Refer to the following sources for additional information on packet filtering with iptables.
Section 2.5, “Firewalls” — Contains a chapter about the role of firewalls within an overall security strategy as well as strategies for constructing firewall rules.
2.6.6.1. Installed IP Tables Documentation
man iptables — Contains a description of iptables as well as a comprehensive list of targets, options, and match extensions.
