diff --git a/src/main/java/net/onrc/onos/ofcontroller/topology/Topology.java b/src/main/java/net/onrc/onos/ofcontroller/topology/Topology.java
index f356991..fc75591 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/topology/Topology.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/topology/Topology.java
@@ -265,9 +265,9 @@
 
 	    break;
 	}
-	default:
-		// unexpected case
-		break;
+	case ELEMENT_UNKNOWN:
+	    // TODO: Adding "assert(false);" here can be dangerous
+	    break;
 	}
 
 	return isModified;
@@ -318,9 +318,9 @@
 	    }
 	    break;
 	}
-	default:
-		// unexpected case
-		break;
+	case ELEMENT_UNKNOWN:
+	    // TODO: Adding "assert(false);" here can be dangerous
+	    break;
 	}
 
 	return isModified;