What exactly is OT security?

OT stands for Operational Technology. This refers to hardware and software that monitor or control physical processes. Examples include machines on a production line, as well as systems for building management, access control or traffic management.

OT security is to protect those systems against cyber threats. The aim is to prevent unauthorised persons from disrupting their operation, tampering with settings or exploiting vulnerabilities.

In this respect, OT security differs from traditional IT security in a number of ways. In IT, the emphasis is often on protecting data, computers and applications. In an OT environment, however, the physical operation of systems also plays a key role. A security incident could, for example, result in a system failure, a process being controlled incorrectly or safety being compromised.

What is the link between OT security and IoT security?

OT and IoT are often mentioned in the same breath, but the terms do not mean the same thing.

IoT stands for Internet of Things. It refers to physical devices that are connected to a network and exchange data. Examples include smart sensors, cameras, thermostats and other connected devices.

OT refers to technology that monitors or controls physical processes. An IoT device may form part of this, for example when a connected sensor transmits data to a system that regulates the ventilation in a building.

Not every IoT device is therefore automatically an OT system. A smart speaker, for example, is a connected device, but does not necessarily control a critical physical process.

Nevertheless, the security of both is closely interlinked. After all, a vulnerable IoT device can also pose risks to the environment to which it is connected. That is why it is important to look not only at industrial machinery, but also at other devices that form part of your network.

Why OT security is relevant to your business too

Many organisations use devices that are connected to the network and monitor or control physical processes. Examples include traffic lights, medical equipment, smart cameras or systems that keep a building running.

Whilst this technology makes day-to-day work more efficient, it also poses security risks. A vulnerable device can not only disrupt the operation of a system, but in certain circumstances may also act as a gateway to other systems within the company network.

Even if you are not a manufacturing company, it is important to consider the security of connected devices and the processes for which they are responsible.

5 examples of OT you might not expect

You don’t need to run a factory to come into contact with OT. In other sectors, too, there are systems that control or monitor physical processes. Here are a few examples that you might not immediately associate with OT security.

1. Smart cameras and access control

Cameras, badge readers and automatic gates help to secure buildings and premises. They are increasingly connected to a network, enabling staff to manage them remotely or view footage centrally.

But what if such a system is not sufficiently secure? An attacker may be able to view footage, alter settings or disrupt the operation of a security system. Depending on the network connections, a compromised device could also serve as a launching pad for further attacks.

2. Traffic lights and smart infrastructure

Traffic lights, traffic management systems and other smart applications in public spaces rely on technology that controls physical processes.

A cyber incident can disrupt the normal operation of these systems and thus affect traffic flow or safety. It is a clear example of how cybersecurity is not just about digital data, but also about the physical world in which we live.

3. Hospitals and medical equipment

In hospitals, a great many devices and systems are connected to the network. These include medical equipment used during examinations, treatments and operations, as well as systems that support the running of operating theatres.

If such devices are hacked or cease to function correctly, the consequences may go beyond a mere technical fault. Diagnostic tests or treatments may be delayed and, in certain cases, the continuity or safety of care may be compromised. A disruption to the systems on which medical staff rely during an operation can also have serious consequences.

That is why it is important not only to secure the medical equipment itself, but also the network connections and systems with which it communicates.

4. Airports and logistics environments

At airports and in logistics centres, automated systems control a great many physical processes. These include baggage handling, conveyor belts, access control and other systems that ensure everything runs smoothly.

A disruption to such a system can quickly have consequences for other activities. Security measures must therefore take into account not only the individual devices, but also the connections and interdependencies between them.

5. Shops and smart refrigeration systems

In shops, too, OT systems are indispensable for day-to-day operations. Take, for example, refrigeration and freezer units that automatically regulate the temperature and ensure that food is kept at the correct temperature.

