+/**
+ * When registering a listener at particular level of tree
+ * identified by instanceIdentifierPath.
+ * dataChangeListenerActorPath is path to actor that will
+ * receive the change event
+ * scope is the data change scope like BASE,ONE and SUBTREE
+ * defined in AsyncDataBroker.DataChangeScope
+ */
+
+message RegisterChangeListener{
+required InstanceIdentifier instanceIdentifierPath=1;
+required string dataChangeListenerActorPath=2;
+required int32 dataChangeScope=3;
+}
+/**
+* This is the reply for the RegisterChangeListener message
+* It contains the listenerRegistration actor path
+* that can be used to unregister the listener
+*/
+message RegisterChangeListenerReply{
+required string listenerRegistrationPath=1;
+
+}
+