问题：

[多选]

In order to enhance worker productivity， a Cisco wireless network has been implemented at all    locations. 
Which three statements regarding WLAN are true？（）

A . A WLAN client will operate in half-duplex mode.
B . The Aironet 1230 access point is an example of an access point that operates solely as a lightweight access point.
C . Ad hoc mode allows mobile clients to connect directly without an intermediate AP.
D . WLANs are designed to share the medium and can easily handle an increased demand of channel contention.
E . A lightweight AP receives control and configuration from a WLAN controller to which it is associated.
F . Another term for infrastructure mode is independent service set （IBSS）.