In this article we propose a novel time and warvlength division multiple access (T/WDMA) scheme for a metropolitan area network based on a passiue optical star. This scheme supports circuit-switched trafic in an environment with a large number of users with applications that span a broad range of data rates (' om [loice to full motion itideo). The scheme can be implemented using acoustooptic tunable filters characterized by a relatively large tuning range (around I00 warvlengths) and a relatiuely low tuning speed (around 10 ps). Pe$omance of this scheme is studied by simulation for the uniform, single-rate, point-to-point rrafic case. We also show how the multiwavelength filtering capability of acoustooptic tunable filters can be used to improlie the peq5ormance of the proposed T/WDMA scheme.