pfSense is a computer software that is developed and distributed by a company called Rubicon Communications, LLC. Chris Buechler and Scott Ullrich started the project in 2004 as a fork of the m0n0wall project and released the first version in 2006. This software is an open source firewall and router computer software that is designed based on the FreeBSD Unix-like operating system. The software is installed on physical computers or virtual machines that provide a dedicated firewall/router for different types of networks. The software is designed to be upgraded through a web-based interface that doesn’t require any underlying knowledge of FreeBSD system to manage.