When deciding on a firewall implementation, most Unix-savvy administrators have usually chosen to use ipfilter on OpenBSD for their combination of capabilities and stability, as the capabilities of ...

Linux 2.4's Netfilter firewall code and its front end, iptables, deserve the praise and popularity they've garnered. They've brought Linux firewalls to the same level as commercial stateful ...

Nick Gregory, a Sophos threat researcher, found this hole recently while checking netfilter for possible security problems. Gregory explains in great detail his bug hunt, and I recommend it for those ...

For those of you who have taken the plunge and upgraded from kernel 2.2.X (or even 2.0.X) to 2.4.X, congratulations. If, like a number of folks, you're running some form of firewall using either ...

I'm looking to write a Perl program to monitor my network services for intrusion and DOS attempts. I want to take advantage of the INSERT and DELETE options of the "iptables" command. I was hoping ...

This chapter looks at the management of firewalls. From the perspective of the small office/home user, the firewall is a single device that protects the home network from malicious traffic—it keeps ...