[plug] Learning/setting up RADIUS

[ryan at is.as.geeky.as]

Does anyone have any useful links or docs to assist me in setting up and
understanding RADIUS on a Linux box?

If I can figure it out, I intend to have a Cisco 1720 authenticate VPN
connections via it where I work.  Someone else will set that side up, so
there is some hope still :)

I'm using Debian and have grabbed xtradius, but this is the choice:

radiusd-cistron - Radius server written by Cistron.
radiusd-livingston - Remote Authentication Dial-In User Service (RADIUS)
server
xtradius - Free radius server implementation.
yardradius - YARD Radius Auth/Acct Server

Any particular one I should be aiming at?

My googling has only found instructions on utilising RADIUS with other
packages - not actually setting it up or explaining it well.

Thanks.

Ryan