MQTT Brokers

The Message Queuing Telemetry Transport (MQTT) is a lightweight messaging protocol ideal for devices with limited resources and unreliable networks. An MQTT broker is a server that handles the distribution of messages between clients.

MQTT is a publish/subscribe messaging protocol that allows clients to communicate with one another through a broker. This mechanism decouples the sender and receiver, making it efficient for real-time communication.

MQTT brokers manage message routing between clients. Clients can publish messages to a topic or subscribe to receive messages from a topic.

        graph TD;
            A[Client A] -->|Publish| B[MQTT Broker];
            B -->|Distributes| C[Client B];
            B -->|Distributes| D[Client C];
        

4.1 Installing Mosquitto

Mosquitto is a popular open-source MQTT broker. Here’s how to install it:

        sudo apt update
        sudo apt install mosquitto mosquitto-clients
        

4.2 Configuring Mosquitto

Edit the configuration file located at /etc/mosquitto/mosquitto.conf to set parameters like listener ports and authentication.

        listener 1883
        allow_anonymous true
        

4.3 Starting the Broker

Start the Mosquitto service:

        sudo systemctl start mosquitto
        sudo systemctl enable mosquitto
        

• Use secure connections (TLS) to protect data.
• Implement authentication and authorization for clients.
• Monitor broker performance regularly.
• Use retained messages judiciously.
• Limit the number of connections to prevent overload.