diff --git a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/PortImpl.java b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/PortImpl.java
index d0b605d..2e1086c 100644
--- a/src/main/java/net/onrc/onos/ofcontroller/networkgraph/PortImpl.java
+++ b/src/main/java/net/onrc/onos/ofcontroller/networkgraph/PortImpl.java
@@ -1,7 +1,13 @@
 package net.onrc.onos.ofcontroller.networkgraph;
 
+/**
+ * Port Object stored in In-memory Topology.
+ *
+ * TODO REMOVE following design memo: This object itself may hold the DBObject,
+ * but this Object itself will not issue any read/write to the DataStore.
+ */
 public class PortImpl extends NetworkGraphObject implements Port {
-	
+
 	//private long dpid;
 	private Switch sw;
 	private short number;
@@ -9,7 +15,7 @@
 	public PortImpl(NetworkGraph graph) {
 		super(graph);
 	}
-	
+
 	public void setPortNumber(short portNumber) {
 		number = portNumber;
 	}
@@ -18,12 +24,12 @@
 	public short getNumber() {
 		return number;
 	}
-	
+
 	/*
 	public void setDpid(long dpid) {
 		this.dpid = dpid;
 	}
-	
+
 	public long getDpid() {
 		return dpid;
 	}
@@ -40,12 +46,12 @@
 		// TODO Auto-generated method stub
 		return 0;
 	}
-	
+
 	@Override
 	public Switch getSwitch() {
 		return sw;
 	}
-	
+
 	public void setSwitch(Switch sw) {
 		this.sw = sw;
 	}