Non destructive scanning while connected to current AP.

[Ajeet Nankani]

I want to know that when a STA is connected to AP and is actively 
transferring and receiving data from AP, and during that when STA tries 
to scan network non-destructively then what happens to current data 
transfer while scanning, because for scanning, channel needs to be 
changed for active probes, so what happens with the current data frames 
from current channel?

are they lost? or buffered at STA and at AP both? and if buffered, do 
STA indicates AP to buffer frames by sending PS frame to AP or some 
other procedure?

-ajeet.