diff --git a/core/java/android/provider/Settings.java b/core/java/android/provider/Settings.java
index 7f245394d2462..c75a02cc5a5de 100644
--- a/core/java/android/provider/Settings.java
+++ b/core/java/android/provider/Settings.java
@@ -5134,6 +5134,12 @@ public final class Settings {
          */
         public static final String SMS_SHORT_CODE_RULE = "sms_short_code_rule";
 
+       /**
+        * Used to select TCP's default initial receiver window size in segments - defaults to a build config value
+        * @hide
+        */
+       public static final String TCP_DEFAULT_INIT_RWND = "tcp_default_init_rwnd";
+
        /**
         * Used to disable Tethering on a device - defaults to true
         * @hide
diff --git a/services/java/com/android/server/ConnectivityService.java b/services/java/com/android/server/ConnectivityService.java
index 83a3bfd05fbb0..6a28fd67bb7e1 100644
--- a/services/java/com/android/server/ConnectivityService.java
+++ b/services/java/com/android/server/ConnectivityService.java
@@ -2757,6 +2757,15 @@ public class ConnectivityService extends IConnectivityManager.Stub {
             }
             setBufferSize(bufferSizes);
         }
+
+        final String defaultRwndKey = "net.tcp.default_init_rwnd";
+        int defaultRwndValue = SystemProperties.getInt(defaultRwndKey, 0);
+        Integer rwndValue = Settings.Global.getInt(mContext.getContentResolver(),
+            Settings.Global.TCP_DEFAULT_INIT_RWND, defaultRwndValue);
+        final String sysctlKey = "sys.sysctl.tcp_def_init_rwnd";
+        if (rwndValue != 0) {
+            SystemProperties.set(sysctlKey, rwndValue.toString());
+        }
     }
 
     /**