WIPFW
FreeBSD has three firewalls built into the base system: PF, IPFW, and IPFILTER, also known as IPF.FreeBSD also provides two traffic shapers for controlling bandwidth usage: altq (4) and dummynet (4). ALTQ has traditionally been closely tied with PF and dummynet with IPFW.Each firewall uses rules to control the access of packets to and from a FreeBSD system, although they go about it in FreeBSD Setting up Firewall using IPFW - nixCraft Jun 21, 2008 [HOWTO] FreeBSD 7.x 8.x + IPFW + Brute Force Monitor
Ipfw-classifyd v.1.0 An application layer classifier for FreeBSD's ipfw firewall. PeerSniper v.1.0 PeerSniper allows the complete removal of the PeerGuardian software from your system and resets the ipfw filters to allow acces back to blocked addresses such as apple.com Just run the app, enter your administrator pass, and it will do the rest.
Yosemite firewall: IPFW is gone, Moving t… - Apple Community Nov 08, 2014 Firewall Software - Free Software, Apps, and Games
Like FreeBSD, ipfw is open source. It is used in many FreeBSD-based firewall products, including m0n0wall and FreeNAS. A port of ipfw and the dummynet traffic shaper is available for linux, openwrt and Windows. wipfw is a Windows port of an old (2001) version of ipfw. Procedure. Modify the ipfirewall ruleset and/or its supporting definition files.
Apr 05, 2012 How to Configure Sshguard With IPFW Firewall On FreeBsd