InterestPacket, ContentPacket, Face classes added

diff --git a/model/ndn_interestpacket.h b/model/ndn_interestpacket.h
new file mode 100644
index 0000000..fddc136
--- /dev/null
+++ b/model/ndn_interestpacket.h
@@ -0,0 +1,25 @@
+//
+//  ndn_interestpacket.h
+//  Abstraction
+//
+//  Copyright 2011 UCLA. All rights reserved.
+//
+
+#ifndef ndn_interestpacket_h
+#define ndn_interestpacket_h
+
+//#define CCN_INTEREST_LIFETIME_SEC 4
+//#define CCN_INTEREST_LIFETIME_MICROSEC (CCN_INTEREST_LIFETIME_SEC * 1000000)
+
+#include "ns3/header.h"
+#include <ns3/packet.h>
+
+namespace ns3
+{
+    class InterestPacket : public Packet 
+    {
+        
+    };
+}
+
+#endif 
\ No newline at end of file