diff --git a/include/ndn-cpp/security/certificate/certificate.hpp b/include/ndn-cpp/security/certificate/certificate.hpp
index 0c7323b..c2fd95a 100644
--- a/include/ndn-cpp/security/certificate/certificate.hpp
+++ b/include/ndn-cpp/security/certificate/certificate.hpp
@@ -18,11 +18,13 @@
 
 namespace ndn {
 
-typedef std::vector<CertificateSubjectDescription> SubjectDescriptionList;
-typedef std::vector<CertificateExtension> ExtensionList;
-
 class Certificate : public Data {
 public:
+  struct Error : public std::runtime_error { Error(const std::string &what) : std::runtime_error(what) {} };
+
+  typedef std::vector<CertificateSubjectDescription> SubjectDescriptionList;
+  typedef std::vector<CertificateExtension> ExtensionList;
+
   /**
    * The default constructor.
    */
@@ -40,6 +42,9 @@
   virtual 
   ~Certificate();
 
+  inline void
+  wireDecode(const Block &wire);
+  
   /**
    * encode certificate info into content
    */
@@ -117,7 +122,7 @@
   isTooLate();
 
   void 
-  printCertificate();
+  printCertificate(std::ostream &os) const;
 
 protected:
   void
@@ -131,6 +136,21 @@
   ExtensionList extensionList_;
 };
 
+inline void
+Certificate::wireDecode(const Block &wire)
+{
+  Data::wireDecode(wire);
+  decode();
 }
 
+
+inline std::ostream&
+operator <<(std::ostream &os, const Certificate &cert)
+{
+  cert.printCertificate(os);
+  return os;
+}
+
+} // namespace ndn
+
 #endif
diff --git a/include/ndn-cpp/security/certificate/identity-certificate.hpp b/include/ndn-cpp/security/certificate/identity-certificate.hpp
index 4d3a9db..85c8e72 100644
--- a/include/ndn-cpp/security/certificate/identity-certificate.hpp
+++ b/include/ndn-cpp/security/certificate/identity-certificate.hpp
@@ -16,12 +16,13 @@
 class IdentityCertificate : public Certificate
 {
 public:
+  struct Error : public std::runtime_error { Error(const std::string &what) : std::runtime_error(what) {} };
+
   /**
    * The default constructor.
    */
-  IdentityCertificate()
-  {
-  }
+  inline
+  IdentityCertificate();
 
   // Note: The copy constructor works because publicKeyName_ has a copy constructor.
 
@@ -29,29 +30,20 @@
    * Create an IdentityCertificate from the content in the data packet.
    * @param data The data packet with the content to decode.
    */
+  inline
   IdentityCertificate(const Data& data);
   
   /**
-   * The copy constructor. 
-   */
-  IdentityCertificate(const IdentityCertificate& identityCertificate);
-  
-  /**
    * The virtual destructor.
    */
-  virtual 
+  inline virtual 
   ~IdentityCertificate();
   
-  /**
-   * Override the base class method to check that the name is a valid identity certificate name.
-   * @param name The identity certificate name which is copied.
-   * @return This Data so that you can chain calls to update values.
-   */
-  virtual Data &
-  setName(const Name& name);
-
-  Name 
-  getPublicKeyName () const { return publicKeyName_; }
+  inline void
+  wireDecode(const Block &wire);
+  
+  inline const Name &
+  getPublicKeyName () const;
 
   static bool
   isIdentityCertificate(const Certificate& certificate);
@@ -75,6 +67,36 @@
   Name publicKeyName_;
 };
 
+inline
+IdentityCertificate::IdentityCertificate()
+{
+}
+
+inline
+IdentityCertificate::IdentityCertificate(const Data& data)
+  : Certificate(data)
+{
+  setPublicKeyName();
+}
+  
+inline
+IdentityCertificate::~IdentityCertificate()
+{
+}
+
+inline void
+IdentityCertificate::wireDecode(const Block &wire)
+{
+  Certificate::wireDecode(wire);
+  setPublicKeyName();
+}
+
+inline const Name &
+IdentityCertificate::getPublicKeyName () const
+{
+  return publicKeyName_;
+}
+
 }
 
 #endif
diff --git a/include/ndn-cpp/security/certificate/public-key.hpp b/include/ndn-cpp/security/certificate/public-key.hpp
index 43e1223..1fac1ec 100644
--- a/include/ndn-cpp/security/certificate/public-key.hpp
+++ b/include/ndn-cpp/security/certificate/public-key.hpp
@@ -33,13 +33,13 @@
    */
   PublicKey(const uint8_t *keyDerBuf, size_t keyDerSize);
 
