@Michael_K , If we go from the front to the back this is what is needed: 1 Node: For example a door bell. This node sends information to a gateway. 2 The gateway takes the message from the node and sends this to a controller. For instance Openhab or Domotics. This can be done in several ways. MqTT being one. 3 Controller: takes the information and displays it to you. So in my case, I hardcode Node ID and CHILD ID (the complete door bell is a NODE whereas CHILD IDs may be the button pressed and maybe temperature reading at the same time). This sends to Gate way that takes the information and creates a MqTT message. What this message is, please read the instructions on this site.