Patent ID: 7489625

Claim:
A multi-stage switch comprising: a plurality of ingress switching modules to receive data packets, to switch the data packets, to generate frames from the switched data packets, to combine a plurality of frames into wavelength division multiplexed signals, and to transmit the wavelength division multiplexed signals, wherein at least one of said plurality of ingress switching modules includes a plurality of egress modules and a scheduler; a core switching module operatively connected to receive the wavelength division multiplexed signals from the plurality of ingress switch modules and to switch the wavelength division multiplexed signals; and a plurality of egress switching modules to receive the wavelength division multiplexed signals from the core switch module, to extract the frames from the wavelength division multiplexed signals, to extract the data packets from the frames, to switch the data packets, and to transmit the data packets, wherein at least one of said plurality of egress switching modules includes a plurality of ingress modules, wherein the switch is capable of detecting faulty paths and switching data through fault-free paths, wherein the scheduler includes a first data array that indicates a fault status for the egress modules within the at least one of said plurality of ingress switching modules and a second data array that indicates a fault status for the ingress modules within the at least one of said plurality of egress switch modules, wherein the scheduler can deactivate faulty paths based on the first data array or the second data array, and wherein the second array is a two dimensional array indexed by egress switching module and the ingress module within the egress switching module.