What is a primary characteristic of ICS-specific firewalls?

A primary characteristic of ICS-specific firewalls is their ability to filter traffic based on specific Industrial Control System (ICS) protocols. This capability is crucial because ICS networks often employ specialized communication protocols such as Modbus, DNP3, or OPC, which are not typically used in general IT environments. By focusing on these specific protocols, ICS firewalls can provide targeted security measures that ensure the integrity and availability of control system data while mitigating risks associated with cyber threats that may exploit protocol vulnerabilities.

This differentiation in filtering allows ICS firewalls to operate effectively within the context of industrial environments, where standard firewalls that cater to general-purpose networking might not be equipped to handle the unique requirements of ICS traffic. As a result, ICS-specific firewalls play a vital role in maintaining the security of critical infrastructure systems by ensuring that only legitimate communications occur over the network.