Initial implementation for DistributedFlowRuleStore utilizing master/backup replication
diff --git a/core/store/dist/src/main/java/org/onlab/onos/store/flow/impl/FlowStoreMessageSubjects.java b/core/store/dist/src/main/java/org/onlab/onos/store/flow/impl/FlowStoreMessageSubjects.java
new file mode 100644
index 0000000..a43dad6
--- /dev/null
+++ b/core/store/dist/src/main/java/org/onlab/onos/store/flow/impl/FlowStoreMessageSubjects.java
@@ -0,0 +1,15 @@
+package org.onlab.onos.store.flow.impl;
+
+import org.onlab.onos.store.cluster.messaging.MessageSubject;
+
+/**
+ * MessageSubjects used by DistributedFlowRuleStore peer-peer communication.
+ */
+public final class FlowStoreMessageSubjects {
+    private FlowStoreMessageSubjects() {}
+    public static final  MessageSubject STORE_FLOW_RULE = new MessageSubject("peer-forward-store-flow-rule");
+    public static final MessageSubject DELETE_FLOW_RULE = new MessageSubject("peer-forward-delete-flow-rule");
+    public static final MessageSubject ADD_OR_UPDATE_FLOW_RULE =
+        new MessageSubject("peer-forward-add-or-update-flow-rule");
+    public static final MessageSubject REMOVE_FLOW_RULE = new MessageSubject("peer-forward-remove-flow-rule");
+}