Showing papers by "Ciena published in 2012"

Hybrid packet-optical private network systems and methods

Abstract: The present disclosure provides hybrid packet-optical private network systems and methods for a private and dedicated multi-point Ethernet Private Local Area Network (EPLAN). The network systems and methods include a Layer 1 infrastructure service with the inclusion of reserved, dedicated packet switch capacity upon which clients can build their personal, private packet networks. In the systems and methods described herein, packet networking methods are not used to partition the isolated LAN connectivity. Instead, dedicated Ethernet Private LANs (EPLs) are defined between dedicated virtual switching instances (VSIs) that are defined, as necessary, within larger packet-optical switches. Each VSI is partitioned from the remainder of its packet switch fabric as a dedicated, private resource for a specific EPLAN. A packet network is then built by the customer on top of the private EPLAN bandwidth and operated as an isolated, private network with no influence by other carrier's network resources.

Flexible transceivers

Abstract: The introduction of coherent transceivers in high capacity optical transmission systems has dramatically increased networking capabilities. We discuss how enhancing flexibility of these transceivers enables dynamic optimization of DWDM signal characteristics to extract more capacity from optical networks.

A family of Nyquist pulses for coherent optical communications

Abstract: A new family of Nyquist pulses for coherent optical single carrier systems is introduced and is shown to increase the nonlinearity tolerance of dual-polarization (DP)-QPSK and DP-16-QAM systems. Numerical investigations for a single-channel 28 Gbaud DP-16-QAM long-haul system without optical dispersion compensation indicate that the proposed pulse can increase the reach distance by 26% and 19%, for roll-off factors of 1 and 2, respectively. In multi-channel transmissions and for a roll-off factor of 1, a reach distance increase of 20% is reported. Experimental results for DP-QPSK and DP-16-QAM systems at 10 Gbaud confirm the superior nonlinearity tolerance of the proposed pulse.

Constrained continuous phase modulation and demodulation in an optical communications system

Abstract: A transmitter in an optical communications system includes a digital signal processor for processing a data signal to generate a sample stream encoding successive symbols in accordance with a constrained phase modulation scheme having a constellation of at least two symbols and a modulation phase constrained to a phase range spanning less than 4π. A digital-to-analog converter converts the sample stream into a corresponding analog drive signal. A finite range phase modulator modulates a phase of a continuous wavelength channel light in accordance with the analog drive signal, to generate a modulated channel light for transmission through the optical communications system. A receiver in the optical communications system includes an optical stage for detecting phase and amplitude of the modulated channel light and for generating a corresponding sample stream, and a digital signal processor for processing the sample stream to estimate each successive symbol of the modulated channel light.

Systems and methods for channel additions over multiple cascaded optical nodes

Abstract: A method, an optical node, and an optical network include a power controller configured to bring channels in-service in parallel over multiple cascaded optical nodes quickly, efficiently, and in a non-service affecting manner. The method, node, and network utilize multiple states of a control loop that maintains a stable response in downstream optical nodes as channels are added in parallel. Further, the power controller is configured to operate independently alleviating dependencies on other power controllers and removing the need for coordination between power controllers. The method, node, and network provide efficient turn up of dense wave division multiplexing (DWDM) services which is critical to optical layer functionality including optical layer restoration.

Colorless, directionless, and gridless optical network, node, and method

Abstract: An optical node includes an optical routing apparatus including N ports, N is an integer greater than 2, the optical routing apparatus configured to direct light that is input to each of the N ports to all of the other N ports, and a configurable optical blocking element located in line with at least one of the N ports. A method includes broadcasting a plurality of optical signals over a plurality of ports using a broadcast element, selectively receiving a desired signal from all of the plurality of optical signals at one of the plurality of ports, and blocking the plurality of signals via a blocking element in line with one of the plurality of ports thereby preventing a multiple path of the broadcast plurality of optical signals.

High speed optical communication systems and methods with flexible bandwidth adaptation

Abstract: A fiber optic system includes a transmitter configured to utilize a plurality of modulation formats and a receiver communicatively coupled to the transmitter and configured to utilize a plurality of modulation formats. The transmitter and the receiver are cooperatively configured to set a modulation format of the plurality of modulation formats based upon optical signal-to-noise ratio associated therewith. A flexible bandwidth adaptation method includes monitoring at least one aspect of an optical link at a network element, responsive to the at least one aspect, computing a new modulation scheme for the optical link, and, if a solution is found for the new modulation scheme, changing to the new modulation format.

