In reply to Paul McKechnie:
I don’t think there’s much literature available on the topic. You could probably find some examples in the Verification Academy cookbooks, but even there it’ll probably limited to a device that takes input through one interface and outputs something through another interface (like the classical router example you find in most books).
There aren’t many resources available online, as companies aren’t eager to share code. The lack of free tools also doesn’t help, because it discourages hobby projects from popping up.