[rrs@learner ~] cat SERVICES/Firewall | less
GNU/Linux has firewalling concept at the core of it's brain, The
Kernel. The Linux Kernel 2.4.x series has excellent firewalling
capabilities, NETFILTER, with rock solid stability and excellent
security. IPTABLES, a part of the NETFILTER project is the base of
firewalling under Linux 2.4.x
Features:-
- IP NAT
- IP Masquerade
- Packet Filtering
- PRE-ROUTING and POST-ROUTING
- Demilitarized Zones
- Port based firewalling
- Host based firewalling