Abstract: A method and apparatus for the efficient dynamic allocation of additional bandwidth in an optical virtual private network (OVPN) are described herein. A software defined network (SDN) controller may receive a request from an end-user of an OVPN for active bandwidth. Then, the SDN controller may determine whether the OVPN requires additional bandwidth to satisfy the request. As of the request, the additional bandwidth may be pre-deployed, but not yet activated for use. In an example, a path computation element (PCE) of the SDN controller may make this determination. Further, the SDN controller, on a condition that additional bandwidth is required, may determine whether additional bandwidth may be activated based on a policy of the end-user. As a result, the SDN controller, on a condition that additional bandwidth may be activated, may transmit an activation message to one or more line cards of the OVPN to activate the additional bandwidth.

Abstract: Consistent with the present disclosure, an apparatus for producing a control signal for a laser source is provided, comprising an etalon configured to receive light from the laser source and control circuitry that provides the control signal, wherein the control signal is indicative of a comparison of (a) a difference between a forward transmission signal of the etalon and a backward reflection signal of the etalon and (b) the light received by the etalon from the laser source. Alternatively, the control signal is indicative of a comparison of (a) a difference between a forward transmission signal of the etalon and a backward reflection signal of the etalon and (b) a combination of the forward transmission signal of the etalon and the backward reflection signal of the etalon.

Abstract: Consistent with the present disclosure, one or more spare Widely Tunable Lasers (WTLs) are integrated on a PIC. In the event that a channel, including, for example, a laser, a modulator and a semiconductor optical amplifier in a transmitter or Tx PIC, or a laser, optical hybrid, and photodiodes, for example, in a receiver PIC (Rx PIC), includes one or more defective devices, a spare channel is selected that includes a widely tunable laser (WTL) which may be tuned to the wavelength associated with any of the channels on the PIC. Accordingly, the spare channel replaces the defective channel or the lowest performing channel and outputs modulated optical signals at the wavelength associated with the defective channel. Thus, even though a defective channel may be present, a die consistent with the present disclosure may still output or receive the desired channels because the spare channel replaces the defective channel.

Abstract: Consistent with the present disclosure, one or more spare Widely Tunable Lasers (WTLs) are integrated on a PIC. In the event that a channel, including, for example, a laser, a modulator and a semiconductor optical amplifier in a transmitter or Tx PIC, or a laser, optical hybrid, and photodiodes, for example, in a receiver PIC (Rx PIC), includes one or more defective devices, a spare channel is selected that includes a widely tunable laser (WTL) which may be tuned to the wavelength associated with any of the channels on the PIC. Accordingly, the spare channel replaces the defective channel or the lowest performing channel and outputs modulated optical signals at the wavelength associated with the defective channel. Thus, even though a defective channel may be present, a die consistent with the present disclosure may still output or receive the desired channels because the spare channel replaces the defective channel.

Abstract: Consistent with the present disclosure, one or more spare Widely Tunable Lasers (WTLs) are integrated on a PIC. In the event that a channel, including, for example, a laser, a modulator and a semiconductor optical amplifier in a transmitter or Tx PIC, or a laser, optical hybrid, and photodiodes, for example, in a receiver PIC (Rx PIC), includes one or more defective devices, a spare channel is selected that includes a widely tunable laser (WTL) which may be tuned to the wavelength associated with any of the channels on the PIC. Accordingly, the spare channel replaces the defective channel or the lowest performing channel and outputs modulated optical signals at the wavelength associated with the defective channel. Thus, even though a defective channel may be present, a die consistent with the present disclosure may still output or receive the desired channels because the spare channel replaces the defective channel.

Abstract: A versioning system for network state of a network includes: a server, configured to execute a versioning controller, the versioning controller being configured to communicate with a plurality of data plane devices of the network and store a plurality of network states in a local non-transitory memory corresponding to the server, wherein the plurality of network states stored in the local non-transitory memory include a current authoritative network state and a plurality of previous network states each corresponding to a modification of a flow within the network; and the plurality of data plane devices, configured to notify the server of flow modifications made by respective data plane devices and to receive the current authoritative network state from the server.

