,7 +35,7 @@
     method @RequiresPermission(anyOf={android.Manifest.permission.TETHER_PRIVILEGED, android.Manifest.permission.WRITE_SETTINGS}) public void stopAllTethering();
     method @RequiresPermission(anyOf={android.Manifest.permission.TETHER_PRIVILEGED, android.Manifest.permission.WRITE_SETTINGS}) public void stopTethering(int);
     method @RequiresPermission(anyOf={android.Manifest.permission.TETHER_PRIVILEGED, android.Manifest.permission.ACCESS_NETWORK_STATE}) public void unregisterTetheringEventCallback(@NonNull android.net.TetheringManager.TetheringEventCallback);
-    field public static final String ACTION_TETHER_STATE_CHANGED = "android.net.conn.TETHER_STATE_CHANGED";
+    field @Deprecated public static final String ACTION_TETHER_STATE_CHANGED = "android.net.conn.TETHER_STATE_CHANGED";
     field public static final int CONNECTIVITY_SCOPE_GLOBAL = 1; // 0x1
     field public static final int CONNECTIVITY_SCOPE_LOCAL = 2; // 0x2
     field public static final String EXTRA_ACTIVE_LOCAL_ONLY = "android.net.extra.ACTIVE_LOCAL_ONLY";
@@ -74,10 +83,14 @@
   public static interface TetheringManager.TetheringEventCallback {
     method public default void onClientsChanged(@NonNull java.util.Collection<android.net.TetheredClient>);
     method public default void onError(@NonNull String, int);
+    method public default void onError(@NonNull android.net.TetheringInterface, int);
     method public default void onLocalOnlyInterfacesChanged(@NonNull java.util.List<java.lang.String>);
+    method public default void onLocalOnlyInterfacesChanged(@NonNull java.util.Set<android.net.TetheringInterface>);
     method public default void onOffloadStatusChanged(int);
     method public default void onTetherableInterfacesChanged(@NonNull java.util.List<java.lang.String>);
+    method public default void onTetherableInterfacesChanged(@NonNull java.util.Set<android.net.TetheringInterface>);
     method public default void onTetheredInterfacesChanged(@NonNull java.util.List<java.lang.String>);
+    method public default void onTetheredInterfacesChanged(@NonNull java.util.Set<android.net.TetheringInterface>);
     method public default void onTetheringSupported(boolean);
     method public default void onUpstreamChanged(@Nullable android.net.Network);
   }
diff --git a/Tethering/common/TetheringLib/src/android/net/TetherStatesParcel.aidl b/Tethering/common/TetheringLib/src/android/net/TetherStatesParcel.aidl
index 3d842b3..43262fb 100644
--- a/Tethering/common/TetheringLib/src/android/net/TetherStatesParcel.aidl
+++ b/Tethering/common/TetheringLib/src/android/net/TetherStatesParcel.aidl
@@ -16,15 +16,17 @@
 
 package android.net;
 
