Why is Linux Trending?

Without a lot of fanfare, the use of Linux in automation has been gaining significant ground due to its openness and flexibility. Its common IT programming languages add to its appeal as IT and OT grow closer and new engineering teams emerge on the scene.

There have been a number of highly visible, fast-moving trends in industrial automation technology over the past few years. The most notable of these has been the Internet of Things and its related mobile and remote applications. Other high-profile trends include the rise of augmented and virtual reality and the proliferation of industrial cybersecurity companies.

Somewhat under the radar, another trend has been developing: The increasing use of Linux as a leading operating system (OS) for automation controllers.

A major factor behind industry’s interest in Linux has always been the technology’s openness. Industry’s desire to have its technologies be less proprietary and more open—thereby allowing companies to select and exchange their technologies more easily—is, of course, nothing new. The most aggressive industry push for open automation technologies can be seen in the activities of the Open Process Automation Forum.

But in years past, technologies powered by Linux have mostly been niche products offered to appeal to a small segment of the industrial market with the willingness and expertise to buck the more widely used systems. More recently, however, it’s become rare for me to attend meetings with technology suppliers who are not loudly touting their support for Linux with an array of products.

To find out what is driving this surge in Linux-powered products, I spoke with GE Automation & Controls, Opto 22, Wago and Wind River.

Behind the trend
The primary driver of the Linux trend is “the desire for flexibility to develop anything the engineer or developer can dream of in an industrially hardened, standards-compliant computing platform at a price point suitable for widespread deployments, and with headroom to expand and grow,” said Benson Hougland of Opto 22.

Adding to Hougland’s headroom comment, Charlie Norz, Wago product manager, said Linux OS’s future proof factor appeals to “a new generation of programmers who have been trained to develop Linux-based languages like C++ and Python.” He also pointed out that the amount of programs for Linux has “increased ten-fold and people are responding to that. No one wants to be restricted into one way of doing things, so having the flexibility to customize is increasingly attractive.”

Vibhoosh Gupta of GE Automation & Controls concurs with Norz’s viewpoint on the new generation of programmers, as well as Hougland’s points about Linux’s edge for innovation. Overall, he sees three key aspects behind the Linux trend across industry:

Millennials want to have the ability to optimize their processes using the latest programming languages, such as Python or C/C++ rather than being grounded to traditional IEC languages. The IEC1131 languages have their place, but optimization and analytic algorithms are usually better served by the languages like Python and Matlab.

Having the capability, at the edge, to run and write machine learning algorithms to optimize processes on a whole different level than has ever been done before is definitely driving the Linux trend.

Industries race to differentiate and innovate faster. OEMs want to differentiate their offerings and innovate at today’s pace. Remember that the mobile industry is just 15 to 20 years old, and we are already deploying 5G—that’s the kind of pace of innovation we would want on the industrial side as well. Consumer productivity has outpaced industrial productivity significantly in the past ten years.

With these drivers in mind, I wondered what it was that users liked about Linux beyond its flexibility.

“Linux has been around for a while, so it is robust, scalable and offers high levels of reliability proven through various use cases across multiple market segments,” noted Michel Genard, general manager of Wind River’s operating system business (Editor’s note: Intel sold Wind River to TPG private equity on April 3, 2018, while this article was being developed). “Additionally, Linux inherently offers reasonable licensing terms, a large community of developers and various avenues for support that promote confidence. Plus, companies with a track record in industrial automation are providing the services and support that make Linux commercially viable. This includes software update capabilities in development and post-deployment, continuous security monitoring and vulnerability protection, IP and export compliance artifacts, and an unparalleled range of high-quality board-support packages across a variety of architectures. This ensures that the total cost of ownership [for systems built on Linux] remains predictable.”

“With a Linux OS, users can run applications in parallel that provide specific value to their business needs,” said Norz. “These types of applications used to have to run in a PC that collected field data from a PLC. Now, it can all be run in one device—saving time and money as well as reducing data latency. Our Linux PLC users can use other applications like SQLite or MySQL to log and analyze data onboard the PLC. This also allows users to choose the security programs they feel comfortable with. It’s an intuitive, all-in-one solution.”

For more information about the use of Linux for real-time industrial applications, see this companion article.

Products and purchasers
Considering all the upsides to the use of Linux in industrial control systems, what kinds of automation products are available to OEMs and end users that leverage the OS?