Software defined networking systems and methods via a path computation and control element

Abstract: Software Defined Networking systems and methods are described via a Path Computation and Control Element (PCCE) that is based in part on a Path Computation Element (PCE). A common, simple interface is designed based on an existing PCE interface that allows a centralized entity (i.e., a Path Computation and Control Element or PCCE) to control the initiation of new connections or tunnels and by default to manage the state of these connections or tunnels once established. In particular, the systems and methods create an extension to the PCE architecture to allow a centralized application or applications to control the creation, rerouting and deletion of connections within a network.

Path computation systems and methods in optical networks

Abstract: A path computation method includes defining photonic constraints associated with a network, wherein the photonic constraints include wavelength capability constraints at each node in the network, wavelength availability constraints at each node in the network, and nodal connectivity constraints of each node in the network, and performing a constrained path computation in the network using Dijkstra's algorithm on a graph model of the network with the photonic constraints considered therein. An optical network includes a plurality of interconnected nodes each including wavelength capability constraints, wavelength availability constraints, and nodal connectivity constraints, and a path computation element associated with the plurality of interconnected photonic nodes, wherein the path computation element is configured to perform a constrained path computation through the plurality of interconnected nodes using Dijkstra's algorithm on a graph model with the photonic constraints considered therein.

Electro-optical switching fabric systems and methods

Abstract: An optical switch fabric, including: a first set of horizontal optical waveguides receiving a plurality of wavelengths; a plurality of wavelength-selective drop optical switches associated with the first set of horizontal optical waveguides, wherein the plurality of wavelength-selective drop optical switches are each configured to drop a selected wavelength from a horizontal optical waveguide of the first set of horizontal optical waveguides to an associated vertical optical waveguide of a plurality of vertical optical waveguides; and a plurality of controllable optical switches associated with the plurality of vertical optical waveguides, wherein the plurality of controllable optical switches are each configured to direct a selected wavelength from a vertical optical waveguide of the plurality of vertical optical waveguides to a horizontal optical waveguide of a second set of horizontal optical waveguides, and wherein the second set of horizontal optical waveguides output a plurality of wavelengths.

Raman amplifier system and method with integrated optical time domain reflectometer

Abstract: Raman amplifier systems and methods with an integrated Optical Time Domain Reflectometer (OTDR) for integrated testing functionality include an amplifier system, an OTDR and telemetry subsystem, and a method of operation. The OTDR and telemetry subsystem is configured to operate in an OTDR mode when coupled to a line in port and to operate in a telemetry mode when coupled to a line out port. The OTDR and telemetry subsystem enables on-demand fiber testing while also operating as a telemetry channel that is both a redundant optical service channel (OSC) and provides a mechanism to monitor Raman gain over time. The OTDR and telemetry subsystem minimizes cost and space by sharing major optical and electrical components between the integrated OTDR and other functions on the Raman amplifier.

Resilient interworking of shortest path bridging and Ethernet virtual private networks

Abstract: An Ethernet network, an Ethernet method, and an Ethernet node provide active-active dual-homed interworking between two Ethernet networks. The network, method, and node can include two nodes interconnected each to a Shortest Path Bridging (SPB) network and an Ethernet Virtual Private Network (E-VPN). The two nodes can utilize a same Ethernet Segment Identifier (ESI) for the E-VPN network to cause the dual-homed links to appear as a single link from an E-VPN perspective and a dummy node to advertise an extra node in the SPB network enabling two paths therein.

Photonic routing systems and methods for loop avoidance

Abstract: A photonic network includes a plurality of nodes each supporting add and drop of at least Y wavelengths, a plurality of optical links interconnecting the plurality of nodes, the plurality of optical links support up to X wavelengths and Y≦X, an optical routing protocol configured to compute a loop-free path through the plurality of nodes on the plurality of links, the loop-free path is computed for one of the X wavelengths or a group of the X wavelengths using routing constructs adapted to a photonic domain, and optical components at each of the plurality of nodes configured to selectively block at least one of the X wavelengths based on the computed loop-free path. A photonic routing method and photonic node are also disclosed.

Optical communication network path restoration

Abstract: A method and system of determining a new path through an optical network from a source node to a destination node when a link in an original path fails are disclosed. When a fault on a link is detected, adjoint weights are assigned to each operational link for each node on the original path. A connection cost is determined for each node based on the adjoint weights of the links connected to the node. A new path through the optical network is determined based at least in part on the adjoint weights and the connection costs.

Optical transport network transient management systems and methods

Abstract: An Optical Transport Network (OTN) transient management method, OTN node, and OTN network includes operating an OTN connection in a first mode in a network, the OTN connection traverses at least two nodes in the network, requesting a change in the OTN connection to a second mode which will cause a network transient, the change includes a timing change on the OTN connection affecting the at least two nodes, and performing transient management at the at least two nodes to mitigate the network transient, the transient management prevents spurious alarms due to the change between the first mode and the second mode.

