An optical line terminal (OLT) coupled to a plurality of optical network units (ONUs) through a passive optical network (PON). The OLT includes a transceiver configured to communicate via a management channel of a communication network with a plurality of OLTs. The communication includes sending or receiving a notification, wherein the notification includes the following: a source OLT identifier associated with a source OLT sending the notification, wherein the source OLT is configured to communicate over a first channel at a first wavelength of the PON; a destination OLT identifier associated with a destination OLT receiving the notification, wherein the destination OLT is configured to communicate over a second channel at a second wavelength of the PON; and an ONU identifier associated with a first ONU associated with the notification.

Optical line terminal communication method and device with data structure

An optical line terminal (OLT) comprises a processor configured to designate an extended quiet window having a start time and a stop time. The processor may be further configured to suspend upstream transmission during the extended quiet window. The OLT further comprises a transmitter that transmits a serial number (SN) grant to an optical network unit (ONU) during the extended quiet window. Upon receiving the SN grant, the ONU may transmit a plurality of calibration request messages during the extended quiet window. Each of the calibration request messages correspond to a different attempt wavelength. The OLT may receive one of the calibration request messages at a successful attempt wavelength. The OLT transmits a calibration response message identifying the successful attempt wavelength.

Upstream Wavelength Calibration in Optical Networks

The present invention discloses a passive optical network communications method: reporting, by an optical network unit, ONU, a calibration record of the ONU, where the calibration record includes an ID of a calibrated wavelength channel; sending a first message to the ONU when the OLT determines, according to the calibration record, that a target wavelength channel ID corresponding to a target wavelength channel to which the ONU needs to switch is not in the calibration record, where the first message includes a forced wavelength switching flag; and instructing the ONU to switch to the calibrated target wavelength channel In this way, the ONU can implement wavelength switching quickly after calibrating a new wavelength channel so as to perform data communication over the calibrated new wavelength channel

Passive optical network communications method, apparatus and system

A method of Noisy Window and associated management messages to support set splitting if activating ONUs with uncalibrated transmitter, offering a power grant for unmodulated upstream transmission, measuring the average received optical power in all upstream wavelength channels and providing downstream indication of the upstream wavelength channel with abnormally high average received power.

Using noisy window for uncalibrated optical network unit activation

A multi-wavelength passive optical network (MW-PON) includes an optical distribution network (ODN), a plurality of optical line terminations (OLTs) and an optical network unit (ONU). The ODN includes a trunk fiber, one or more branching elements, and a plurality of distribution fibers. Each OLT is associated with an individual bi-directional wavelength channel using a corresponding single downstream wavelength and a corresponding single upstream wavelength, and supporting a specific downstream line rate and one or more distinct upstream line rates. The ONU is communicatively coupled to a respective distribution fiber, being tunable over a specific range of downstream wavelengths and a specific range of upstream wavelengths, and supporting a specific downstream line rate and a specific upstream line rate. The OLT is configured to assemble a broadcast management message conveying information about bi-directional wavelength channels in said MW-PON system and transmit said message downstream over the associated bi-directional wavelength channel.

Channel map for optical network unit activation and rogue behavior prevention

The invention presents the channel management technology in a Time and Wavelength Division Multiplexing-Passive Optical network (TWDM-PON). According to an exemplary embodiment, the channel management technology is a wavelength management method for an Optical Network Unit (ONU) having a tunable receiver in the TWDM-PON in which a service is provided through multiple channels, the wavelength management method including: setting a wavelength of the tunable receiver as a first channel to receive a physical synchronization signal from an Optical Line Terminal (OLT); extracting either or both service utilization information and service operator information from the physical synchronization signal; and based on either or both of the service utilization information and the service operator information, determining whether to perform follow-up procedures for activation via the first channel or whether to change the wavelength of the tunable receiver into a second channel.

Channel management method in time and wavelength division multiplexing-passive optical network (twdm-pon)

A method of tuning a wavelength of a tunable ONU in a TWDM-PON is provided. The method includes transmitting a wavelength change request message from a source OLT to request the ONU to change a wavelength thereof from a first wavelength to a second wavelength and in response to the wavelength change request message, transmitting a wavelength change response message from the ONU to the source OLT to indicate whether or not the ONU can change a wavelength thereof. The wavelength change request message is ID information for specifying an ONU that is requested to change a wavelength thereof, and the message may comprise one of the following: system ONU ID, channel ONU ID, and individual ONU ID.

Method of tuning wavelength of tunable optical network unit (onu) in time and wavelength division multiplexing-passive optical network (twdm-pon)

A method of tuning a wavelength in a TWDM-PON which has a plurality of operable channels is provided. First, a second channel is added as an operating channel of the TWDM-PON in which at least a first channel is working, and then an OLT that is providing a service to an ONU through the first channel requests the ONU to tune to the second channel. In response to receiving the request, the ONU determines whether a downstream wavelength of the second channel has been recorded thereon. According to the determination result, the ONU sends to the OLT an ACK message that indicates that the ONU is able to perform wavelength tuning and then commences wavelength tuning to the second channel, or the ONU sends to the OLT a NACK message that indicates that the ONU is unable to perform wavelength tuning.

Method of tuning wavelength in time and wavelength division multiplexing-passive optical network (TWDM-PON)

An optical access network plays a critical role in accommodating explosive new services such as augmented reality (AR), virtual reality (VR), machine-to-machine, and human-to-machine interaction applications. Continuous expansion of capacity as well as low latency in the optical access network are very important issues to avoid loss of connectivity for 5G and Tactile Internet. A time-division multiplexing passive optical network (TDM-PON) is an attractive solution to provide optical connectivity to end users in residential, business, and mobile applications since multiple remote nodes with simple optical power splitters give us easy-to-use optical connection anywhere in an optical distributed network. This article reviews TDM-PON-based optical access technologies for bandwidth-intensive as well as low-latency services, and introduces a recent feasibility demonstration of a Tactile Internet testbed. Technical challenges faced by TDM-PON for future networks in terms of capacity, latency, and virtual-izationlslicing are also discussed.

TDM-PON-Based Optical Access Network for Tactile Internet, 5G, and Beyond

A method of determining a physical layer wavelength of a tunable optical network unit (ONU) in a time wavelength division multiplexing-passive optical network (TWDM-PON) is provided. First, a receiving wavelength of a tunable receiver is tuned to a downstream wavelength of one of a plurality of operable channels in a TWDM-PON system. Then, it is checked whether the tunable receiver maintains a state of loss of signal (LOS) for a predetermined period of time or the state of LOS is cleared. In response to a determination that the state of LOS is cleared, the ONU performs subsequent link establishment procedures in the channel, and in response to a determination that the state of LOS is maintained, the receiving wavelength of the tunable receiver is changed to a downstream wavelength of another channel.

Method of determining physical layer wavelength of tunable optical network unit (onu) in time and wavelength division multiplexed passive optical network (twdm-pon)

Kwang Ok Kim

Papers

Channel management method in time and wavelength division multiplexing-passive optical network (twdm-pon)

Method of tuning wavelength of tunable optical network unit (onu) in time and wavelength division multiplexing-passive optical network (twdm-pon)

Method of tuning wavelength in time and wavelength division multiplexing-passive optical network (TWDM-PON)

TDM-PON-Based Optical Access Network for Tactile Internet, 5G, and Beyond

Method of determining physical layer wavelength of tunable optical network unit (onu) in time and wavelength division multiplexed passive optical network (twdm-pon)