public function connectAndAuthenticate() {
		// 1. connect
		if (!$this->isConnected()) {
			$this->connect();
		}
		$this->hello();
		
		// 2. open tls connection if needed
		$securityMode = $this->config->getSecurityMode();
		if ($securityMode == SmtpConfig::SECURITY_MODE_TLS) {
			$this->startTls();
			$this->hello();
		}
		
		// 3. authenticat if needed
		if ($this->config->doAuthenticate()) {
			$this->authenticate();
		}
	}