A system supporting the daisy chaining of remote optical line terminals.

A communication apparatus including: an optical multiplexer that is configured to receive one or more optical signals for transmitting data, and generate a wavelength multiplexed signal that is an optical signal obtained by multiplexing the one or more optical signals; a first conversion signal generator that is configured to select a signal of a first wavelength from the wavelength multiplexed signal generated by the optical multiplexer, and to generate a conversion signal by converting the signal of a first wavelength being selected into a signal of a second wavelength; and a first signal selector that is configured to receive the wavelength multiplexed signal generated and the conversion signal, and to select and output at least one of a signal included in the wavelength multiplexed signal and the conversion signal, for each wavelength of a signal included in the wavelength multiplexed signal and the conversion signal.

Embodiments relate to the field of PON technologies, and provide a method, apparatus, and system. The method includes: receiving capability information that is sent by an ONU by using a first preamble; calculating a tap coefficient based on the received first preamble if the capability information indicates that the ONU has an equalization capability; sending the tap coefficient to the ONU, where the ONU updates a tap coefficient of a first equalizer in the ONU based on the received tap coefficient, and when subsequently sending upstream data, sends, by using a second preamble, the upstream data equalized by using the first equalizer, and a length of the second preamble is less than a length of the first preamble; receiving the upstream data; and equalizing the received upstream data based on the second preamble by using a second equalizer in an OLT. In this way, upstream overheads can be reduced.

An apparatus, method and computer program is described as obtaining forwarded traffic volume data and discarded traffic volume data of a point-to-multipoint communication network in each of a plurality of discrete time periods over an observation period; generating calibrated forwarded and discarded traffic volume data, wherein calibration data is dependent on a calibration level; filtering, by applying signal processing techniques, multiple instances of said calibrated forwarded and discarded traffic volume data; identifying first sample periods within said observation period; and determining impact scores for the forwarded and discarded traffic volume data for each of said one or more first sample periods.

A network design method includes calculating, from the number of wavelength filters on a transmission route of an optical signal, a bandwidth of the optical signal after narrowing by the wavelength filters, selecting, from a plurality of combinations of a multi-level modulation system and a baud rate about the optical signal set in a transmitting apparatus, one or more first combinations about which a lower-limit value of the bandwidth of the optical signal in each of the combinations is equal to or smaller than the bandwidth of the optical signal after narrowing, and selecting a second combination from the one or more first combinations based on a minimum value of an OSRN of the optical signal in the selected combinations.

An apparatus and method for optimizing dynamically the performance of an optical network, said apparatus comprising at least one learning engine adapted to update a learning model in response to network metrics of said optical network collected during operation of said optical network, wherein the updated learning model is used to generate channel rank information for network channels; and a recommendation engine adapted to change a network channel throughput, a signal path and/or a spectral location of at least one network channel based on the channel rank information generated by the learning model of said learning engine.

Disclosed herein are methods and systems for optimizing an optical signal in an optical network having a hub node configured to receive an optical signal comprising a plurality of subcarrier groups each having a signal quality and a transmission output power, including a method that may comprise: determining, a first subcarrier group of the plurality of subcarrier groups with a lowest signal quality lower than a required signal quality margin; determining, a second subcarrier group of the plurality of subcarrier groups that has a highest transmission output power margin, Determining, that the transmission output power margin of the second subcarrier group is above a level needed to increase the lowest signal quality by a required signal quality increase; and sending signals to a first leaf node and a second leaf node causing the first leaf node to swap transmission positions of the first subcarrier group and the second subcarrier group.

An apparatus includes a first communication interface configured to be communicatively coupled, via an optical line, to a network device that is disposed in an optical network using wavelength division multiplexing (WDM). The apparatus also includes a second communication interface configured to be communicatively coupled to a router via an Ethernet connection. The apparatus also includes a signal generator operatively coupled to the first communication interface and the second communication interface. The signal generator is configured to generate an Ethernet signal representing at least one attribute of the optical line between the first communication interface and the network device. The second communication interface is configured to transmit the Ethernet signal to the router.

A method for VON service with guaranteed availability may use probability density functions (PDF) of Q-factor to determine availability of physical links assigned to a virtual link in the VON. Then, a VON mapping may be performed based on the determined availabilities, among other factors.

A method, a controller, and an optical network element are configured to perform steps of monitoring one or more optical links each formed by optical transceivers which are configured to provide variable capacity via a plurality of modulation formats; based on the monitoring, causing corresponding optical transceivers for the one or more optical links to operate at a first modulation format different from a second modulation format providing excess capacity; and mapping the excess capacity to bandwidth useable by one or more services managed by the one or more of the management system, the management plane, and the control plane.