Edge of Network Gateway: The Missing IIoT Link

The Industrial Internet of Things (IIoT) is here and it's changing the way manufacturers think about business. These days, everyone wants to be connected, synced up, wireless, and remoted in. You name it, we want to be connected to it. Within the manufacturing industry there is great need and desire for increased connectivity and access to valuable data from our factory machines.

The Edge Gateway

How can your bottom line benefit from the Industrial Internet of Things today and in the future? Enter the Edge Gateway. The edge gateway unlocks valuable data created by existing operational technology, enabling your business to monetize it further with the power of information technology. In the manufacturing sphere, edge gateway devices translate existing data used by control applications into an IIoT-friendly format, sending that data to the Internet for use by IIoT applications.

For successful deployment, an edge gateway device must fulfill key requirements. It must communicate with a wide range of existing equipment and support emerging IIoT protocols such as MQTT. It must be efficient, reliable, and scalable. It must be easy to configure and put into service. Above all, it must be secure.

Maple Systems HMI—Your Edge of Network Gateway

A Human Machine Interface (HMI) is the perfect device for this role. The HMI, the operator's window into the machine in the physical world, can easily be extended to play the same role in the virtual world. The HMI is the place where data is aggregated, filtered, and presented to the operator in an intuitive and digestible way. This same data can easily be presented to users connecting to the HMI through the IIoT.

Works Well with Other Products and Systems

A primary requirement of the IIoT is the ability to work easily and flawlessly with other products and systems. The dizzying array of communication protocols used in manufacturing today could present a significant problem here. Fortunately, Maple Systems HMIs possess extensive libraries of industrial protocol drivers operating on different network architectures. Working seamlessly with other products and systems, Maple HMI's have the ability to unlock valuable data from existing machinery regardless of the protocol used. For example, Maple Systems HMI5097DXL has three serial ports and a CANbus port which can operate simultaneously utilizing over 200 different protocols. In addition, two separate Ethernet ports allow dedication of one port for real-time industrial control network demands while the other is reserved for external network connections and IIoT functionality. Distinctly separate Ethernet ports offer added security, since a direct network path does not exist to the machinery itself.

MQTT Structure

To fully realize benefits of the IIoT, data transmitted by the edge gateway-enabled HMI must be presented to upstream IT applications in a way that is flexible, modular, and efficient. The MQTT feature available on all Maple Systems HMIs exemplifies the power of this protocol. MQTT is organized into topics which can contain single data points or a group of related data. The HMI can be configured to transmit data from a specific topic whenever a change occurs, or on a periodic basis, lowering the bandwidth required for connection.

MQTT Advantages

A fundamental advantage of MQTT is that data is sent to a central "broker" instead of being directly transmitted to multiple clients such as remote interfaces or management software. The MQTT broker is responsible for maintaining client connections and sending/receiving messages. Client devices, edge gateways, and IT applications (or publishers/subscribers in MQTT language), are freed up to focus on producing and consuming data. This division of labor greatly enhances scalability. As overall system sizes grow, the CPU resources and bandwidth requirements of the edge gateway remain static. In addition, MQTT is a lightweight protocol. A popular broker implementation consumes only around 3MB of RAM with 1000 connected clients1. This small footprint means the HMI can be configured as both an edge gateway and an MQTT broker, reducing the need for additional hardware.

Data Utilization

Once an edge gateway produces data as an MQTT publisher, applications engineers enjoy great flexibility in utilizing that data. Topic names are assigned to the variables or tags they wish to publish to the broker. Topics are the titles, or addresses, used to organize data in MQTT protocol. MQTT allows topics to be broken down in intuitive ways. A single data point can be assigned to multiple topics and one topic can contain more than one data point. An application can subscribe to all topics on a single HMI, creating an application monitoring one specific machine. Or, if a parameter, say temperature, exists on many machines, the programmer can use a topic "wild card" enabling them to instantly subscribe to the same parameter across all machines. This enables efficient and easy detection of abnormal conditions across an entire installed base of machines.

Easy Implementation

For the controls engineer looking to incorporate an edge gateway into their system the HMI configuration process could not be easier: simply create an authenticated broker connection then select the tags you wish to publish. Point and click to organize tags into topics for your specific application, download the project to the HMI and you're up and running.

Increased Communication

MQTT is one of many internet-enabled applications available on edge gateway devices such as Maple HMIs, offering increased communication and data collection. For example, HMIs can send emails containing data log and alarm conditions. Remote access applications allow remote users to monitor and control machines through secure VPN connections and enables remote download of project updates. Database integration allows machines to log data directly to database servers over a LAN. Custom server/client applications enable smart device integration (Android/Apple tablets) for machine monitoring and control, moving the touchscreen out of the panel and into the operator's hands. Compared to machine replacement, edge gateway-enabled HMIs are an inexpensive option for upgrading existing machines or adding to new machine builds.

Safety Comes First

With so many features and access options, edge gateway safety and security are of utmost concern. This is why the Maple Systems HMIs can restrict access to data streams to authorized personnel and devices. There will always be a need for on-site trained control personnel ready to react to unsafe conditions. For critical systems that require onsite personnel for safety, the added protection of a one way, read-only connection allows offsite monitoring without control. This enables companies to meet their IIoT needs without sacrificing safety and security. The HMI edge gateway maintains the vital role of local machine control while opening up new possibilities in the IIoT today, tomorrow, and beyond.

"Mosquitto Overview." Projects.eclipse.org. Eclipse, 2013. Web. 29 Mar. 2016.
Facebook Messenger. (2016, March 20). In Wikipedia, The Free Encyclopedia. Web. March 22, 2016.