private static void inputCheck(int port, int windowSizeN, int timeout) {
		if (port > 65535 || port < 1024) {
			System.err.println("Port number must be in between 1024 and 65535");
			System.exit(1);
		}
		if (windowSizeN < 0) {
			System.err.println("Window size must be larger than 0");
			System.exit(1);
		}
	}