P2P Power save

P2P Power save

1. Opportunistic Power save
 Attributes - CT Window
    - P2P GO enters sleep mode only when all the connected CLIs are in sleep (if there is any opprtunity to sleep)
    - CT widnow - Time duarion after TBTT. For this perios GO should be in active state.
    - After CT window, if all the connected clis are in sleep, GO enters into sleep till next TBTT.

2. NOA (Notice of Absence)
Attributes - Count, interval, duration, start time
Count - Count of repetation
Interval - Absence Interval
Duration - GO absence period  within absence interval(it is fraction of absence interval)
Start time - Last 4 bytes of  Starttime TSF
 TSF is 8 byte value
First Absence interval will start when last 4 bytes of TSF match the  4 byte of Start time attribute

   - Period NOA ->
Count > 1, if count=255 then it is repeated infitly till it is explictly stopped
Wrap Around time - since last 4 bytes reappear after 2exp(32) usecs (71 minutes). Spec mandates to updated the start time after every 2exp31 usecs(35.5 minutes)
Used mainly in concurrant mode after STA interface becomes active

  - Non Periodic NOA ->
Count = 1.
Mainly used during during station scan. Absence Duration =  Complete STA scan

Priority of different active and absence periods
1. Absence due to Non periodic NOA
2. Presence for TBTT
3. Presnce for CTWidow
4. Absence due to periodic NOA