An optical bridge for switching between a plurality of electrical chips, the optical bridge comprising: a passive optical router; and a plurality of Bridge Interface Chips optically connected to the passive optical router; each Bridge Interface Chip being connectable to one of the plurality of electrical chips to form a connection between that electrical chip and the passive optical router at which electrical signals from the electrical chip are converted into wavelength tunable modulated optical signals for transmission to the passive optical router and at which an optical signals from the passive optical router are converted into electrical signals to be received by the electrical chip; wherein each Bridge Interface Chip includes a wavelength tunable laser input and a modulator for modulating the wavelength tunable laser input to provide the wavelength tunable modulated optical signals.

A wavelength cross connect device includes: a wavelength band switching unit configured to receive wavelength multiplexed signal beams each having been transmitted in multiple bands in optical transmission lines each including one or more optical fibers, the wavelength multiplexed signal beams each including multiplexed optical signals of distinct wavelength bands, perform wavelength band conversion on each of the wavelength multiplexed signal beams so as to convert the wavelength bands of the optical signals multiplexed in the wavelength multiplexed signal beam, and output the converted wavelength multiplexed signal beams; and a WXC unit including input-side WSSes that respectively split and output the wavelength multiplexed signal beams output from the wavelength band switching unit, and output-side WSSes mesh-connected to the input-side WSSes. The WXC unit inputs the split wavelength multiplexed signal beams to the output-side WSSes while performing rerouting and outputs the rerouted wavelength multiplexed signal beams to output transmission lines.

A cluster-based distributed optical virtual-circuit-switching network system comprises a tier-1 optical switching network and a tier-2 optical switching network. The tier-1 optical switching network includes a plurality of first-type optical switching network subsystems, each defining a cluster. The tier-2 optical switching network includes at least one second-type optical switching network subsystem, which comprises a plurality of tier-2 optical switches interconnected with one another. Each of the tier-2 optical switches correspondingly connects to one of the first-type optical switching network subsystems. When optical signals are transmitted between the clusters, the signals are transmitted from one of the first-type optical switching network subsystems to another through the tier-2 optical switches of the at least one second-type optical switching network subsystem.