With network security becoming such a hot topic, you may have come under the microscope about your firewall and network security configuration. You may have even been assigned to implement or reassess a firewall design. In either case, you need to be familiar with the most common firewall configurations and how they can increase security. In this article, I will introduce you to some common firewall configurations and some best practices for designing a secure network topology. I have also put together a free download that includes Visio diagrams of all the topology examples used in this article.