Table Of Contents
RADIUS Timeout Set During Pre-Authentication
Prerequisites for the RADIUS Timeout Set During Pre-Authentication Feature
Information About the RADIUS Timeout Set During Pre-Authentication Feature
RADIUS Attribute 27 and the PPP Authentication Phase
How to Configure the RADIUS Timeout Set During Pre-Authentication Feature
RADIUS Timeout Set During Pre-Authentication
Some call sessions for Internet service provider (ISP) subscribers are billed through authentication, authorization, and accounting (AAA) messages in a prepaid time model. When these subscribers are preauthenticated, a RADIUS server checks for any remaining credit in the prepaid time model and sets a session timeout based on the credit available. The RADIUS Timeout Set During Pre-Authentication feature is useful in situations where the PPP authentication that follows the preauthentication phase of these call sessions does not return the Session-Timeout value (RADIUS attribute 27), and therefore allows the ISP to add call setup time to the subscriber's bill.
Feature Specifications for the RADIUS Timeout Set During Pre-Authentication Feature
Feature History Release Modification12.2(15)T
This feature was introduced.
12.2(27)SBA
This feature was integrated into Cisco IOS Release 12.2(27)SBA.
Finding Support Information for Platforms and Cisco IOS Software Images
Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.
Contents
•
Prerequisites for the RADIUS Timeout Set During Pre-Authentication Feature
•
Information About the RADIUS Timeout Set During Pre-Authentication Feature
•
How to Configure the RADIUS Timeout Set During Pre-Authentication Feature
Prerequisites for the RADIUS Timeout Set During Pre-Authentication Feature
•
This feature is specific to RADIUS. Basic AAA authentication and preauthentication must be configured.
•
Preauthentication and normal PPP authentication are required for legacy functionality.
Information About the RADIUS Timeout Set During Pre-Authentication Feature
You need to understand the following concept about the RADIUS Timeout Set During Pre-Authentication feature:
•
RADIUS Attribute 27 and the PPP Authentication Phase
RADIUS Attribute 27 and the PPP Authentication Phase
The RADIUS Timeout Set During Pre-Authentication feature was developed for ISPs that want to bill dial-in subscribers for call setup time and the entire duration of the call session. These subscribers are billed through AAA messages in a prepaid time model. When the subscribers are preauthenticated, a RADIUS server checks for any remaining credit in the prepaid time model and sets a session timeout (in minutes or seconds) based on the credit available. This time can range from a few seconds for ISDN users, to much longer for asynchronous dial-up subscribers.
Until the RADIUS Timeout Set During Pre-Authentication feature was developed, the value of RADIUS attribute 27, which is returned during the preauthentication phase of a call, was either ignored or overwritten during the PPP authentication phase. Even when the PPP authentication phase did not return a value for attribute 27, the old value obtained during the preauthentication phase was being ignored.
With the RADIUS Timeout Set During Pre-Authentication feature introduced for Cisco IOS Release 12.2(15)T, if the PPP authentication phase does not return a value for attribute 27, the old value that was returned during the preauthentication phase is saved and used to time out the session; attribute 27 is saved in a preauthentication database for future use. However, if the PPP authentication user profile has a session timeout configured and PPP authentication succeeds, the new value downloaded during PPP authentication overwrites the old attribute 27 value. By setting the session timeout value in the preauthentication phase itself, the service provider can bill the subscriber for the call setup time and the call duration.
How to Configure the RADIUS Timeout Set During Pre-Authentication Feature
No new configuration is required. The RADIUS Timeout Set During Pre-Authentication feature is included in all Cisco platforms that support preauthentication, and that have RADIUS attribute 27, Session-Timeout, specified in a preauthentication user profile.
Additional References
For additional information related to the RADIUS Timeout Set During Pre-Authentication feature, refer to the following sections:
•
MIBs
•
RFCs
Related Documents
Related Topic Document TitleRADIUS attributes and user profiles
Cisco IOS Security Configuration Guide, Release 12.2. Refer to "RADIUS Attributes" in the Appendixes.
Standards
MIBs
MIBs MIBs LinkNone
To obtain lists of supported MIBs by platform and Cisco IOS release, and to download MIB modules, go to the Cisco MIB website on Cisco.com at the following URL:
http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml
To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:
http://tools.cisco.com/ITDIT/MIBS/servlet/index
If Cisco MIB Locator does not support the MIB information that you need, you can also obtain a list of supported MIBs and download MIBs from the Cisco MIBs page at the following URL:
http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml
To access Cisco MIB Locator, you must have an account on Cisco.com. If you have forgotten or lost your account information, send a blank e-mail to cco-locksmith@cisco.com. An automatic check will verify that your e-mail address is registered with Cisco.com. If the check is successful, account details with a new random password will be e-mailed to you. Qualified users can establish an account on Cisco.com by following the directions found at this URL:
RFCs
Technical Assistance
Command Reference
This feature uses no new and modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.2 T command reference publications.
![]()
Copyright © 2003-2005 Cisco Systems, Inc. All rights reserved.