Extended multicasting technique to allow multiple destinations per output port in ATM switches

When a multicast cell at an aynchronous transfer mode (ATM) switch requires distribution of its copies to the multiple users and/or outgoing sub-rate links served by one of its output ports, multiple cell copies at that output port are required. The conventional copy approach and broadcast approach of multicasting either cannot handle such situations or handles at the cost of switch performance. In this letter we propose a technique to enhance the ability of the copy and broadcast approaches to multicasting to enable them to handle such situations efficiently and economically.