An optical transmission device that transmits an optical signal in a specified wavelength band includes: a receiver, a monitor light unit, a wavelength selective switch and a memory. The receiver receives the optical signal. The monitor light unit outputs monitor light of a wavelength allocated outside of the specified wavelength band. The wavelength selective switch outputs the optical signal via a first port and outputs the monitor light via a second port. The memory stores information that indicates an optical power loss of a route through which the monitor light is transmitted.

A system and method for establishing new line monitoring system (LMS) baseline data compared to which faults are identified in a line monitoring system of an optical communication system. The new LMS baseline is established by injecting fault signature data associated with previous unrepaired faults into LMS current measurement loop gain data.

Systems and methods for performing wavelength conflict detection are provided. These are to detect situations in optical networks where two instances of the same wavelength channel have been added. Wavelength conflict detection is performed for each of a plurality of possible wavelength channels that could be present in an optical signal, each wavelength channel that is present modulated by a pilot tone signal with a respective pilot tone frequency, the pilot tone signal carrying M-ary pilot tone data, M=2.sup.n, n≧1, with a respective one of M different sequences being used to represent each of M possible data values over a data value period. Conflict detection for each wavelength channel involves performing correlation peak detection using each of the M different sequences to determine correlation peaks for each of the M different sequences, and, based on the determined correlation peaks, determining whether multiple instances of the wavelength channel are present in the optical signal.

Embodiments of the present invention disclose a method, an apparatus, and a system for detecting an optical network. The method comprises: receiving, by a management device, a reflection peak power reported by a testing device, where the reflection peak power is a reflection peak power of an optical splitter that is obtained by the testing device according to a reflected optical signal, the reflected optical signal is an optical signal obtained by reflecting, by the optical splitter, a testing optical signal that is sent by the testing device and is transmitted to the optical splitter through an optical cable, and the optical splitter reflects the testing optical signal by using a reflective film disposed on an end surface of one optical output port. a detector does not need to carry a testing device to a site, to perform detection, efficiency of detecting performance of an optical network is improved.

To provide an optical communication technology that brings flexibility to ROADM systems.

An optical communication device according to the present invention drops and adds an optical signal from and to wavelength-division multiplexed optical signals that are transmitted on a main path between network terminal stations, the device including: first means and second means capable of selecting an optical signal of a predetermined wavelength from inputted optical signals and of outputting the selected optical signal; third means for splitting optical signals inputted from a first terminal station on the main path into the first means and the second means; fourth means for splitting optical signals inputted from a branch path in the network into the first means and the second means; and fifth means capable of selectively outputting to a second terminal station on the main path either an optical signal outputted by the first means or an optical signal outputted by the second means.

Methods and apparatuses for optical communications are provided. By way of example, an optical transceiver includes a processing device coupled to a memory, an optical subassembly, and a programmable device. The optical subassembly is configured to receive and modulate a first signal carrying high speed user data for transmission to a remote device over an optical link. The programmable device is coupled to the processing device and configured to receive data relating to digital diagnostic monitoring information (DDMI) of the optical transceiver from the processing device, perform forward error correction encoding on the DDMI data to produce a remote digital diagnostic monitoring (RDDM) signal, and send the RDDM signal to the optical subassembly as a second signal to modulate for transmission. The optical subassembly is configured to current modulate the second signal on the first signal to produce a double modulated optical signal for transmission to the remote device.

Provided is an apparatus of recognizing optical connector connection including an IC tag connection unit configured to provide bus power and detect whether the optical connector is connected to an optical adapter, an IC tag configured to store an IC tag ID uniquely given to the optical connector, which is connected to a corresponding optical cable, and to receive the bus power to be driven for bus communication, and an IC tag ID obtaining unit configured to obtain the IC tag ID stored in the IC tag through the IC tag connection unit, when the optical connector is connected to the optical adapter.

An optical line terminal (OLT) channel termination (CT) comprises a receiver configured to receive an upstream message which comprises a correlation tag from an optical network unit (ONU), wherein the correlation tag represents a unique number, a processor coupled to the receiver and configured to process the upstream message, and generate a downstream message based on the upstream message, wherein the downstream message comprises the correlation tag, and a transmitter coupled to the processor and configured to transmit the downstream message to the ONU.

[Problem] To allow addition of new functions to an optical module at a low cost. [Solution] An optical transceiver 11a includes a CPU 21 configured to perform download control of a program for executing an additional function to be newly added to the optical transceiver 11a, a wireless transmitting and receiving device 22 configured to receive, in accordance with the download control, the program from a terminal device 13 that stores various programs, and a memory unit 23 configured to store the program that is received. The CPU 21 is configured to perform, by interrupting a monitoring and control signal from a transmission device 12, control to write data related to transmission and reception processing of a Tx 25a and a Rx 26a in accordance with execution of the programs stored in the memory unit 23 in a storage area at a specific address of an EEPROM 24.

To appropriately monitor a transmission device in an optical transmission system. A monitoring apparatus 1 monitors a plurality of transmission devices 2 having different specifications. The monitoring apparatus 1 includes a monitoring unit 11 that monitors whether a failure occurrence or failure recovery is present in the plurality of transmission devices 2, an analyzing unit 12 that determines whether the failure occurrence or the failure recovery continues for a predetermined period, in a case where the failure occurrence or the failure recovery is present in the plurality of transmission devices 2, a control unit 13 that identifies a cause of the failure, using a plurality of pieces of warning information received from the plurality of transmission devices 2 only in a case where the failure occurrence continues for the predetermined period, and a notifying unit 14 that notifies a higher-level monitoring apparatus of warning information corresponding to the cause of the failure.