How does a WLAN controller mark an 802.11 frame for QoS priority when sending it to a lightweight AP?

The WLAN controller marks an 802.11 frame for Quality of Service (QoS) priority by placing the user priority value in the QoS Control field. This is an essential function in managing the transmission of data over a wireless network, especially when dealing with services that require different levels of priority, such as voice, video, and standard data services.

The QoS Control field in 802.11 frames holds critical information that allows both the access point (AP) and the devices connected to it to understand how to prioritize the transmission of this data. By including the user priority value, the WLAN controller effectively informs the lightweight AP how to handle that particular frame. This system ensures that high-priority traffic receives the bandwidth and resources it needs for optimal performance while lower-priority traffic can be transmitted when the necessary resources are available.

This functionality is crucial for maintaining a well-performing WLAN, especially in environments with multiple types of traffic. The other options do not accurately reflect the capabilities of the WLAN controller in this context, as they misrepresent the roles and functions involved in marking frames for QoS.