Patent Number: 7,356,257

Title: Optical switching apparatus and optical communication network system

Abstract: An optical communication network system is disclosed, which includes an optical switching apparatus. The optical switching apparatus includes an optical switch for switching and setting routes of an optical signal without being converted, a control unit for instructing the optical switch to execute a route switching operation, and a performance monitor for detecting performance of the optical signal having a route set by the optical switch. The performance monitor issues an alarm when the performance detected is deteriorated from predetermined performance. The control unit includes an alarm masking unit for masking the alarm issued from the performance monitor at least for a predetermined masking period from a starting time of a switching operation by the optical switch, and thus preventing the alarm from being issued.

Inventors: Kitajima; Shigeki (Kawasaki, JP), Kakizaki; Sunao (Kawasaki, JP), Tsushima; Hideaki (Komae, JP), Fukashiro; Yasuyuki (Yokohama, JP)

Assignee: Hitachi, Ltd.

International Classification: H04J 14/00 (20060101)

Expiration Date: 2020-04-08 0:00:00