m0n0wall 1.8.1 is a small FreeBSD-based operating system designed specifically for firewalls. In m0n0wall 1.8.1, the base system has been switched to FreeBSD 8.4 for better support of recent hardware, and there have been significant improvements, new features and bug fixes in many areas. Change log highlights: add scheduler (Croen) service with many different job types (enable and disable interface or shaper rule, Wake on LAN, reboot, reconnect WAN, execute command); improved IPv6 support, including IPsec, DHCPv6-PD, RDNSS and DNSSL and NDP info on the ARP diagnostic page; major overhaul of wireless LAN support, with some cards, it is now also possible to create multiple APs at the same time; DNS forwarder: add option to log DNS queries, add aliases (CNAMEs) and MXs; make rule moving and deletion on shaper rules page work like for firewall rules; initial support for USB modems..
About Monowall
m0n0wall is a project aimed at creating a complete, embedded firewall software package that, when used together with an embedded PC, provides all the important features of commercial firewall boxes (including ease of use) at a fraction of the price (free software). m0n0wall is based on a bare-bones version of FreeBSD, along with a web server (thttpd), PHP and a few other utilities. The entire system configuration is stored in one single XML text file to keep things transparent. m0n0wall is probably the first UNIX system that has its boot-time configuration done with PHP, rather than the usual shell scripts, and that has the entire system configuration stored in XML format.