What are limitations of the RRM channel adjustment function?

What are limitations of the RRM channel adjustment function?

When the DCA algorithm of the RRM is enabled, the system selects an optimal channel and delivers the channel to the AP according to the neighbor channel situations. When the AP channels are switched over, the STA is offline for a short period of time.

By default, the DCA function of the RRM is performed only during 02:00–04:00. If the DCA operation period is changed to 20 minutes in the daytime or the DCA operation is frequently performed during the daytime, user experience is greatly affected. It is recommended that the default configurations of the RRM remain unchanged.

Deployment limitations
When the dual-AC hot backup is deployed, the automatic RRM channel and power adjustment should be disabled. You can manually set the AP channel and power.

Multi-WLAN deployment limitations
When 32 WLANs are configured, the management packets cannot be sent out but accumulated in the transmit queue. In addition, certain network adapters are difficult to be associated.
Network causes: When 32 WLANs are configured, the AP sends 32 Beacon frames within one Beacon period (320 Beacon packets are sent within 1s). When the STA sends a broadcast detection request frame, 32 detection response frames are replied. Assume that the Beacon frame and detection response frame have 240 bytes (the actual frame size is larger than 240 bytes). Under 1 Mbit/s transmit rate, the management frames sent by the AP require 675 ms, and occupy nearly 70% of the channels. With other AP-related detection response frames, the management frames occupy nearly 80% of the channels.

When the AP replies a detection response frame, the detection response frame and the Authentication frame are considered as management frames and transmitted in the same priority queue. When the channel environment is poor, the detection response frame cannot be transmitted in a timely manner. As a result, the Authentication frame is blocked in the hardware queue, and a delay occurs.
The defined Authentication timeout durations vary with STAs. As a result, certain network adapters cannot be associated, for example, D-Link DWA125.

Therefore, when the network environment is poor and network adapter association is difficult, you can address the issues by optimizing the network in the following aspects:

Setting the rate set: Restrict the low-rate packets to improve the transmit rate of the management frames, and ensure normal network adapter association.
Disabling the broadcast detection response: Reduce the number of management frames to improve the transmit efficiency of the Authentication packets.
Using a clean environment: Check whether the test users can be associated in a shielding room or on a 5G network.
Improving the QoS contention parameters: Improve the channel contention capability of the management frames.