[ns] Question about WLANs

[Haibo XIE]

Hello every:

There's my question about WLANs' operation.
In one BSS depicted as follows:
A -----AP
       |
       B
A and B are both mobile station and each radio range can overlay another
station. AP is the access point.
A has some data need to be send towards B. Do these messages need be relayed
by AP? Or these messages can be transmitted directly from A to B.