WLAN QoS setting: WMM vs SSID?
From @akostadinov's answer:
"One can create multiple SSIDs in the router. Then assign a different QoS value for each SSID."
The SSID here means that you'll have the QoS set based on the SSID priority value.
And according to the manual, it's simply that higher number will have higher priority, not 0-1 for background and etc.
Set a name for this SSID. A name is composed of 1–32 characters.
Set the SSID priority ranging from 0 to 7. The default value is 0, indicating no priority is set. A greater value indicates a higher priority."
I found answer in another language (thanks google translate). Basically one can create multiple SSIDs in the router. Then assign a different QoS value for each SSID.
There is a list with the meaning of each priority number, e.g. for video, background, etc. It is not that
x is better or worse than
x+1. So check the table as to what value to set.
On a more careful read I see that from 0 to 7 priority is increasing as Đặng Quốc Trung pointed out.