Anyway, even some of your supermarket systems speak LON or other protocols so you are working with things already. Here's the thing about that-- many OEMs utilize protocols, but few train people about them. They are strictly interested in their narrow application, even they at times don't realize how to do things. It shows in their product anytime you want to use it with other products.
If you are interested, start reading. They are many ways to get information. For instance, at the Loytec site I'd read their application notes. I'd buy the LON book(s) and understand what the ideal standards are and then you can realize what you are getting.