Audience

Who should read this tutorial? Although the tutorial is aimed primarily at those who need to build firewalls, large parts of it are appropriate for everyone who is concerned about Internet security. This list tells you what sections are particularly applicable to you: Although this tutorial provides general concepts of firewalls appropriate to any site, it focuses on "average" sites: small to large commercial or educational sites. If you are setting up a personal firewall, you may wish to read just Part I, "Network Security", "Firewall Technologies", and the service chapters appropriate to the services you wish to run. If you are setting up a firewall for an extremely large site, all of the chapters will be useful to you, but you may find that you need to use additional techniques.