diff --git a/include/ndn-cpp/security/identity/sec-public-info.hpp b/include/ndn-cpp/security/identity/sec-public-info.hpp
new file mode 100644
index 0000000..3a46310
--- /dev/null
+++ b/include/ndn-cpp/security/identity/sec-public-info.hpp
@@ -0,0 +1,362 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/**
+ * Copyright (C) 2013 Regents of the University of California.
+ * @author: Yingdi Yu <yingdi@cs.ucla.edu>
+ * @author: Jeff Thompson <jefft0@remap.ucla.edu>
+ * See COPYING for copyright and distribution information.
+ */
+
+#ifndef NDN_SEC_PUBLIC_INFO_HPP
+#define NDN_SEC_PUBLIC_INFO_HPP
+
+#include "../../name.hpp"
+#include "../security-common.hpp"
+#include "../certificate/public-key.hpp"
+#include "../certificate/identity-certificate.hpp"
+
+namespace ndn {
+
+/**
+ * SecPublicInfo is a base class for the storage of identity, public keys and certificates. 
+ * Private keys are stored in SecTpm.
+ * This is an abstract base class.  A subclass must implement the methods.
+ */
+class SecPublicInfo {
+public:
+  struct Error : public std::runtime_error { Error(const std::string &what) : std::runtime_error(what) {} };
+
+  /**
+   * The virtual Destructor.
+   */
+  virtual 
+  ~SecPublicInfo() {}
+
+  /**
+   * Check if the specified identity already exists.
+   * @param identityName The identity name.
+   * @return true if the identity exists, otherwise false.
+   */
+  virtual bool 
+  doesIdentityExist(const Name& identityName) = 0;
+
+  /**
+   * Add a new identity. An exception will be thrown if the identity already exists.
+   * @param identityName The identity name to be added.
+   */
+  virtual void
+  addIdentity(const Name& identityName) = 0;
+
+  /**
+   * Revoke the identity.
+   * @return true if the identity was revoked, false if not.
+   */
+  virtual bool 
+  revokeIdentity() = 0;
+
+  /**
+   * Check if the specified key already exists.
+   * @param keyName The name of the key.
+   * @return true if the key exists, otherwise false.
+   */
+  virtual bool 
+  doesPublicKeyExist(const Name& keyName) = 0;
+
+  /**
+   * Add a public key to the identity storage.
+   * @param keyName The name of the public key to be added.
+   * @param keyType Type of the public key to be added.
+   * @param publicKeyDer A blob of the public key DER to be added.
+   */
+  virtual void 
+  addPublicKey(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 ptr_lib::shared_ptr<PublicKey>
+  getPublicKey(const Name& keyName) = 0;
+
+  /**
+   * Activate a key.  If a key is marked as inactive, its private part will not be used in packet signing.
+   * @param keyName name of the key
+   */
+  virtual void 
+  activatePublicKey(const Name& keyName) = 0;
+
+  /**
+   * Deactivate a key. If a key is marked as inactive, its private part will not be used in packet signing.
+   * @param keyName name of the key
+   */
+  virtual void 
+  deactivatePublicKey(const Name& keyName) = 0;
+
+  /**
+   * Check if the specified certificate already exists.
+   * @param certificateName The name of the certificate.
+   * @return true if the certificate exists, otherwise false.
+   */
+  virtual bool
+  doesCertificateExist(const Name& certificateName) = 0;
+
+  /**
+   * Add a certificate to the identity storage.
+   * @param certificate The certificate to be added.  This makes a copy of the certificate.
+   */
+  virtual void 
+  addCertificate(const IdentityCertificate& certificate) = 0;
+
+  /**
+   * Get a certificate from the identity storage.
+   * @param certificateName The name of the requested certificate.
+   * @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<IdentityCertificate> 
+  getCertificate(const Name &certificateName, bool allowAny = false) = 0;
+
+
+  /*****************************************
+   *            Default Getter             *
+   *****************************************/
+
+  /**
+   * Get the default identity. 
+   * @param return The name of default identity, or an empty name if there is no default.
+   */
+  virtual Name 
+  getDefaultIdentity() = 0;
+
+  /**
+   * Get the default key name for the specified identity.
+   * @param identityName The identity name.
+   * @return The default key name.
+   */
+  virtual Name 
+  getDefaultKeyNameForIdentity(const Name& identityName) = 0;
+
+  /**
+   * Get the default certificate name for the specified key.
+   * @param keyName The key name.
+   * @return The default certificate name.
+   */
+  virtual Name 
+  getDefaultCertificateNameForKey(const Name& keyName) = 0;
+
+  virtual std::vector<Name>
+  getAllIdentities(bool isDefault) = 0;
+
+  virtual std::vector<Name>
+  getAllKeyNames(bool isDefault) = 0;
+
+  virtual std::vector<Name>
+  getAllKeyNamesOfIdentity(const Name& identity, bool isDefault) = 0;
+    
+  virtual std::vector<Name>
+  getAllCertificateNames(bool isDefault) = 0;
+    
+  virtual std::vector<Name>
+  getAllCertificateNamesOfKey(const Name& keyName, bool isDefault) = 0;
+
+protected:
+
+  /*****************************************
+   *            Default Setter             *
+   *****************************************/
+  
+  /**
+   * Set the default identity.  If the identityName does not exist, then clear the default identity
+   * so that getDefaultIdentity() returns an empty name.
+   * @param identityName The default identity name.
+   */
+  virtual void 
+  setDefaultIdentityInternal(const Name& identityName) = 0;
+  
+  /**
+   * Set the default key name for the corresponding identity.
