Patent ID: 6775287
Filing Date: 2004-08-10
Classification: H04L

Abstract:
An ATM (Asynchronous Transfer Mode) exchange device comprising:a cell multiplex circuit for multiplexing a cell inputted from a plurality of input ports to each fixed time slot during input cell period; a time division multiple bus for distributing the cell which is subjected to time division multiplexing by said cell multiplex circuit among a plurality of routes; a plurality of address filters corresponding to output port for picking only cell whose own port address agrees with output port number, and which cell is unicast cell undergoing routing for single output port from among the cells distributed from said time division multiple bus; a plurality of output buffers for accumulating the cells passed through said each address filters respectively to output to corresponding output port while synchronizing with output cell period; a multicast cell filter for picking a multicast cell for performing routing for a plurality of output ports from among the cells distributed from said time division multiple bus; a bit map table for storing therein multicast output port information indicating output port of said multicast cell; and a multicast cell buffer for accumulating multicast cells passed through said multicast cell filter, before taking out multicast output port information of the multicast cell accumulated while referring to said bit map table in every said output cell period to output to corresponding a plurality of output ports.