CompTIA Network+® Study Guide

15.13. Answers to Review Questions

1. C. Firewalls work by allowing only packets that pass security restrictions to be forwarded through the firewall. A firewall can also permit, deny, encrypt, decrypt, and proxy all computer traffic that flows through it; this can be between a public and private network or between different security domains (or zones) on a private network. You as the administrator set up the rules by which a firewall decides to forward or reject packets of data.

2. A, D. Firewalls work at the application layer or the network layer.

3. B. A network-based firewall is what companies use to protect their private network from public networks. The defining characteristic of this type of firewall is that it's designed to protect an entire network ...