+   * @param keyName The key name.
+   */
+  virtual void
+  setDefaultKeyNameForIdentityInternal(const Name& keyName) = 0;
+
+  /**
+   * Set the default certificate name for the corresponding key.
+   * @param certificateName The certificate name.
+   */
+  virtual void 
+  setDefaultCertificateNameForKeyInternal(const Name& certificateName) = 0; 
+
+public:
+  
+  /*****************************************
+   *            Helper Methods             *
+   *****************************************/
+
+  /**
+   * Set the default identity.  If the identityName does not exist, then clear the default identity
+   * so that getDefaultIdentity() returns an empty name.
+   * @param identityName The default identity name.
+   */
+  inline void 
+  setDefaultIdentity(const Name& identityName);
+
+  /**
+   * Set the default key name for the corresponding identity.
+   * @param keyName The key name.
+   */
+  inline void 
+  setDefaultKeyNameForIdentity(const Name& keyName);
+
+  /**
+   * Set the default certificate name for the corresponding key.
+   * @param certificateName The certificate name.
+   */
+  inline void 
+  setDefaultCertificateNameForKey(const Name& certificateName); 
+
+  /**
+   * Generate a name for a new key belonging to the identity.
+   * @param identityName The identity name.
+   * @param useKsk If true, generate a KSK name, otherwise a DSK name.
+   * @return The generated key name.
+   */
+  inline Name 
+  getNewKeyName(const Name& identityName, bool useKsk);
+
+    /**
+   * Get the default certificate name for the specified identity.
+   * @param identityName The identity name.
+   * @return The default certificate name.
+   */
+  inline Name 
+  getDefaultCertificateNameForIdentity(const Name& identityName);
+
+  /**
+   * Get the default certificate name of the default identity, which will be used when signing is based on identity and 
+   * the identity is not specified.
+   * @return The requested certificate name.
+   */
+  inline Name
+  getDefaultCertificateName();
+
+  /**
+   * Add a certificate and set the certificate as the default of its corresponding key.
+   * @param certificate The certificate to be added.  This makes a copy of the certificate.
+   */
+  inline void
+  addCertificateAsKeyDefault(const IdentityCertificate& certificate);
+
+  /**
+   * Add a certificate into the public key identity storage and set the certificate as the default for its corresponding identity.
+   * @param certificate The certificate to be added.  This makes a copy of the certificate.
+   */
+  inline void
+  addCertificateAsIdentityDefault(const IdentityCertificate& certificate);
+
+  inline ptr_lib::shared_ptr<IdentityCertificate>
+  defaultCertificate();
+  
+  inline void
+  refreshDefaultCertificate();
+
+protected:
+  ptr_lib::shared_ptr<IdentityCertificate> defaultCertificate_;
+
+};
+
+void
+SecPublicInfo::setDefaultIdentity(const Name& identityName)
+{
+  setDefaultIdentityInternal(identityName);
+  refreshDefaultCertificate();
+}
+
+void
+SecPublicInfo::setDefaultKeyNameForIdentity(const Name& keyName)
+{
+  setDefaultKeyNameForIdentityInternal(keyName);
+  refreshDefaultCertificate();
+}
+
+void 
+SecPublicInfo::setDefaultCertificateNameForKey(const Name& certificateName)
+{
+  setDefaultCertificateNameForKeyInternal(certificateName);
+  refreshDefaultCertificate();
+}
+
+Name 
+SecPublicInfo::getDefaultCertificateNameForIdentity(const Name& identityName)
+{
+  return getDefaultCertificateNameForKey(getDefaultKeyNameForIdentity(identityName));
+}
+
+Name
+SecPublicInfo::getNewKeyName (const Name& identityName, bool useKsk)
+{
+  MillisecondsSince1970 ti = getNow();
+  // Get the number of seconds.
+  std::ostringstream oss;
+  oss << floor(ti / 1000.0);  
+
+  std::string keyIdStr;
+    
+  if (useKsk)
+    keyIdStr = ("KSK-" + oss.str());
+  else
+    keyIdStr = ("DSK-" + oss.str());
+
+  Name keyName = Name(identityName).append(keyIdStr);
+
+  if (doesPublicKeyExist(keyName))
+    throw Error("Key name already exists");
+
+  return keyName;
+}
+
+Name
+SecPublicInfo::getDefaultCertificateName()
+{
+  if(!static_cast<bool>(defaultCertificate_))
+    refreshDefaultCertificate();
+
+  if(!static_cast<bool>(defaultCertificate_))
+    return Name();
+
+  return defaultCertificate_->getName();
+}
+
+void
+SecPublicInfo::addCertificateAsKeyDefault(const IdentityCertificate& certificate)
+{
+  addCertificate(certificate);
+  setDefaultCertificateNameForKeyInternal(certificate.getName());
+  refreshDefaultCertificate();
+}
+
+void
+SecPublicInfo::addCertificateAsIdentityDefault(const IdentityCertificate& certificate)
+{
+  addCertificate(certificate);
+  setDefaultKeyNameForIdentityInternal(certificate.getPublicKeyName());
+  setDefaultCertificateNameForKeyInternal(certificate.getName());
+  refreshDefaultCertificate();
+}
+
+ptr_lib::shared_ptr<IdentityCertificate>
+SecPublicInfo::defaultCertificate()
+{
+  return defaultCertificate_;
+}
+
+void
+SecPublicInfo::refreshDefaultCertificate()
+{
+  defaultCertificate_ = getCertificate(getDefaultCertificateNameForIdentity(getDefaultIdentity()));
+}
+
+
+}
+
+#endif