Abstract: Methods and systems are provided for flexible placement of spectral inverters in an optical network. The method includes identifying a first transmission path coupling a transmitter and a receiver. The first transmission path includes a first node for assignment of a first spectral inverter. The method further includes estimating a first optical signal-to-noise ratio (OSNR) penalty of nonlinear phase noise (NLPN) on the first transmission path with the first spectral inverter assigned to the first node, and based on the first estimated OSNR penalty of NLPN being less than an NLPN penalty threshold, assigning the first spectral inverter to the first node.

Abstract: A system includes an optical power meter operable to generate an optical power signal corresponding to the optical power of a received output signal generated by an optical IQ-modulator. The system further includes a processor operable to receive the optical power signal and determine, based on a minimization algorithm and the received optical power signal, a first bias voltage to be applied to a first sub-modulator of the optical IQ-modulator and a second bias voltage to be applied to a second sub-modulator of the optical IQ-modulator. The system may also include a peak power meter operable to generate a peak power signal corresponding to the peak power of the received output signal generated by the optical IQ-modulator, wherein the processor is further operable to determine, based on a minimization algorithm and the received peak power signal, a third bias voltage to be applied to a phase shift component of the optical IQ-modulator.

Abstract: Methods and systems are provided for optical signal transmission using span-wise spectrum management. The method includes transmitting a first optical signal at a first wavelength by a control system. The first optical signal has a first optical path distance. The method further includes determining a first guard band requirement for the first optical signal, and transmitting a second optical signal by the control system. The second optical signal has a second optical path distance. The method includes determining a second guard band requirement for the second optical signal, and placing the second optical signal spectrally adjacent to the first optical signal by selecting a second wavelength. The second wavelength is selected to satisfy the first and second guard band requirements.

Abstract: Virtual optical network (VON) provisioning using implicit encoding of mapping constraints may include evaluating mapping choices to exclude certain mapping patterns before evaluating the mapping patterns. For each virtual node in a VON request, candidate physical nodes may be assigned and evaluated for compliance with constraints associated with the VON request. The constraints may be expanded to allow for various selection criteria for the VON request. Multiple VON requests may be simultaneously evaluated to find optimal solutions for the physical network.

Abstract: A method employing resource orchestration algorithms may find a fewest number of working data centers (DCs) to guarantee K-connect survivability and a fewest number of virtual machines (VMs) among the DCs using an overlay network representing a physical optical network. The overlay network may exclude certain topological features of the physical optical network. An intra-request VM sharing method may share VMs among DCs allocated for an aggregation request. An intra-request VM sharing method may share VMs among DCs represented in the overlay network and among multiple aggregation requests.

Abstract: The present disclosure may include a method of reconfiguring a network. The method includes collecting a plurality of network demands, each of the plurality of network demands having a possible resource release by rerouting the network demand from its current path to a new path. The method further includes selecting a subset of the plurality of network demands that, if rerouted, has the highest resource release without resource contention. The method additionally includes rerouting the subset of the plurality of network demands, and, in response to rerouting the subset of the plurality of network demands, releasing resources no longer used by rerouted demands. The present disclosure may further include associated systems and apparatuses.

Abstract: A method for routing and wavelength assignment for optical network resources required for a plurality of virtual network requests includes receiving the plurality of virtual network requests. The method further includes determining a number of virtual links for each virtual network request. The method includes sorting the plurality of virtual network requests based on the number of virtual links, and selecting a virtual network request from the plurality of virtual network requests and setting a number of allowable spans. Additionally, the method includes determining whether a valid virtual node mapping exists for the virtual network request on any of a plurality of wavelengths based on the allowable spans, and based on determining that no valid virtual node mapping exists on any of the plurality of wavelengths, incrementing the number of allowable spans.

Abstract: Methods and systems are provided for flexible placement of spectral inverters in an optical network. The method includes identifying a first transmission path coupling a transmitter and a receiver. The first transmission path includes a first node for assignment of a first spectral inverter. The method further includes estimating a first optical signal-to-noise ratio (OSNR) penalty of nonlinear phase noise (NLPN) on the first transmission path with the first spectral inverter assigned to the first node, and based on the first estimated OSNR penalty of NLPN being less than an NLPN penalty threshold, assigning the first spectral inverter to the first node.

Abstract: Optical transceiver sharing methods may be based on different ROADM node architectures for shared restoration in flexible grid optical networks. A ROADM node architecture with a pool of transceivers may improve transceiver utilization for backup optical paths, compared to a conventional ROADM node architecture. Sharing of transceivers in the pool for working and backup optical paths may further improve transceiver utilization. The methods disclosed herein may be used for multiple bit rates and different modulation formats.

Abstract: Object-oriented network virtualization may involve creating and operating virtual network objects (VNO) using a software-programmed networking operating system (SPN OS). A VNO may be a complete representation of a virtual network service provided under the SPN OS. A VNO may have a unique identity and properties, along with an internal set of methods for executing functionality encapsulated by the VNO. A VNO may exhibit persistence and autonomous control to enable improved virtual network services.

