Methods and systems for automated health assessment of fiber optic links of a fiber optic communication system are described. Tables are used to describe the fiber optic links, including access addresses to communication modules used in the links. Telemetry data representative of operation of the communication modules can be read via the access addresses into a central station. OTDR/OFDR measurement data of fiber optic segments used in the links can be read via the access addresses into the central station. The telemetry and/or OTDR/OFDR measurement data can be used by the central station for comparison against reference data to assess health of the links. The communication modules locally and continuously capture the telemetry data to detect transient events that may be the result of tampering of the links.

Various example embodiments for supporting supervision in optical communication systems are presented. Various example embodiments for supporting supervision in optical communication systems may be configured to support supervision of an optical path including a remote optically pumped amplifier (ROPA) and, thus, supervision of the ROPA. Various example embodiments for supporting supervision of an optical path including a ROPA may be configured to support supervision of the optical path including the ROPA based on a pair of optical supervisory paths configured to extract a pair of optical supervisory signals from an optical path in a first direction and to insert the pair of optical supervisory signals into an optical path in a second direction. Various example embodiments for supporting supervision of an optical path including a ROPA may be configured to support supervision of the optical path including the ROPA based on a pair of optical time-domain reflectometer (OTDR) paths.

A method, an apparatus and a device for detecting an optical module, and a storage medium are provided. The method includes: constructing insertion loss ranges meeting an insertion loss specification that respectively correspond to different signal frequencies in a predetermined signal frequency range, to construct a target insertion loss region; acquiring a microstripline length, a stripline length, a via number and a connector number of a to-be-detected optical module; inputting the microstripline length, the stripline length, the via number and the connector number to a pre-constructed first model, to determine an insertion loss curve of the to-be-detected optical module in the signal frequency range; and determining that the to-be-detected optical module is unqualified if a part of the insertion loss curve is outside the target insertion loss region.

An apparatus includes a reconfigurable optical add/drop multiplexer (ROADM) having an input port to receive a first optical signal from a second device. The ROADM also includes a first wavelength selective switch (WSS), in optical communication with the input port, to convert the first optical signal into a second optical signal, a loopback, in optical communication with the first WSS, to transmit the second optical signal, and a second WSS, in optical communication with the loopback, to convert the second optical signal to a third optical signal and direct the third optical signal back to the second device via the input port.

Devices, computer-readable media and methods are disclosed for determining reachability for a wavelength connection in a telecommunication network. For example, a processor deployed in a telecommunication network may calculate a fiber loss on a link in the telecommunication network using optical power measurements and determine that a destination node of a wavelength connection is not reachable via a path that includes the link based upon the fiber loss of the link that is calculated. In one example, the determining is based upon a number of links in the path, an effective fiber loss for each link in the path, a penalty for nodes in the path, and an acceptable loss value. The processor may further perform a remedial action in response to determining that the destination node of the wavelength connection is not reachable via the path.

Since safe utilization of an optical transmission system is impaired if a system is adopted in which a wavelength band is divided into sub-bands and a different user is allocated to each sub-band, the optical signal monitoring device of the present invention includes: an optical signal information generating means for monitoring wavelength multiplexed signal light comprising sub-band optical signals belonging to each of a plurality of sub-bands classified by means of identification information, and generating wavelength multiplexed signal information including optical power information of each wavelength in the wavelength multiplexed signal light; a sub-band signal information generating means for generating sub-band signal information associated with the identification information, for each of the plurality of sub-bands, on the basis of the wavelength multiplexed signal information; and a sub-band signal information control means for controlling the utilization of the sub-band signal information, on the basis of the identification information.

A derivation method is a derivation method performed by a communication system, including: a transmission step of transmitting a first radio-wave signal according to an optical signal with a first wavelength and a second radio-wave signal according to an optical signal with a second wavelength; a communication start time information acquisition step of acquiring information on a first communication start time and information on a second communication start time; a reception time information acquisition step of acquiring information on a first reception time that is a reception time related to the first radio-wave signal, and information on a second reception time that is a reception time related to the second radio-wave signal; and an optical fiber length derivation step of deriving a length of the optical fiber, based on the first communication start time, the first reception time, the second communication start time, the second reception time, a group velocity or a group delay time of the optical signal with the first wavelength, and a group velocity or a group delay time of the optical signal with the second wavelength.

Techniques for identifying sources of degradations within a PON include detecting a degradation pertaining to a segment of the PON and comparing the drift over time of an optical profile of the segment with respective drifts over time of optical profiles of one or more other PON segments, where pairs of segments share respective common endpoints and an optical profile of a segment corresponds to the characteristics of optical signals delivered over the segment (e.g., attenuation, changes in frequencies, changes in power outputs, etc.). The differences between the compared drift(s) over time are utilized to narrow down the candidate components (e.g., segment endpoints, optical fibers, etc.) for the source of the degradation, and may be utilized to particularly identify a particular endpoint or optical fiber as being the source. The source of the degradation may or may not be a component of the segment to which the degradation pertained.

An optical add/drop multiplexer includes: a first wavelength selector configured to output an optical signal of each wavelength of an inputted first wavelength multiplexed signal while selecting a path for each wavelength; a measurement circuit configured to measure optical power of an inputted optical signal; and a second wavelength selector including a circuit configured to output an optical signal of each wavelength of the first wavelength multiplexed signal while selecting a path for each wavelength, in place of the first wavelength selector when an abnormality occurs in the first wavelength selector, and a circuit configured to output an inputted second wavelength multiplexed signal for each prescribed wavelength unit to the measurement circuit when the first wavelength selector normally operates.

An object is to provide an optical transmission apparatus in which dummy lights can be arranged according to an arrangement of optical signals. A plurality of optical signals of different frequencies arranged in a frequency grid are input to a multiplexing unit and the multiplexing unit multiplexes the input optical signals. A dummy light output unit identifies a dummy light to be arranged in the frequency grid based on the plurality of optical signals and outputs the dummy light. A multiplexing unit multiplexes an optical signal multiplexed by the multiplexing unit and the dummy light output from the dummy light output unit to output a wavelength-multiplexed optical signal L.