protected function createTwilioDriver()
    {
        $config = $this->app['config']->get('sms.twilio', []);

        return new TwilioSMS(
            new \Services_Twilio($config['account_sid'], $config['auth_token']),
            $config['auth_token'],
            $this->app['request']->url(),
            $config['verify']
        );
    }