Preparing for change in ClusterService/Store implementation.
diff --git a/core/api/src/main/java/org/onlab/onos/cluster/ClusterAdminService.java b/core/api/src/main/java/org/onlab/onos/cluster/ClusterAdminService.java
index 4f98804..73137e1 100644
--- a/core/api/src/main/java/org/onlab/onos/cluster/ClusterAdminService.java
+++ b/core/api/src/main/java/org/onlab/onos/cluster/ClusterAdminService.java
@@ -1,11 +1,23 @@
 package org.onlab.onos.cluster;
 
+import org.onlab.packet.IpPrefix;
+
 /**
  * Service for administering the cluster node membership.
  */
 public interface ClusterAdminService {
 
     /**
+     * Adds a new controller node to the cluster.
+     *
+     * @param nodeId  controller node identifier
+     * @param ip      node IP listen address
+     * @param tcpPort tcp listen port
+     * @return newly added node
+     */
+    ControllerNode addNode(NodeId nodeId, IpPrefix ip, int tcpPort);
+
+    /**
      * Removes the specified node from the cluster node list.
      *
      * @param nodeId controller node identifier