Abstract: An optical network analysis tool includes a computer-readable storage medium having computer-readable instructions stored thereon. The computer-readable instructions are executable by a computing device to perform operations. The operations include generating a simulated network that models an optical network. The simulated network includes regenerator candidate sites. The operations may also include conducting an analysis of the optical network. The analysis includes introducing a multiple signals transmitted between source/destination pairs and recording a number of times each of the regenerator candidate sites are selected as a regenerator site while applying each of a set of data traffic conditions in the simulated network. The operations may also include statistically analyzing the number of times each of the regenerator candidate sites is selected to generate statistically analyzed information and presenting the statistically analyzed information.

Abstract: Methods and systems for mitigating effects of polarization dependent loss (PDL) in an optical network transmitting a multi-carrier optical signal comprising a plurality of subcarriers may involve assigning and modifying a state of polarization to each subcarrier prior to transmission. An assigned state of polarization for each subcarrier may be modified for the subcarrier in the digital domain and/or the optical domain. Various specific assignment methods may be used, including individual subcarrier assignment, subcarrier set assignment, arbitrary subcarrier group assignment, random assignment, and/or combinations thereof. The assigned states of polarization may be selected based on a resulting minimum PDL-induced peak-to-peak power variation over a sum of the subcarriers for all orientations of a principal axis of PDL.

Abstract: According to an aspect of an embodiment, a method of spectrum defragmentation in an optical network may include assigning an optical signal within an optical network to a first frequency slot that spans a first portion of an optical spectrum of the optical network. The method may also include constructing a frequency slot dependency map based on the assignation of the optical signal to the frequency slot. The method may also include reassigning, as a result of an optical signal departure event, the optical signal to a second frequency slot based on the frequency slot dependency map. The second frequency slot may span a second portion of the optical spectrum of the optical network.

Abstract: In accordance with some embodiments of the present disclosure a method for shared mesh protection in an optical transport network comprises provisioning a route for each of a plurality of working demands through the optical transport network. The method further comprises provisioning a route for backup demands corresponding to each of the plurality of working demands. The method additionally comprises packing into a single optical data unit a first backup demand corresponding to a first of the plurality of working demands and a second backup demand corresponding to a second of the plurality of working demands, wherein the first and second of the plurality of working demands share at least one common link in the optical transport network. The method also comprises unpacking the first and second backup demands from the optical data unit.

Abstract: Flexible VON provisioning may include calculating a candidate mapping pattern to satisfy a virtual optical network (VON) demand based on virtual-to-physical node mapping choices. A distance-adaptive routing and spectral slot assignment evaluation of the candidate mapping pattern may be performed. When the VON demand is satisfied by the candidate mapping pattern, the candidate mapping pattern may be added to a valid mapping patterns list. A final mapping pattern may be selected from the valid mapping patterns list, the final mapping pattern having one of a lowest slot layer and a smallest overall slot usage on the valid mapping patterns list. Then, network resources may be reserved based on the final mapping pattern selected to service the VON demand.

Abstract: An optical network for reassigning a carrier wavelength of an optical signal may include first and second optical nodes. The first optical node may be configured to transmit an optical signal along an optical path. The first optical node may also be configured to tune a carrier wavelength of the optical signal from a first wavelength to a second wavelength, according to a continuous function, to reassign the carrier wavelength of the optical signal. The second optical node may be configured to receive the optical signal and may include a feedback loop configured to adjust a wavelength of a reference optical signal to approximate the carrier wavelength of the optical signal.

Abstract: According to an aspect of an embodiment, a method of modulating supervisory data onto an optical signal includes increasing a first power level of a first polarization component of an optical signal based on supervisory data. The method further includes decreasing a second power level of a second polarization component of the optical signal based on the supervisory data. The decrease in the second power level is substantially the same as the increase in the first power level such that a total power of the optical signal is substantially constant.

Abstract: Systems and method for monitoring an optical power of a dual-polarization signal are disclosed. The systems and methods may include measuring a first parameter set associated with a supervisory signal, the supervisory signal being communicated in-band with the dual-polarization signal; calculating a second parameter set from the first parameter set; calculating an intensity value from the second parameter set, the intensity value associated with one of the polarization states of the dual-polarization signal; and estimating a signal power associated with the supervisory signal from the intensity value.

Abstract: A method for shared mesh restoration includes configuring a switch to allow sharing of a plurality of backup line cards across a plurality of node degrees associated with a reconfigurable optical add/drop multiplexer (ROADM). The switch is communicatively coupled to the ROADM. The method further includes configuring a number of backup line cards coupled to the switch. The number of backup line cards is based on determining a number of active backup lightpaths for each of a plurality of network failures associated with each of the plurality of node degrees of the ROADM, identifying which node degree and failure has the largest number of active backup lightpaths for all of the plurality of node degrees of the ROADM and for each of the plurality of network failures, and determining the number of backup line cards to configure based on the identified largest number of active backup lightpaths.

Abstract: A system and method are provided for monitoring traffic in a network comprising a plurality of links, wherein each of the plurality of links comprises a plurality of neighboring pairs of slots. The system and method may include identifying a first usage status and a second usage status, calculating a utilization entropy value based at least on the difference between the first and second usage status, iteratively calculating a set of utilization entropy values for a portion of the network, and calculating an overall utilization entropy value for the portion of the network under analysis based at least on a statistical analysis of the set of utilization entropy values.