Creating a captive portal that uses RADIUS is not that difficult. You can either use an external RADIUS server installed on a separate computer, or you can use a RADIUS server installed on your pfSense system. If you choose the latter, setup is relatively easy, as FreeRADIUS, an implementation of RADIUS licensed under the GNU General Public License version 2, is available as an installable package. In this recipe, we will install this package and use it as our RADIUS server.