diff --git a/core/java/android/net/MacAddress.aidl b/core/java/android/net/MacAddress.aidl
new file mode 100644
index 0000000..48a18a7
--- /dev/null
+++ b/core/java/android/net/MacAddress.aidl
@@ -0,0 +1,20 @@
+/**
+ *
+ * Copyright (C) 2019 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 MacAddress;
diff --git a/services/net/java/android/net/ip/IpClientCallbacks.java b/services/net/java/android/net/ip/IpClientCallbacks.java
index db01ae4..61cd88a 100644
--- a/services/net/java/android/net/ip/IpClientCallbacks.java
+++ b/services/net/java/android/net/ip/IpClientCallbacks.java
@@ -17,8 +17,11 @@
 package android.net.ip;
 
 import android.net.DhcpResults;
+import android.net.Layer2PacketParcelable;
 import android.net.LinkProperties;
 
+import java.util.List;
+
 /**
  * Callbacks for handling IpClient events.
  *
@@ -116,4 +119,9 @@
      * whenever 464xlat is being started or stopped.
      */
     public void setNeighborDiscoveryOffload(boolean enable) {}
+
+    /**
+     * Invoked on starting preconnection process.
+     */
+    public void onPreconnectionStart(List<Layer2PacketParcelable> packets) {}
 }
diff --git a/services/net/java/android/net/ip/IpClientManager.java b/services/net/java/android/net/ip/IpClientManager.java
index 1e653cd..4b7ed3c 100644
--- a/services/net/java/android/net/ip/IpClientManager.java
+++ b/services/net/java/android/net/ip/IpClientManager.java
@@ -234,7 +234,7 @@
                     slot, KeepalivePacketDataUtil.toStableParcelable(pkt));
             return true;
         } catch (RemoteException e) {
-            log("Error adding Keepalive Packet Filter ", e);
+            log("Error adding NAT-T Keepalive Packet Filter ", e);
             return false;
         } finally {
             Binder.restoreCallingIdentity(token);
@@ -272,4 +272,22 @@
             Binder.restoreCallingIdentity(token);
         }
     }
+
+    /**
+     * Notify IpClient that preconnection is complete and that the link is ready for use.
+     * The success parameter indicates whether the packets passed in by 'onPreconnectionStart'
+     * were successfully sent to the network or not.
+     */
+    public boolean notifyPreconnectionComplete(boolean success) {
+        final long token = Binder.clearCallingIdentity();
+        try {
+            mIpClient.notifyPreconnectionComplete(success);
+            return true;
+        } catch (RemoteException e) {
+            log("Error notifying IpClient Preconnection completed", e);
+            return false;
+        } finally {
+            Binder.restoreCallingIdentity(token);
+        }
+    }
 }
diff --git a/services/net/java/android/net/ip/IpClientUtil.java b/services/net/java/android/net/ip/IpClientUtil.java
index 714ade1..4d60e62 100644
--- a/services/net/java/android/net/ip/IpClientUtil.java
+++ b/services/net/java/android/net/ip/IpClientUtil.java
@@ -20,12 +20,14 @@
 
 import android.content.Context;
 import android.net.DhcpResultsParcelable;
+import android.net.Layer2PacketParcelable;
 import android.net.LinkProperties;
 import android.net.NetworkStackClient;
 import android.os.ConditionVariable;
 
 import java.io.FileDescriptor;
 import java.io.PrintWriter;
+import java.util.List;
 
 
 /**
@@ -176,6 +178,12 @@
             mCb.setNeighborDiscoveryOffload(enable);
         }
 
+        // Invoked on starting preconnection process.
+        @Override
+        public void onPreconnectionStart(List<Layer2PacketParcelable> packets) {
+            mCb.onPreconnectionStart(packets);
+        }
+
         @Override
         public int getInterfaceVersion() {
             return this.VERSION;