Generalized service protection systems and methods

Abstract: A node includes a first port configured to be selectively blocked and unblocked; a second port configured to be selectively blocked and unblocked; a forwarder between the first port and the second port; a management channel between the first port and the second port, wherein the selective blocking and unblocking of the first port and the second port is based on the management channel; and a data channel between the first port and the second port, wherein the data channel utilizes an arbitrary service identifier. A method can include operating a ring with Ring Protection Switching comprising a forwarding mechanism and a blocking mechanism that are independent and decoupled entities therebetween, wherein the ring includes a management channel and a data channel that each utilize an arbitrary service identifier.

High capacity fiber-optic integrated transmission and switching systems

Abstract: A reconfigurable electrical add/drop multiplexing node, a network, and optoelectronic integrated circuit form a novel high capacity fiber-optic integrated transmission and switching system with a baseline target capacity in excess of 1 Tbps. The node, network, and circuit can leverage optoelectronic integration of transmission and switching components along with using the full “transparency” window of modern optical fibers from about 1270 nm to about 1670 nm for a large number of relatively low-rate wavelengths. The electrical switching fabric can be part of a Reconfigurable Electrical Add/Drop Multiplexer (READM) with similar functionality as a Reconfigurable Optical Add/Drop Multiplexer (ROADM) except in a highly integrated fashion with the transmission components. The electrical switching fabric can implement flow switching on a composite signal to provide comparable functionality to optical components in electrical circuitry such as in Complementary metal-oxide-semiconductors.

Generic multi-layer provisioning service management layer systems and methods

Abstract: Network planning/provisioning systems and methods with a Generic Multi-Layer Provisioning (GMLP) service management layer that is configured to operate on any of deployed network elements and spoofed network elements to provide abstract service modeling thereon. The GMLP layer may include a spoofing engine configured to simulate network elements and provisioning functions associated therewith. The associated abstraction of the GMLP layer enables layer 0-4 topologies and services to be modeled, planned, and provisioned.

Systems and methods for operational simplification of carrier ethernet networks

Abstract: A Carrier Ethernet method includes receiving a request to initiate an Ethernet Operations, Administration, and Maintenance (OAM) session at a local device, setting up the OAM session at the local device responsive to the request, transmitting a Protocol Data Unit (PDU) from the local device to a remote device with information related to the OAM session and the request contained therein, and receiving the PDU at the remote device and setting up the OAM session at the remote device based on the information in the PDU. The OAM session can include Ethernet Frame Loss Measurement and can be initiated only at the local device without requiring operator involvement at the remote device.

A 6-bit segmented RZ DAC architecture with up to 50-GHz sampling clock and 4 V pp differential swing

Abstract: A novel, distributed, return-to-zero (RZ) power digital-to-analog converter (DAC) architecture is presented. The circuit features 14 independent data bits - 7 for the 3 most significant bits (MSB) and 7 for the 3 least significant bits (LSB) - each running at up to 50 Gb/s. It is fabricated in a production 130-nm SiGe BiCMOS technology and operates as a large swing arbitrary waveform generator suitable for a variety of wireline, fiber optic, and instrumentation applications. The measured small signal differential gain and bandwidth of the clock path are 19 dB and 43 GHz, respectively. An output swing of 2 V pp per side is observed. Spectral measurements demonstrate multi-bit modulation at carrier frequencies as high as 50 GHz. To the best of our knowledge, this marks the highest clock frequency, highest voltage swing 6-bit DAC.

Optical transport network high order mapping systems and methods

Abstract: Optical Transport Network (OTN) High Order (HO) mapping systems and methods utilize pointer processing to map one HO signal into another similarly sized HO signal. An OTN HO mapping method and circuit include receiving a first HO signal at a first rate, asynchronously mapping the first HO signal into a second HO signal at a second rate, wherein the first rate and the second rate are substantially similar, translating a portion of overhead from the first HO signal to overhead of the second HO signal, utilizing pointers in the overhead of the second HO signal for frame alignment of the first HO signal, and transmitting the second HO signal containing the first HO signal.

Fault localization using tandem connection monitors in optical transport network

Abstract: An Optical Transport Network (OTN) fault localization method, an iterative OTN fault localization method, and an OTN network use OTN tandem connection monitors operating in a “Monitor” mode to provide fault localization. The methods and network use TCMs for fault localization that can be performed manually or automatically to isolate a fault in a multi-domain OTN network to a particular link, switching fabric, or transport function. Additionally, a roles-based assignment scheme is presented for automatically assigning TCM levels between domains and links in multi-domain OTN networks. The fault localization methods enable fault localization in an automated and non-intrusive manner.

