// Check AES Keys for unicity
        public void TestUniqueAESKeys()
        {
            int numKeys = 100;
            List <KeyParameter> keys = new List <KeyParameter>();

            for (int i = 0; i < numKeys; i++)
            {
                KeyParameter k = KeysHelper.generateAesKey();
                keys.Add(k);
                Assert.IsTrue(k.GetKey().GetLength(0) == 32);
            }
            Dictionary <String, KeyParameter> keysBytes = new Dictionary <String, KeyParameter>();

            keysBytes = keys.ToDictionary
                        (
                //Define key
                element => Convert.ToBase64String(element.GetKey()),
                //Define value
                element => element
                        );

            Assert.IsTrue(keysBytes.Count == numKeys);
        }