Abstract: A method for calculating configuration of an optical transmission network includes: acquiring an initial value of an input power of an optical cable; based on the initial value, obtaining an output power of each channel at an end of a section of the optical cable according to a loss of the optical cable; taking the output power of each channel at the end of the section as a boundary condition to calculate the input power of each channel at the section based on an amount of optical power transferred from a high-frequency channel to a low-frequency channel due to an SRS effect; and calculating a first parameter value of an optical amplifier of the section using the input power of each channel at the section and the output power of each channel at the end of a preceding section of the section.

Abstract: An optical transmission system is provided. The optical transmission system includes a first board card including a multiplexer/demultiplexer, and an optical amplifier. The multiplexer/demultiplexer is configured to receive a plurality of first split optical signals and combine the received plurality of first split optical signals into a first combined optical signal, and the optical amplifier is configured to amplify power of the first combined optical signal.

Abstract: One embodiment described herein provides a system for distributed fiber sensing. The system can include a plurality of network elements (NEs) in an optical transport network (OTN) and a control-and-management module coupled to the NEs. A respective network element (NE) can include a first wavelength coupler configured to separate an optical supervisory channel (OSC) signal from a data-carrying signal received from a fiber span, a polarization-measurement unit configured to perform a polarization measurement on the OSC signal, and a transmitter configured to transmit an outcome of the polarization measurement to the control-and-management module, thereby facilitating distributed fiber sensing based on the outcome of the polarization measurement.

Abstract: One embodiment described herein provides a co-packaged optics (CPO) switch assembly. The CPO switch assembly includes a switch integrated circuit (IC) chip and a number of optical modules coupled to the switch IC chip. The switch IC chip and the optical modules are co-packaged within a same physical enclosure. The switch IC chip includes a switch logic and a digital signal processing (DSP) unit, and a respective optical module comprises: a photonic integrated chip (PIC), a first amplifier module, and a second amplifier module.

Abstract: One embodiment described herein provides a co-packaged optics (CPO) switch assembly. The CPO switch assembly includes a switch integrated circuit (IC) chip and a number of optical modules coupled to the switch IC chip. The switch IC chip and the optical modules are co-packaged within a same physical enclosure. The switch IC chip includes a switch logic and a digital signal processing (DSP) unit, and a respective optical module comprises: a photonic integrated chip (PIC), a first amplifier module, and a second amplifier module.

Abstract: One embodiment described herein provides a network switch. The network switch can include a co-packaged optics (CPO) assembly comprising a switch integrated circuit (IC) module and a number of optical modules coupled to the switch IC module, a remote laser source external to the CPO assembly configured to provide continuous wave (CW) light to the optical modules, a number of wavelength multiplexer/demultiplexer arrays external to the CPO assembly, and a plurality of connector arrays comprising a first number of far reach (FR) connector arrays and a second number of datacenter reach (DR) connector arrays.

Abstract: One embodiment described herein provides a system for distributed fiber sensing. The system can include a plurality of network elements (NEs) in an optical transport network (OTN) and a control-and-management module coupled to the NEs. A respective network element (NE) can include a first wavelength coupler configured to separate an optical supervisory channel (OSC) signal from a data-carrying signal received from a fiber span, a polarization-measurement unit configured to perform a polarization measurement on the OSC signal, and a transmitter configured to transmit an outcome of the polarization measurement to the control-and-management module, thereby facilitating distributed fiber sensing based on the outcome of the polarization measurement.

Abstract: One embodiment can provide an optical transceiver based on silicon photonics. The optical transceiver can include an optical transmitter and an optical receiver. The optical transmitter or the optical receiver can include one or more semiconductor optical amplifiers (SOAs) configured to amplify optical signals to be transmitted by the optical transmitter or optical signals received by the optical receiver, respectively, thereby facilitating the optical transceiver to meet an optical power budget requirement of a high-speed optical link.

Abstract: Embodiments described herein provide an apparatus for facilitating a double-density small form-factor pluggable (SFP-DD) module. The apparatus includes a set of control connector pins for exchanging control signals. The apparatus also includes a first set of communication connector pins for establishing a first communication channel and a second set of communication connector pins for establishing a second communication channel. The set of control connector pins and the first set of communication connector pins correspond to connector pins of an SFP module, and the second set of communication connector pins extends the SFP module. The size of the SFP-DD module corresponds to the size of the SFP module.

Abstract: One embodiment of the present invention provides an optical link coupling two nodes in an optical transport network. The optical link includes a fiber span, which includes a first optical fiber, a second optical fiber, and a splitter. The input of the splitter is coupled to an input of the fiber span, and first and second outputs of the splitter are coupled, respectively, to the first and second optical fibers. The optical link further includes a first amplifier coupled to the first optical fiber, a second amplifier coupled to the second optical fiber, and an optical switch. Two inputs of the optical switch are coupled to outputs of the first and second amplifiers, respectively; and an output of the optical switch is coupled to an input of a third amplifier.

