Commenting a firewall
iptables is a command implemented in the 2.4.x kernel series, and is provided as a replacment for the old, and now rather obsolete 'ipchains' from the 2.2.x kernel.
ptables basically represents a set of rules for making your own firewall, by seting your own, or by using pre-made rules. More information about the iptables command can be found by typing 'man ipchains' or by clicking here.
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