Abstract: An optical device (100) for an optical network, comprising an optical input (110), a passive optical component (112), a memory device (114) for storing information relating to the passive optical component. The optical device further comprises an optical splitter (116) configured to power split off a portion of received optical signals to form split optical signals and to output the remaining optical power of received optical signals to the passive optical component and a photodetector (118) configured to receive the split optical signals and to generate a corresponding photodetector output signal.

Abstract: In order to predict properties of a first device, data is obtained relating to properties of second devices having characteristics in common with the first device. The data comprises values of a first parameter at specific values of a second parameter. The data is organized in a first matrix with each row or column representing one value of the second parameter, and each column or row contains for one of the second devices the value of the first parameter at each of the values of the second parameter for which data is available. The first matrix is factorized into a second matrix and a third matrix. The second matrix represents a relationship between the second parameter and hidden features. The third matrix represents a relationship between the second devices and hidden features. The second matrix and/or the third matrix is used to predict at least one value of the first parameter and at least one respective specific value of the second parameter outside a predetermined range.

Abstract: There is provided an apparatus for fiber optic line continuity detection. The apparatus comprises an optical input connectable to a first optical fiber of a fiber optic line, an optical output connectable to a second optical fiber of the fiber optic line an optical interface unit configured to transmit and receive optical signals; and an optical switch having a first configuration and a second configuration. In the first configuration the optical switch is configured to pass optical signals received at the optical input to the optical interface unit and to pass optical signals received from the optical interface unit to the optical output. Whereas, in the second configuration the optical switch is configured to pass optical signals received at the optical input to the optical output.

Abstract: In one example aspect, a A method is provided of dispersion compensation for an optical link includes , the method comprising establishing communication using a first symbol rate over the optical link, determining a dispersion compensation for the optical link based on the communication at the first symbol rate, and establishing communication using a second symbol rate over the optical link using the determined dispersion compensation, wherein the second symbol rate is higher than the first symbol rate.

Abstract: Optical protection switching apparatus (10), for a single fibre bidirectional WDM optical ring, comprising: first (12) and second (14) ports for coupling to first and second adjacent portions of a single fibre bidirectional WDM optical ring; an optical splitter (16) comprising an input to receive a WDM aggregate optical signal, and first and second outputs coupled to the first and second ports; an optical switch (108) between the second output and the second port; and processing circuitry (24) to receive at least one of an indication of transmission continuity in the optical ring and an indication of transmission discontinuity in the optical ring, and to generate a switch control signal (20) comprising instructions to cause the optical switch to be open when there is transmission continuity in the optical ring and to cause the optical switch to be closed when there is transmission discontinuity in the optical ring.

Abstract: Methods and apparatus are provided for locating a fault in an optical communication link. In one aspect, a method comprises determining a fault in a first optical link, and determining a fault in a second optical link. The method then determines that a first portion of the first optical link is co-located with a second portion of the second optical link and identifies, as a result of determining that the first portion is co-located with the second portion, that the fault in the first optical link is located in the first portion and/or the fault in the second optical link is located in the second portion.

Abstract: The present disclosure relates to a method, apparatus and system for determining reliability information for a network component (240) of a telecommunications network. The disclosed method comprises: obtaining (310) a plurality of samples of an operating parameter of the network component (240) acquired over a period of time; determining (320) a value of an acceleration factor based on the plurality of samples, the acceleration factor corresponding to an effect of the operating parameter over time on the network component (240); and determining (330) the reliability information based on the determined value of the acceleration factor.

Abstract: A method of determining an end-to-end, E2E, service level for a communications network (100) by a network management entity (101). The communications network (100) comprises one or more network domain. The method comprises obtaining (201) a first set of service level data for the one or more network domain. The first set of service level data for said one or more network domain comprises a summarized set of data derived from service level data monitored by said one or more network domain. The method further comprises determining (202) the end-to-end service level based on the obtained first set of service level data from the one or more network domain.

Abstract: An optical device (100) for an optical network, comprising an optical input (110), a passive optical component (112), a memory device (114) for storing information relating to the passive optical component. The optical device further comprises an optical splitter (116) configured to power split off a portion of received optical signals to form split optical signals and to output the remaining optical power of received optical signals to the passive optical component and a photodetector (118) configured to receive the split optical signals and to generate a corresponding photodetector output signal.

Abstract: There is provided an apparatus for fiber optic line continuity detection. The apparatus comprises an optical input connectable to a first optical fiber of a fiber optic line, an optical output connectable to a second optical fiber of the fiber optic line an optical interface unit configured to transmit and receive optical signals; and an optical switch having a first configuration and a second configuration. In the first configuration the optical switch is configured to pass optical signals received at the optical input to the optical interface unit and to pass optical signals received from the optical interface unit to the optical output. Whereas, in the second configuration the optical switch is configured to pass optical signals received at the optical input to the optical output.

Abstract: A network node (400) for use as a hub node of a network that further comprises one or more remote nodes, wherein the network node (400) is coupled to at least first and second connections (410, 412) for communication with one or more remote nodes, comprises a first band filter (403) adapted to separate a first aggregated signal (404) comprising a plurality of channel signals into a plurality of band signals (4081 to 408M). The network node (400) comprises a second band filter (405) and a third band filter (407) adapted to aggregate a plurality of band signals (4081 to 408M) into a second aggregated signal (406) comprising a plurality of channel signals and a third aggregated signal (413) comprising a plurality of channel signals, respectively. A switching module (409) is adapted to switch on a per-band granularity the plurality of band signals (4081 to 408M) between the first band filter (403) and either the second band filter (405) or the third band filter (407).

