public static function generateToken( $vary )
     {
         mt_srand( base_convert( substr( md5( $vary ), 0, 6 ), 36, 10 ) * microtime( true ) );
         $a = base_convert( mt_rand(), 10, 36 );
         $b = base_convert( mt_rand(), 10, 36 );
         $token = substr( $b . $a, 1, 8 );
         $tokenHash = sha1( $token );

         return $tokenHash;
     }