simple AsyncApplLayer
    parameters:
		debug: bool, // debug switch
		headerLength: numeric const, // length of the application message header (in bits)
		iaitime: numeric, //generate msg period
		sourceAddress: numeric,
		destAddress: numeric,
		maxNumBurst:numeric,
		release_time:numeric,
		limit:numeric;
    gates:
		in: lowergateIn;
		out: lowergateOut;
endsimple