I’ve created this webpage as reference information for my presentation at the 2018 Maker Faire.
MQTT is the kind of technology that is difficult to capture the significance of and express in a succinct manner. A Google search says there are "approximately 894,000 results”, so where to start? Probably the best place is the MQTT Community site: http://mqtt.org/ The header at the top starts with the following:
"MQTT is a machine-to-machine (M2M)/"Internet of Things" connectivity protocol. It was designed as an extremely lightweight publish/subscribe messaging transport. It is useful for connections with remote locations where a small code footprint is required and/or network bandwidth is at a premium…”
This is a pretty good introduction but what does it really mean in practice?
To me it means that I can connect almost anything I make to anything else! It is like having a “Swiss Army Knife” for electronics or maybe a "secret sauce".
As an example, so far I have used MQTT for the following projects (goto projects page):
* Monitoring and controlling a 24+ year old home alarm system,
* Creating a bed-side alarm system monitor and lighting controller,
* Monitoring house temperature in the winter,
* Monitoring a new heat pump's electricity consumption during heating and cooling,
* Allowing access to the data and some control from the Internet.
When I say “almost anything I make” it is because the processor board that is used for the project must have a network connection and there must be a server. In the home automation scenario this likely won’t be a problem. There are many inexpensive and readily available controller boards based on the ESP8266 and ESP32 modules and the server can be a simple as a Raspberry Pi Zero W plugged into a USB power supply.
For a mobile system this might not be so practical but there are definitely ways to go about it.
Note: The diagram on the projects page is from http://www.steves-internet-guide.com which seems to be unavailable now.