MQTT: Its Implementations for Industrial cloud Applications

Eyeglasses reflecting computer code on a monitor, ideal for technology and programming themes.
Technical Brief

What is MQTT?

MQTT (Message Queuing Telemetry Transport) is a lightweight messaging protocol designed for efficient communication between devices, particularly in environments with low bandwidth, high latency, or unreliable networks. It operates on a publish-subscribe model, making it ideal for Industrial Internet of Things (IIoT) applications, where real-time data exchange is critical.

Originally developed by IBM and later standardized by OASIS (Open Applications Group Inc.), MQTT is widely used in industrial automation, remote monitoring, and control systems due to its low overhead, scalability, and support for constrained devices.

Understanding MQTT Components: Broker, Publisher, and Subscriber

MQTT Broker

The MQTT broker acts as the central hub for message exchange, managing all communications between clients. It receives messages from publishers and distributes them to the appropriate subscribers based on topics. The broker ensures reliable delivery and can handle multiple clients simultaneously.

Publisher

A publisher is any device or application that sends messages to the broker. Publishers do not send messages directly to specific clients but instead publish data to a topic. Any subscriber interested in that topic will receive the message.

Subscriber

Subscribers are devices or applications that express interest in receiving messages from specific topics. The broker ensures that whenever a message is published on a subscribed topic, the subscriber receives it in real time.

Key Features of MQTT for Industrial Applications

  • Lightweight Protocol – Minimal packet size ensures efficient communication over constrained networks.
  • Quality of Service (QoS) Levels – Three QoS levels (0, 1, 2) allow flexibility in message delivery reliability.
  • Retained Messages – Ensures that new subscribers receive the last known message state.
  • Last Will and Testament (LWT) – Notifies subscribers when a client unexpectedly disconnects.
  • Security – Can integrate with TLS/SSL encryption and authentication mechanisms for secure data exchange.

Types of MQTT Implementations for Industrial Applications

MQTT can be implemented in various ways to suit industrial automation and IIoT applications. Below are some of the most common implementations:

1. Standard MQTT Broker-Client Implementation

  • Uses a central MQTT broker to manage message exchange between clients.
  • Suitable for industrial monitoring, predictive maintenance, and SCADA systems.
  • Examples: Eclipse Mosquitto, HiveMQ, EMQX.

2. MQTT-SN (MQTT for Sensor Networks)

  • A variation of MQTT designed for low-power, wireless sensor networks.
  • Uses UDP instead of TCP, reducing power consumption.
  • Ideal for battery-powered industrial IoT devices.

3. MQTT with Edge Computing

  • Implements MQTT at the edge of the network to reduce latency and processing loads on cloud servers.
  • Used in industrial gateways, local controllers, and edge servers.
  • Helps in real-time processing and decision-making before sending data to the cloud.

4. MQTT Over WebSockets

  • Enables MQTT communication over web applications and browser-based dashboards.
  • Useful for remote monitoring and control systems in industrial automation.
  • Common in cloud-based SCADA solutions and IIoT dashboards.

5. Secure MQTT (MQTTS)

  • Implements TLS/SSL encryption to protect data integrity and confidentiality.
  • Often used in critical industrial applications where data security is a priority.
  • Can be integrated with X.509 certificates and token-based authentication.

6. Hybrid MQTT Implementations (Bridging & Multi-Broker Systems)

  • Combines multiple MQTT brokers to enhance scalability and redundancy.
  • Used in distributed industrial networks, factories, and multi-site operations.
  • Supports load balancing and failover mechanisms.

7. Sparkplug MQTT

  • An extension of MQTT specifically designed for industrial automation and IIoT.
  • Standardizes payload formats to ensure interoperability between industrial devices.
  • Enables real-time data exchange between SCADA, PLCs, and IIoT platforms.
  • Commonly used in manufacturing, energy management, and remote monitoring.

Types of MQTT Brokers

MQTT brokers act as intermediaries between publishers and subscribers, ensuring reliable message delivery. Different types of MQTT brokers cater to various industrial, enterprise, and cloud-based applications. Here are some of the most widely used MQTT brokers:

1. Open-Source MQTT Brokers

  • Eclipse Mosquitto – Lightweight and widely used, suitable for embedded systems and small-scale applications.
  • EMQX – High-performance, scalable, and supports clustering for large-scale industrial and enterprise deployments.
  • RabbitMQ with MQTT Plugin – An advanced message broker supporting multiple protocols, including MQTT, AMQP, and STOMP.
  • VerneMQ – A scalable, distributed MQTT broker designed for high availability and IoT applications.
  • NanoMQ – A lightweight MQTT broker optimized for edge computing and embedded systems.

2. Enterprise-Grade MQTT Brokers

  • HiveMQ – A high-performance enterprise broker supporting large-scale IoT and IIoT applications with cloud integration and security features.
  • AWS IoT Core – A managed MQTT broker offered by Amazon for IoT and cloud-based applications.
  • Azure IoT Hub – Microsoft’s cloud-based MQTT broker designed for IoT device communication.
  • Google Cloud IoT Core – Supports MQTT for IoT devices to integrate with Google’s cloud ecosystem.

3. Cloud-Based MQTT Brokers

  • IBM Watson IoT Platform – Provides MQTT messaging services for AI-driven IoT applications.
  • EMQX Cloud – A cloud-hosted version of EMQX, offering scalability and reliability.
  • Adafruit IO – A cloud-based MQTT broker designed for DIY and hobbyist IoT projects.
  • ThingsBoard – An open-source IoT platform that includes MQTT broker functionality.

4. Industrial and Specialized MQTT Brokers

  • Ignition MQTT Distributor (Cirrus Link) – An MQTT broker designed for industrial automation and SCADA systems using Sparkplug MQTT.
  • Sparkplug MQTT Brokers – Brokers supporting the Sparkplug B specification for IIoT and industrial automation.
  • Prosys OPC UA MQTT Broker – Bridges OPC UA and MQTT for industrial automation and process control applications.

Choosing the Right MQTT Broker

The selection of an MQTT broker depends on factors such as scalability, security, reliability, and integration needs. For industrial applications, enterprise-grade brokers like HiveMQ, EMQX, or Ignition MQTT Distributor are preferred, whereas cloud-based brokers are ideal for remote IoT deployments.

Conclusion

MQTT has become a cornerstone technology in industrial automation and IIoT, enabling efficient, scalable, and secure machine-to-machine communication. Various MQTT implementations and brokers cater to specific industrial needs, from low-power sensor networks to secure cloud integration. By selecting the right MQTT architecture, industries can enhance operational efficiency, reduce downtime, and improve data-driven decision-making.

Related Posts

Scroll to Top