diff --git a/nsync/src/sync-full-state.cc b/nsync/src/sync-full-state.cc
new file mode 100644
index 0000000..eb9ca4c
--- /dev/null
+++ b/nsync/src/sync-full-state.cc
@@ -0,0 +1,126 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
+/*
+ * Copyright (c) 2012 University of California, Los Angeles
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation;
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Author: Zhenkai Zhu <zhenkai@cs.ucla.edu>
+ *         Chaoyi Bian <bcy@pku.edu.cn>
+ *	   Alexander Afanasyev <alexander.afanasyev@ucla.edu>
+ */
+
+#include "sync-full-state.h"
+
+#include <boost/make_shared.hpp>
+#include <boost/lambda/lambda.hpp>
+#include <boost/lambda/bind.hpp>
+#include <boost/foreach.hpp>
+#include <boost/assert.hpp>
+
+#include "sync-full-leaf.h"
+
+using namespace boost;
+namespace ll = boost::lambda;
+
+namespace Sync {
+
+
+FullState::FullState ()
+// m_lastUpdated is initialized to "not_a_date_time" in normal lib mode and to "0" time in NS-3 mode
+{
+}
+
+FullState::~FullState ()
+{
+}
+
+ndn::time::Duration
+FullState::getTimeFromLastUpdate () const
+{
+  return ndn::time::now() - m_lastUpdated;
+}
+
+DigestConstPtr
+FullState::getDigest ()
+{
+  if (!m_digest)
+    {
+      m_digest = make_shared<Digest> ();
+      if (m_leaves.get<ordered> ().size () > 0)
+        {
+          BOOST_FOREACH (LeafConstPtr leaf, m_leaves.get<ordered> ())
+            {
+              FullLeafConstPtr fullLeaf = dynamic_pointer_cast<const FullLeaf> (leaf);
+              BOOST_ASSERT (fullLeaf != 0);
+              *m_digest << fullLeaf->getDigest ();
+            }
+          m_digest->finalize ();
+        }
+      else
+        {
+          std::istringstream is ("00"); //zero state
+          is >> *m_digest;
+        }
+    }
+
+  return m_digest;
+}
+
+// from State
+boost::tuple<bool/*inserted*/, bool/*updated*/, SeqNo/*oldSeqNo*/>
+FullState::update (NameInfoConstPtr info, const SeqNo &seq)
+{
+  m_lastUpdated = ndn::time::now();
+
+
+  m_digest.reset ();
+
+  LeafContainer::iterator item = m_leaves.find (info);
+  if (item == m_leaves.end ())
+    {
+      m_leaves.insert (make_shared<FullLeaf> (info, cref (seq)));
+      return make_tuple (true, false, SeqNo ());
+    }
+  else
+    {
+      if ((*item)->getSeq () == seq || seq < (*item)->getSeq ())
+        {
+          return make_tuple (false, false, SeqNo ());
+        }
+
+      SeqNo old = (*item)->getSeq ();
+      m_leaves.modify (item,
+                       ll::bind (&Leaf::setSeq, *ll::_1, seq));
+      return make_tuple (false, true, old);
+    }
+}
+
+bool
+FullState::remove (NameInfoConstPtr info)
+{
+  m_lastUpdated = ndn::time::now();
+
+  m_digest.reset ();
+
+  LeafContainer::iterator item = m_leaves.find (info);
+  if (item != m_leaves.end ())
+    {
+      m_leaves.erase (item);
+      return true;
+    }
+  else
+    return false;
+}
+
+} // Sync