CompTIA Network+® Study Guide

15.9. Summary

In this chapter, you learned a lot about physical and hardware security. We dove into this increasingly important subject by looking at one of the most useful network protection devices around: firewalls. You found out the differences between network-based versus host-based firewalls and then learned the specific ways that firewalls work to protect our data and networks by using access control lists (ACLs). You also learned about other key firewall topics like demilitarized zones (DMZs), protocol switching, packet filtering, and proxy services. I talked about how firewalls can operate at the Network layer or the Application layer of the OSI model. For those operating at the network level, there are stateful firewalls that keep ...