diff --git a/src/main/java/net/onrc/onos/core/topology/ConfigState.java b/src/main/java/net/onrc/onos/core/topology/ConfigState.java
new file mode 100644
index 0000000..9d98f1a
--- /dev/null
+++ b/src/main/java/net/onrc/onos/core/topology/ConfigState.java
@@ -0,0 +1,15 @@
+package net.onrc.onos.core.topology;
+
+/**
+ * State to show configuration state of this element.
+ */
+public enum ConfigState {
+    /**
+     * Existence of the element was not configured, but discovered.
+     */
+    NOT_CONFIGURED,
+    /**
+     * Existence of the element was configured by operator.
+     */
+    CONFIGURED
+}