Overview

MQTT (Message Queueing Telemetry Transport) is a publisher/subscriber-based communication protocol, which enables message-based transfer between applications. A central component in this type of transmission is the so-called message broker, which is therefore a message-oriented middleware.

The message broker has the task of distributing messages between the individual applications, or the sender and receiver of a message. It decouples the sender and receiver, so that it is not necessary for the sender and receiver to know their respective address information. During sending and receiving all communication devices contact the message broker, which handles the distribution of the messages.

When a client connects to the message broker, security mechanisms such as TLS (Transport Layer Security) or even user name/password authentication can be used to encrypt the communication connection and realize authentication between client and message broker.