The advantages of partitioning multicast transmissions in a single-hop optical WDM network

In a single-hop WDM optical network, a straightforward approach to implemen ting multicasting is to schedule a single transmission to multiple destinat ions so that all of the destinations may receive the same transmission by t uning their receivers to the same channel at the same time. Although schedu ling a single transmission in this manner reduces the amount of transmitter and channel resources being used, it may also place a burden on the receiv ers in the network. If all receivers do not become available at the same ti me, then some receivers may have to wait (and be idle) for significantly lo ng periods of time before receiving the message. In this paper, we investig ate methods for partitioning a multicast group into a number of smaller sub groups and for scheduling a separate transmission for each of these subgrou ps. We show that this approach more effectively conserves and balances the usage of transmitter and receiver resources in the network and may lead to significantly improved system performance over the conventional single-tran smission multicast approach.