Normally there are 2 important timers when it comes to Apple devices.
The idle user timeout and the session timeout. Specific to the idle user timeout. If devices dont pass any traffic in 300 seconds (5 minutes) the WLC will delete the client record. This will cause the user (guest) to get the guest page again.
Thats the reason we need to use sleeping client feature:
http://www.borderlessccie.net/?p=220
Regards
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