diff --git a/src/security/tpm/key-handle-mem.cpp b/src/security/tpm/key-handle-mem.cpp
new file mode 100644
index 0000000..00f5b21
--- /dev/null
+++ b/src/security/tpm/key-handle-mem.cpp
@@ -0,0 +1,69 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2013-2016 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 "key-handle-mem.hpp"
+#include "../../encoding/buffer-stream.hpp"
+#include "../transform.hpp"
+#include "../transform/private-key.hpp"
+
+namespace ndn {
+namespace security {
+namespace tpm {
+
+using transform::PrivateKey;
+
+KeyHandleMem::KeyHandleMem(shared_ptr<PrivateKey> key)
+  : m_key(key)
+{
+  BOOST_ASSERT(key != nullptr);
+}
+
+ConstBufferPtr
+KeyHandleMem::doSign(DigestAlgorithm digestAlgorithm, const uint8_t* buf, size_t size) const
+{
+  switch (digestAlgorithm) {
+    case DigestAlgorithm::SHA256: {
+      using namespace transform;
+
+      OBufferStream sigOs;
+      bufferSource(buf, size) >> signerFilter(digestAlgorithm, *m_key) >> streamSink(sigOs);
+      return sigOs.buf();
+    }
+    default:
+      return nullptr;
+  }
+}
+
+ConstBufferPtr
+KeyHandleMem::doDecrypt(const uint8_t* cipherText, size_t cipherTextLen) const
+{
+  return m_key->decrypt(cipherText, cipherTextLen);
+}
+
+ConstBufferPtr
+KeyHandleMem::doDerivePublicKey() const
+{
+  return m_key->derivePublicKey();
+}
+
+} // namespace tpm
+} // namespace security
+} // namespace ndn