Nuxified Forums: Roll Your Own Firewall

“Over the years I have learned how to roll my own firewall
script and call it from /etc directory. Of course, my firewall is
only INPUT based, instead of INPUT and OUTPUT based, but I find
that building an INPUT/OUTPUT based firewall is tremendously
difficult and not really all that necessary if you use good
download practices on your Linux server or PC and/or if you’re
already behind a NAT router (such as a home-based DSL or cable
router or wireless router) or other firewall.

“If you’re scratching your head on what I mean by INPUT and
OUTPUT, then just think about you being inside a house that has a
front door (INPUT), and a backdoor (OUTPUT). When you surf the web,
you first start sending packets of data out your backdoor
(OUTPUT)…”

Complete
Story