Connectivity is at the heart of Industry 4.0 and IIoT implementations, and securing IIoT deployments from cyber-attacks is critical to this. A successful cyber-attack on an IIoT system can result in the loss of sensitive data, interruption of operations, and destruction of systems. Markedly, it may also result in damage to brand and reputation, material economic loss and damage to critical infrastructure. Worse, there could be damage to the environment, injury or loss of human life.
According to Schneider Electric, cyber security should be an ongoing process based on a life-cycle methodology. This starts with assessment, then to design, implementation and finally maintenance. A secure IIoT solution comprises of many elements, including secure products, secure protocols, a secure network, ongoing security monitoring, and employees with cybersecurity expertise.
Secure Protocols
IIoT systems may feature new connection techniques that will need secure communication protocols. It is important to consider two key concepts when discussing secure protocols – encryption and data integrity/authenticity. However, using encryption to secure protocols can inhibit other security appliances like Intrusion Detection Systems. Data integrity and authenticity do not need encryption, enabling intrusion detection systems. Many legacy systems also utilise insecure communications protocols and their identification is also important. Alternatives are available, for example Modbus is evolving into Modbus Secure, likewise with other open networks.
Trust in the supply chain
Trust impactson the supply chain too, requiring regular monitoring to ensure the preservation of trust throughout the product life-cycle. Many smart devices use components and software from several sources, and each has the potential for security issues. End-users must in effect trust in the integrity of the supply chain providing system components.
Securing IIoT deployments
One challenge for small to medium sized companies may have difficulty building cybersecurity expertise for securing IIoT deployments. Their staff may have developed core competencies focused on optimizing manufacturing processes and automation, not cyber security.
Equipment vendors and system integrators can help to provide cost effective cybersecurity expertise. Vendors often merge industrial control and cybersecurity expertise, although many IT based consultants lack OT expertise. Vendors also have the expertise to guide end-users in the selection secure equipment and training.
Cloud computing
Cloud services support using external computing power to analyse and control OT infrastructure. The location of cloud infrastructure can be within the corporate network, or outside the network operated by a partner. Many end-users are implementing an internal cloud model, as housing data on internal equipment connected to a network controlled by the end-user helps to safeguard critical data. Using an external partner creates several trust boundaries that can impact security and privacy. For example, stolen credentials could allow attackers to access critical data.
Securing legacy equipment
Product lifecycle has a huge impact on security in industrial applications. Unlike IT environments, products can remain in active service in industrial control systems for as long as thirty years. Thus, IIOT systems will include legacy end-devices developed before the advent of security standards alongside new end-devices with native security features. It is unrealistic to assume that end-users will update older components when implementing IIOT.
There are two options to mitigate this issue, selection between the two will depend on each application.
Option 1. Limit communication to data collection only. This is the safest option but may not be viable for all applications.
Option 2. Restricting device access. Note that this will need monitoring for the integrity of communications to ensure that data is not changed as it travels between devices. This option is more practicable as limiting access to data collection may not be workable. Devices that have been recently deployed will have security features. In this case users may be able to operate without building security around devices.
Integrating new equipment
If customers choose to update legacy equipment, selecting equipment with firmware and software signing is critical to insure secure patching. They should also lean towards products developed using a secure development lifecycle (SDL). Most organizations have a well-defined process to create, release, and maintain products.
Business risks associated with insecure products highlight the need to integrate security into the development process. Users should ask potential vendors to supply proof that their development centres follow standards such as IEC 62443-4-1. Third party certification of a development process provides confidence that product development used secure practices, reducing potential implementation risk.
Conclusion
Connecting devices to each other and the cloud opens the door for smart processes leading to significant improvements in productivity and efficiency. Importantly, the tools for securing IIoT deployments are in place today, but change will be evolutionary rather than revolutionary, and security will remain a key factor.
