protected function startCloseClient(
        Net_Notifier_WebSocket_Connection $client,
        $code = Net_Notifier_WebSocket_Connection::CLOSE_NORMAL,
        $reason = ''
    ) {
        $this->log(
            sprintf(
                'disconnecting client from %s for reason "%s" ... ',
                $client->getIPAddress(),
                $reason
            ),
            Net_Notifier_Logger::VERBOSITY_CLIENT
        );

        $client->startClose($code, $reason);

        $this->log(
            'done' . PHP_EOL,
            Net_Notifier_Logger::VERBOSITY_CLIENT,
            false
        );
    }