Opto 22’s support for Linux can be found in its groov EPIC edge programmable industrial controller and groov Edge Appliance. Hougland said purchases of these devices come from a wide range of industries—from oil and gas, to water and wastewater, and OEM machinery.

“Each of these purchasers use the products in ways that make sense for their specific applications,” he said. “For example, end-user companies will likely use EPIC and the Edge Appliance with the installed suite of software, which provides control programming, connectivity and HMI. These end users will not necessarily take advantage of the system’s Linux operating system. But they know it’s there to expand upon if needed. And they recognize the lower total cost of ownership benefit that embedded Linux systems offer.”

For OEMs, however, it’s a different story. “OEMs and advanced system integrators recognize the power and openness an embedded, industrial Linux-based system can deliver in protecting their software intellectual property. They also like the ability to use standard development tools like C, C++, Python and Java for their control programs; and the ability to access computing and file systems through secure shell access,” Hougland said.

Norz noted that Wago offers Linux in its PFC series of controllers and in its 750 XTR controller series for extreme and hazardous location environments.

According to Gupta, GE Automation & Controls’ PACSystems Rx3i CPL400 uses “Type 1 hypervisor technology to run a real-time OS (such as VxWorks) running traditional control loops alongside our PACEdge technology operating on Linux.” GE’s PACsystems CPE400 controller uses the same technology as CPL400, but “runs our Field Agent technology on Linux to run Predix-based Edge applications and provide secure connectivity to the Predix Asset Performance Management applications,” he said.

“OEMs and system integrators are the ones who seem to be most excited about this [Linux] concept,” said Gupta, “as it allows them to securely and cooperatively run their differentiated content and analytics—their IP— closer to the asset.”

Genard said Wind River’s use of Linux extends across its Wind River Linux and Titanium Control products. “Wind River Linux is our embedded Linux offering that enables OEM customers to reduce development risk and time-to-market when building and deploying Linux-based devices. For end users and OEMs, Wind River Titanium Control is our on-premise cloud infrastructure platform for industrial IoT that uses open-source components, including Linux, which Wind River hardened for an industrial-grade environment. It delivers the uptime and performance needed for industrial applications and control services at any scale.”

Though Linux clearly has a strong appeal for OEMs, interest from end users is also strong, according to Genard. “OEMs tend to purchase Wind River Linux subscriptions because of the value that they provide in enabling faster time to market, stronger security and lower development risk resulting in a lower cost of total ownership,” he said. “When looking for open source software-based solutions, end-user companies prefer solutions built on Wind River Linux because of their confidence in the security, support and maintenance throughout the entire solution lifecycle.”

Interest in Linux is also widespread across the globe based on the interviews conducted for this article. “We see similar market strength for Linux in EMEA [Europe, Middle East and Africa], North America and Japan, and we’re growing business in APAC [Asia-Pacific], specifically China,” said Genard.

“We see high interest in Linux all around the world,” added Norz. “Probably because saving time, increasing efficiency and lowering the bottom line is a popular idea for any business anywhere.”

What does it mean for industry?
“This trend is just getting started,” said Hougland, “and it is largely fueled by incoming engineers and developers who are trained and qualified on these technologies and unwilling to settle for doing things the way they’ve always been done. These are the engineers and developers who will build our next-generation control systems.”

Norz sees it as “a sort of technological awakening. The industrial world is in the process of catching up to the rest of the technological world and implementation of this technology is accelerating across all industries. We’ve seen the early adopters, and now we’re at the brink of this becoming common practice. Education is what’s going to push us past the tipping point and further accelerate this phenomenon.”

The potential staying power of Linux in manufacturing and processing is underscored by industrial product lifecycle expectations, said Genard. “We see a renewed focus on the commercialization aspects of Linux—things like security, support and maintenance—throughout the lifecycle of a solution that has been built from the ground up for the industrial environment. This becomes particularly pronounced in the case of industrial companies where the product lifecycles are much longer than in the standard IT environment.”

Gupta said Linux’s openness, as it pertains to its ease of use, customizability and secure nature, make it “more appealing to many who tend to think of the resulting product as more of an appliance.” But he also cautioned against any expectation, at this point, that Linux will necessarily become the dominant OS of choice for industry. “We fully expect Windows to catch up. We see Windows IOT as another choice of OS, apart from Linux,” he said. “We chose Linux as our first OS for all the reasons I noted, but we are exploring other variants, including Windows.”

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