/** Constructor */
    private MulticastChannel() {

        /** configuration via properties file, terminate if not found! */
        String address = constants.get(ZephyrOpen.address);
        String port = constants.get(ZephyrOpen.port);

        if (address == null) {
            constants.error("serverAddress not found in properties file, terminate!", this);
            constants.shutdown();
        }

        if (port == null) {
            constants.error("serverPort not found in properties file, terminate!", this);
            constants.shutdown();
        }

        try {

            groupPort = Integer.parseInt(port);

            /** get group ip */
            groupAddress = InetAddress.getByName(address);

            /** construct the server socket */
            serverSocket = new MulticastSocket(groupPort);

            /** join this group */
            serverSocket.joinGroup(groupAddress);

            /** find our ip */
            local = constants.get(ZephyrOpen.localAddress);

        } catch (Exception e) {
            constants.shutdown(e);
        }

        /** start thread, block wait on input from socket */
        server = new Thread(this);
        server.setDaemon(true);
        server.start();