Adaptive buffer partitioning method for shared buffer switch and switch therefor

A buffer partitioning method for a shared buffer switch which has a plurality of input ports, a plurality of output ports, and a shared buffer, and operates as a common node of a plurality of Virtual Circuits (VCs) having different predetermined service rates, the method for determining whether or not to store a cell, which is newly received through one of the input ports, in the shared buffer comprising the steps of:

• (a) determining a buffer area of the shared buffer, in which the newly received cell is stored, according to a VC to which the newly received cell belongs;
• (b) determining a reference cell discard threshold with respect to the service rate of the VC to which the newly received cell belongs;
• (c) determining a cell discard proportionality constant with respect to the total number of cells stored in the shared buffer and the changing rate, with respect to time, of the total number of the cells;
• (d) determining a cell discard threshold by multiplying the reference cell discard threshold by the cell discard proportionality constant;
• and
• (e) determining whether or not to store the newly received cell in the shared buffer, by comparing the number of cells stored in the buffer area in which the newly received cell is to be stored, with the cell discard threshold.

A shared buffer switch comprising:

• a plurality of input ports for receiving cells from the outside;
• a shared buffer for storing the cells received through the plurality of input ports;
• a plurality of output ports for transmitting the cells stored in the shared buffer to the outside;
• and
• a partitioner which determines whether or not to store the cells, which are newly received through one of the input ports, in the shared buffer with respect to the total number of cells stored in the shared buffer and the changing rate, with respect to time, of the total number of the cells, and according to the determination, stores the newly received cells in the shared buffer, or discard the newly received cells.