Abstract: We disclose an optical transport system configured to reduce nonlinear signal distortions using an electronic phase rotation, the phase value of which is determined using pre-filtering, e.g., via a low-pass filter, of the digital samples representing an optical communication signal prior to applying a squaring operation to the digital samples. In some embodiments, the phase value used in the electronic phase rotation can be determined using double filtering of the digital samples that, in addition to the pre-filtering, employs post-filtering, e.g., via another low-pass filter, of the digital samples generated by the squaring operation. The electronic phase rotation can be implemented as part of a backward-propagation algorithm that, in addition to reducing the nonlinear signal distortions, provides at least partial dispersion compensation. In various embodiments, the corresponding backward-propagation module can be incorporated into the transmitter's digital signal processor (DSP) or the receiver's DSP.

Abstract: One embodiment of the present invention provides an optical transceiver. The transceiver can include a transmitter and a receiver. Each of the transmitter and receiver can include a plurality of space-division multiplexing (SDM) channels configured to transmit or receive spatially separated optical signals. A respective SDM channel can include a plurality of wavelength channels and an optical wavelength multiplexer or demultiplexer configured to multiplex or demultiplex optical signals to or from the plurality of wavelength channels.

Abstract: One embodiment described herein provides a system and method for distributing quantum keys between first and second applications running on first and second client devices, respectively. During operation, a first application running on the first client device can transmit a first key request to a first quantum-key-management (QKM) module managing a first set of quantum keys, and transmit a notification to the second application running on the second client device, the notification prompting the second application to transmit a second key request to a second QKM module managing a second set of quantum keys. The first application can receive, from the first QKM module, a first quantum key based on the first key request, in response to the first QKM module determining that the second application receives a second quantum key based on the second key request.

Abstract: A method and device for detecting shared risk link groups is disclosed. The method comprises injecting a probe beam, respectively, into a first test link and a second test link. The method further includes recording, respectively, a first curve of a time-varying first power corresponding to the first backlight and a second curve of a time-varying second power corresponding to the second backlight; calculating a resemblance value for the first curve and the second curve; and judging, based on the resemblance value, whether the first test link and the second test link are located in the same shared risk link group. The method and device for detecting shared risk link groups provided by embodiments of the present invention detect by testing a power characteristic of backlight of a probe beam in test links and, based on that one-dimensional power characteristic, judge whether the test links are in the same shared risk link group, which are simpler in application than those in the prior art.

Abstract: Embodiments described herein provide an apparatus for facilitating a double-density small form-factor pluggable (SFP-DD) module. The apparatus includes a set of control connector pins for exchanging control signals. The apparatus also includes a first set of communication connector pins for establishing a first communication channel and a second set of communication connector pins for establishing a second communication channel. The set of control connector pins and the first set of communication connector pins correspond to connector pins of an SFP module, and the second set of communication connector pins extends the SFP module. The size of the SFP-DD module corresponds to the size of the SFP module.

Abstract: One embodiment of the present invention provides an optical link coupling two nodes in an optical transport network. The optical link includes a fiber span, which includes a first optical fiber, a second optical fiber, and a splitter. The input of the splitter is coupled to an input of the fiber span, and first and second outputs of the splitter are coupled, respectively, to the first and second optical fibers. The optical link further includes a first amplifier coupled to the first optical fiber, a second amplifier coupled to the second optical fiber, and an optical switch. Two inputs of the optical switch are coupled to outputs of the first and second amplifiers, respectively; and an output of the optical switch is coupled to an input of a third amplifier.

Abstract: We disclose an optical transport system configured to reduce nonlinear signal distortions using an electronic phase rotation, the phase value of which is determined using pre-filtering, e.g., via a low-pass filter, of the digital samples representing an optical communication signal prior to applying a squaring operation to the digital samples. In some embodiments, the phase value used in the electronic phase rotation can be determined using double filtering of the digital samples that, in addition to the pre-filtering, employs post-filtering, e.g., via another low-pass filter, of the digital samples generated by the squaring operation. The electronic phase rotation can be implemented as part of a backward-propagation algorithm that, in addition to reducing the nonlinear signal distortions, provides at least partial dispersion compensation. In various embodiments, the corresponding backward-propagation module can be incorporated into the transmitter's digital signal processor (DSP) or the receiver's DSP.

Abstract: An apparatus includes an optical transmitter configured to provide an optical signal amplitude-modulated among M different levels. A constellation control module is configured to provide a drive signal to control the optical signal. A feedback module is configured to receive a measure of spacing between amplitude peaks of a symbol constellation of the optical signal. The feedback module is further configured to regulate the constellation control module to adjust the optical signal in response to the measure of spacing.

Abstract: We disclose an optical transport system configured to transport data using a PDM-modulation format, in which each of two orthogonal polarizations is independently amplitude-modulated, and the relative phase between the carrier waves of the two polarizations may also be modulated. This modulation format enables the optical receiver to perform direct optical detection using a Stokes-vector detector to fully recover the encoded data.

Abstract: We disclose an optical receiver having a configurable clock-recovery module, an operative configuration of which is selectable based on a bandwidth of the optical input signal. In an example embodiment, the clock-recovery module adopts a first configuration for non-Nyquist optical input signals, and adopts a different second configuration for Nyquist and faster-than-Nyquist optical input signals. The configurability of the clock-recovery module may advantageously prevent the clock-recovery algorithm from breaking down, e.g., due to variability of the bandwidth of the optical input signal caused by the variability of the routes that optical signals may take in the corresponding optical-transport network before arriving at the optical receiver.