Specifications

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RADIUS Accounting
RADIUS Accounting
The RADIUS accounting feature allows the AP, as a RADIUS client, to save accounting
data on a RADIUS accounting server. The accounting feature stores the time of each user’s
session for billing purposes. Authentication, 802.1x or MAC, must be configured before
accounting can be enabled.
An accounting session begins once a user is successfully authenticated by a RADIUS
server. When accounting is enabled, a user cannot be completely authenticated without also
starting an accounting session. If the accounting session fails to start, an authentication
failure is reported to the user.
The AP sends accounting data to the accounting server on a regular basis, called an interim
update. In addition to the accounting data, the interim update notifies the server if the user
session has ended.
The AP can be configured with a specific interim interval. This value determines how often
the updates are sent to the server. The RADIUS server can override the AP’s interim
interval setting to request updates more frequently. However, the AP has an interim interval
minimum setting. This setting determines the highest frequency that the AP will send
updates regardless of the RADIUS server’s request. For example, the AP interim interval
is set to 30 minutes and the interim interval minimum is set to 10 minutes. If the RADIUS
server request 15-minute updates, the AP will comply. If the RADIUS server requests
8-minute updates, the AP will send updates every 10 minutes.
A session ends when any of the following occurs:
• User logs out or restarts the wireless client
• User roams and the AP has a disassociation
• 802.1x authentication times out (only for users with 802.1x authentication)
A user with MAC-address authentication does not have an idle timeout. Therefore, these
users should log out when done; otherwise, the accounting session remains active.