diff --git a/framework-t/src/android/net/EthernetNetworkUpdateRequest.java b/framework-t/src/android/net/EthernetNetworkUpdateRequest.java
index a626971..43f4c40 100644
--- a/framework-t/src/android/net/EthernetNetworkUpdateRequest.java
+++ b/framework-t/src/android/net/EthernetNetworkUpdateRequest.java
@@ -24,36 +24,52 @@
 
 import java.util.Objects;
 
-/** @hide */
+/**
+ * Represents a request to update an existing Ethernet interface.
+ *
+ * @see EthernetManager#updateConfiguration
+ *
+ * @hide
+ */
 @SystemApi
 public final class EthernetNetworkUpdateRequest implements Parcelable {
     @NonNull
     private final IpConfiguration mIpConfig;
-    @NonNull
+    @Nullable
     private final NetworkCapabilities mNetworkCapabilities;
 
+    /**
+     * @return the new {@link IpConfiguration}.
+     */
     @NonNull
     public IpConfiguration getIpConfiguration() {
         return new IpConfiguration(mIpConfig);
     }
 
-    @NonNull
+    /**
+     * Setting the {@link NetworkCapabilities} is optional in {@link EthernetNetworkUpdateRequest}.
+     * When set to null, the existing NetworkCapabilities are not updated.
+     *
+     * @return the new {@link NetworkCapabilities} or null.
+     */
+    @Nullable
     public NetworkCapabilities getNetworkCapabilities() {
-        return new NetworkCapabilities(mNetworkCapabilities);
+        return mNetworkCapabilities == null ? null : new NetworkCapabilities(mNetworkCapabilities);
     }
 
     private EthernetNetworkUpdateRequest(@NonNull final IpConfiguration ipConfig,
-            @NonNull final NetworkCapabilities networkCapabilities) {
+            @Nullable final NetworkCapabilities networkCapabilities) {
         Objects.requireNonNull(ipConfig);
-        Objects.requireNonNull(networkCapabilities);
-        mIpConfig = new IpConfiguration(ipConfig);
-        mNetworkCapabilities = new NetworkCapabilities(networkCapabilities);
+        mIpConfig = ipConfig;
+        mNetworkCapabilities = networkCapabilities;
     }
 
     private EthernetNetworkUpdateRequest(@NonNull final Parcel source) {
         Objects.requireNonNull(source);
-        mIpConfig = IpConfiguration.CREATOR.createFromParcel(source);
-        mNetworkCapabilities = NetworkCapabilities.CREATOR.createFromParcel(source);
+        mIpConfig = source.readParcelable(IpConfiguration.class.getClassLoader(),
+                IpConfiguration.class);
+        mNetworkCapabilities = source.readParcelable(NetworkCapabilities.class.getClassLoader(),
+                NetworkCapabilities.class);
     }
 
     /**
@@ -75,7 +91,8 @@
         public Builder(@NonNull final EthernetNetworkUpdateRequest request) {
             Objects.requireNonNull(request);
             mBuilderIpConfig = new IpConfiguration(request.mIpConfig);
-            mBuilderNetworkCapabilities = new NetworkCapabilities(request.mNetworkCapabilities);
+            mBuilderNetworkCapabilities = null == request.mNetworkCapabilities
+                    ? null : new NetworkCapabilities(request.mNetworkCapabilities);
         }
 
         /**
@@ -85,7 +102,6 @@
          */
         @NonNull
         public Builder setIpConfiguration(@NonNull final IpConfiguration ipConfig) {
-            Objects.requireNonNull(ipConfig);
             mBuilderIpConfig = new IpConfiguration(ipConfig);
             return this;
         }
@@ -96,9 +112,8 @@
          * @return The builder to facilitate chaining.
          */
         @NonNull
-        public Builder setNetworkCapabilities(@NonNull final NetworkCapabilities nc) {
-            Objects.requireNonNull(nc);
-            mBuilderNetworkCapabilities = new NetworkCapabilities(nc);
+        public Builder setNetworkCapabilities(@Nullable final NetworkCapabilities nc) {
+            mBuilderNetworkCapabilities = nc == null ? null : new NetworkCapabilities(nc);
             return this;
         }
 
@@ -135,8 +150,8 @@
 
     @Override
     public void writeToParcel(@NonNull Parcel dest, int flags) {
-        mIpConfig.writeToParcel(dest, flags);
-        mNetworkCapabilities.writeToParcel(dest, flags);
+        dest.writeParcelable(mIpConfig, flags);
+        dest.writeParcelable(mNetworkCapabilities, flags);
     }
 
     @Override