What kind of control would the use of a firewall to filter traffic be categorized as?

The use of a firewall to filter traffic is categorized as a preventative control because it actively works to block unauthorized access and potential threats before they can enter a network. Firewalls monitor and analyze incoming and outgoing traffic against a set of security rules. By restricting access to certain types of traffic based on these rules, firewalls help to prevent attacks and unauthorized access, thereby safeguarding sensitive data.

Preventative controls are designed to stop security incidents before they occur. In the case of a firewall, it acts as a barrier between a trusted internal network and untrusted external sources, effectively preventing harmful traffic from reaching network resources. This proactive approach is a key aspect of maintaining an organization’s security posture, ensuring that threats are mitigated in real-time before impacting systems or data.

Other types of controls, such as detective, corrective, and compensating controls, focus on different aspects of security management. Detective controls are intended to identify and alert on incidents that have already happened, corrective controls aim to fix or mitigate damage after an incident occurs, while compensating controls are alternative measures put in place to achieve security when primary controls are not feasible. These distinctions clarify why the firewall's filtering capabilities align specifically with preventative measures.