OPC Experts Interview: What is OPC?

OPC Experts Interview: What is OPC?
OPC Experts Interview: What is OPC?

The OPC Experts Interview is a series taking a deep dive into open platform communications, OPC/OPC UA and related technology. This interview is with Stefan Hoppe, President and Executive Director of the OPC Foundation.

What is OPC, who is it for, and why should one care? 
Hoppe: Well, today the acronym OPC stands for open platform communications. OPC is an interoperability standard which allows a secure and reliable data exchange in the area of industrial automation and other industries. OPC is a completely independent platform that allows data to move seamlessly between multiple devices from different vendors. It scales from sensor to cloud. Users care about this technology for many reasons, including a key role that OPC plays in Industrie 4.0 and IIoT – making data available across every automation sector.

What is the OPC Foundation and its role?
Hoppe: The OPC Foundation develops and maintains the entire set of OPC specifications, but we also provide mechanisms to ensure the quality of these standards through associations with compliance labs and various test tools. Since the specification provides the mechanisms describing “how” to move data, we also collaborate with many other associations, defining “what” to exchange.

Here at the OPC Foundation, we feel a little bit like the United Nations of automation, especially since our goal is to remain completely independent – One big vendor cannot define the direction of the Foundation nor what it is to do – It's democratic. Each year, half of the board members are democratically elected, so no one can buy influence with money. We are completely independent in taking care of this standard.

How can you, as an organization, accomplish such a huge goal?
Hoppe: Well, first of all, you need to define a goal upon which everybody in the world can easily agree. Then, of course, you need a critical mass of companies to support this. The easy vision of the OPC Foundation is to provide a standard where users and vendors come together to define a mechanism to transfer data from multiple vendors and multi platforms in a secure and reliable way. Since this applies to the area of industrial automation, it has to scale in different areas. That's an easy-to-understand goal because everybody comprehends the benefits.

Secondly, it’s important to keep the organization independent so that nobody believes it is driven by a specific company. Acting independently is the key for us to refer to ourselves as the United Nations of automation. We feel like being the neutral ground upon which everyone can easily meet.
    OPC-Logo-Color_250px_72ppi_RGB.jpg   The OPC Experts Interview is a series of discussions taking a deep dive into open platform communications and related technology. International experts discuss OPC and OPC UA, protocol binding, security, the new Field Level Communications group, projects and experiences, and more. Automation.com is the exclusive publisher of these interviews, which are conducted by OPC Foundation personnel. Check back frequently to read the latest interviews.

Can you give us a little insight into the history of the OPC standard, why and how it came to market, how old or how young it is, and its major milestones?
Hoppe: I don't want to spend a lot of time on its history, but I can tell you a secret – OPC, in its early days, was called OLE for Process Control.

In 1990, SCADA companies had to write a lot of proprietary drivers to connect to PLC controllers. The idea was born to take the Microsoft COM/DCOM printer driver concept, to have standardized access to the upper (north-side) port, and establish a proprietary last-mile to all the different PLC controllers. That was the birth of what we now know as OPC Classic. It provided live data, alarms, and historical data. It was massively successful. We had broad adoption inside the industry, but, of course, we recognized later, that we needed to be platform independent; we needed to integrate security; we needed a service-oriented architecture mechanism inside. That's why, from 2003 through 2006, we started separating services from data. This was the birth of OPC UA.
UA stands for Unified Architecture. We unified everything together into one architecture and then we validated everything; we made prototypes; and then, at last, in 2008, OPC UA was released.

Since then, we’ve had products on the market with no compatibility break. Modern cloud applications connect to OPC data, even to devices from 2007. Today, OPC UA is a complete technology, independent from operating systems, independent from vendors, and it has security built in, by design. That's really important to understand.

Who are your members and what countries are they from?
Hoppe: All kinds of companies, in all kind of areas throughout the world. I believe that OPC is the largest ecosystem for industrial interoperability, worldwide. Our members include very small companies, the big giants of the market, providers of technology, and, of course, end-users.

The status today is that OPC Foundation has more than 750 members in all regions in the world. Analysts say that we have more than fifty million applications worldwide – It's a huge ecosystem. Statistics indicate that 50% of our members are headquartered in Europe with around 25% in the US and 25% in Asia, and I see that Europe and Asia are growing very quickly.

What would you say is the major driver for this difference in acceptance across the global markets?
Hoppe: Well, in Europe, there is the initiative called Industrie 4.0, which is named differently in a couple of countries. It's all about how to make workflows more efficient; how to get data.

