Independently switchable bidirectional optical cross connects

As the single fiber bidirectional ring network develops, independently switchable bidirectional optical cross connects (IS-BOXC's) that switch each bidirectional optical signal, both independently and simultaneously will be needed. We propose new structures of IS-BOXC's using two different unidirectional optical cross connects. The proposed IS-BOXC's sufficiently suppress the relative intensity noise caused by Rayleigh backscattering and optical reflection.