iptables: iptables (IP packet filter administration) iptables: iptables: iptables is a packet filter administration tool. iptables: iptables: Iptables can be used to build internet firewalls based on stateless iptables: and stateful packet filtering, use NAT and masquerading for sharing iptables: internet access if you don't have enough public IP addresses, use NAT iptables: to implement transparent proxies, aid the tc and iproute2 systems iptables: used to build sophisticated QoS and policy routers, do further packet iptables: manipulation (mangling) like altering the TOS/DSCP/ECN bits of the IP iptables: header, and much more. See: http://www.netfilter.org