I am making a home automation project based on star topology. What I am trying to achieve is that one of the nodemcu/ESP8266 acts as a server which is accessible for the outside world and other nodemcu/ESP8266 acts as clients which are connected to relays or sensors.
Upon receiving the command from the server, the relays must be triggered accordingly and update the status back to the server. I read lots of tutorial via different methods. MQTT seems good but I don't want to use any third party broker like Adafruit. I want to host the web server either on my nodemcu or my web host. The sad part is I don't own a Raspberry Pi.
Can I use one of my ESP8266 devices as an MQTT broker, or is there a suitable alternative?