OPNsense is an open-source, FreeBSD-based firewall and routing software. It is a fork of pfSense, which in turn was forked from m0n0wall, which was built on FreeBSD. OPNsense has a web-based interface and can be used on the x86-64 platform. Along with acting as a firewall, it has traffic shaping, load balancing, and virtual private network capabilities, and others can be added via plugins.