public function start()
  {
    $rememberMe = Remember::$rememberMe;
    $loginResult = $rememberMe->login();

    if ($loginResult->isSuccess()) {
      $_SESSION['_uas'] = $loginResult->getCredential();
      $_SESSION['remembered_by_cookie'] = true;
      return;
    }

    if ($loginResult->hasPossibleManipulation()) {
      exit();
    }

    if ($loginResult->isExpired() && !empty($_SESSION['_uas']) && !empty($_SESSION['remembered_by_cookie'])) {
      $rememberMe->clearCookie();
      unset($_SESSION['_uas']);
      unset($_SESSION['remembered_by_cookie']);
      exit();
    }
    if ($loginResult->isExpired() && !empty($_SESSION['_uas'])) {
      sleep(5);
    }
  }