Nothing is different on the Cisco side of things. There's a sample config here (http://www.cisco.com/warp/public/110/cvpn3k_pix_ias.html) for IAS to a PIX, don't have one for a router specifically, but the screen shots in this will show you how to configure the IAS server. As I said, on the Cisco side of things it's a standard AAA config.
now I' ve proprly configured the IAS server to perform router's radius vty access authentication.
I'd like to know if someone have already performed both authorization and accounting ? ? ? is possible to creat different user with different router's privilege access on the IAS?
thank's in advance!