Abstract: A system and method are disclosed to characterize and correct for the effects of IQ skew and insertion loss in a coherent optical transmitter. The coherent optical transmitter receives a digital data signal including in-phase (I) and quadrature (Q) components and generates corresponding first and second dither signals. The first dither signal may be combined with the I component and the second dither signal may be combined with the Q component to generate I and Q combined signals, which may be converted into I and Q analog waveforms. An optical signal may be generated corresponding to the I and Q analog waveforms for transmission over an optical fiber. The IQ skew and/or insertion loss for the coherent optical transmitter may then be calculated based on the optical signal using the disclosed dither tone processing techniques in order to correct IQ skew and/or insertion loss impairment.

Abstract: A method and system for flow tracing for use in a packet-optical network is disclosed herein. A device in the packet-optical network may receive a packet including a header and payload. The device may read intent information from the header, and translate the intent information to generate a device-specific action in an optical layer to provide one or more globally unique identifiers (IDs) associated with the device. The device may execute the device-specific action in the optical layer to generate a response including the globally unique IDs corresponding to the intent, where the response forms part of the flow trace. The device may associate the response with the intent, and encode the response for downstream data forwarding. The device may further add multi-layer proof-of-transit (POT) information to the response that may be used to securely verify the path indicated in the SmartFlow flow trace.

Abstract: A method, comprises measuring, by circuitry of a computer system, a first bandwidth of data traffic of a transport path over a time period, the transport path passing through a plurality of nodes and conforming to a protocol using a number of time slots to allocate a second bandwidth to the transport path. The method further includes passing a signal, from the computer system to at least one of the nodes of the transport path, the signal including at least one instruction that when executed by circuitry of the at least one node causes a change to the number of time slots allocated to the transport path.

Abstract: Systems, methods, and devices for determining a property of, or isolating a fault in, a transport segment. A packet portion test packet can be transmitted over a packet portion of a transport segment. Packet portion results can be received in response to the packet portion test packet. A transport portion test packet can be transmitted over a transport portion of the transport segment. Transport portion results can be received in response to the transport portion test packet. The packet portion results and the transport portion results can be correlated to generate correlated test results. The correlated test results can be processed to determine the property of, or isolate the fault in, the transport segment.

Abstract: Embodiments include methods and apparatuses for providing at least one signaling indication of a super-channel by a power controller in a Wavelength Division Multiplexing (WDM) system. The power controller may receive a service provisioning and a lock state from a network management entity. The power controller may receive, from an optical fabric unit, a fabric state that indicates whether a pass-band of the super-channel is provisioned. The power controller may receive the power level of the super-channel from a power monitoring unit. Based on the power level and attenuation level of the super-channel, the power controller may determine a ramp state that indicates whether the power level reached to a predetermined power. The power controller may determine an alarm state based on the power level. The power controller may determine the signaling indication based on the service provisioning, lock, fabric, ramp, and alarm states.

Abstract: A transmitter is provided that transmits data in either a “quasi-DP-BPSK” (“QDP”) mode or in a DP-QPSK mode. In the QDP mode, data bits are transmitted as changes in phase between first and second phase states along a first axis or as changes in phase between third and fourth phase states along a second axis in the IQ plane. A sequence bit identifies which axis carries the data bit. The sequence bit is one of a series of sequence bits that may be generated by a pseudo-random number generator. The series of sequence bits can be relatively long to permit sufficiently random changes in the axis that carries the data. Thus, unlike conventional BPSK, in which data is transmitted between phase states along a single axis, the present disclosure provides an apparatus and related method for randomly selecting one of two axes, for example, for each transmitted bit.

Abstract: Systems, methods, and devices for adding an alien or native wavelength optical signal to a fiber optic line. A portion of a spectrum of the fiber optic line corresponding to the optical signal is blocked with a wavelength selective switch (WSS). The portion of the spectrum is gradually unblocked until a power of the optical signal measured after the WSS is equal to a predetermined level. If the power and characteristics of the optical signal after the WSS satisfy one or more criteria, the portion of the spectrum is further unblocked until the power of the optical signal measured at the output is equal to an operational level.

