What is a preventive control in cybersecurity?

Preventive controls in cybersecurity are proactive measures designed to stop security threats before they can cause harm. This is primarily achieved by implementing barriers or safeguards that deter unauthorized access and the exploitation of vulnerabilities. Firewalls are one of the prime examples; they act as a barrier between secure internal networks and untrusted external networks, filtering incoming and outgoing traffic based on established security rules. Encryption is another critical preventive control, as it secures sensitive data by encoding it, rendering it unreadable to unauthorized users.

The focus of preventive controls is on anticipating threats and implementing strategies that mitigate the risk of those threats materializing. This contrasts with other options that involve reactive measures, such as incident response plans which are designed to address security breaches after they occur or monitoring tools that are utilized to investigate issues post-breach. Hence, the emphasis on actively blocking threats beforehand clearly defines the nature of preventive control in cybersecurity.