diff --git a/core/api/src/main/java/org/onlab/onos/cluster/ControllerNodeToNodeId.java b/core/api/src/main/java/org/onlab/onos/cluster/ControllerNodeToNodeId.java
new file mode 100644
index 0000000..0891494
--- /dev/null
+++ b/core/api/src/main/java/org/onlab/onos/cluster/ControllerNodeToNodeId.java
@@ -0,0 +1,26 @@
+package org.onlab.onos.cluster;
+
+import com.google.common.base.Function;
+
+/**
+ * Function to convert ControllerNode to NodeId.
+ */
+public final class ControllerNodeToNodeId
+    implements Function<ControllerNode, NodeId> {
+
+    private static final ControllerNodeToNodeId INSTANCE = new ControllerNodeToNodeId();
+
+    @Override
+    public NodeId apply(ControllerNode input) {
+        return input.id();
+    }
+
+    /**
+     * Returns a Function to convert ControllerNode to NodeId.
+     *
+     * @return ControllerNodeToNodeId instance.
+     */
+    public static ControllerNodeToNodeId toNodeId() {
+        return INSTANCE;
+    }
+}