| 摘要 |
PROBLEM TO BE SOLVED: To flexibly adapt to the mode of various kinds of maintenance and operation without increasing the scale of hardware by obtaining the history of a discriminated result indicating whether or not stored control information is the same as extracted control information, and discriminating whether or not the result included in the history is true. SOLUTION: An information extracting means 13 fetches a single optical signal separated by a branching filter means 11, and identifies monitor control information under synchronization obtained by a synchronization controlling means 12, and extracts control information included in this. A preceding information storing means 14 stores the extracted information, and a history means 15 discriminates whether or not the precedingly stored control information is the same as control information extracted by the information extracting means 13, and obtains the history of the result. A redundancy discriminating means 16 discriminates whether or not the result included in this history is true across the prescribed number of times, and when the result of the discrimination is true, the extracted control information is applied to maintenance or operation as true control information. |
