iSACA Cybersecurity Fundamentals Certification Practice Exam

What is a packet-filtering firewall primarily designed to do?

1. Track user behavior

2. Examine each packet for passage determination

3. Encrypt data packets

4. Prevent all forms of traffic

The correct answer is: Examine each packet for passage determination

A packet-filtering firewall is primarily designed to examine each packet that attempts to pass through it and determine whether to allow or block that packet based on pre-defined security rules. This process involves analyzing attributes such as source and destination IP addresses, protocol types, and port numbers, enabling the firewall to make informed decisions about whether a packet complies with the organization's security policies. The primary purpose of packet filtering is to create a barrier between a trusted internal network and untrusted external networks, such as the Internet, without the complexity or overhead associated with more advanced firewall techniques. By filtering traffic at a packet level, this type of firewall can efficiently allow legitimate traffic while blocking unauthorized access or potentially harmful transmissions. In contrast, tracking user behavior focuses on monitoring and analyzing individual user activities rather than packets of data. Encrypting data packets pertains to securing data in transit by converting it into an unreadable format, which is a different function that packet-filtering firewalls do not perform. Preventing all forms of traffic would defeat the primary role of a firewall, which is to regulate and control traffic rather than block it entirely.