RADIUS was designed as an AAA protocol in client/server mode. Enabling dynamic authorization requires that the policy server communicate with the router. Every router vendor implements services using different sets of vendor-specific attributes (VSAs). This means that there is no universal language for sending requests to a router.
To relieve the policy server from the burden of formatting requests in numerous dialects, the IMS AAA server, acting as an intermediary, translates policy server requests to the router. To achieve this, the IMS AAA server uses an XML file that defines services that the router activates and deactivates. Juniper Networks supplies a version of this XML file that includes Juniper Networks and Cisco router configurations.
Before You Begin
We recommend you know the details about your router, its language, services, and attributes. Refer to your router's user guide for any information you need. You also must know the basics of XML. If you do not know XML, many good tutorials are available online; for example, www.w3schools.com/xml/default.asp.