Patent ID: 7650071

Claim:
An optical signal receiver, comprising: a photoelectric converting unit to receive an optical signal containing alarm information and to convert the received optical signal into an electrical signal; a regenerating unit to regenerate a clock signal and data based on the electrical signal obtained by the photoelectric conversion in said photoelectric converting unit and to obtain a regenerated signal comprising the regenerated clock signal and the regenerated data; a transmission speed information acquiring unit to acquire information about a transmission speed of the regenerated signal; a plurality of alarm information extracting units provided in a manner to correspond to each of a plurality of types of transmission methods each providing, at least, a different transmission speed for every different type of transmission method, which extracts alarm information contained in the regenerated signal; and a selection connecting unit to select a corresponding alarm information extracting unit out of said plurality of alarm information extracting units based on the transmission speed information and to connect the selected alarm information extracting unit to said regenerating unit.