+
+ /**
+ * Send Barrier message synchronously. The caller will be blocked until the
+ * solicitation response arrives.
+ *
+ * Solicit the network node to report whether all the requests sent so far
+ * are completed. When this call is done, caller knows that all past flow
+ * operations requested to the node in asynchronous fashion were satisfied
+ * by the network node and that in case of any failure, a message was sent
+ * to the controller.
+ *
+ * @param node
+ * The network node to solicit
+ * @return The status of this request containing the unique request id
+ */
+ Status syncSendBarrierMessage(Node node);
+
+ /**
+ * Send Barrier message asynchronously. The caller is not blocked.
+ *
+ * Solicit the network node to report whether all the requests sent so far
+ * are completed. When this call is done, caller knows that all past flow
+ * operations requested to the node in asynchronous fashion were satisfied
+ * by the network node and that in case of any failure, a message was sent
+ * to the controller.
+ *
+ * @param node
+ * The network node to solicit
+ * @return The status of this request containing the unique request id
+ */
+ Status asyncSendBarrierMessage(Node node);