Extending the secure edge

Engineers who are tasked with developing solutions for industrial control systems have probably never before seen significant cyber security requirements at the device level with traditional methods for securing industrial control systems relying on limiting access to networks and devices, and monitoring network traffic through information technology (IT) solutions. 

A product lead working on devices in a factory will find it easy to dismiss cyber security as an IT problem. However, the traditional methods for securing industrial control systems will no longer be sufficient in an Industry 4.0 scenario. Companies need to have a strategy to address device security at the edge to ensure that the challenges posed by ICS cyber security do not slow down Industry 4.0 adoption.

While ICS cyber security standards and guidelines are in place, or are being established to secure the factory, they do not provide guidance on how to accelerate Industry 4.0 initiatives. Analog Devices has a mission to enable its customers to more rapidly adopt Industry 4.0 solutions by extending the secure edge and making it easier to implement security.

The very nature of Industry 4.0 is to increase access and accessibility of control of the devices in the factory. This requires increased access to data to expand transparency, reduce network planning, lower CapEx, reduce OpEx, improve bandwidth, and optimise machine interworking. However, it this increased access and accessibility of control that is changing the cyber security risk assessment of the factory system. ICS cyber security solutions need to adapt quickly to address the changing risk, and traditional countermeasures applied to the system – such as firewalls and placing a device behind a locked door – are counterintuitive to the goals of Industry 4.0. This means that devices need to be security hardened to enable increased functionality in a secure method. Identity and integrity will be at the core of every device in the field to enable trusted data and secure operation.

There are a variety of  standards in the industrial market that provide guidance on implementing security in industrial control systems. IEC 62443, for example, is a security standard in draft form for the international market with governance in Europe while in the US NIST provides security guidance. 

These are two of the most predominant standards, providing useful guidelines for implementing security and assessing one’s security posture for industrial control systems; however, they do not provide guidance on how to accelerate the adoption of Industry 4.0. IEC 62443 currently offers no guidelines for implementing security below the PLC and an ISA99 working group has recently been established to address cyber security at the bottom layers of the factory within the IEC 62443 framework. 

Today, to meet an acceptable security posture of a system, countermeasures must be applied to devices that do not reach a sufficient level of security. These countermeasures typically rely on methods such as firewalls to limit access and section off or isolate vulnerable devices. In the future, devices will need to reach higher security levels to enable the transition to Industry 4.0.

The traditional market space occupied by Analog Devices is at the physical edge, where the real world is translated into digital signals and data is born. This gives the company the opportunity to establish trust in data by providing identity and integrity much earlier in the signal chain and establish a new definition of the secure edge. Traditionally, the secure edge has originated at gateways, PLCs, or even servers in the ICS security framework. This view is reminiscent of the traditional IT cyber security view of the factory but it persists throughout the industry.

The prospect of driving the secure edge lower in the signal chain is interesting because it enables higher confidence in the decisions that are being made from that data. The earlier identity and integrity can be established in the signal chain, the more trust and confidence can be placed in the data that is driving decisions.

ICS cyber security cannot be addressed by a one size fits all solution and an in-depth defence approach needs to be adopted and applied based on the risk assessment of the system. Analog Devices has a strategy to extend the depth of ICS cyber security as Ethernet is adopted at the edge. 

Enabling Industry 4.0 requires the factory to adopt new connectivity methodologies. This means that Ethernet has taken, and will continue to take, a larger role in industrial control systems. Analog Devices’ security strategy is to focus on where there is Ethernet connectivity because this significantly changes the impact any one device on the network has on the system. Its current family of industrial Ethernet solutions and TSN solutions has been the focus of security development. In the near term, the fido5000, RapID Platform, which provides two-port, multi-protocol connectivity, will be enabled with security features that provide key generation/management, secure boot, secure update, and secure memory access to protect against network bound attacks. 

The product family roadmap includes single-chip solutions that feature a hardware root of trust, secure device lifecycle management, secure communications/mutual authentication, and tamper protection. As the industry continues to adopt sensors with increased intelligence, connectivity will extend lower in the factory driving additional security requirements at the device level. Analog Devices is committed to developing a secure portfolio that enables easier adoption of ICS security solutions and establish trust at the edge to accelerate the adoption of Industry 4.0.