public function start(
        $host,
        $port,
        $nonce,
        $resource = '/',
        array $protocols = array()
    ) {
        $version = Net_Notifier_WebSocket_Handshake::VERSION;

        $request
            = "GET " . $resource . " HTTP/1.1\r\n"
            . "Host: " . $host . "\r\n"
            . "Connection: Upgrade\r\n"
            . "Upgrade: websocket\r\n"
            . "Sec-WebSocket-Key: " . $nonce . "\r\n"
            . "Sec-WebSocket-Version: " . $version . "\r\n";

        if (count($protocols) > 0) {
            $protocols = implode(',', $protocols);
            $request .= "Sec-WebSocket-Protocol: " . $protocols . "\r\n";
        }

        $request .= "\r\n";

        return $request;
    }