This original Firewall-HOWTO was written by David Rudder, email@example.com. I'd like to thank him for allowing me to update his work.
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. 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 firstname.lastname@example.org
I AM NOT RESPONSIBLE FOR ANY DAMAGES INCURRED DUE TO ACTIONS TAKEN BASED ON THIS DOCUMENT. This document is meant as an introduction to how firewalls and proxy servers work. I am not, nor do I pretend to be, a security expert. I am just some guy who has read to much and likes computers more than most people. 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 Mark Grennan at <email@example.com>.
Even though there were a lot of discussions on comp.os.linux.* over the past year about firewalling, I found it difficult to find the information I needed to setup a firewall. The original version of this HOWTO was helpful but still lacking. I hope this beefed up version of David Rudder's Firewall HOWTO will give everyone the information they need to create a functioning firewall in hours, not weeks.
I also feel I should return something to the Linux community.
Trusted Information System's (TIS) web site has a great collection of documentation on firewalls and related meterial. http://www.tis.com/
Also, I am working on a security project called I am calling Secure Linux. On the Secure Linux web site I am gathering all the information, documemtation and programs you need to create a trusted Linux system. Email me if you would like information.