+import android.net.TetheringInterface;
+
 /**
  * Status details for tethering downstream interfaces.
  * {@hide}
  */
 parcelable TetherStatesParcel {
-    String[] availableList;
-    String[] tetheredList;
-    String[] localOnlyList;
-    String[] erroredIfaceList;
+    TetheringInterface[] availableList;
+    TetheringInterface[] tetheredList;
+    TetheringInterface[] localOnlyList;
+    TetheringInterface[] erroredIfaceList;
     // List of Last error code corresponding to each errored iface in erroredIfaceList. */
     // TODO: Improve this as b/143122247.
     int[] lastErrorList;
diff --git a/Tethering/common/TetheringLib/src/android/net/TetheringInterface.aidl b/Tethering/common/TetheringLib/src/android/net/TetheringInterface.aidl
new file mode 100644
index 0000000..7151984
--- /dev/null
+++ b/Tethering/common/TetheringLib/src/android/net/TetheringInterface.aidl
@@ -0,0 +1,18 @@
+/*
+ * 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 android.net;
+
+@JavaOnlyStableParcelable parcelable TetheringInterface;
diff --git a/Tethering/common/TetheringLib/src/android/net/TetheringInterface.java b/Tethering/common/TetheringLib/src/android/net/TetheringInterface.java
new file mode 100644
index 0000000..84cdef1
--- /dev/null
+++ b/Tethering/common/TetheringLib/src/android/net/TetheringInterface.java
@@ -0,0 +1,102 @@
+/*
+ * 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 android.net;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.annotation.SystemApi;
+import android.net.TetheringManager.TetheringType;
+import android.os.Parcel;
+import android.os.Parcelable;
+
+import java.util.Objects;
+
+/**
+ * The mapping of tethering interface and type.
+ * @hide
+ */
+@SystemApi
+public final class TetheringInterface implements Parcelable {
+    private final int mType;
+    private final String mInterface;
+
+    public TetheringInterface(@TetheringType int type, @NonNull String iface) {
+        Objects.requireNonNull(iface);
+        mType = type;
+        mInterface = iface;
+    }
+
+    private TetheringInterface(@NonNull Parcel in) {
+        this(in.readInt(), in.readString());
+    }
+
+    /** Get tethering type. */
+    public int getType() {
+        return mType;
+    }
+
+    /** Get tethering interface. */
+    @NonNull
+    public String getInterface() {
+        return mInterface;
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        dest.writeInt(mType);
+        dest.writeString(mInterface);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(mType, mInterface);
+    }
+
+    @Override
+    public boolean equals(@Nullable Object obj) {
+        if (!(obj instanceof TetheringInterface)) return false;
+        final TetheringInterface other = (TetheringInterface) obj;
+        return mType == other.mType && mInterface.equals(other.mInterface);
+    }
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @NonNull
+    public static final Creator<TetheringInterface> CREATOR = new Creator<TetheringInterface>() {
+        @NonNull
+        @Override
+        public TetheringInterface createFromParcel(@NonNull Parcel in) {
+            return new TetheringInterface(in);
+        }
+
+        @NonNull
+        @Override
+        public TetheringInterface[] newArray(int size) {
+            return new TetheringInterface[size];
+        }
+    };
+
+    @NonNull
+    @Override
+    public String toString() {
+        return "TetheringInterface {mType=" + mType
+                + ", mInterface=" + mInterface + "}";
+    }
+}
diff --git a/Tethering/common/TetheringLib/src/android/net/TetheringManager.java b/Tethering/common/TetheringLib/src/android/net/TetheringManager.java
index c64da8a..73ab908 100644
--- a/Tethering/common/TetheringLib/src/android/net/TetheringManager.java
+++ b/Tethering/common/TetheringLib/src/android/net/TetheringManager.java
@@ -30,6 +30,7 @@
 import android.os.RemoteException;
 import android.os.ResultReceiver;
 import android.util.ArrayMap;
+import android.util.ArraySet;
 import android.util.Log;
 
 import com.android.internal.annotations.GuardedBy;
@@ -43,6 +44,7 @@
 import java.util.HashMap;
 import java.util.List;
 import java.util.Objects;
+import java.util.Set;
 import java.util.concurrent.Executor;
 import java.util.function.Supplier;
 
@@ -83,7 +85,10 @@
      * {@code TetheringManager.EXTRA_ERRORED_TETHER} to indicate
      * the current state of tethering.  Each include a list of
      * interface names in that state (may be empty).
+     *
+     * @deprecated New client should use TetheringEventCallback instead.
      */
+    @Deprecated
     public static final String ACTION_TETHER_STATE_CHANGED =
             "android.net.conn.TETHER_STATE_CHANGED";
 
@@ -531,7 +536,7 @@
     /**
      * Attempt to both alter the mode of USB and Tethering of USB.
      *
-     * @deprecated New client should not use this API anymore. All clients should use
+     * @deprecated New clients should not use this API anymore. All clients should use
      * #startTethering or #stopTethering which encapsulate proper entitlement logic. If the API is
      * used and an entitlement check is needed, downstream USB tethering will be enabled but will
      * not have any upstream.
@@ -978,8 +983,13 @@
          * multiple times later upon changes.
          * @param reg The new regular expressions.
          *
+         * @deprecated New clients should use the callbacks with {@link TetheringInterface} which
+         * has the mapping between tethering type and interface. InterfaceRegex is no longer needed
+         * to determine the mapping of tethering type and interface.
+         *
          * @hide
          */
+        @Deprecated
         @SystemApi(client = MODULE_LIBRARIES)
         default void onTetherableInterfaceRegexpsChanged(@NonNull TetheringInterfaceRegexps reg) {}
 
@@ -994,15 +1004,43 @@
         default void onTetherableInterfacesChanged(@NonNull List<String> interfaces) {}
 