The scope of Industrie 4.0 is huge; starting with how to design a product, consideration for its entire life cycle, including the end of a product. Whereas, OPC UA addresses mainly, but not exclusively, how to connect during the production phases of the live data. The idea is easy to understand; you need something like a USB connector for machines, which allows you to reduce engineering costs, and provides standardize data. Think of the benefit of having OPC UA in a device (or a machine) and then being able to connect this machine within only 10 minutes to SAP MES, or Microsoft Azure, to name just two of them. It is easy to understand.

That's exactly why end-users like Volkswagen, Samsung, Foxconn, Miele, and others have joined the Foundation; because they understand these big benefits. That's a key value.

Tell us a little bit about the technology behind the OPC standard.
Hoppe: That's not easy to explain – and we will definitely share separate interviews on that topic – but let me address it briefly in three blocks. Before I do, however, we have to understand that OPC UA is not another protocol. We have so many, we don't need another one. In today's world, I believe that protocols are not really a high-value item. What is valuable is the secure exchange of information and to know the meaning of that information.

So, first of all, with OPC UA, you are describing and modeling data interfaces that your machine or device should expose via live data, historical data, alarms, and so on. Then, secondly, deeper within the OPC UA framework, we see different communication mechanisms built in already by design. Client/ server is one, publisher/ subscriber is another. These are still independent from the real protocol beneath.

The third block is the real protocol binding layer. Here we are using OPC over TCP, HTTPS, UDP, MQTT or whatever other protocols may come in the future. Here you really see the benefits, because you are defining data and information. Keep in mind, these models will persist for many years to come, even when OPC is extending the protocol mechanisms to support more endpoints for new and existing protocols, for even more use cases.

Although designing data models is of key importance, security must be built in by design; and not just for the transport layer. Security also applies to authentication, those who are allowed to access particular kinds of data; how I manage a big factory; how I perform discovery and certificate management, automatically, and so on. 
So, you see that OPC UA is much more than a protocol. That's why we are not comparing OPC UA to protocols by asking, “should I use OPC UA or MQTT?” No! More correctly, we are using MQTT inside the OPC UA architecture! This allows us to move standardized data up into cloud scenarios.

As a standard, how do you make sure providers of the OPC technology stick to the rules? Do you certify their products?

Hoppe: In the beginning, the OPC Foundation started as a community of vendors creating their own tools, for example, the CTT tool [Compliance Test Tool], which OPC corporate members can get at no cost. But you don't even have to be a member, paying member fees; you can just buy that tool.

I believe that, today, the CTT performs 2000 test cases which you can run against your product to prepare yourself so you can deliver a higher quality product. Alternatively, we have labs in different regions throughout the world to test your product. Manufacturers can even participate while sitting next to the test lab engineer, if they wish. We perform multiple tests on many different products; things like stability tests over 36 hours, looking for memory consumption, and so much more.

What about collaboration with other international organizations; why would other organizations be interested in working with the OPC Foundation?

Hoppe: Well, the other associations have the domain specific knowledge – they know about a robot, an injection molding machine, or a coffee machine – this is not the specific knowledge of the OPC Foundation. We are able to move data in a secure way; and scale it from sensor to cloud. So, collaborating with these associations is a perfect win-win situation. I’ll say it in easier words: The OPC foundation provides the technology for “how” to exchange data and information in a secure way, and our partners define the “what” – they define the vocabulary of data and interfaces, ensuring, for example, that all robots have the same parameters, the same interfaces, and provide the same meaning.

You mentioned one or two, but what other companion specifications exist today?

Hoppe: Today, we have about 52 active collaborations – all of them publicly documented – they are on the Foundation’s website where you can download a .pdf document wherein you can see who is responsible for running each group. If you wish, you can simply contact the chairperson to become an active member or, perhaps, just a listening member, reviewing documents so you can inform yourself as to what's going on.
Of course, I can't list them all here but just to name a few: In the United States there is an initiative sponsored by the MDIS network [MCS-DCS Interface Standardization] focused on standardizing communications between subsea and topside equipment among offshore oil and gas systems.

In Europe the VDMA [The Mechanical Engineering Industry Association] is supporting more than 22 companion specifications. They are Europe’s largest association in the disciplines of the mechanical engineering industry; this covers robotics, injection molding machines, and more.

We are also involved in areas like the pharmaceutical industry, participating in the OPEN-SCS [Serialization Communication Standard] initiatives; the tobacco industry; the energy industry. But then, there are also generic topics, which are independent from a market; topics like Asset Management. Additionally, we are supporting commercial kitchen equipment initiatives – there, too, is an industry where standardized data models are needed.

Can members or others initiate collaborations?

Hoppe: Starting a new initiative depends a little bit, since everybody in the world can write an OPC UA companion specification. You start by going to the OPC website, downloading the publicly-available documents, and then you start filling them in.