-  const Buffer&
+  inline const Buffer&
   get() const
   {
     return key_;
   }
 
-  void
+  inline void
   set(const uint8_t *keyDerBuf, size_t keyDerSize)
   {
     Buffer buf(keyDerBuf, keyDerSize);
@@ -59,6 +59,18 @@
   // Blob 
   // getDigest(DigestAlgorithm digestAlgorithm = DIGEST_ALGORITHM_SHA256) const;
 
+  inline bool
+  operator ==(const PublicKey &key) const
+  {
+    return key_ == key.key_;
+  }
+
+  inline bool
+  operator !=(const PublicKey &key) const
+  {
+    return key_ != key.key_;
+  }
+  
 private:
   Buffer key_;
 };
diff --git a/include/ndn-cpp/security/identity/basic-identity-storage.hpp b/include/ndn-cpp/security/identity/basic-identity-storage.hpp
index 4954f01..0dc3e5d 100644
--- a/include/ndn-cpp/security/identity/basic-identity-storage.hpp
+++ b/include/ndn-cpp/security/identity/basic-identity-storage.hpp
@@ -26,6 +26,8 @@
  */
 class BasicIdentityStorage : public IdentityStorage {
 public:
+  struct Error : public IdentityStorage::Error { Error(const std::string &what) : IdentityStorage::Error(what) {} };
+
   BasicIdentityStorage();
   
   /**
@@ -34,6 +36,7 @@
   virtual 
   ~BasicIdentityStorage();
 
+  // from IdentityStorage
   /**
    * Check if the specified identity already exists.
    * @param identityName The identity name.
@@ -71,14 +74,14 @@
    * @param publicKeyDer A blob of the public key DER to be added.
    */
   virtual void 
-  addKey(const Name& keyName, KeyType keyType, const Blob& publicKeyDer);
+  addKey(const Name& keyName, KeyType keyType, const PublicKey& publicKeyDer);
 
   /**
    * Get the public key DER blob from the identity storage.
    * @param keyName The name of the requested public key.
    * @return The DER Blob.  If not found, return a Blob with a null pointer.
    */
-  virtual Blob
+  virtual ptr_lib::shared_ptr<PublicKey>
   getKey(const Name& keyName);
 
   /**
@@ -123,7 +126,7 @@
    * @param allowAny If false, only a valid certificate will be returned, otherwise validity is disregarded.
    * @return The requested certificate.  If not found, return a shared_ptr with a null pointer.
    */
-  virtual ptr_lib::shared_ptr<Data> 
+  virtual ptr_lib::shared_ptr<IdentityCertificate> 
   getCertificate(const Name &certificateName, bool allowAny = false);
 
 
diff --git a/include/ndn-cpp/security/identity/identity-manager.hpp b/include/ndn-cpp/security/identity/identity-manager.hpp
index 4273f6b..702ad1f 100644
--- a/include/ndn-cpp/security/identity/identity-manager.hpp
+++ b/include/ndn-cpp/security/identity/identity-manager.hpp
@@ -11,6 +11,7 @@
 
 #include "identity-storage.hpp"
 #include "private-key-storage.hpp"
+#include "../certificate/public-key.hpp"
 
 #include "../../data.hpp"
 
@@ -25,10 +26,20 @@
 public:
   struct Error : public std::runtime_error { Error(const std::string &what) : std::runtime_error(what) {} };
 
-  IdentityManager(const ptr_lib::shared_ptr<IdentityStorage>& identityStorage, const ptr_lib::shared_ptr<PrivateKeyStorage>& privateKeyStorage)
-  : identityStorage_(identityStorage), privateKeyStorage_(privateKeyStorage)
-  {
-  }
+  IdentityManager(const ptr_lib::shared_ptr<IdentityStorage>   &identityStorage   = DefaultIdentityStorage,
+                  const ptr_lib::shared_ptr<PrivateKeyStorage> &privateKeyStorage = DefaultPrivateKeyStorage);
+
+  inline IdentityStorage&
+  info();
+
+  inline const IdentityStorage&
+  info() const;
+
+  inline PrivateKeyStorage&
+  tpm();
+
+  inline const PrivateKeyStorage&
+  tpm() const;
   
   /**
    * Create an identity by creating a pair of Key-Signing-Key (KSK) for this identity and a self-signed certificate of the KSK.
@@ -45,7 +56,7 @@
   Name
   getDefaultIdentity()
   {
-    return identityStorage_->getDefaultIdentity();
+    return info().getDefaultIdentity();
   }
 