         /**
+         * Called when there was a change in the list of tetherable interfaces. Tetherable
+         * interface means this interface is available and can be used for tethering.
+         *
+         * <p>This will be called immediately after the callback is registered, and may be called
+         * multiple times later upon changes.
+         * @param interfaces The set of TetheringInterface of currently tetherable interface.
+         */
+        default void onTetherableInterfacesChanged(@NonNull Set<TetheringInterface> interfaces) {
+            // By default, the new callback calls the old callback, so apps
+            // implementing the old callback just work.
+            onTetherableInterfacesChanged(toIfaces(interfaces));
+        }
+
+        /**
          * Called when there was a change in the list of tethered interfaces.
          *
          * <p>This will be called immediately after the callback is registered, and may be called
          * multiple times later upon changes.
-         * @param interfaces The list of 0 or more String of currently tethered interface names.
+         * @param interfaces The lit of 0 or more String of currently tethered interface names.
          */
         default void onTetheredInterfacesChanged(@NonNull List<String> interfaces) {}
 
         /**
+         * Called when there was a change in the list of tethered interfaces.
+         *
+         * <p>This will be called immediately after the callback is registered, and may be called
+         * multiple times later upon changes.
+         * @param interfaces The set of 0 or more TetheringInterface of currently tethered
+         * interface.
+         */
+        default void onTetheredInterfacesChanged(@NonNull Set<TetheringInterface> interfaces) {
+            // By default, the new callback calls the old callback, so apps
+            // implementing the old callback just work.
+            onTetheredInterfacesChanged(toIfaces(interfaces));
+        }
+
+        /**
          * Called when there was a change in the list of local-only interfaces.
          *
          * <p>This will be called immediately after the callback is registered, and may be called
@@ -1012,6 +1050,20 @@
         default void onLocalOnlyInterfacesChanged(@NonNull List<String> interfaces) {}
 
         /**
+         * Called when there was a change in the list of local-only interfaces.
+         *
+         * <p>This will be called immediately after the callback is registered, and may be called
+         * multiple times later upon changes.
+         * @param interfaces The set of 0 or more TetheringInterface of active local-only
+         * interface.
+         */
+        default void onLocalOnlyInterfacesChanged(@NonNull Set<TetheringInterface> interfaces) {
+            // By default, the new callback calls the old callback, so apps
+            // implementing the old callback just work.
+            onLocalOnlyInterfacesChanged(toIfaces(interfaces));
+        }
+
+        /**
          * Called when an error occurred configuring tethering.
          *
          * <p>This will be called immediately after the callback is registered if the latest status
@@ -1022,6 +1074,20 @@
         default void onError(@NonNull String ifName, @TetheringIfaceError int error) {}
 
         /**
+         * Called when an error occurred configuring tethering.
+         *
+         * <p>This will be called immediately after the callback is registered if the latest status
+         * on the interface is an error, and may be called multiple times later upon changes.
+         * @param iface The interface that experienced the error.
+         * @param error One of {@code TetheringManager#TETHER_ERROR_*}.
+         */
+        default void onError(@NonNull TetheringInterface iface, @TetheringIfaceError int error) {
+            // By default, the new callback calls the old callback, so apps
+            // implementing the old callback just work.
+            onError(iface.getInterface(), error);
+        }
+
+        /**
          * Called when the list of tethered clients changes.
          *
          * <p>This callback provides best-effort information on connected clients based on state
@@ -1044,9 +1110,37 @@
     }
 
     /**
-     * Regular expressions used to identify tethering interfaces.
+     * Covert DownStreamInterface collection to interface String array list. Internal use only.
+     *
      * @hide
      */
+    public static ArrayList<String> toIfaces(Collection<TetheringInterface> tetherIfaces) {
+        final ArrayList<String> ifaces = new ArrayList<>();
+        for (TetheringInterface tether : tetherIfaces) {
+            ifaces.add(tether.getInterface());
+        }
+
+        return ifaces;
+    }
+
+    private static String[] toIfaces(TetheringInterface[] tetherIfaces) {
+        final String[] ifaces = new String[tetherIfaces.length];
+        for (int i = 0; i < tetherIfaces.length; i++) {
+            ifaces[i] = tetherIfaces[i].getInterface();
+        }
+
+        return ifaces;
+    }
+
+
+    /**
+     * Regular expressions used to identify tethering interfaces.
+     *
+     * @deprecated Instead of using regex to determine tethering type. New client could use the
+     * callbacks with {@link TetheringInterface} which has the mapping of type and interface.
+     * @hide
+     */
+    @Deprecated
     @SystemApi(client = MODULE_LIBRARIES)
     public static class TetheringInterfaceRegexps {
         private final String[] mTetherableBluetoothRegexs;
@@ -1114,10 +1208,10 @@
             }
             final ITetheringEventCallback remoteCallback = new ITetheringEventCallback.Stub() {
                 // Only accessed with a lock on this object
-                private final HashMap<String, Integer> mErrorStates = new HashMap<>();
-                private String[] mLastTetherableInterfaces = null;
-                private String[] mLastTetheredInterfaces = null;
-                private String[] mLastLocalOnlyInterfaces = null;
+                private final HashMap<TetheringInterface, Integer> mErrorStates = new HashMap<>();
+                private TetheringInterface[] mLastTetherableInterfaces = null;
+                private TetheringInterface[] mLastTetheredInterfaces = null;
+                private TetheringInterface[] mLastLocalOnlyInterfaces = null;
 
