diff --git a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphDiscoveryInterface.java b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphDiscoveryInterface.java
index 87edb28..cabcd38 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphDiscoveryInterface.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphDiscoveryInterface.java
@@ -1,5 +1,7 @@
 package net.onrc.onos.ofcontroller.networkgraph;
 
+import java.util.Collection;
+
 /**
  * Interface used by the Topology Discovery module to write topology-related
  * events.
@@ -9,8 +11,10 @@
      * Switch discovered event.
      *
      * @param switchEvent the switch event.
+     * @param portEvents the corresponding port events for the switch.
      */
-    public void putSwitchDiscoveryEvent(SwitchEvent switchEvent);
+    public void putSwitchDiscoveryEvent(SwitchEvent switchEvent,
+					Collection<PortEvent> portEvents);
 
     /**
      * Switch removed event.