QoS is a concept to retain your server providing a stable service. To control the bandwidth or data stream pass through between client and server, click advanced setting button next to "QoS" on Network > Standard Routing.
Simply, you need to input User,Ip,From,To,QoS is fine. If Magic Router run as server mode (set in Coding > Router Mode > Server), and user name / password is entered in User.txt, then you can setup QoS for the user. If no user to define, use *.
QoS value will return if the first rule is matched. If none found, it will not control the QoS. Therefore we always add a last rule to control undetected user or ip with limited QoS. QoS is in terms of kByte.
*,*,00:00:00,23:59:59,10
If you do not enable QoS Mapping in advanced setting, it will get the default QoS ONLY. And if you enter nothing inside QoS, it will not control the QoS.