Deployer\Server\Remote\PhpSecLib::connect PHP Method

    public function connect()
    {
        $serverConfig = $this->getConfiguration();
        $this->sftp = new SFTP($serverConfig->getHost(), $serverConfig->getPort(), 3600);
        switch ($serverConfig->getAuthenticationMethod()) {
            case Configuration::AUTH_BY_PASSWORD:
                $result = $this->sftp->login($serverConfig->getUser(), $serverConfig->getPassword());
                break;
            case Configuration::AUTH_BY_IDENTITY_FILE:
                $key = new RSA();
                $key->setPassword($serverConfig->getPassPhrase());
                $key->loadKey(file_get_contents($serverConfig->getPrivateKey()));
                $result = $this->sftp->login($serverConfig->getUser(), $key);
                break;
            case Configuration::AUTH_BY_PEM_FILE:
                $key = new RSA();
                $key->loadKey(file_get_contents($serverConfig->getPemFile()));
                $result = $this->sftp->login($serverConfig->getUser(), $key);
                break;
            case Configuration::AUTH_BY_AGENT:
                $key = new Agent();
                $key->startSSHForwarding(null);
                $result = $this->sftp->login($serverConfig->getUser(), $key);
                break;
            case Configuration::AUTH_BY_IDENTITY_FILE_AND_PASSWORD:
                $key = new RSA();
                $key->setPassword($serverConfig->getPassPhrase());
                $key->loadKey(file_get_contents($serverConfig->getPrivateKey()));
                $result = $this->sftp->login($serverConfig->getUser(), $key, $serverConfig->getPassword());
                break;
            default:
                throw new RuntimeException('You need to specify authentication method.');
        }
        if (!$result) {
            throw new RuntimeException('Unable to login with the provided credentials.');
        }
    }