A single switch element of atm switching system and buffer thresholds value decision method

The present invention relates to a threshold value control using the shared buffer occupancy information in the switching element in an ATM switching system, controlled by the threshold value input port of the switching element to create a reverse pressure signal using an input buffering. In a conventional ATM switching system it is assigned a threshold value of each input port to be used as static. However, since the input distribution of the cells input to the input port of the switching system is when varies as was considered at the time of initial setting of the switching system to the cell is growing in a particular input port causes the reverse pressure signal for the input port, the current in that even if the buffer is present in the switch device, the input port was to fall and the yield of cells or because they can not accept the cell. Thus, for the present invention to improve the disadvantages described above, and a buffer threshold value controller for calculating a threshold value that is allowed by the input port from the shared buffer occupancy information for each of the input ports in the switch element, depending on the concentration of the cell It proposes an asynchronous transfer mode switching system of the input ports to each line to increase or decrease of the threshold.