Industrial Automation

MQTT: Transmit Data from OT to IT without Losing Data Integrity

Chang Yau Lua & Jonnel Galibo
MQTT’s decoupled communication model presents significant benefits for IT/OT convergence.

 

As IT and OT expand and evolve in different directions, each with its own goals and priorities—IT focuses on data and OT on processes—IT/OT convergence is the key to pushing organizations forward in the industrial world.

 

Although data is traditionally IT’s focus, data plays a big role in OT processes, too. While collecting data is one challenge, making it valuable is another.

 

How can you smoothly transmit data from OT to IT without overloading hardware or losing data integrity?

 

Throughout the years, MQTT has been the go-to for IT/OT communication, enabling efficient and reliable data exchange between systems and devices. Unlike traditional protocols, it’s known for being lightweight, efficient, and reliable. But before we dive into its benefits, let’s get to know MQTT’s history and how it works.

 

When Was MQTT Created?

In 1999, IBM created the MQTT protocol. It was originally called MQ Telemetry Transport, with “MQ” standing for IBM’s product series. The protocol was used for remote telemetry applications in the oil and gas industry, where low power and bandwidth are required.

 

As time went on, IBM made MQTT 3.1 available as an open protocol. Then, in 2014, it was standardized by OASIS.

 

In 2019, an upgraded version called MQTT 5 was released. Interestingly, MQTT is no longer just an acronym—it’s the name of the protocol itself.

 

How Does MQTT Work?

MQTT follows a publisher/subscriber model, which involves two key components:

 

  • MQTT Broker: The mediator for all client-to-client communication. When a device wants to share a message, it passes it to the broker, and the broker makes sure it gets to the right recipient.

  • MQTT Client: Can be a publisher, a subscriber, or both. A publisher is a machine that sends out messages, while a subscriber listens for specific messages it’s interested in.

Initially, the client creates a session with the broker. Once connected, clients can send messages if they have something to share, subscribe to topics they’re interested in, or do both at the same time.

 

When a message is sent, the broker receives it and acts like a filter, making sure it goes to the subscribers who are interested in that type of message.

 

In essence, MQTT simplifies communication between devices by using this publisher/subscriber setup. The broker manages the flow of messages between clients, ensuring that everyone gets the information they need.

 

MQTT Publisher/Subscriber Decoupling Features

Because the broker stands between the clients’ communication, it eliminates the direct connection between the machines, offering an uninterruptible communication for publishing and subscribing messages between clients.

 

This decoupling feature is categorized in multiple dimensions:

  • Space decoupling, where clients are unaware of each other (they only need to know the broker).

  • Time decoupling, where clients can publish and subscribe to the same topic at different times.

  • Sync decoupling, where clients can operate asynchronously without needing a response from each other.

Compared to traditional OPC/UA mechanisms, this decoupled communication model presents significant benefits for OT users.

 

Unlike OPC/UA, which requires direct point-to-point connections between devices and servers, MQTT’s decoupling allows for greater flexibility, scalability, and resilience.

 

OT systems seamlessly integrate with IT infrastructure without being tightly bound to specific protocols or hardware dependencies, facilitating interoperability and futureproof deployments.

 

Where Can MQTT Be Useful?

Implementing MQTT is particularly appropriate in scenarios where flexibility, scalability, and real-time data exchange are most important.

 

Energy Management Systems

In manufacturing facilities or commercial buildings, MQTT can integrate with energy management systems to monitor and control energy consumption in real-time. IT platforms can analyze this data to optimize energy usage patterns, while OT systems can dynamically adjust equipment settings for maximum efficiency.

 

Predictive Maintenance

By leveraging MQTT’s lightweight messaging, OT systems can transmit sensor data to analytics platforms for predictive maintenance. This reduces downtime and optimizes asset performance.

 

Healthcare Monitoring Systems

In healthcare facilities, MQTT can integrate medical devices, patient monitoring systems, and electronic health records (EHR) platforms. OT applications can transmit patient vitals and sensor data to IT systems for remote monitoring, alerts, and predictive analytics, enhancing patient care and operational efficiency.

 

Supply Chain and Inventory Management

MQTT facilitates communication between production systems, warehouse management system (WMS) platforms, and enterprise resource planning (ERP) platforms. OT systems provide real-time inventory updates, shipment tracking, and demand forecasting to IT systems to optimize inventory levels, order fulfillment, and supply chain visibility.

 

How Can Belden Help?

As Belden’s portfolio continues to evolve, our comprehensive, end-to-end networking solutions are tailored to you throughout your Industry 4.0 journey.

 

Our robust pre-ingestion solution operates seamlessly at the field level and supports multiple protocols. Leveraging our extensive range of I/O modules, we empower businesses to gather essential data efficiently and effectively.

 

In addition to our cutting-edge data collection capabilities, we recently launched OpEdge, our flagship edge computing device hardware. Designed for on-premises implementation, OpEdge facilitates streamlined data processing and analysis at the edge of the network, ensuring real-time insights and decision-making.

 

Complementing OpEdge is Belden Horizon Data Operations (BHDO), our innovative edge-deployed application. Together, these solutions enable your organization to harness the power of edge computing, driving operational efficiency and unlocking new possibilities in the digital age.

 

In terms of MQTT communication, OpEdge-8D and BHDO, along with an integrated MQTT Broker container, will be responsible for receiving and filtering the data sent by sensors and other machines. Afterwards, this data can be shared with the clients, depending on their subscribed topics.

 

Belden’s expanded networking and vendor-agnostic data solutions empower your business to embrace the transformative potential of Industry 4.0.

 

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