Abstract: A method of many-to-one auto-discovery between modules includes: a source (sender) module sends the same source-ID on all its connected ports (many). The module may not know on which port the ID is sent. A sink (receiver) module is capable of receiving IDs on its port (one). The sink port identifies the association-ID (AID) of one end of the association (between sender and receiver). The association may be established based on each module discovering the sink AID of the sender in both directions (bi-directional). Both directions may be required for the source signal to get received on a respective sink. The source signal may be sent asynchronously in each direction.

Abstract: Consistent with the present disclosure, an optical communication system is provided in which data is carried over optical signals including subcarriers. The subcarriers may be modulated with the standard modulation formats noted above, but the modulation formats are selectively assigned to the subcarriers, such that some subcarriers are modulated with different standard modulation formats than others. As used herein, a “standard modulation format” is one of BPSK, and n-QAM, where n is an integer greater than one. Such n-QAM modulation formats include of 3-QAM, 4-QAM (QPSK), 8-QAM, 16-QAM, 64-QAM, 128-QAM, and 256-QAM. By selecting the number of subcarriers and the types of modulation formats employed, an optical signal with an effective SE that is between that of the standard modulation formats can be generated for transmission over a distances that more closely matches the link distance.

Abstract: Apparatus and methods may provide improved equalizer performance, e.g., for optical-fiber-based communication systems. A least-mean-square (LMS) equalizer may include a decision feedback path containing feedback carrier recovery (FBCR), which may have low latency, and which may thus enable high-speed tap updating in the equalizer. Feed-forward carrier recovery (FFCR) may be applied, in parallel with the FBCR, to provide equalizer output by compensating, e.g., for phase noise, with improved carrier recovery/compensation, versus using FBCR to generate the output.

Abstract: Methods and systems for determining data transport paths through data transport subnetworks include a method for receiving, by circuitry of a computer system, a service request message from an edge node coupled with the circuitry of the computer system, the service request message including information indicative of: a first unique identifier of an ingress port of a first core node, the first core node being within a transport subnetwork; a second unique identifier of an egress port of a second core node within the transport subnetwork; and a requested transport path bandwidth. The method further comprises determining, by the circuitry of the computer system, a transport path through the transport subnetwork between the first core node and the second core node based on the service request message; and forming the transport path between the ingress port of the first core node and the egress port of the second core node.

Abstract: A method and system for packet-optical in-band telemetry (POINT) that may be used in a packet-optical network is disclosed herein. An intermediate POINT device may receive a packet including at least a header and a payload at a packet layer. The POINT device may read intent information from the header, and the intent information may indicate a type of telemetry data to be collected. The POINT device may translate the intent information from the packet layer to generate a device-specific action in an optical layer to the type of telemetry data indicated by the intent. The POINT device may execute the device-specific action in the optical layer to generate a response corresponding to the intent, associate the response with the intent, and encode the response in the packet layer for downstream data forwarding.

Abstract: Methods and apparatuses for data transformation are disclosed. An exemplary apparatus includes a first memory, a second memory, a cross-bar switch communicatively coupled between the first memory and the second memory, and a lookup table that specifies one or more memory addresses of the first memory to read out to the cross-bar switch, one or more memory addresses of the second memory to which to write data from the cross-bar switch, and a configuration of the cross-bar switch. An exemplary method includes determining, based on a lookup table, one or more memory addresses of a first memory to read out to a cross-bar switch, determining, based on the lookup table, one or more memory addresses of a second memory to which to write data from the cross-bar switch, and determining, based on the lookup table, a configuration of the cross-bar switch.

Abstract: A method and node are disclosed. In the method, circuitry of a first node generates a link state advertising message including bandwidth information indicative of unreserved number of optical channel data unit containers for a plurality of different types of signals supported by an interface of the first node. The link state advertising message is transmitted from the first node to a plurality of second nodes within a mesh network.