What is a key benefit of network segmentation in an industrial control system environment?

• A. It allows unrestricted access for all users.
• B. It ensures no monitoring is needed.
• C. It limits lateral movement of attackers, protects safety-critical networks, and simplifies monitoring.
• D. It eliminates the need for any physical security measures.

Answer: (C)

Network segmentation in an industrial control system environment helps contain breaches by dividing the network into zones with restricted communication between them. The key benefit is that it limits lateral movement of attackers, so compromising one segment doesn’t easily allow access to safety-critical networks or essential control devices. It also makes monitoring more effective, since security tools and logging can be tailored to each zone, making anomalies easier to detect and respond to. In practice, segmentation reduces the impact radius of incidents and simplifies incident response by introducing architectural barriers between IT and OT functions and between general network traffic and safety-critical operations. Physical security remains important, and monitoring is still needed, but segmentation directly supports containment, protection of critical control networks, and clearer oversight.