I ran a brief series on industrial data, interoperability, and the Purdue Model (see this one, for example, and others about that time). It’s about how data is becoming decoupled from the application. It’s not hierarchical, seeking out applications that need it.
This week I took a look at Opto 22’s latest innovation—use of RESTful APIs in an industrial controller. The next step seemed to be looking at MQTT. This is another IT-friendly technology that also serves as an open, standardized method of transporting data—and more.
Then I’ll follow up on a deeper discussion of OPC and where that may be fitting in within the new enterprise data architecture.
I’ll finish the brief series with an application of (perhaps) Big Data and IIoT. It’s not open standard, but shows where enterprises could be going.
MQTT and Sparkplug
Inductive Automation has been around for about 13 years, but it has shown rapid growth over the past 5. It is a cloud-based HMI/SCADA and IIoT platform. I finally made it to the user conference last September and was amazed at the turnout—and at the companies represented. Its product is targeted at the market dominated in the past by Wonderware, Rockwell Automation RS View, and GE Proficy (Intellution iFix in a former life). It’s a private company, but I’ve been trying to assemble some competitive market share guesses. My guess is that Inductive ranks very well with the old guard. Part of the reason is its business model that seems friendly to users.
Just as Opto 22 was an early strong supporter of OPC (and still supports it), so also is Inductive Automation a strong OPC shop. However, just as Opto 22 sees opportunities for better cloud and IT interoperability with REST, Inductive Automation has seen the same with MQTT. In fact, it just pulled off its own Webinar on the subject.
I put in a call and got into a conversation with Don Pearson and Travis Cox. Following is a synopsis of the conversation. It is also a preview of the ICC user conference in Folsom, CA Sept. 19-21. At the conference you can talk to both Arlen Nipper, president and CTO, Cirrus Link and co-developer of MQTT along with Tom Burke, president of the OPC Foundation.
Don and Travis explained that MQTT itself is a middleware “broker” technology. It describes a lightweight, publish/subscribe transport mechanism that is completely agnostic as to the message contained in the communication. So, you could send OPC UA information over MQTT or other types of data. The caveat, as always, is that the application on the receiving end must speak the same “language.”
They see apps talking directly to PLCs/PACs/controllers as going away. We are in the midst of a trend of decoupling data from the application or device.
MQTT is “stateful”, it can report the last state of the device. It rides on TCP/IP, uses TLS security, and it reports by exception.
Describing the message
MQTT is, in itself, agnostic as to the message itself. However, to be truly useful it needs a message specification. Enter Sparkplug. This technology describes the payload. So, it is needed on both sides of the communication. it doesn’t need to know the device itself, as it is all about information. it is a GitHub project and, as is MQTT, part of the eclipse foundation.
I have known Don and Travis for years. I have never heard them as passionate about technology as they were during our conversation.
If you are coming to Folsom, CA for the conference, you’ll hear more. I will be there and would love to have a breakfast or dinner with a group and dive into a deep discussion about all this. Let me know.