Patent ID: 7366411

Claim:
An optical transmission system including a plurality of layers, the system comprising: an optical transponder having a digital wrapper, the optical transponder operates to execute maintenance of a received signal in the optical transponder; the optical transponder further including: a digital wrapper interrupt processor for processing an interrupt signal generated from the digital wrapper according to monitoring of the received signal; a defect and maintenance signal detector for determining whether or not the received signal has a defect and determining whether or not the received signal requires maintenance under the control of the digital wrapper interrupt processor; a defect and maintenance signal processor for, when a defect is detected by the defect and maintenance signal detector or is cancelled, processing the defect; and a digital wrapper controller for controlling the digital wrapper according to the processing result of the defect and maintenance signal processor, wherein the plurality of layers includes an optical transport unit layer, an optical data unit layer and an optical channel layer, and the digital wrapper interrupt processor sets a defect mask for each layer and processes an interrupt of each layer when the defect mask is true, and the defect and maintenance signal detector processes the defect mask of another layer to be false so as to ignore processing of a generated interrupt in the case that a defect of the optical channel layer is detected.