Interim accounting
An interim accounting update is a RADIUS accounting message that
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reports changes to key session parameters such as DHCP, HTTP, IP, or roaming state
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is sent by the network access server (NAS) to the RADIUS server between the start-stop accounting messages, and
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can be triggered by specific events or at periodic intervals.
![]() Note |
The RADIUS accounting requests send data, such as VLAN ID, authentication methods, and so on, to a session. |
RADIUS accounting covers these updates:
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Interim Updates: When RADIUS accounting covers DHCP_TLVs, HTTP_TLVs, IP, or ROAM (state machine) changes, the updates are referred to as interim updates or interim accounting.
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Periodic Updates: When RADIUS accounting is specified by a timer value, the updates are referred to as periodic updates.
Disable the interim updates for these reasons:
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These actions increase network congestion by sending unneeded traffic.
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They drive up error rates.
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They impact alarm thresholds and other metrics that are used for venue-authentication performance.
By default, the interim accounting feature is enabled with the aaa accounting Identity default start-stop group radius command.

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