diff --git a/tests/identity-fixture.cpp b/tests/identity-fixture.cpp
new file mode 100644
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+++ b/tests/identity-fixture.cpp
@@ -0,0 +1,99 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014  University of Memphis,
+ *                     Regents of the University of California
+ *
+ * This file is part of NLSR (Named-data Link State Routing).
+ * See AUTHORS.md for complete list of NLSR authors and contributors.
+ *
+ * NLSR 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.
+ *
+ * NLSR 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
+ * NLSR, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ **/
+ /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2014 Regents of the University of California.
+ *
+ * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
+ *
+ * ndn-cxx library is free software: you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free Software
+ * Foundation, either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-cxx library 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 Lesser General Public License for more details.
+ *
+ * You should have received copies of the GNU General Public License and GNU Lesser
+ * General Public License along with ndn-cxx, e.g., in COPYING.md file.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * See AUTHORS.md for complete list of ndn-cxx authors and contributors.
+ */
+
+#include <ndn-cxx/security/key-chain.hpp>
+
+#include "boost-test.hpp"
+
+namespace nlsr {
+
+// OSX KeyChain, when used on a headless server,
+// forbids usage of a private key if that key isn't created by the calling process.
+// Therefore, unit testing must create its own key pair.
+
+class IdentityFixture
+{
+public:
+  IdentityFixture()
+  {
+    // save the old default identity
+    try {
+      m_oldDefaultIdentity = m_keyChain.getDefaultIdentity();
+      m_hasOldDefaultIdentity = true;
+    }
+    catch (ndn::SecPublicInfo::Error& e) {
+      m_hasOldDefaultIdentity = false;
+    }
+
+    m_newIdentity.set("/nlsr-test-identity");
+    m_newIdentity.appendVersion();
+
+    // create the new identity and self-signed certificate
+    m_keyChain.createIdentity(m_newIdentity);
+
+    // set the new identity as default identity,
+    // and the corresponding certificate becomes the default certificate
+    m_keyChain.setDefaultIdentity(m_newIdentity);
+  }
+
+  ~IdentityFixture()
+  {
+    // recover the old default setting
+    if (m_hasOldDefaultIdentity) {
+      m_keyChain.setDefaultIdentity(m_oldDefaultIdentity);
+    }
+
+    // remove the temporarily created identity and certificates
+    // XXX This has no effect if oldDefaultIdentity doesn't exist.
+    //     newIdentity would be kept as default.
+    m_keyChain.deleteIdentity(m_newIdentity);
+  }
+
+private:
+  ndn::KeyChain m_keyChain;
+  bool m_hasOldDefaultIdentity;
+  ndn::Name m_oldDefaultIdentity;
+  ndn::Name m_newIdentity;
+};
+
+BOOST_GLOBAL_FIXTURE(IdentityFixture)
+
+} // namespace nlsr
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