An integrated approach to multicasting in ATM switches

We present a new integrated approach for multicasting in ATM switches which takes advantage of both the broadcast approach and copy approach. The multicast cells are first separated from the unicast cells. Then a multicast cell is routed using either the broadcast approach or the copy approach, depending on its number of destinations. Cell replication is done by fan-out without using a copy network. This approach allows fast multicast call set-up, fast additions and deletions of the destinations from an on-going multicast call, supports up to N destinations per call in an N×N switch. It implements multicasting with a minimum amount of memory and, requires a minimum increase in the switch complexity. The paper illustrates the implementation of this technique on a 64×64 three-router sunshine switch architecture and discusses how it can be implemented on other switch fabric configurations