diff --git a/src/main/java/net/floodlightcontroller/devicemanager/IDeviceStorage.java b/src/main/java/net/floodlightcontroller/devicemanager/IDeviceStorage.java
index 582afe0..f41e32c 100644
--- a/src/main/java/net/floodlightcontroller/devicemanager/IDeviceStorage.java
+++ b/src/main/java/net/floodlightcontroller/devicemanager/IDeviceStorage.java
@@ -7,8 +7,9 @@
 	
 	public IDeviceObject addDevice(IDevice device);
 	public IDeviceObject updateDevice(IDevice device);
-	public IDeviceObject removeDevice(IDevice device);
+	public void removeDevice(IDevice device);
 	public IDeviceObject getDeviceByMac(String mac);
 	public IDeviceObject getDeviceByIP(String ip);
-	
+	public void changeDeviceAttachments(IDevice device);
+	public void changeDeviceIPv4Address(IDevice device);	
 }