diff --git a/src/security/validator.hpp b/src/security/validator.hpp
index 5147dd7..2b55782 100644
--- a/src/security/validator.hpp
+++ b/src/security/validator.hpp
@@ -20,39 +20,56 @@
 
 namespace ndn {
 /**
- * Validator is one of the main classes of the security library.
+ * @brief Validator is one of the main classes of the security library.
  *
  * The Validator class provides the interfaces for packet validation.
  */
 class Validator {
 public:
-  struct Error : public std::runtime_error { Error(const std::string &what) : std::runtime_error(what) {} };
+  class Error : public std::runtime_error
+  {
+  public:
+    explicit
+    Error(const std::string& what)
+      : std::runtime_error(what)
+    {
+    }
+  };
 
-  static const shared_ptr<Face> DefaultFace;
+  static const shared_ptr<Face> DEFAULT_FACE;
 
-  Validator (shared_ptr<Face> face = DefaultFace);
+  explicit
+  Validator(shared_ptr<Face> face = DEFAULT_FACE);
 
   /**
-   * @brief Validate Data and call either onValidated or onValidationFailed. 
-   * 
+   * @brief Validate Data and call either onValidated or onValidationFailed.
+   *
    * @param data The Data with the signature to check.
    * @param onValidated If the Data is validated, this calls onValidated(data).
    * @param onValidationFailed If the Data validation fails, this calls onValidationFailed(data).
    */
   void
-  validate (const Data& data, const OnDataValidated &onValidated, const OnDataValidationFailed &onValidationFailed)
-  { validate (data, onValidated, onValidationFailed, 0); }
+  validate(const Data& data,
+           const OnDataValidated& onValidated,
+           const OnDataValidationFailed& onValidationFailed)
+  {
+    validate(data, onValidated, onValidationFailed, 0);
+  }
 
   /**
-   * @brief Validate Interest and call either onValidated or onValidationFailed. 
-   * 
+   * @brief Validate Interest and call either onValidated or onValidationFailed.
+   *
    * @param interest The Interest with the signature to check.
    * @param onValidated If the Interest is validated, this calls onValidated(interest).
    * @param onValidationFailed If the Interest validation fails, this calls onValidationFailed(interest).
    */
   void
-  validate (const Interest& interest, const OnInterestValidated &onValidated, const OnInterestValidationFailed &onValidationFailed)
-  { validate (interest, onValidated, onValidationFailed, 0); }
+  validate(const Interest& interest,
+           const OnInterestValidated& onValidated,
+           const OnInterestValidationFailed& onValidationFailed)
+  {
+    validate(interest, onValidated, onValidationFailed, 0);
+  }
 
   /*****************************************
    *      verifySignature method set       *
@@ -60,53 +77,109 @@
 
   /// @brief Verify the data using the publicKey.
   static bool
-  verifySignature (const Data& data, const PublicKey& publicKey);
+  verifySignature(const Data& data, const PublicKey& publicKey);
 
-  /// @brief Verify the signed Interest using the publicKey.
+  /**
+   * @brief Verify the signed Interest using the publicKey.
+   *
+   * (Note the signature covers the first n-2 name components).
+   */
   static bool
-  verifySignature (const Interest& interest, const PublicKey& publicKey);
+  verifySignature(const Interest& interest, const PublicKey& publicKey);
 
   /// @brief Verify the blob using the publicKey against the signature.
   static bool
-  verifySignature (const Buffer& blob, const Signature& sig, const PublicKey& publicKey);
+  verifySignature(const Buffer& blob, const Signature& sig, const PublicKey& publicKey);
 
   /// @brief Verify the data using the publicKey against the SHA256-RSA signature.
   static bool
-  verifySignature (const Data& data, const SignatureSha256WithRsa& sig, const PublicKey& publicKey)
-  { return verifySignature (data.wireEncode().value(), 
-                            data.wireEncode().value_size() - data.getSignature().getValue().size(), 
-                            sig, publicKey); }
+  verifySignature(const Data& data,
+                  const SignatureSha256WithRsa& sig,
+                  const PublicKey& publicKey)
+  {
+    return verifySignature(data.wireEncode().value(),
+                           data.wireEncode().value_size() - data.getSignature().getValue().size(),
+                           sig, publicKey);
+  }
+
+  /** @brief Verify the interest using the publicKey against the SHA256-RSA signature.
+   *
+   * (Note the signature covers the first n-2 name components).
+   */
+  static bool
+  verifySignature(const Interest& interest,
+                  const SignatureSha256WithRsa& sig,
+                  const PublicKey& publicKey)
+  {
+    if (interest.getName().size() < 2)
+      return false;
+
+    Name signedName = interest.getName().getPrefix(-2);
+
+    return verifySignature(signedName.wireEncode().value(),
+                           signedName.wireEncode().value_size(),
+                           sig, publicKey);
+  }
 