For example, let’s say I want to model a coffee machine. Well, we have that standard already, but you can do it again, on your own, if you want. Then it's your own companion spec; your company driven companion spec.
The OPC Foundation tries, first, to do collaborations with other associations; then we need to draft a memorandum; then we extend a call for participation; then we provide all the compliance rules, etc… The idea, really, is to work with associations throughout the world, to have a broader acceptance and a broader adoption across global industries.

OPC Foundation introduced the Field Level Communications group. Can you tell us more about this major initiative?

Hoppe: Yes. It was very important to integrate this initiative under the roof of the OPC Foundation because it's extending the vision of OPC UA for the independent, secure movement of information from sensor to cloud. This addresses requirements of both factory automation and process automation. We explicitly include deterministic communications, which we are establishing in the future with TSN [Time Sensitive Networking], plus future integration of 5G networks, but also functional safety and motion.

Each of these three major functions – deterministic communication, functional safety, and motion – are options which users will be given the choice to enable. An example would include a case where an end-user may choose to enable deterministic communication between two controllers from different ecosystems.
I believe the functional safety specifications will be delivered sooner than the others since we started this working group earlier, as a joint cooperation with PNO, within the OPC Foundation. Both TSN and 5G will take more time because it's highly complex to handle all these topics – to configure and use a network of TSN enabled devices in a consistent way. This is not something that could be completed within a year, or something like that.

Is there anything else that is, or has been in the news that you would like to share with our readers?

Hoppe: I was at the EMO Trade Show in Hannover …it was so amazing that, within just one year, 70 companies from 10 countries around the world – not Europe only, it was the United States, China, Japan, Korea, Taiwan, they came together from everywhere; they agreed on vocabulary; they agreed on what data to exchanged; they called this initiative UMATI [Universal Machine Tool Interface].

At that trade show, 110 machines and 28 software packages from these 70 companies out of 10 countries, inter-connected and were showing their data in an exactly identical, semantic way. I saw big dashboards and could navigate into one hundred and ten machines. That was a huge success and I truly believe we will hear more from them in the future.

Well, looking now to the future, what I’d like readers to remember is that if we are writing companion specifications, with a lot of partners, for a lot of machines, in different markets throughout the world; if you envision these companion specification, like a book –each book describing a machine, the types of interfaces it has, the meaning of its data, the behavior of the machine, and then, as a result, you have a huge collection of books – the OPC Foundation then becomes the world library of descriptions of industrial devices and industrial things.

That's exactly what's happening right now, although there’s a lot of overlap. A robot may need an MES interface; a robot may need overall efficiency data; in the future, a robot might have a power management interface …and a whole lot more. These features may also turn out to be things that other machines might need; not only in factory automation, but also in the area of process automation.

Harmonizing all this data and all these interfaces is something that the OPC Foundation manages. As such, we started a new working group that has created an online platform – a library. It includes all of these companion specification groups, their information, and what they believe is critically important for others. You don't need to go into a store to buy a book since everything is available electronically these days.

Simply go to the OPC website and navigate throughout this online library to learn if a group has already worked on something in which you’re interested. Perhaps you can re-use parts of that existing product. Again, the OPC Foundation helps to harmonize these work-products to make results better. This is, for me, critically important, because I truly believe that, in the future, we will have automatic code generators, referencing sources within this online library. For example, I envision the time when the Foundation provides access to artificial intelligence systems so they know, exactly, the meaning of a particular, standardized data set.

Perhaps some readers wish to become a member of the OPC Foundation. What is the best way for them to do that?

Hoppe: Well, the landing page of the OPC Foundation is definitely a good starting point. It's opcfoundation.org. There, you’ll find all kinds of information; you can download brochures about OPC UA technology; you can find a link to all the YouTube videos; you’ll see an overview of all the international events. Perhaps there is one in your region, or even online. There's a lot of information.

You can find a section outlining member benefits, taking part, and getting early insights. Overall, I believe that having early insight is the biggest benefit to being a member, because once a specification is released everything is publicly available anyway.

We have public open source-code and all the released specifications are publicly available. Non-members can buy certification tools, but if you want to have insights on what's going on, and what's influencing your world within the next two or three years, then you should become a member.

For any further questions, please send an email to office@opcfoundation.org and let’s stay in touch.

Article adapted from an interview conducted by Peter Seeberg.

About The Author

Michael Clark as the Director of OPC Foundation North America and a spokesperson for the Foundation throughout the region. With over 30 years of experience, Clark is internationally recognized in the process automation sector for his expertise in Industrial Control System (ICS) fieldbus protocols and for his contributions to the Open Process Automation Standard (OPAS) since its inception.

Learn More

Did you enjoy this great article?

Check out our free e-newsletters to read more great articles..