Technical Tips: Industrial Transition—Achieving Trustworthy Industrial Automation

Brendan O'Dowd

Analog Devices

New technological advances and the desire for more efficient production processes and plants are driving unprecedented changes in industrial facilities. These changes are increasing automation, precision, and the amount of data available.

These advances make Industry 4.0 a reality, bringing greater development prospects and business opportunities to manufacturers, while reducing emissions and enhancing competitive advantages in the global economic environment by improving productivity, safety and reliability. It is estimated that the next 10 years will bring automation equipment manufacturers business opportunities worth about $6.5 trillion.

While the opportunity is attractive, there are significant hurdles to overcome. For example, in traditionally conservative industrial sectors, the adoption of new technologies is often slow. Automated factories are currently often a mix of old and new systems, with complex communications between them. Existing infrastructure has little ability to securely capture and transmit data at the edge of the network. In short, manufacturing plants and process plants will not change overnight. There will need to be a transition period.

To enable and accelerate this transition, automation suppliers are turning to technology partners and suppliers such as ADI for more system domain expertise and solutions.

The transition required for the connected enterprise, especially Ethernet and security

Industrial Ethernet is already widely used in control applications and will continue to expand as the preferred communication medium as businesses and markets transition to Industry 4.0.

One of the challenges is solving the deterministic problem of Ethernet. Many protocols use proprietary Layer 2 solutions. However, these protocols cause a lot of interoperability problems when trying to extract relevant data for use by higher levels of the enterprise network or to coordinate between different manufacturing nodes. The new IEEE 802.1 TSN standard aims to solve the same kind of problems encountered in industrial control and promises to support the transition from proprietary solutions to a standards-based approach.

Ethernet has traditionally been a "best effort" network. In order to deploy Ethernet for mission-critical applications, special features need to be added, including time synchronization, traffic scheduling, flow control, seamless redundancy and other functions. The purpose behind these emerging IEEE TSN standards is to achieve a truly converged network where all categories of traffic in the network can coexist seamlessly. This will allow mission-critical real-time traffic to be transmitted on the same network as streaming and "best effort" traffic. These features allow network designers to ensure that specific categories of traffic are delivered in a timely manner every time throughout the entire network topology. Unlike proprietary Layer 2 solutions, these features are designed to scale to line rates of Gigabit or higher.

Analog Devices recently acquired Innovasic, a major member and contributor to the Industrial Internet Consortium, to support TSN.

Connecting edge devices to a converged, trusted, connected Industry 4.0 enterprise network enabled by TSN presents many challenges. Current communication technologies in edge devices, such as fieldbuses and 4mA to 20mA current loops, work fine and reliably. However, when it comes to getting their data to the cloud (locally or remotely), the path from the factory floor to the front office is often hampered by multiple layers of communication. Gateways are often required to convert from one format or protocol to another, and data may be stored on multiple servers en route to the actual analysis end. The total cost of ownership for getting data from a simple sensor to the cloud involves not only the equipment required to deliver the data, but also the software, processing technology, and manpower required to ensure data integrity along the way.

While connecting Ethernet to a simple device like a temperature transmitter may seem a bit contradictory, this has nothing to do with the simplicity of the device or the relatively little data it produces/consumes. It’s about how data can be effectively extracted from the device on a converged network and then applied to actionable results. For example, a distributed control system (DCS) might use data from a temperature sensor to ensure that part of its process is running in real-time control. However, this specific temperature may also affect the entire process. By seamlessly connecting the temperature transmitter to the cloud, analysis can be performed in near real-time taking into account all process parameters to ensure the entire process is running. Adjustments can be made to optimize production or improve energy efficiency.

ADI sees solving these challenges as critical to our customers’ success, which is what drives us to invest in cutting-edge technology to push Ethernet to the edge. This key technology, which we call Low Complexity Ethernet, is a driver that connects simple industrial devices, such as temperature transmitters, directly to Ethernet.

Figure 1. Single chip, multiple Ethernet protocols.

Low Complexity Ethernet addresses the traditional size, power and cost issues of today’s standard Layer 2 Ethernet implementations, thereby reducing the total cost of ownership for delivering data to the cloud.

The transition to converged Industrial Ethernet networks also requires innovations in the physical layer to provide solutions that match some of the inherent capabilities of existing systems. Many widely deployed Ethernet physical layer standards limit cable lengths to 100 meters and require multiple twisted pair cables to implement. In contrast, most of the existing infrastructure installations for factory automation networks are built with single twisted pair cabling, which is capable of supporting distances of up to 1000 meters at data rates of 31.25 kbps. To address this issue, ADI is collaborating with key industrial partners sponsored by the IEEE to develop a new Ethernet standard. Called 10SPE, the standard will run over a single twisted pair cable, supporting distances of up to 1000 meters at a data rate of 10 Mbps. ADI is taking a collaborative, standards-based approach to address this issue, helping to lower adoption barriers and shorten the time to achieve the goal of converged networking across the entire factory.

In addition to developing new features to support Ethernet convergence, other applications that already use 100 Mbps deterministic Ethernet are looking to push the limits of bandwidth and performance. Applications such as robotics require more and more axes to be controlled with greater precision than in the past. Transitioning control networks to Gigabit speeds helps meet these requirements and represents another major trend in the industrial Ethernet market.

Ethernet's meteoric success often leaves Ethernet users struggling to address security issues related to their applications. The expected growth in data and sensing needs at the edge of industrial networks may be hindered by security risks. In addition, the requirements for low latency and jitter performance in industrial control applications may directly conflict with security requirements. Users of these technologies must quickly address performance and security issues in these applications.

Analog Devices recently acquired the security business unit (SCIOMetrics) of Sypris Electronics

Cybersecurity risks in the industrial sector are increasingly being recognized. Due to the rise of Industry 4.0 and the Industrial Internet of Things (IIoT), the industrial space is defined by widespread distributed devices, dynamic information flows, and cross-environmental interconnection to provide new capabilities. However, it is not surprising that with the creation of new capabilities, it also brings new security threats that have never been seen before and are more real than ever before.

If you imagine the number of devices that must be securely connected to a network, you will understand how difficult it is to establish an identity for these devices. Physically distributed shared encryption keys quickly become impractical, and certificate exchange management turns into a logistical nightmare. Keyless identity establishment is essential to achieving the vision of a trusted Industry 4.0 enterprise. Similarly, lightweight cryptographic technologies with low fixed latency and a small hardware and/or software footprint are needed to securely connect highly constrained devices at the edge of the network. ADI has invested heavily in technologies such as authentication and security solutions for resource-constrained devices and lightweight block cryptography to solve these important problems.

Figure 2. Our key competency is enabling trusted automation.

in conclusion

Analog Devices' Industrial Automation business unit is committed to providing leading solutions in the fields of edge detection, control, monitoring, and robust real-time communication systems for industrial networks. Analog Devices has developed and accumulated expertise in multiple areas, including security and certification, functional and intrinsic safety, and multi-protocol support. Through strong collaboration, we will enable and accelerate the transition to a trusted industrial IoT connected enterprise from sensor to cloud.