How to limit node maximum speed

thats how wlan works. u cant do much stuff at same time over wlan. depending on how much antennas and the wlan chip / other ap`s only one device can up or download.so the packets floating time shared and u have lags and or bad wlan . wlan is worst for timecritical stuff like games or stream vids /musik. also thats all raw data / brutto . if u hafe an 300 mbit wlan , u will may get real (netto) max. a 150mbit.
may u first read how wlan works : https://de.wikipedia.org/wiki/Wireless_Local_Area_Network
the english wiki site for that is poor.

there is also a difference between wlan and wifi dudes…
sry my bad english
greetz