A re-configurable channel dropping de-multiplexer comprises an input, an output, a first 1.times.2 optical switch optically coupled to the input, a second 1.times.2 optical switch optically coupled to the output, a plurality of 2.times.2 optical switches optically coupled between the first and second 1.times.2 optical switches, a plurality of inter-switch optical couplings optically coupled between each pair of adjacent optical switches, a plurality of channel band pass filter assemblies, each optically coupled between two optical switches and a plurality of channel drop ports, each channel drop port being optically coupled to a respective channel band pass filter assembly.