(ISC)2 Certified in Cybersecurity Practice Exam

What device might block or allow network traffic entering an organization's internal IT environment?

1. Turnstile

2. Fence

3. Vacuum

4. Firewall

The correct answer is: Firewall

A firewall is a critical security device that is designed to monitor and control incoming and outgoing network traffic based on predetermined security rules. Firewalls act as a barrier between a trusted internal network and untrusted external networks, such as the internet. By employing various filtering methods, firewalls can block or allow data packets based on criteria like IP addresses, domain names, protocols, and port numbers. This capability is crucial for protecting sensitive internal data and ensuring that only legitimate traffic is permitted to enter or exit the organization’s IT environment. In contrast, the other options do not serve the same purpose in the context of network security. A turnstile primarily serves as a physical access control mechanism, allowing individuals to enter secured areas one at a time while preventing unauthorized entry. A fence also acts as a physical barrier to deter intruders but does not have the capability to manage or control network traffic. A vacuum, while a tool for cleaning, has no relevance in the context of network traffic management. Therefore, the firewall stands out as the essential device for controlling network traffic within an organization.