Cisco Cisco Access Registrar 3.5 - Manual (Page 25)

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Cisco Access Registrar 3.5 Concepts and Reference Guide
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Chapter 2 Understanding Cisco Access Registrar
Program Flow
Session Management
The Session Management feature requires the client (NAS or proxy) to send all RADIUS accounting
requests to the Cisco Access Registrar server performing session management. (The only exception is if
the clients are USR/3Com Network Access Servers configured to use the USR/3Com RADIUS resource
management feature.) This information is used to keep track of user sessions, and the resources allocated
to those sessions.
When another accounting RADIUS server needs this accounting information, the Cisco Access Registrar
server performing session management may proxy it to this second server.
Table 2-5 describes how Cisco Access Registrar handles session management.
Table 2-5 Session Management Processing
Failover by the NAS and Session Management
When a Network Access Server’s primary RADIUS server is performing session management, and the
NAS determines the server is not responding and begins sending requests to its secondary RADIUS
server, the following occurs:
Determines whether to
perform authorization. The Service name defined in
/Radius/DefaultAuthorizationService, if different than
the Authentication Service.
*Executes the
Service’s incoming
script. A script referred to in
/Radius/Services/<Name>/IncomingScript.
Performs
authorization. Checks that the Service type is defined in
/Radius/Services/<Name>/<Type>.
*Executes the
Service’s outgoing
script. A script referred to in
/Radius/Services/<Name>/OutgoingScript.
Action Explanation
Action Explanation
Determines whether
to perform session
management. The session management defined in the Environment
dictionary variable Session-Manager.
The session management name referred to in
/Radius/DefaultSessionManager.
Performs session
management. Selects Session Manager as defined in
/Radius/SessionManagers/<Name>.
Performs resource
management. Directs the request to the appropriate Resource manager
listed in
/Radius/SessionManagers/<Name>/ResourceManagers/<
Name>, which then allocates or checks the resource
according to the type listed in
/Radius/ResourceManagers/<Name>/<Type>.
Sends an
Access-Accept. Creates and formats the response, and sends it back to the
client (NAS).