The pfSense project is a free network firewall distribution based on the FreeBSD operating system with a custom kernel and third-party free software packages.
pfSense software, with the help of the package system, can provide the same functionality or more of common commercial firewalls, without any of the artificial limitations. It has successfully replaced every big-name commercial firewall you can imagine in numerous installations worldwide, including Check Point, Cisco PIX, Cisco ASA, Juniper, Sonicwall, Netgear, Watchguard, Astaro, and more.
pfSense software includes a web interface for the configuration of all included components. There is no need for any UNIX knowledge, no need to use the command line for anything, and no need to edit any rule sets manually. Users familiar with commercial firewalls quickly catch on to the web interface, though there can be a learning curve for users not familiar with commercial-grade firewalls.