Introduction to FreeRADIUS
The developers of FreeRADIUS speak on their product and its development, from the FreeRADIUS web site:
FreeRADIUS is one of the most modular and featureful [sic] RADIUS servers available today. It has been written by a team of developers who have more than a decade of collective experience in implementing and deploying RADIUS software, in software engineering, and in Unix package management. The product is the result of synergy between many of the best-known names in free software-based RADIUS implementations, including several developers of the Debian GNU/Linux operating system, and is distributed under the GNU GPL (version 2).
FreeRADIUS is a complete rewrite, ground-up compilation of a RADIUS server. The configuration files exhibit many similarities to the old Livingston RADIUS server. The product includes support for:
Limiting the maximum number of simultaneous logons, even on a per-user basis
More than one DEFAULT entry, with each being capable of “falling through” to the next
Permitting and denying access to users based on the huntgroup to which they are connected
Setting certain parameters to be huntgroup specific
Intelligent “hints” files that select authentication protocols based on the syntax of the username
Executing external programs upon successful login
Using the $INCLUDE filename format with configuration, users, and dictionary files
Vendor-specific attributes
Acting as a proxy RADIUS server
FreeRADIUS supports the following popular NAS equipment: ...