diff --git a/src/security/pib/key.cpp b/src/security/pib/key.cpp
index 0d45140..3d7b83c 100644
--- a/src/security/pib/key.cpp
+++ b/src/security/pib/key.cpp
@@ -1,5 +1,5 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
+/*
  * Copyright (c) 2013-2017 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
@@ -140,7 +140,7 @@
 bool
 isValidKeyName(const Name& keyName)
 {
-  return (keyName.size() > Certificate::MIN_KEY_NAME_LENGTH &&
+  return (keyName.size() >= Certificate::MIN_KEY_NAME_LENGTH &&
           keyName.get(-Certificate::MIN_KEY_NAME_LENGTH) == Certificate::KEY_COMPONENT);
 }
 
diff --git a/tests/unit-tests/security/pib/key.t.cpp b/tests/unit-tests/security/pib/key.t.cpp
index afa65e7..2275c2e 100644
--- a/tests/unit-tests/security/pib/key.t.cpp
+++ b/tests/unit-tests/security/pib/key.t.cpp
@@ -1,5 +1,5 @@
 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
-/**
+/*
  * Copyright (c) 2013-2017 Regents of the University of California.
  *
  * This file is part of ndn-cxx library (NDN C++ library with eXperimental eXtensions).
@@ -89,6 +89,24 @@
   BOOST_CHECK_NO_THROW(key2.getDefaultCertificate());
 }
 
+BOOST_AUTO_TEST_CASE(Helpers)
+{
+  BOOST_CHECK_EQUAL(v2::constructKeyName("/hello", name::Component("world")), "/hello/KEY/world");
+
+  BOOST_CHECK_EQUAL(v2::isValidKeyName("/hello"), false);
+  BOOST_CHECK_EQUAL(v2::isValidKeyName("/hello/KEY"), false);
+  BOOST_CHECK_EQUAL(v2::isValidKeyName("/hello/KEY/world"), true);
+
+  BOOST_CHECK_EQUAL(v2::isValidKeyName("/KEY/hello"), true);
+  BOOST_CHECK_EQUAL(v2::isValidKeyName("/hello/world/KEY/!"), true);
+
+  BOOST_CHECK_EQUAL(v2::extractIdentityFromKeyName("/KEY/hello"), "/");
+  BOOST_CHECK_EQUAL(v2::extractIdentityFromKeyName("/hello/KEY/world"), "/hello");
+  BOOST_CHECK_EQUAL(v2::extractIdentityFromKeyName("/hello/world/KEY/!"), "/hello/world");
+
+  BOOST_CHECK_THROW(v2::extractIdentityFromKeyName("/hello"), std::invalid_argument);
+}
+
 BOOST_AUTO_TEST_SUITE_END() // TestKey
 BOOST_AUTO_TEST_SUITE_END() // Pib
 BOOST_AUTO_TEST_SUITE_END() // Security