                 @Override
                 public void onUpstreamChanged(Network network) throws RemoteException {
@@ -1128,14 +1222,14 @@
 
                 private synchronized void sendErrorCallbacks(final TetherStatesParcel newStates) {
                     for (int i = 0; i < newStates.erroredIfaceList.length; i++) {
-                        final String iface = newStates.erroredIfaceList[i];
-                        final Integer lastError = mErrorStates.get(iface);
+                        final TetheringInterface tetherIface = newStates.erroredIfaceList[i];
+                        final Integer lastError = mErrorStates.get(tetherIface);
                         final int newError = newStates.lastErrorList[i];
                         if (newError != TETHER_ERROR_NO_ERROR
                                 && !Objects.equals(lastError, newError)) {
-                            callback.onError(iface, newError);
+                            callback.onError(tetherIface, newError);
                         }
-                        mErrorStates.put(iface, newError);
+                        mErrorStates.put(tetherIface, newError);
                     }
                 }
 
@@ -1144,7 +1238,7 @@
                     if (Arrays.equals(mLastTetherableInterfaces, newStates.availableList)) return;
                     mLastTetherableInterfaces = newStates.availableList.clone();
                     callback.onTetherableInterfacesChanged(
-                            Collections.unmodifiableList(Arrays.asList(mLastTetherableInterfaces)));
+                            Collections.unmodifiableSet((new ArraySet(mLastTetherableInterfaces))));
                 }
 
                 private synchronized void maybeSendTetheredIfacesChangedCallback(
@@ -1152,7 +1246,7 @@
                     if (Arrays.equals(mLastTetheredInterfaces, newStates.tetheredList)) return;
                     mLastTetheredInterfaces = newStates.tetheredList.clone();
                     callback.onTetheredInterfacesChanged(
-                            Collections.unmodifiableList(Arrays.asList(mLastTetheredInterfaces)));
+                            Collections.unmodifiableSet((new ArraySet(mLastTetheredInterfaces))));
                 }
 
                 private synchronized void maybeSendLocalOnlyIfacesChangedCallback(
@@ -1160,7 +1254,7 @@
                     if (Arrays.equals(mLastLocalOnlyInterfaces, newStates.localOnlyList)) return;
                     mLastLocalOnlyInterfaces = newStates.localOnlyList.clone();
                     callback.onLocalOnlyInterfacesChanged(
-                            Collections.unmodifiableList(Arrays.asList(mLastLocalOnlyInterfaces)));
+                            Collections.unmodifiableSet((new ArraySet(mLastLocalOnlyInterfaces))));
                 }
 
                 // Called immediately after the callbacks are registered.
@@ -1262,8 +1356,8 @@
         if (mTetherStatesParcel == null) return TETHER_ERROR_NO_ERROR;
 
         int i = 0;
-        for (String errored : mTetherStatesParcel.erroredIfaceList) {
-            if (iface.equals(errored)) return mTetherStatesParcel.lastErrorList[i];
+        for (TetheringInterface errored : mTetherStatesParcel.erroredIfaceList) {
+            if (iface.equals(errored.getInterface())) return mTetherStatesParcel.lastErrorList[i];
 
             i++;
         }
@@ -1327,7 +1421,7 @@
         mCallback.waitForStarted();
         if (mTetherStatesParcel == null) return new String[0];
 
-        return mTetherStatesParcel.availableList;
+        return toIfaces(mTetherStatesParcel.availableList);
     }
 
     /**
@@ -1341,7 +1435,7 @@
         mCallback.waitForStarted();
         if (mTetherStatesParcel == null) return new String[0];
 
-        return mTetherStatesParcel.tetheredList;
+        return toIfaces(mTetherStatesParcel.tetheredList);
     }
 
     /**
@@ -1361,7 +1455,7 @@
         mCallback.waitForStarted();
         if (mTetherStatesParcel == null) return new String[0];
 
-        return mTetherStatesParcel.erroredIfaceList;
+        return toIfaces(mTetherStatesParcel.erroredIfaceList);
     }
 
     /**