What is a PLC?

To address this issue, solutions such as MQTT, in conjunction with the Specification, employ a publish-subscribe protocol to streamline communications from the edge of the network. While modern PLCs employ modern communication protocols, legacy PLCs that are still at the edge of the network require additional hardware to deliver the same functionality. Edge gateways, such as Ignition Edge IIoT along with an MQTT broker, pull data from legacy PLCs using poll-response and then transmit the data using a publish-subscribe protocol.

This IIoT architecture allows industrial organizations to build IIoT solutions on top of brownfield systems, improving bandwidth usage and making data from edge-of-network PLCs widely available throughout the organization.

The Future of PLCs

The industry continues to see new products entering the market ranging from devices like Programmable Automation Controllers (PACs), which combine the functionality of PLCs with higher-level PC functionality, all the way to industrial embedded hardware.

Even with these new products, PLCs remain popular because of their simplicity, affordability, and usefulness. And software like lgnition will enable organizations to maximize their usefulness for many years to come.