   /// @brief Verify the blob using the publicKey against the SHA256-RSA signature.
   static bool
-  verifySignature (const Buffer& blob, const SignatureSha256WithRsa& sig, const PublicKey& publicKey)
-  { return verifySignature (blob.buf(), blob.size(), sig, publicKey); }
-  
+  verifySignature(const Buffer& blob,
+                  const SignatureSha256WithRsa& sig,
+                  const PublicKey& publicKey)
+  {
+    return verifySignature(blob.buf(), blob.size(), sig, publicKey);
+  }
+
   /// @brief Verify the blob using the publicKey against the SHA256-RSA signature.
   static bool
-  verifySignature (const uint8_t* buf, const size_t size, const SignatureSha256WithRsa &sig, const PublicKey &publicKey);
+  verifySignature(const uint8_t* buf,
+                  const size_t size,
+                  const SignatureSha256WithRsa& sig,
+                  const PublicKey& publicKey);
 
 
   /// @brief Verify the data against the SHA256 signature.
   static bool
-  verifySignature (const Data& data, const SignatureSha256& sig)
-  { return verifySignature (data.wireEncode().value(), 
-                            data.wireEncode().value_size() - data.getSignature().getValue().size(), 
-                            sig); }
+  verifySignature(const Data& data, const SignatureSha256& sig)
+  {
+    return verifySignature(data.wireEncode().value(),
+                           data.wireEncode().value_size() -
+                           data.getSignature().getValue().size(),
+                           sig);
+  }
+
+  /** @brief Verify the interest against the SHA256 signature.
+   *
+   * (Note the signature covers the first n-2 name components).
+   */
+  static bool
+  verifySignature(const Interest& interest, const SignatureSha256& sig)
+  {
+    if (interest.getName().size() < 2)
+      return false;
+
+    Name signedName = interest.getName().getPrefix(-2);
+
+    return verifySignature(signedName.wireEncode().value(),
+                           signedName.wireEncode().value_size(),
+                           sig);
+  }
 
   /// @brief Verify the blob against the SHA256 signature.
   static bool
-  verifySignature (const Buffer& blob, const SignatureSha256& sig)
-  { return verifySignature (blob.buf(), blob.size(), sig); }
-  
+  verifySignature(const Buffer& blob, const SignatureSha256& sig)
+  {
+    return verifySignature (blob.buf(), blob.size(), sig);
+  }
+
   /// @brief Verify the blob against the SHA256 signature.
   static bool
-  verifySignature (const uint8_t* buf, const size_t size, const SignatureSha256& sig);
+  verifySignature(const uint8_t* buf, const size_t size, const SignatureSha256& sig);
 
 
 protected:
   /**
-   * @brief Check the Data against validation policy and return the next validation step if necessary.
+   * @brief Check the Data against policy and return the next validation step if necessary.
    *
    * If there is no next validation step, that validation MUST have been done.
    * i.e., either onValidated or onValidationFailed callback is invoked.
@@ -118,11 +191,11 @@
    * @param nextSteps On return, contains the next validation step.
    */
   virtual void
-  checkPolicy (const Data& data, 
-               int stepCount, 
-               const OnDataValidated &onValidated, 
-               const OnDataValidationFailed &onValidationFailed,
-               std::vector<shared_ptr<ValidationRequest> > &nextSteps) = 0;
+  checkPolicy(const Data& data,
+              int stepCount,
+              const OnDataValidated& onValidated,
+              const OnDataValidationFailed& onValidationFailed,
+              std::vector<shared_ptr<ValidationRequest> >& nextSteps) = 0;
 
   /**
    * @brief Check the Interest against validation policy and return the next validation step if necessary.
@@ -137,39 +210,39 @@
    * @return the indication of next validation step, null if there is no further step.
    */
   virtual void
-  checkPolicy (const Interest& interest, 
-               int stepCount, 
-               const OnInterestValidated &onValidated, 
-               const OnInterestValidationFailed &onValidationFailed,
-               std::vector<shared_ptr<ValidationRequest> > &nextSteps) = 0;
+  checkPolicy(const Interest& interest,
+              int stepCount,
+              const OnInterestValidated& onValidated,
+              const OnInterestValidationFailed& onValidationFailed,
+              std::vector<shared_ptr<ValidationRequest> >& nextSteps) = 0;
 
 private:
   typedef function< void (const std::string&) > OnFailure;
-  
+
   /// @brief Process the received certificate.
   void
-  onData (const Interest& interest, 
-          Data& data, 
-          const shared_ptr<ValidationRequest>& nextStep);
-  
+  onData(const Interest& interest,
+         const Data& data,
+         const shared_ptr<ValidationRequest>& nextStep);
+
   /// @brief Re-express the interest if it times out.
   void
-  onTimeout (const Interest& interest, 
-             int retry, 
-             const OnFailure &onFailure, 
-             const shared_ptr<ValidationRequest>& nextStep);
+  onTimeout(const Interest& interest,
+            int retry,
+            const OnFailure& onFailure,
+            const shared_ptr<ValidationRequest>& nextStep);
 
   void
-  validate (const Data& data, 
-            const OnDataValidated &onValidated, 
-            const OnDataValidationFailed &onValidationFailed, 
-            int stepCount);
+  validate(const Data& data,
+           const OnDataValidated& onValidated,
+           const OnDataValidationFailed& onValidationFailed,
+           int stepCount);
 
   void
-  validate (const Interest& interest, 
-            const OnInterestValidated &onValidated, 
-            const OnInterestValidationFailed &onValidationFailed, 
-            int stepCount);
+  validate(const Interest& interest,
+           const OnInterestValidated& onValidated,
+           const OnInterestValidationFailed& onValidationFailed,
+           int stepCount);
 
 protected:
   shared_ptr<Face> m_face;