It's just one of many ways to do this. Websockets, ZeroMQ, HTTP long-polling, or just a plain old TCP socket would have worked as well, just to name a few. I

It's just one of many ways to do this. Websockets, ZeroMQ, HTTP long-polling, or just a plain old TCP socket would have worked as well, just to name a few. I just went with MQTT because somebody had already implemented 95% of what I needed.