diff --git a/src/common.hpp b/src/common.hpp
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+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014,  Regents of the University of California.
+ *
+ * This file is part of NDN repo-ng (Next generation of NDN repository).
+ * See AUTHORS.md for complete list of repo-ng authors and contributors.
+ *
+ * repo-ng is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * repo-ng 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
+ * repo-ng, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef REPO_COMMON_HPP
+#define REPO_COMMON_HPP
+
+#include <ndn-cxx/face.hpp>
+#include <ndn-cxx/interest.hpp>
+#include <ndn-cxx/name.hpp>
+#include <ndn-cxx/data.hpp>
+#include <ndn-cxx/selectors.hpp>
+#include <ndn-cxx/key-locator.hpp>
+#include <ndn-cxx/security/key-chain.hpp>
+#include <ndn-cxx/util/command-interest-validator.hpp>
+#include <ndn-cxx/util/time.hpp>
+#include <ndn-cxx/util/scheduler.hpp>
+
+#include <boost/utility.hpp>
+#include <boost/random/mersenne_twister.hpp>
+#include <boost/random/uniform_int_distribution.hpp>
+
+#include <map>
+#include <string>
+#include <vector>
+#include <algorithm>
+
+namespace repo {
+
+using ndn::Face;
+using ndn::Block;
+using ndn::Name;
+using ndn::Interest;
+using ndn::Selectors;
+using ndn::Exclude;
+using ndn::Data;
+using ndn::KeyLocator;
+using ndn::KeyChain;
+using ndn::CommandInterestValidator;
+using ndn::Scheduler;
+
+using ndn::bind;
+using ndn::shared_ptr;
+using ndn::make_shared;
+using ndn::enable_shared_from_this;
+
+using std::vector;
+using std::string;
+
+using boost::noncopyable;
+
+typedef uint64_t ProcessId;
+typedef uint64_t SegmentNo;
+
+} // namespace repo
+
+#endif // REPO_COMMON_HPP