In recent years, the area of “Operational Technology” – the technology used in manufacturing, in Industrial Control Systems (ICS), SCADA devices, etc. – has gained the attention of Information Security people. This is a logical consequence of the digital transformation of businesses as well as concepts like the connected (or even hyper-connected) enterprise or “Industry 4.0”, which describes a connected and dynamic production environment. “Industry 4.0” environments must be able to react to customer requirements and other changes by better connecting them. More connectivity is also seen between industrial networks and the Internet of Things (IoT). Just think about smart meters that control local power production that is fed into large power networks.
However, when Information Security people start talking about OT Security there might be a gap in common understanding. Different terms and different requirements might collide. While traditional Information Security focuses on security, integrity, confidentiality, and availability, OT has a primary focus on aspects such as safety and reliability.
Let’s just pick two terms: safety and security. Safety is not equal to security. Safety in OT is considered in the sense of keeping people from harm, while security in IT is understood as keeping information from harm. Interestingly, if you look up the definitions in the Merriam-Webster dictionary, they are more or less identical. Safety there is defined as “freedom from harm or danger: the state of being safe”, while security is defined as “the state of being protected or safe from harm”. However, in the full definition, the difference becomes clear. While safety is defined as “the condition of being safe from undergoing or causing hurt, injury, or loss”, security is defined as “measures taken to guard against espionage or sabotage, crime, attack, or escape”.
It is a good idea to work on a common understanding of terms first, when people from OT security and IT security start talking. For decades, they were pursuing their separate goals in environments with different requirements and very little common ground. However, the more these two areas become intertwined, the more conflicts occur between them – which can be best illustrated when comparing their views on safety and security.
In OT, there is a tendency to avoid quick patches, software updates etc., because they might result in safety or reliability issues. In IT, staying at the current release level is mandatory for security. However, patches occasionally cause availability issues – which stands in stark contrast to the core OT requirements. In this regard, many people from both sides consider this a fundamental divide between OT and IT: the “Safety vs. Security” dichotomy.
However, with more and more connectivity (even more in the IoT than in OT), the choice between safety and security is no longer that simple. A poorly planned change (even as simple as an antivirus update) can introduce enough risk of disruption of an industrial network that OT experts will refuse even to discuss it: “people may die because of this change”. However, in the long term, not making necessary changes may lead to an increased risk of a deliberate disruption by a hacker. A well-known example of such a disruption was the Stuxnet attack in Iran back in 2007. Another much more recent event occurred last year in Germany, where hackers used malware to get access to a control system of a steel mill, which they then disrupted to such a degree that it could not be shut down and caused massive physical damage (but, thankfully, no injuries or death of people).
When looking in detail at many of the current scenarios for connected enterprises and – in consequence – connected OT or even IoT, this conflict between safety and security isn’t an exception; every enterprise is doomed to face it sooner or later. There is no simple answer to this problem, but clearly, we have to find solutions and IT and OT experts must collaborate much more closely than they are (reluctantly) nowadays.
One possible option is limiting access to connected technology, for instance, by defining it as a one-way road, which enables information flow from the industrial network, but establishes an “air gap” for incoming changes. Thus, the security risk of external attacks is mitigated.
However, this doesn’t appear to be a long-term solution. There is increasing demand for more connectivity, and we will see OT becoming more and more interconnected with IT. Over time, we will have to find a common approach that serves both security and safety needs or, in other words, both OT security and IT security.