ATM CELL SCHEDULING APPARATUS USING CALENDAR AND METHOD THEREFOR

摘要

PURPOSE: An ATM(Asynchronous Transfer Mode) cell scheduling apparatus using a calendar and a method therefor are provided to enhance switch efficiency by scheduling the transmission of a traffic according to a traffic state of a switch output port when a cell inputted in an ATM switch is switched and by restraining a temporary overload state of the traffic. CONSTITUTION: A VC(Virtual Connection) buffer(20) stores cells by a VC unit, and transmits a storing address of a primary cell among corresponding VC cells. If the storing addresses of the cells are received from the VC buffer(20), a plurality of calendar schedulers(30-33) calculate start times of the cells and store the storing addresses of the cells in corresponding slots. A service scheduling(40) schedules whether a certain storing address of the cell is primarily started among the storing addresses of the cells, which are outputted from the calendar schedulers(30-33). VCQs(Virtual Output Queues)(60-63) read and store cells corresponding to the storing addresses of the cells, which are outputted from the service scheduling(40). A scheduler schedules and outputs the cells stored in the VCQs(60-63) according to the state of an output port and a service level.