Embodiments of the present invention are directed to optical multiprocessing buses. In one embodiment, an optical broadcast bus (100) includes a repeater (106), a fan-in bus (102) optically coupled to a number of nodes and the repeater, and a fan-out bus (104) optically coupled to the nodes and the repeater. The fan-in bus (102) is configured to receive optical signals from each node and transmit the optical signals to the repeater, which (106) regenerates the optical signals. The fan-out bus (104) is configured to receive the regenerated optical signals output from the repeater (106) and distribute the regenerated optical signals to the nodes. The repeater (106) can also serve as an arbiter by granting one node at a time access to the fan-in bus.