Optical switching board implementing wavelength routing supervision for optical cross-connects in WDM OTN

This paper proposes and demonstrates two supervision schemes to monitor wavelength routing for optical cross-connects (OXCs) in WDM optical transport networks. The influence of the supervision methods on the differential loss of the OXC is studied. Experiments demonstrate that an alarm can be sent out immediately by the supervision circuit when errors occur in the optical switches. Guard time protection is introduced to the supervision circuits to prevent them from sending an alarm by mistake. These supervision schemes can be used in the optical layer management for fault detection and network restoration.