The extent of the impact a cyberattack can have on such systems became clear this autumn. In October 2026, hackers tampered with the refrigeration systems of hundreds of French supermarkets. This was followed in early November by a a new wave across seven European countries: in Belgium, at least 76 supermarkets were affected, including branches of Delhaize, Colruyt, Carrefour and Intermarché. The hackers remotely switched the refrigeration and freezer systems to defrost mode, resulting in the loss of large quantities of chilled and frozen products. In France, the damage could run into millions of euros. It is striking that many of the affected systems were directly accessible via the internet, were still using a default password or were running on outdated software.

This example demonstrates that OT security is also important for retailers. A hacked refrigeration system not only causes a technical problem, but can also lead to food wastage, financial loss and disruptions to a shop’s day-to-day operations.

What if a connected device is hacked?

A cyberattack on a connected device can have various consequences. The device itself may be compromised, but the risk does not necessarily end there. There are two key points to bear in mind.

Risk 1: the functioning of physical processes is jeopardised

If an attacker gains access to a system that controls a physical process, they may attempt to disrupt its operation or manipulate its settings.

The potential consequences depend on the application. For example, a fault in a building management system could disrupt the climate control. In the case of a more critical system, an incident could have more serious consequences for safety or business continuity.

Risk 2: a vulnerable device acts as a gateway to your company network

This risk is sometimes overlooked. A device that, at first glance, appears to have little to do with the traditional IT environment may nevertheless be connected to other systems.

Suppose a hacker exploits a vulnerability in a smart camera. If the attacker gains access to that camera, they can then attempt to reach other systems via the available network connections. For example, internal servers, business applications or data not intended for outsiders.

This does not happen automatically. Much depends on the network architecture, access rights and the security measures in place. However, if devices are not sufficiently isolated from one another and from the corporate network, a single vulnerability can become a major problem.

That is why it is important not to view OT and IoT security as isolated entities. The security of connected devices forms part of your organisation’s wider cybersecurity framework.

How do you protect your OT and IoT environments?

Securing your OT and IoT systems starts with knowing which devices are connected to your network and what risks they pose. By following these steps, you can reduce the likelihood of a cyber incident:

1. Make a list of your devices. Ensure you have a clear overview of all OT and IoT devices, their functions and their network connections. This will help you identify which systems require additional protection.
2. Keep OT and IT separate. Network segmentation prevents an attacker from easily moving from a vulnerable device to other parts of your corporate network.
3. Restrict access. Only grant staff and external suppliers access to the systems they need. Secure accounts and connections to strong authentication.
4. Monitor unusual behaviour. By continuously monitoring network traffic and devices, you can detect suspicious activity and potential threats more quickly.
5. Manage vulnerabilities carefully. Bear in mind that software and firmware may be out of date. Test updates in advance, particularly where a system cannot simply be taken offline.
6. Be prepared for incidents. Set out who should take action if a device is hacked or a critical system fails. This will help minimise the impact and enable you to recover more quickly.

VanRoey helps companies to better map out and secure their OT environment. As a certified Nozomi Networks MSSP partner and Fortinet As an expert partner, we combine our expertise with solutions that monitor connected devices and network traffic, identify vulnerabilities and help detect anomalous behaviour. Network segmentation and the protection of the connection between OT and IT are also part of our comprehensive security approach. Would you rather not manage this yourself? If so, we can continuously monitor your OT environment as a managed service, ensuring that any anomalies are quickly identified and addressed.

This will give you a better understanding of potential risks and enable you to identify more precisely which measures your organisation needs to put in place.

OT security starts with understanding

OT security may seem like something only large industrial companies need, but connected devices and systems that control physical processes can be found in far more organisations than you might think.

Whether it’s access control, building management, logistics systems or industrial machinery: it’s important to know which devices are connected to your network, what risks they pose and how to prevent an incident from spreading further.

Would you like to know how well your OT and IoT environments are protected? VanRoey helps you to assess your environment, evaluate risks and determine the appropriate security measures. Book an appointment with our experts for bespoke advice.