   /**
@@ -66,7 +77,7 @@
   void
   setDefaultKeyForIdentity(const Name& keyName, const Name& identityName = Name())
   {
-    identityStorage_->setDefaultKeyNameForIdentity(keyName, identityName);
+    info().setDefaultKeyNameForIdentity(keyName, identityName);
   }
 
   /**
@@ -77,7 +88,7 @@
   Name
   getDefaultKeyNameForIdentity(const Name& identityName = Name())
   {
-    return identityStorage_->getDefaultKeyNameForIdentity(identityName);
+    return info().getDefaultKeyNameForIdentity(identityName);
   }
   
   /**
@@ -95,11 +106,11 @@
    * @param keyName The name of the key.
    * @return The public key.
    */
-  // ptr_lib::shared_ptr<PublicKey>
-  // getPublicKey(const Name& keyName)
-  // {
-  //   return PublicKey::fromDer(identityStorage_->getKey(keyName));
-  // }
+  ptr_lib::shared_ptr<PublicKey>
+  getPublicKey(const Name& keyName)
+  {
+    return info().getKey(keyName);
+  }
 
   /**
    * Create an identity certificate for a public key managed by this IdentityManager.
@@ -109,9 +120,11 @@
    * @param notAfter The notAfter vallue in validity field of the generated certificate.
    * @return The name of generated identity certificate.
    */
-  Name
+  ptr_lib::shared_ptr<IdentityCertificate>
   createIdentityCertificate
-    (const Name& certificatePrefix, const Name& signerCertificateName, const MillisecondsSince1970& notBefore, 
+    (const Name& certificatePrefix,
+     const Name& signerCertificateName,
+     const MillisecondsSince1970& notBefore, 
      const MillisecondsSince1970& notAfter);
 
   /**
@@ -125,8 +138,11 @@
    */
   ptr_lib::shared_ptr<IdentityCertificate>
   createIdentityCertificate
-    (const Name& certificatePrefix, const PublicKey& publickey, const Name& signerCertificateName, 
-     const MillisecondsSince1970& notBefore, const MillisecondsSince1970& notAfter); 
+    (const Name& certificatePrefix,
+     const PublicKey& publickey,
+     const Name& signerCertificateName, 
+     const MillisecondsSince1970& notBefore,
+     const MillisecondsSince1970& notAfter); 
     
   /**
    * Add a certificate into the public key identity storage.
@@ -135,7 +151,7 @@
   void
   addCertificate(const IdentityCertificate& certificate)
   {
-    identityStorage_->addCertificate(certificate);
+    info().addCertificate(certificate);
   }
 
   /**
@@ -164,22 +180,22 @@
    * @param certificateName The name of the requested certificate.
    * @return the requested certificate which is valid.
    */
-  // ptr_lib::shared_ptr<IdentityCertificate>
-  // getCertificate(const Name& certificateName)
-  // {
-  //   return ptr_lib::make_shared<IdentityCertificate>(*identityStorage_->getCertificate(certificateName, false));
-  // }
+  ptr_lib::shared_ptr<IdentityCertificate>
+  getCertificate(const Name& certificateName)
+  {
+    return info().getCertificate(certificateName, false);
+  }
     
   /**
    * Get a certificate even if the certificate is not valid anymore.
    * @param certificateName The name of the requested certificate.
    * @return the requested certificate.
    */
-  // ptr_lib::shared_ptr<IdentityCertificate>
-  // getAnyCertificate(const Name& certificateName)
-  // {
-  //   return ptr_lib::make_shared<IdentityCertificate>(*identityStorage_->getCertificate(certificateName, true));
-  // }
+  ptr_lib::shared_ptr<IdentityCertificate>
+  getAnyCertificate(const Name& certificateName)
+  {
+    return info().getCertificate(certificateName, true);
+  }
     
   /**
    * Get the default certificate name for the specified identity, which will be used when signing is performed based on identity.
@@ -189,7 +205,7 @@
   Name
   getDefaultCertificateNameForIdentity(const Name& identityName)
   {
-    return identityStorage_->getDefaultCertificateNameForIdentity(identityName);
+    return info().getDefaultCertificateNameForIdentity(identityName);
   }
     
   /**
@@ -200,7 +216,7 @@
   Name
   getDefaultCertificateName()
   {
-    return identityStorage_->getDefaultCertificateNameForIdentity(getDefaultIdentity());
+    return info().getDefaultCertificateNameForIdentity(getDefaultIdentity());
   }
         
