diff --git a/src/security/sec-tpm-file.hpp b/src/security/sec-tpm-file.hpp
index e934fd7..ed25d2d 100644
--- a/src/security/sec-tpm-file.hpp
+++ b/src/security/sec-tpm-file.hpp
@@ -1,6 +1,6 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
 /**
- * Copyright (c) 2013-2015 Regents of the University of California.
+ * Copyright (c) 2013-2016 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
  *
@@ -31,6 +31,7 @@
 #include "sec-tpm.hpp"
 
 namespace ndn {
+namespace security {
 
 class SecTpmFile : public SecTpm
 {
@@ -91,7 +92,7 @@
   virtual void
   deleteKeyPairInTpm(const Name& keyName);
 
-  virtual shared_ptr<PublicKey>
+  virtual shared_ptr<v1::PublicKey>
   getPublicKeyFromTpm(const Name&  keyName);
 
   virtual Block
@@ -143,6 +144,10 @@
   bool m_inTerminal;
 };
 
+} // namespace security
+
+using security::SecTpmFile;
+
 } // namespace ndn
 
 #endif  // NDN_SECURITY_SEC_TPM_FILE_HPP