Cisco Systems Servers Benutzerhandbuch

The third-party RADIUS server must return Microsoft Point-to-Point 
Encryption (MPPE) keys in the Microsoft RADIUS vendor-specific attribute 
(VSA) MSCHAP-MPPE-Keys (VSA 12). If the third-party RADIUS server 
does not return the MPPE keys, the authentication fails and is logged in the 
Failed Attempts log.

Cisco Secure ACS support RADIUS-based group mapping for users 
authenticated by LEAP Proxy RADIUS Server databases. For more information, 
see the 

You should install and configure your proxy RADIUS server before configuring 
Cisco Secure ACS to authenticate users with it. For information about installing 
the proxy RADIUS server, refer to the documentation included with your 
RADIUS server.

To configure LEAP proxy RADIUS authentication, follow these steps:

In the navigation bar, click External User Databases.

Click Database Configuration.

Result: Cisco Secure ACS displays a list of all possible external user database 
types.

Click LEAP Proxy RADIUS Server.

Result: If no LEAP Proxy RADIUS Server configuration exists, only the Database 
Configuration Creation table appears. Otherwise, in addition to the Database 
Configuration Creation table, the External User Database Configuration table 
appears.