AbstractWe consider the problem of supporting multipoint communication at the MAC layer of broadcast WDM networks. We first introduce themidticcut rhroughprrt asthe performance measure of interest and we show that it depends on two measures that have previously been considered in isolation, namely, the efficient use of channel bandwidth and wavelength throughput. We then present a new technique for the transmission of multicast packets based on the concept of aLzirninlreceiver, a set of physical receivers which behave identically in terms of tuning. We also demonstrate that the number of virtual receivers naturally captures the performance of the system in terms of multicast throughput. Consequently, we focus on the problem of optimally selecting the virtual receivers to maximize multicast throughput, and we prove that it is Ji'P‐complete. Finally, we present four heuristics of varying degree of complexity for obtaining a set of virtuat receivers that provide near‐optimal performance in terms of multicast through