diff --git a/tests/unit-tests/security/pib/identity-container.t.cpp b/tests/unit-tests/security/pib/identity-container.t.cpp
index b9af408..92420db 100644
--- a/tests/unit-tests/security/pib/identity-container.t.cpp
+++ b/tests/unit-tests/security/pib/identity-container.t.cpp
@@ -35,23 +35,89 @@
 
 BOOST_AUTO_TEST_SUITE(Security)
 BOOST_AUTO_TEST_SUITE(Pib)
-BOOST_AUTO_TEST_SUITE(TestIdentityContainer)
+BOOST_FIXTURE_TEST_SUITE(TestIdentityContainer, PibDataFixture)
 
 using pib::Pib;
 
-BOOST_FIXTURE_TEST_CASE(Basic, PibDataFixture)
+BOOST_AUTO_TEST_CASE(Basic)
 {
   auto pibImpl = make_shared<PibMemory>();
-  Pib pib("pib-memory", "", pibImpl);
 
-  Identity identity1 = pib.addIdentity(id1);
-  Identity identity2 = pib.addIdentity(id2);
+  // start with an empty container
+  IdentityContainer container(pibImpl);
+  BOOST_CHECK_EQUAL(container.size(), 0);
+  BOOST_CHECK_EQUAL(container.getLoadedIdentities().size(), 0);
 
-  IdentityContainer container = pib.getIdentities();
+  // add the first identity
+  Identity identity11 = container.add(id1);
+  BOOST_CHECK_EQUAL(identity11.getName(), id1);
+  BOOST_CHECK_EQUAL(container.size(), 1);
+  BOOST_CHECK_EQUAL(container.getLoadedIdentities().size(), 1);
+  BOOST_CHECK(container.find(id1) != container.end());
+
+  // add the same identity again
+  Identity identity12 = container.add(id1);
+  BOOST_CHECK_EQUAL(identity12.getName(), id1);
+  BOOST_CHECK_EQUAL(container.size(), 1);
+  BOOST_CHECK_EQUAL(container.getLoadedIdentities().size(), 1);
+  BOOST_CHECK(container.find(id1) != container.end());
+
+  // add the second identity
+  Identity identity21 = container.add(id2);
+  BOOST_CHECK_EQUAL(identity21.getName(), id2);
   BOOST_CHECK_EQUAL(container.size(), 2);
+  BOOST_CHECK_EQUAL(container.getLoadedIdentities().size(), 2);
   BOOST_CHECK(container.find(id1) != container.end());
   BOOST_CHECK(container.find(id2) != container.end());
 
+  // get identities
+  BOOST_REQUIRE_NO_THROW(container.get(id1));
+  BOOST_REQUIRE_NO_THROW(container.get(id2));
+  BOOST_CHECK_THROW(container.get(Name("/non-existing")), Pib::Error);
+
+  // check identity
+  Identity identity1 = container.get(id1);
+  Identity identity2 = container.get(id2);
+  BOOST_CHECK_EQUAL(identity1.getName(), id1);
+  BOOST_CHECK_EQUAL(identity2.getName(), id2);
+
+  // create another container from the same PibImpl
+  // cache should be empty
+  IdentityContainer container2(pibImpl);
+  BOOST_CHECK_EQUAL(container2.size(), 2);
+  BOOST_CHECK_EQUAL(container2.getLoadedIdentities().size(), 0);
+
+  // get key, cache should be filled
+  BOOST_REQUIRE_NO_THROW(container2.get(id1));
+  BOOST_CHECK_EQUAL(container2.size(), 2);
+  BOOST_CHECK_EQUAL(container2.getLoadedIdentities().size(), 1);
+
+  BOOST_REQUIRE_NO_THROW(container2.get(id2));
+  BOOST_CHECK_EQUAL(container2.size(), 2);
+  BOOST_CHECK_EQUAL(container2.getLoadedIdentities().size(), 2);
+
+  // remove a key
+  container2.remove(id1);
+  BOOST_CHECK_EQUAL(container2.size(), 1);
+  BOOST_CHECK_EQUAL(container2.getLoadedIdentities().size(), 1);
+  BOOST_CHECK(container2.find(id1) == container2.end());
+  BOOST_CHECK(container2.find(id2) != container2.end());
+
+  // remove another key
+  container2.remove(id2);
+  BOOST_CHECK_EQUAL(container2.size(), 0);
+  BOOST_CHECK_EQUAL(container2.getLoadedIdentities().size(), 0);
+  BOOST_CHECK(container2.find(id2) == container2.end());
+
+}
+
+BOOST_AUTO_TEST_CASE(Iterator)
+{
+  auto pibImpl = make_shared<PibMemory>();
+  IdentityContainer container(pibImpl);
+  container.add(id1);
+  container.add(id2);
+
   std::set<Name> idNames;
   idNames.insert(id1);
   idNames.insert(id2);
@@ -74,6 +140,10 @@
     count++;
   }
   BOOST_CHECK_EQUAL(count, 2);
+
+  BOOST_CHECK(IdentityContainer::const_iterator() == IdentityContainer::const_iterator());
+  BOOST_CHECK(IdentityContainer::const_iterator() == container.end());
+  BOOST_CHECK(container.end() == IdentityContainer::const_iterator());
 }
 
 BOOST_AUTO_TEST_SUITE_END() // TestIdentityContainer