Draytek VigorAP 903 User Manual page 67

Open Wireless LAN (2.4GHz)>>Band Steering to get the following web page:
Available settings are explained as follows:
Item
Enable Band Steering
After finishing this web page configuration, please click OK to save the settings.
Description
If it is enabled, VigorAP will detect if the wireless client is capable of
dual-band or not within the time limit.
Check Time.... – If the wireless station does not have the capability of
5GHz network connection, the system shall wait and check for several
seconds (15 seconds, in default) to make the 2.4GHz network connection.
Specify the time limit for VigorAP to detect the wireless client.
5GHz Minimum RSSI – The wireless station has the capability of 5GHz
network connection, yet the signal performance might not be satisfied.
Therefore, when the signal strength is below the value set here while the
wireless station connecting to VigorAP 903, VigorAP will allow the client to
connect to 2.4GHz network.
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