Abstract: A method (100) for facilitating Optical Supervisory Channel (OSC) communications between a main site and a plurality of remote sites in an optical network is disclosed. The main and remote sites are comprised within a Radio Access Network and the main and remote sites are connected via a point to multipoint optical infrastructure. The method comprises receiving an OSC signal on an OSC from the main site (120), sequentially routing OSC signals on the OSC to each of the remote sites in a daisy chain configuration (140) and returning an OSC signal received on the OSC from a last of the remote sites in the daisy chain configuration to the main site (160), the OSC being transported over the point to multipoint optical infrastructure (170). Also disclosed are a method (500) for performing OSC communications in an optical network, a hub node (300, 400), a remote site node (600, 800) and a system (900) for communications in an optical network.

Abstract: An apparatus (20) is configured as a remote unit for communication with a main unit (10) in an optical communication network (30), wherein the main unit and remote unit are configured to detect a fault in the optical communication network. The apparatus comprises a modulation converter (22;62) configured to receive a first optical signal from the main unit on the optical communication network, wherein the first optical signal has a first modulation type. The modulation converter is configured to convert the first optical signal having the first modulation type to a second optical signal having a second modulation type. The second modulation type is different to the first modulation type. The modulation converter (22;62) is a passive device. The apparatus is configured to send the second optical signal having the second modulation type to the main unit (10) using the optical communication network (30).

Abstract: Methods and apparatus are provided for locating a fault in an optical communication link. In one aspect, a method comprises determining a fault in a first optical link, and determining a fault in a second optical link. The method then determines that a first portion of the first optical link is co-located with a second portion of the second optical link and identifies, as a result of determining that the first portion is co-located with the second portion, that the fault in the first optical link is located in the first portion and/or the fault in the second optical link is located in the second portion.

Abstract: A network node (400) for use with a single-fiber bidirectional communication link comprises a filter (300). The filter (300) comprises at least four ports. A first port (301) is configured to communicate with the single-fiber in a west direction. A second port (303) is configured to communicate with the single-fiber in an east direction. A third port (305) is configured to add/drop in the west direction. A fourth port (307) is configured to add/drop in the east direction. The network node is configured to add a first wavelength (?A) to the west direction and the east direction, and configured to drop a second wavelength (?B) from the west direction and the east direction.

Abstract: A network node (400) for use as a hub node of a network that further comprises one or more remote nodes, wherein the network node (400) is coupled to at least first and second connections (410, 412) for communication with one or more remote nodes, comprises a first band filter (403) adapted to separate a first aggregated signal (404) comprising a plurality of channel signals into a plurality of band signals (4081 to 408M). The network node (400) comprises a second band filter (405) and a third band filter (407) adapted to aggregate a plurality of band signals (4081 to 408M) into a second aggregated signal (406) comprising a plurality of channel signals and a third aggregated signal (413) comprising a plurality of channel signals, respectively. A switching module (409) is adapted to switch on a per-band granularity the plurality of band signals (4081 to 408M) between the first band filter (403) and either the second band filter (405) or the third band filter (407).

Abstract: A method (10) of bi-directional optical communication, the method comprising: generating (12) a first optical communication signal for transmission in one direction through an optical fibre, generating the first optical communication signal comprising: receiving information for transmission and generating (14) a baseband signal comprising a representation of the information; performing digital upconversion (16) of the baseband signal to form an upconverted baseband signal; performing optical modulation (18) of an optical carrier signal with the upconverted baseband signal; and restricting an optical spectrum of the first optical communication signal to a first portion of an optical channel frequency slot by performing one of digital filtering (16) in addition to digital upconversion and optical filtering (36) after optical modulation; and receiving (20) a second optical communication signal transmitted in an opposite direction through the optical fibre, the second optical communication signal having an optica

Abstract: According to embodiments of the present disclosure, apparatus is provided for protecting an optical link arranged to carry upstream optical signals and downstream optical signals. The apparatus comprises a first detector arranged to selectively detect a downstream optical signal received at a second port having a first wavelength and a second detector arranged to selectively detect a downstream optical signal received at the second port having a second wavelength different from the first wavelength. The apparatus further comprises control circuitry arranged to cause a protection switch to selectively couple a third port to the second port instead of to the first port based on the detecting by the first detector and the second detector. Also provided is a second apparatus for protecting the optical link.

Abstract: A method (10) of bi-directional optical communication, the method comprising: generating (12) a first optical communication signal for transmission in one direction through an optical fibre, generating the first optical communication signal comprising: receiving information for transmission and generating (14) a baseband signal comprising a representation of the information; performing digital upconversion (16) of the baseband signal to form an upconverted baseband signal; performing optical modulation (18) of an optical carrier signal with the upconverted baseband signal; and restricting an optical spectrum of the first optical communication signal to a first portion of an optical channel frequency slot by performing one of digital filtering (16) in addition to digital upconversion and optical filtering (36) after optical modulation; and receiving (20) a second optical communication signal transmitted in an opposite direction through the optical fibre, the second optical communication signal having an optica

Abstract: A method (100) for facilitating Optical Supervisory Channel (OSC) communications between a main site and a plurality of remote sites in an optical network is disclosed. The main and remote sites are comprised within a Radio Access Network and the main and remote sites are connected via a point to multipoint optical infrastructure. The method comprises receiving an OSC signal on an OSC from the main site (120), sequentially routing OSC signals on the OSC to each of the remote sites in a daisy chain configuration (140) and returning an OSC signal received on the OSC from a last of the remote sites in the daisy chain configuration to the main site (160), the OSC being transported over the point to multipoint optical infrastructure (170). Also disclosed are a method (500) for performing OSC communications in an optical network, a hub node (300, 400), a remote site node (600, 800) and a system (900) for communications in an optical network.