Abstract. The paper aims at depicting certain limitations of EDCA queues related to the different traffic classes. Through simulation, we show main flaws of identical, medium size, Drop Tail queues used by default for each class, with reference to different traffic category's requirements. We propose some substitutes such as differentiated, basically smaller buffer sizes and Active Queue Management mechanisms that can be employed to improve the overall performance. We present a strategy for EDCA queues to maintain the desired quality of transmission for traffic belonging to different categories.