Multicast performance in shared-memory ATM switches

Inefficient multicasting in shared-memory ATM switches restricts the output rate of cells and therefore reduces the overall performance. This paper proposes multicast schemes that simultaneously expand multiple multicast cells. When a multicast cell is only partially expanded the remaining residue is sent in later cycles (cell-splitting). This paper uses simulations to analyze the steady-state and transient performance of the proposed shared-memory multicast schemes. The proposed adjustments to multicast routing increase the output rate of cells, which dramatically reduces the cell loss rate and substantially reduces the multicast delays. The order of unicast expansion has a large effect on the performance. The returns in performance diminish on further increasing the number of multicast cells that can be expanded.