Which technology blocks unauthorized or unverified access to network assets?

• A. Antivirus
• B. Firewall
• C. Encryption
• D. Backup Solution

Answer: (B)

Blocking unauthorized or unverified access to network assets is about controlling traffic at the network boundary. A firewall acts as the gatekeeper, inspecting incoming and/or outgoing traffic and enforcing security rules. It can block attempts from untrusted sources, permit legitimate connections, and stop access based on factors like IP addresses, ports, protocols, or even application patterns. Stateful firewalls track active connections, making it harder for unauthorized traffic to slip through and helping protect servers and devices on the network.

Other options serve different purposes: antivirus protects against malware on a device, not general access control; encryption keeps data unreadable if intercepted but doesn’t by itself prevent access to the network; a backup solution focuses on data recovery and availability, not on preventing unauthorized access.