Firewalls have gained great fame recently as the ultimate in Internet Security. Like most things that gain fame, with that fame has come misunderstanding. This HOWTO will go over the basics of what a firewall is, how to set one up, what proxy servers are, how to set up proxy servers, and the applications of this technology outside of the security realm.
Any feedback is very welcome. I am particularly looking for feedback from people who use Macintosh computers, as the information I have on them is scanty. PLEASE PLEASE PLEASE REPORT ANY INACCURACIES IN THIS PAPER!!! I am human, and prone to making mistakes. If you find any, fixing them is of my highest interest. I will try to answer all e-mail, but I am busy, so don't get insulted if I don't.
My email address is drig@execpc.com.
This document is meant as an introduction to how Firewalls and Proxy Servers work. I am not, not do I pretend to be, a security expert. I am just some guy who has read to much and likes computers more than people. I AM NOT RESPONSIBLE FOR ANY DAMAGES INCURRED DUE TO ACTIONS TAKEN BASED ON THIS DOCUMENT. Please, I am writing this to help get people acquainted with this subject, and I am not ready to stake my life on the accuracy of what is in here.
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If you have any questions, please contact David Rudder <drig@execpc.com>.
There were a lot of discussions on comp.os.linux.* over the past year or so asking for Firewalling help. It seemed as if no one was going to answer these. I assumed that the reason was that no one knew how. So, I set aside some time to play with Firewalling and teach myself it. This document is in response to those requests.
The Firewall Toolkit by TIS has a collection of the best
documentation I have found on firewalls and related constructs. For more
on the Firewall Toolkit, look for the section Firewalling
Software.