An optical switch for fast cell-switching networks comprises an optical interconnection network and an electrical control network. In order to fully exploit optical component capabilities and to overcome the constraints imposed by operating speed limits of electronic components, each input of the interconnection network is associated with components which form aggregates of cells which are to follow a similar path through the interconnection network and time-compress the aggregates, and each output is associated with components for the time expansion of the aggregates and separation of the aggregated cells.