Performance analysis of a hybrid optical switch

To cope with ever-increasing traffic demands in transport networks, all-optical switching is currently perceived as a solution to remove bottlenecks imposed by O/E/O conversions during data transfer. The successful realization of this concept is in large part dependent on the optical switch, which must support a wide range of traffic patterns, while remaining feasible to build both in an economical and practical sense. In this paper, we show a generic design for a hybrid optical switch composed of both slow and fast switching fabrics, and present a performance analysis to provide deeper insight in its behaviour. To this end, we propose and evaluate scheduling algorithms required at the edge of the network to map traffic on the different portions of the core switch, and present a simulation analysis covering a wide range of traffic parameters and switch design choices. These results show the effectiveness of the hybrid switch in catering for short-lived circuits (bursts) by only a limited amount of costly high-speed switching components.