In a case where a wavelength to be assigned to a subscriber-side device, to which a downstream wavelength has been assigned, is to be changed from the currently used (Source) downstream wavelength to a different changeover target (Target) downstream wavelength, a downstream wavelength changeover instruction message that indicates the change target wavelength is generated. In a case where a wavelength to be assigned to the subscriber-side device, to which an upstream wavelength has been assigned, is to be changed from the currently used (Source) upstream wavelength to a different changeover target (Target) upstream wavelength, an upstream wavelength changeover instruction message that indicates the change target wavelength is generated. The downstream wavelength changeover instruction message and the upstream wavelength changeover instruction message are respectively independently generated, and only the wavelength for which the wavelength changeover instruction message was generated is changed.

A system and method for performing an in-service optical time domain reflectometry test, an in-service insertion loss test, and an in-service optical frequency domain reflectometry test using a same wavelength as the network communications for point-to-point or point-to-multipoint optical fiber networks while maintaining continuity of network communications are disclosed.

A station-side device of the present invention includes: a wavelength change instruction unit that issues, to a subscriber-side device, a wavelength change instruction to change a transfer-source wavelength assigned to the subscriber-side device to a transfer-target wavelength different from the transfer-source wavelength; a transfer-source port that transmits and receives an optical signal of the transfer-source wavelength; a transfer-target port that transmits and receives an optical signal of the transfer-target wavelength; a transfer-source port monitoring unit that detects a connection between the transfer-source port and the subscriber-side device; a transfer-target port monitoring unit that detects a connection between the transfer-target port and the subscriber-side device; a transfer-source timer that counts, at the transfer-source port, an elapsed time from a predetermined starting time in response to the wavelength change instruction, and ends the counting of the elapsed time in a case where change to the transfer-target wavelength is complete; and a transfer-target timer that counts, at the transfer-target port, an elapsed time from a predetermined time in response to the wavelength change instruction, and ends the counting of the elapsed time in a case where the change to the transfer-target wavelength is complete.

A system and method for performing an in-service optical time domain reflectometry test, an in-service insertion loss test, and an in-service optical frequency domain reflectometry test using a same wavelength as the network communications for point-to-point or point-to-multipoint optical fiber networks while maintaining continuity of network communications are disclosed.

A method for detecting an optical network unit (ONU) in a passive optical network (PON), an ONU, a PON and an optical line terminal (OLT) are disclosed. In an embodiment the method include detecting an ONU identity code in an open uplink empty window or an empty timeslot, wherein the ONU identity code is a specific code stream sequence of the ONU that identifies a single ONU of the plurality of ONUs included in the PON system during the open uplink empty window or the empty timeslot and determining that the single ONU corresponding to the ONU identity code is a rogue ONU according to the ONU identity code.

Digital information can be carried on the fiber leg of an access network using binary modulation. Binary modulated data received at an O/E node can then be modulated onto an analog waveform using quadrature amplitude modulation or some other technique for modulating an analog waveform and transmitted over, for example, the coaxial leg of the network. The O/E node may also receive an analog signal, over the coaxial leg, modulated to carry upstream data from subscriber devices. The O/E node may demodulate the upstream signal to recover the upstream data and forward that upstream data over the fiber leg using a binary modulated optical signal.

A coherent passive optical network includes a downstream transceiver and first and second upstream transceivers in communication with an optical transport medium. The downstream transceiver includes a downstream processor for mapping a downstream data stream to a plurality of sub-bands, and a downstream transmitter for transmitting a downstream optical signal modulated with the plurality of sub-bands. The first upstream transceiver includes a first local oscillator (LO) for tuning a first LO center frequency to a first sub-band of the plurality of sub-bands, and a first downstream receiver for coherently detecting the downstream optical signal within the first sub-band. The second upstream transceiver includes a second downstream receiver configured for coherently detecting the downstream optical signal within a second sub-band of the plurality of sub-bands. The downstream processor dynamically allocates the first and second sub-bands to the first and second transceivers in the time and frequency domains.

Digital information can be carried on the fiber leg of an access network using binary modulation. Binary modulated data received at an O/E node can then be modulated onto an analog waveform using quadrature amplitude modulation or some other technique for modulating an analog waveform and transmitted over, for example, the coaxial leg of the network. The O/E node may also receive an analog signal, over the coaxial leg, modulated to carry upstream data from subscriber devices. The O/E node may demodulate the upstream signal to recover the upstream data and forward that upstream data over the fiber leg using a binary modulated optical signal.

A system and method for performing an in-service optical time domain reflectometry test, an in-service insertion loss test, and an in-service optical frequency domain reflectometry test using a same wavelength as the network communications for point-to-point or point-to-multipoint optical fiber networks while maintaining continuity of network communications are disclosed.

In one embodiment, a method for passive optical network (PON) communication includes broadcasting, by an optical line terminal (OLT), a first message including a first start time of a first quiet window and a first allocation identification number (Alloc-ID), where the first Alloc-ID indicates a first supported upstream line rate associated with the first quiet window. The method also includes receiving, by the OLT from a first optical network unit (ONU) during the first quiet window, a first serial number response, wherein a first transmitting upstream line rate of the first ONU is equal to the first supported upstream line rate.