Iptables is packet filtering and NAT firewall for Linux. Iptables is not part of (it will not work) with FreeBSD.

FreeBSD has three different firewall packages
IPFILTER (also known as IPF),
IPFIREWALL (also known as IPFW),
OpenBSD's PacketFilter (also known as PF).

Take a look at freebsd handbook http://www.freebsd.org/doc/en_US.ISO...firewalls.html