As they say these days, the Internet of things (IoT) is bringing up a third industrial revolution. Devices will be talking to each other more and more to share information, real time, and the need for a low power, secure protocol to connect those devices together is greater than ever.
What is MQTT? It is an OASIS-approved standard, machine-to-machine super lightweight transport protocol for publishing and subscribing activities.
MQTT client are always connected to what is called an MQTT broker, never to each other.
The MQTT protocol itself is based on top of TCP/IP, and both the MQTT client and the MQTT broker require a TCP/IP stack.
MQTT has been designed specifically for IoT and is well suited for a wide range of scenarios such as: