|OS family||FreeBSD (12.1-RELEASE)|
|Source model||Open source|
|Initial release||2 January 2015pfSenseas a fork of|
|Latest release||20.7 ("Legendary Lion") / July 30, 2020|
|Kernel type||Monolithic kernel|
|License||Simplified BSD / FreeBSD License|
|Community & Commercial|
OPNsense is open source, FreeBSD-based firewall and routing software developed by Deciso, a company in the Netherlands that makes hardware and sells support packages for OPNsense. It is a fork of pfSense, which in turn was forked from m0n0wall, which was built on FreeBSD. It was launched in January 2015. When m0n0wall closed down in February 2015 its creator, Manuel Kasper, referred its developer community to OPNsense. OPNsense has a web-based interface and can be used on i386 and x86-64 platforms. Along with acting as a firewall, it has traffic shaping, load balancing, and virtual private network capabilities, and others can be added via plugins.
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- "WIPO Domain Name Decision: D2017-1828". WIPO. November 12, 2017.