Patent ID: 6934289

Claim:
A cell processing method in an asynchronous transfer mode (ATM) switch comprising: storing unicast cells and multicast cells in a plurality of shared buffers, and storing addresses of the respective cells in address queues; giving respective priorities to the cells stored in the buffer; reading out the cells from the buffer according to the given priorities; and sending the cells read out from the buffer to fan-out ports, and determining the cell to be finally outputted, wherein reading out the cells from the buffer according to the assigned priorities comprises: reading out in a first cycle a highest priority unicast cell from each buffer if one exists and not reading out any multicast cells in the same corresponding buffer; and if during the first cycle, a respective buffer does not include a unicast cell, but includes a multicast cell, reading out the multicast cell during the first cycle even if a multicast cell with a higher priority exists along with a unicast cell in another buffer.