Industry 4.0 and IT/OT convergence: A brief, un-salesy, very un-annoying explanation

 Originally published on October 28, 2020 by Patrick Gebhardt
Last updated on January 23, 2024 • 11 minute read

The digitization or digitalization of established industrial processes can be called by numerous fancy names, the most common one being "Industry 4.0". This name is so appealing to many due to its idea of continuity. The first industrial revolution was mechanization by means of water and steam power. The second one was characterized by mass production using assembly lines and electrical energy. And the third one (digital revolution) was the use of electronics and IT to automate production. It is often true that the fancier the name, the more half-baked or too theoretical the idea is. This is really not the case with Industry 4.0. But if you want to get even basic information on this topic for the first time from the Internet, you have to dig deep into the dense buzzword jungle to find reliable details. Hence the idea for this article. My suggestion: You read this article, and I spare you buzzword terms like Fourth Industrial Revolution, IIoT, M2M, or whatever. Deal?

Automation and networked systems

Here's the problem with "traditional" industrial IT: it's really good at what it does, so why change?

In the workflows of every factory there exists a super relevant field next to traditional IT (more on this below) that is evident, due to digitization and digitalization to an ever-increasing degree, with the following concepts:

  • Automation: This is in contrast to a centralized, human control of machines. So far, regarding IT, information can be collected in different systems and evaluated by individuals, who then make adjustments. But this also means the almost unconditional requirement of a further, human evaluation instance.
  • Networked systems: These make it possible to exchange data and thus information between machines, and for the machines to efficiently react to each other. Even this kind of interconnection cannot be found in most processes of industrial IT so far.

In the future, machines will take care of themselves more autonomously and all machines (as well as many of the goods they produce) will be equipped with sensors. These sensors will communicate with each other and with various systems: Production, development, sales, even suppliers and customers can be integrated into the networked processes. "Smart" factories do not even have to be built from scratch, thanks to retrofitting and brownfield.

iTurning old into new 🤩 The terms retrofitting and brownfield are largely used interchangeably, the latter as a differentiation to the term greenfield: Retrofitting describes the fundamental redesign and conversion of existing machines with intelligent sensor technology to make these machines "smart" and thus ready for the requirements of an automated, networked production. "Smart" generally refers to distinct communication skills (more on this below). The key advantages compared to a new construction (greenfield scenario) are obviously notable cost savings. A brownfield facility is simply an existing factory or production plant (a "brown field" being a field that has already been built on).

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But as tempting as that sounds, it is obvious that automation and networked systems cannot be created by throwing a lever.

We must bring IT and OT together!

Here's a second problem. IT has a counterpart with which it shares the same goals but different approaches. There is no way around this acronym: OT stands for operational technology, and in very simplified terms, it refers to hardware and software that monitors and manages physical equipment and processes.

This brings us back to automation and networked systems, which are in fact OT approaches. OT has obviously been around for a long time, but digitization has made it even more distinct from traditional IT. While IT focuses on interactions between humans and applications, OT focuses on event-based interactions between conditions and process systems. Information might be seen as IT's domain, but information captured by sensors on the floor is OT's business. Now here’s the dilemma: Like IT, OT can get stuff done alone, so there hasn't been much will to converge. That's always been a huge mistake - a mistake that can be fixed!

Differences are also apparent - and this doesn't make things any easier - in organizational and personnel matters: the CIO is traditionally responsible for business applications and the associated IT systems. The operations or production manager, in contrast, is responsible for production control. In the past, personnel overlaps between IT and OT were not planned and usually not even desired.

iOT and IT objectives at a glance 🤓

  • The OT department implements and supports specialized process control systems that ensure continuous availability of applications.
  • The IT department implements and supports extensive communication-oriented and open systems based on standard-based networks and servers.

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The merging of IT and OT is commonly referred to as IT/OT convergence. You could also call it IT/OT collaboration. Operational technology and information technology can complement each other very well in most cases.

Communication, smart gateways, and risks

Due to their isolation, different machines never really had to communicate with the outside world. As a result, proprietary systems and protocols were developed (and are still being used), which are not compatible with classic IT.

On the concept of communication, it is useful to differentiate between horizontal and vertical communication:

  • Horizontal communication could start, for example, directly on the shopfloor (field level with various sensors), using Modbus TCP to query the status of PLC controllers or to read values from them.
  • Vertical communication is the transfer of, for example, data to a higher instance, like from the PLC level to the process control (HMI), the operations management (MES), or the company level (ERP).

iWait, what? 😕 Sorry for all the perhaps confusing terms and the the multi-unit structure, but it can be quickly explained:

  • Shopfloor 👉 The term shopfloor simply means the part of production in which manufacturing takes place.
  • Modbus TCP 👉Modbus is a communications protocol that has been in use since the 70s, and has become standard for connecting electronic industrial devices. Modbus TCP is used for devices connected to a TCP/IP network.
  • PLC 👉 Programmable logic controller (on the control level)
  • HMI 👉 Human-Machine Interface. In practice, these can be touch screens, which allow the display and control of applications and thus the communication with the production plant.
  • MES 👉 Manufacturing Execution System. At plant management level, the collection and processing of data happens here.
  • ERP 👉 Enterprise Resource Planning. A core function of ERP in manufacturing companies is material requirements planning, which ensures all the materials required for the manufacture of the products and components are at the right place, in time, and in the right quantity.
  • Field, control, and process control level are all operational levels and thus part of what we call OT. The operations management level is tactical and the company level strategic; both can be seen as part of classic IT.

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The lost in translation problem happens somewhere between shopfloor and the way up. Smart gateways bring IT and OT together by offering vertical communication; they can be connected to various machines and other elements in a factory, and they are responsible for collecting data and sending them to end points. In order to connect existing systems in a factory to an overall IT application, data must first be converted from their application-specific physical bus systems to open network interfaces. Smart gateways can be connected to various things, such as actuators, sensors, and other control mechanisms. On the other side, the gateway connects to operators, services and manufacturers.

Last but not least, let’s talk about risks: The isolation of production was a useful thing when looking at security. Machines and facilities have traditionally been rather shielded. For some OT specialists of the old school, OT systems that communicate with the outside are still a world gone topsy-turvy. IT/OT convergence means opening up OT in new ways. It requires exposing OT, and this creates risks. Risk can be managed, if you know about it!

So, this was a brief, very un-salesy, un-annoying explanation about Industry 4.0 and IT/OT convergence. If you liked it, or didn't like it, or just want an opportunity to say Hi, leave us a comment.