diff --git a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphImpl.java b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphImpl.java
index 9186e43..f50273e 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphImpl.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphImpl.java
@@ -25,8 +25,8 @@
  * re-ordering. e.g.) Link Add came in, but Switch was not there.
  *
  */
-public class NetworkGraphImpl extends AbstractNetworkGraph
-								implements NetworkGraphDiscoveryInterface {
+public class NetworkGraphImpl extends AbstractNetworkGraph implements
+	NetworkGraphDiscoveryInterface, NetworkGraphReplicationInterface {
 
     private static final Logger log = LoggerFactory
 	    .getLogger(NetworkGraphImpl.class);
@@ -675,4 +675,54 @@
 		// TODO implement
 		return true;
 	}
+
+	@Override
+	public void putSwitchReplicationEvent(SwitchEvent switchEvent) {
+		if (checkAddSwitchInvariant(switchEvent)) {
+			putSwitch(switchEvent);
+		}
+		// TODO handle invariant violation
+	}
+
+	@Override
+	public void removeSwitchReplicationEvent(SwitchEvent switchEvent) {
+	    // TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void putPortReplicationEvent(PortEvent portEvent) {
+	    // TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void removePortReplicationEvent(PortEvent portEvent) {
+	    // TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void putLinkReplicationEvent(LinkEvent linkEvent) {
+	    // TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void removeLinkReplicationEvent(LinkEvent linkEvent) {
+	    // TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void putDeviceReplicationEvent(DeviceEvent deviceEvent) {
+	    // TODO Auto-generated method stub
+
+	}
+
+	@Override
+	public void removeDeviceReplicationEvent(DeviceEvent deviceEvent) {
+	    // TODO Auto-generated method stub
+
+	}
 }
diff --git a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphReplicationInterface.java b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphReplicationInterface.java
new file mode 100644
index 0000000..6b77ece
--- /dev/null
+++ b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/NetworkGraphReplicationInterface.java
@@ -0,0 +1,17 @@
+package net.onrc.onos.ofcontroller.networkgraph;
+
+/**
+ * Interface to use to update Network Graph triggered by notification.
+ *
+ * Requested change by these methods will not be propagated down to DataStore
+ */
+public interface NetworkGraphReplicationInterface {
+	public void putSwitchReplicationEvent(SwitchEvent switchEvent);
+	public void removeSwitchReplicationEvent(SwitchEvent switchEvent);
+	public void putPortReplicationEvent(PortEvent portEvent);
+	public void removePortReplicationEvent(PortEvent portEvent);
+	public void putLinkReplicationEvent(LinkEvent linkEvent);
+	public void removeLinkReplicationEvent(LinkEvent linkEvent);
+	public void putDeviceReplicationEvent(DeviceEvent deviceEvent);
+	public void removeDeviceReplicationEvent(DeviceEvent deviceEvent);
+}