DEVICE AND METHOD FOR CONTROLLING QUALITY OF SERVICE IN SYSTEM FOR BUFFERING TRANSFERRING AND EXCHANGING QUALITY OF SERVICE IN SHARED MEMORY METHOD

摘要

PURPOSE: A device and a method for controlling the quality of service in a system for buffering transferring and exchanging the quality of service in a shared memory method are provided to service often according to the allotting ratio of bandwidth for each subsidiary queue and to service first of all in case of exceeding a critical value by setting a maximum delaying time per subsidiary queue for each cell passing through each subsidiary queue. CONSTITUTION: The end of service for a subsidiary queue is received for detecting the existence of the subsidiary queue exceeding time. If the time exceeding subsidiary queue is existed, the subsidiary queue is selected for outputting the corresponding cell of the selected subsidiary queue. If the time exceeding subsidiary queue is not existed, the subsidiary queue is selected according to the order stored in a sequence register for port and grade to output the corresponding cell of the selected subsidiary queue.