Micro-segmentation in OT security refers to the practice of dividing an operational technology (OT) network into smaller, isolated segments or zones to enhance security. It involves creating granular network segments that are isolated from one another, allowing for fine-grained control and containment of network traffic.
With micro-segmentation, the OT network is divided based on various factors such as function, criticality, location, or specific security requirements. Each segment or zone operates independently and has its own set of security policies and controls. Communication between segments is typically restricted and controlled, requiring explicit authorization and validation.
The primary goals of micro-segmentation in OT security are:
- Limit Lateral Movement: By dividing the network into smaller segments, micro-segmentation helps contain potential security breaches. If an attacker gains unauthorized access to one segment, they will face significant barriers when attempting to move laterally to other segments, thus reducing the impact and scope of a potential compromise.
- Reduce Attack Surface: By isolating and segregating OT systems into smaller segments, the attack surface is minimized. If a vulnerability or breach occurs within one segment, it is less likely to affect other segments or the entire OT network.
- Granular Access Control: Micro-segmentation enables finer control over access rights and permissions. Each segment can have specific access policies, allowing only authorized users or devices to interact with the systems within that segment.
- Contain and Mitigate Threats: In the event of a security incident or compromise within a segment, micro-segmentation helps contain the threat and prevent it from spreading to other parts of the OT network. It allows for quicker incident response and mitigates the potential impact of an attack.
Implementing micro-segmentation in an OT network requires careful planning, network design, and configuration. It often involves the use of firewalls, virtual local area networks (VLANs), access control lists (ACLs), or software-defined networking (SDN) technologies to enforce segmentation and control network traffic between segments.
Micro-segmentation is considered an effective security strategy for protecting OT networks, as it adds an additional layer of defense by isolating critical systems and limiting the potential damage caused by a security incident.