Systems and methods for scaling performance of ethernet ring protection protocol

Abstract: The present disclosure provides systems and methods for scaling performance of Ethernet Ring Protection Protocol. Specifically, the systems and methods may apply to G.8032 and may provide protection switching control plane performance scaling benefits. In an exemplary embodiment, the present invention summarizes the per "virtual" ring control plane protocol into a single logical ring control plane protocol. Advantageously, the present invention transforms the G.8032 protocol from a per-virtual ring protocol to a per-logical ring control protocol. The mechanism/methodology that is used is to include minimal per-virtual ring instance information in to the Ring Automated Protection Switching (R-APS) (control) frames. Additionally, the present invention cleanly decouples the placement of the R-APS (control) channel block location on the ring from that of the virtual channel data blocks. Current G.8032 specifications tightly couple the location of each R-APS (control) channel block and the virtual channel block that it is managing.

Methods and systems of preserving client overhead bytes in optical transport network tunneling applications

Abstract: A method, a network, and a node each implement the transmission of Automatic Protection Switching (APS) switching coordination bytes across an OTN network. A working signal and a protection signal are received, one of which is designated as an active signal. The active signal is encapsulated in an Optical channel Data Unit (ODU) signal. APS switching coordination bytes from the working and protection signals are placed in an overhead segment of the ODU signal. The ODU signal is transmitted into and received from an Optical Transport Network (OTN) network. The working and protection signals are recreated based on the active signal encapsulated in the ODU signal and the APS switching coordination bytes in the overhead segment. The recreated working and protection signals are transmitted. In this manner, a single ODU signal may be used to transmit both the working and protection signals.

Photonic link information collection and advertisement systems and methods

Abstract: Photonic link information collection and advertisement systems and methods enable photonic nodes (e.g., optical amplifiers) to operate within a control plane system in a distributed and real-time manner. For example, the photonic nodes may not require full control plane protocol stacks at each photonic node. In particular, the systems and methods provide a distributed discovery method for photonic links without requiring full participation in the control plane at the photonic nodes. Additionally, the systems and methods include network databases with amplifier configuration information in a control plane enabled network.

Nodal contention in colorless, directionless ROADMs using traffic growth models

Abstract: We study the impact of intra-node contention in colorless, directionless ROADMs under traffic growth conditions. Our results indicate that modular add/drop banks provide blocking performance approaching that of contentionless architectures.

Optical transport network generic non-client specific protection systems and methods

Abstract: Systems and methods for generic non-client specific 1+1 protection are described supporting a uni-directional protection scheme for client interfaces on Optical Transport Network (OTN) networking equipment, regardless of the client protocol and without hardware which can participate in those client protocols. This generic non-client specific 1+1 protection can be implemented in an OTN node, an OTN switching device, or via an OTN method. Faults on client signals are escalated to, and processed at, the ODU path layer instead of the client protocol layer, providing a normalized mechanism for client signal protection.

Load balancing systems and methods of MAC learning in multi-slot architectures

Abstract: Line cards in a multi-slot network element utilize load balancing systems and methods for synchronizing learned Media Access Control (MAC) addresses therebetween. It is an objective of the load balancing systems and methods to enable high data rate scalability between line cards in a distributed system while preventing adverse effects on packet traffic. The load balancing systems and methods include inter alia MAC address updates between data path devices (e.g., network processors, application specific integrated circuits, etc.) using data frames and a hash-based time slot strategy ensuring MAC address updates are distributed over time as opposed to large scale, singular events.

Method and apparatus for configuring and validating telecom and datacom systems

Abstract: A mobile-device method and system implement validating installation of a network device, for example the installation and validation of cards within a network element. Installation data is loaded onto the mobile device and one or more cards are installed in a network element, the cards having QR codes. An image of the installation is captured and the QR codes are recognized in the captured image. The cards are identified by association with the recognized markers and the physical locations, such as slot positions, of the cards relative to the network element are determined. The installation is validated with regard to slot assignments of cards and an installation report is uploaded from the mobile device to central servers.

Frequency domain multiplex optical transmission

Abstract: A method of transmitting a data signal in an optical communications system. The method includes processing the data signal to generate an analog drive signal, wherein the processing comprises applying a first non-linear operation such that frequency components of the drive signal lay in at least two separated spectral bands. An optical carrier light is modulated using the analog drive signal.