   /**
@@ -231,6 +247,16 @@
    */
   ptr_lib::shared_ptr<IdentityCertificate>
   selfSign(const Name& keyName);
+
+  /**
+   * @brief Self-sign the supplied identity certificate
+   */
+  void
+  selfSign (IdentityCertificate& cert);
+  
+public:
+  static const ptr_lib::shared_ptr<IdentityStorage>   DefaultIdentityStorage;
+  static const ptr_lib::shared_ptr<PrivateKeyStorage> DefaultPrivateKeyStorage;
   
 private:
   /**
@@ -246,11 +272,49 @@
 
   static Name
   getKeyNameFromCertificatePrefix(const Name& certificatePrefix);
-  
-  ptr_lib::shared_ptr<IdentityStorage> identityStorage_;
+
+private:
+  ptr_lib::shared_ptr<IdentityStorage>   identityStorage_;
   ptr_lib::shared_ptr<PrivateKeyStorage> privateKeyStorage_;
 };
 
+inline IdentityStorage&
+IdentityManager::info()
+{
+  if (!identityStorage_)
+    throw Error("IdentityStorage is not assigned to IdentityManager");
+
+  return *identityStorage_;
+}
+
+inline const IdentityStorage&
+IdentityManager::info() const
+{
+  if (!identityStorage_)
+    throw Error("IdentityStorage is not assigned to IdentityManager");
+  
+  return *identityStorage_;
+}
+
+inline PrivateKeyStorage&
+IdentityManager::tpm()
+{
+  if (!identityStorage_)
+    throw Error("PrivateKeyStorage is not assigned to IdentityManager");
+  
+  return *privateKeyStorage_;
+}
+
+inline const PrivateKeyStorage&
+IdentityManager::tpm() const
+{
+  if (!identityStorage_)
+    throw Error("PrivateKeyStorage is not assigned to IdentityManager");
+  return *privateKeyStorage_;
+}
+  
+  
+
 }
 
 #endif
diff --git a/include/ndn-cpp/security/identity/identity-storage.hpp b/include/ndn-cpp/security/identity/identity-storage.hpp
index 442e522..87d93fd 100644
--- a/include/ndn-cpp/security/identity/identity-storage.hpp
+++ b/include/ndn-cpp/security/identity/identity-storage.hpp
@@ -11,6 +11,7 @@
 
 #include "../../name.hpp"
 #include "../security-common.hpp"
+#include "../certificate/public-key.hpp"
 
 namespace ndn {
 
@@ -79,14 +80,14 @@
    * @param publicKeyDer A blob of the public key DER to be added.
    */
   virtual void 
-  addKey(const Name& keyName, KeyType keyType, const Buffer& publicKeyDer) = 0;
+  addKey(const Name& keyName, KeyType keyType, const PublicKey& publicKeyDer) = 0;
 
   /**
    * Get the public key DER blob from the identity storage.
    * @param keyName The name of the requested public key.
    * @return The DER Blob.  If not found, return a Blob with a null pointer.
    */
-  virtual Buffer
+  virtual ptr_lib::shared_ptr<PublicKey>
   getKey(const Name& keyName) = 0;
 
   /**
@@ -124,7 +125,7 @@
    * @param allowAny If false, only a valid certificate will be returned, otherwise validity is disregarded.
    * @return The requested certificate.  If not found, return a shared_ptr with a null pointer.
    */
-  virtual ptr_lib::shared_ptr<Data> 
+  virtual ptr_lib::shared_ptr<IdentityCertificate> 
   getCertificate(const Name &certificateName, bool allowAny = false) = 0;
 
 
diff --git a/include/ndn-cpp/security/identity/private-key-storage.hpp b/include/ndn-cpp/security/identity/private-key-storage.hpp
index c789d89..29461bb 100644
--- a/include/ndn-cpp/security/identity/private-key-storage.hpp
+++ b/include/ndn-cpp/security/identity/private-key-storage.hpp
@@ -12,6 +12,7 @@
 #include <string>
 #include "../security-common.hpp"
 #include "../../name.hpp"
+#include "../../data.hpp"
 
