Basic accounting

Accounting refers to tracking of the consumption of NAS resources by users. Accounting does not only include cost recovery in the form of billing. It can also be used for capacity planning, to generate trend graphs, and to know more about the resource usage at a given point in time. In this chapter, we will see how accounting is done in FreeRADIUS.

FreeRADIUS is a AAA server. AAA in RADIUS can be grouped into two components. One component consists of authorization and authentication, which uses UDP port 1812. The second component is accounting and uses UDP port 1813. These two components function independently of each other. The different listen sections in the radiusd.conf file confirm this. The following is the listen section for accounting:

#  This second "listen" section is for listening on the accounting
#  port, too.
#
listen {
        ipaddr = *
#       ipv6addr = ::
          port = 0
          type = acct
#       interface = eth0
#       clients = per_socket_clients...