See also Firewall | OpenBSD


Home Page:

Acronym: Packet Filter

License: BSD license (revised)

An open-source firewall/packet filter for *Nix, created by Daniel Hartmeier. Since OpenBSD 3.1 it has been the the default firewall for OpenBSD, which is also the development platform. Ports for NetBSD and FreeBSD exist as well.

The development of PF was started in silence after Darren Reed, the author of IPF, claimed his license was misinterpreted which led to additional, non-Free restrictions on the software. The discussion led to a huge flame war that stopped after Daniel Hartmeier announced PF.

AltQ is integrated with PF as of version 3.3 of OpenBSD. Support for transparant Squid and Spamd (tarpitting) is also available on

PF provides numerous advantages over IPTables, the default firewall for Linux. For more information, see the home page of PF and the links hereunder.


TakeDown.NET -> “PF