 namespace ndn {
 
@@ -51,8 +52,15 @@
    * @return The signature, or a null pointer if signing fails.
    */  
   virtual ConstBufferPtr
-  sign(const uint8_t *data, size_t dataLength, const Name& keyName, DigestAlgorithm digestAlgorithm = DIGEST_ALGORITHM_SHA256) = 0;
-    
+  sign(const uint8_t *data, size_t dataLength,
+       const Signature &signature,
+       const Name& keyName, DigestAlgorithm digestAlgorithm = DIGEST_ALGORITHM_SHA256) = 0;
+
+  virtual ConstBufferPtr
+  sign(const Data &data,
+       const Signature &signature,
+       const Name& keyName, DigestAlgorithm digestAlgorithm = DIGEST_ALGORITHM_SHA256) = 0;
+  
   /**
    * Decrypt data.
    * @param keyName The name of the decrypting key.
diff --git a/include/ndn-cpp/security/key-chain.hpp b/include/ndn-cpp/security/key-chain.hpp
index 4e804cc..da470f7 100644
--- a/include/ndn-cpp/security/key-chain.hpp
+++ b/include/ndn-cpp/security/key-chain.hpp
@@ -29,7 +29,9 @@
 public:
   struct Error : public std::runtime_error { Error(const std::string &what) : std::runtime_error(what) {} };
 
-  KeyChain(IdentityManager *identityManager, PolicyManager *policyManager);
+  KeyChain(const ptr_lib::shared_ptr<IdentityManager>   &identityManager   = DefaultIdentityManager,
+           const ptr_lib::shared_ptr<PolicyManager>     &policyManager     = DefaultPolicyManager,
+           const ptr_lib::shared_ptr<EncryptionManager> &encryptionManager = DefaultEncryptionManager);
 
   /**
    * @brief Set the Face which will be used to fetch required certificates.
@@ -47,6 +49,9 @@
   inline IdentityManager&
   identities()
   {
+    if (!identityManager_)
+      throw Error("IdentityManager is not assigned to the KeyChain");
+
     return *identityManager_;
   }
 
@@ -57,10 +62,26 @@
   inline PolicyManager&
   policies()
   {
+    if (!policyManager_)
+      throw Error("PolicyManager is not assigned to the KeyChain");
+
     return *policyManager_;
   }
 
   /*****************************************
+   *         Encryption Management         *
+   *****************************************/
+
+  inline EncryptionManager&
+  encryption()
+  {
+    if (!encryptionManager_)
+      throw Error("EncryptionManager is not assigned to the KeyChain");
+
+    return *encryptionManager_;
+  }
+
+  /*****************************************
    *              Sign/Verify              *
    *****************************************/
 
@@ -70,7 +91,6 @@
    * data.getMetaInfo().setTimestampMilliseconds(time(NULL) * 1000.0).
    * @param data The Data object to be signed.  This updates its signature and key locator field and wireEncoding.
    * @param certificateName The certificate name of the key to use for signing.  If omitted, infer the signing identity from the data packet name.
-   * @param wireFormat A WireFormat object used to encode the input. If omitted, use WireFormat getDefaultWireFormat().
    */
   void 
   sign(Data& data, const Name& certificateName);
@@ -91,7 +111,6 @@
    * data.getMetaInfo().setTimestampMilliseconds(time(NULL) * 1000.0).
    * @param data The Data object to be signed.  This updates its signature and key locator field and wireEncoding.
    * @param identityName The identity name for the key to use for signing.  If omitted, infer the signing identity from the data packet name.
-   * @param wireFormat A WireFormat object used to encode the input. If omitted, use WireFormat getDefaultWireFormat().
    */
   void 
   signByIdentity(Data& data, const Name& identityName = Name());
@@ -122,7 +141,12 @@
    *           Encrypt/Decrypt             *
    *****************************************/
   // todo
-  
+
+public:
+  static const ptr_lib::shared_ptr<IdentityManager>   DefaultIdentityManager;
+  static const ptr_lib::shared_ptr<PolicyManager>     DefaultPolicyManager;
+  static const ptr_lib::shared_ptr<EncryptionManager> DefaultEncryptionManager;
+    
 private:
   void
   onCertificateData
@@ -134,9 +158,10 @@
      const ptr_lib::shared_ptr<Data> &data, ptr_lib::shared_ptr<ValidationRequest> nextStep);
 
 private:
-  std::auto_ptr<IdentityManager>   identityManager_;
-  std::auto_ptr<PolicyManager>     policyManager_;
-  // std::auto_ptr<EncryptionManager> encryptionManager_;
+  ptr_lib::shared_ptr<IdentityManager>   identityManager_;
+  ptr_lib::shared_ptr<PolicyManager>     policyManager_;
+  ptr_lib::shared_ptr<EncryptionManager> encryptionManager_;
+
   ptr_lib::shared_ptr<Face>        face_;
   
   const int maxSteps_;