Hi.
It's obviously different "session timeout" and "inactivity timeout".
Session time is a duration for session after authentication.
It's kind of like a countdown.
If the countdown is finished, you must re-auth.
If you don't re-auth, it remain unauthorize status.
Otherwise, Inactivity timeout is a duration to remain session table after de-authentication or no packet (such as hibernation, power shutdown).
Session timeout can apply some method.
If you use 1X ssid, configure VSA as "session timeout" onto AAA server.
If you use wispr(Hospot), configure session timeout under wispr setting(Hospot).
If you can apply it using Radius CoA.
Thanks.