Patent application number | Description | Published |
20090052892 | Communication Network with Co-Routed Multi-Channel Traffic - Embodiments of the present invention route a wavelength division multiplexed signal across multiple communication paths using skew characteristics of at least some of the communication paths. The network is a wavelength division multiplexed optical transport network. The plurality of communication paths involves different signal and path attributes such as a plurality of carrier wavelengths, optical carrier groups, physical communication paths (different nodes, different fibers along a same path, or any combination of the foregoing), or any other differentiating factors between two paths. | 02-26-2009 |
20090161247 | Channel Skew Identification and Notification - Embodiments of the present invention analyze a plurality of parallel channels and identify specific channel(s) that have skew outside of an acceptable skew error margin. In certain embodiments, this skew is identified by determining the timing misalignment between a channel under test and a deskew channel. Other channels within the plurality of channels are masked by transmitting a repeating masked bit pattern. This timing misalignment may be measured by comparing a segment within the channel under test to a corresponding segment within the deskew channel and identifying a time differential between the two segments. | 06-25-2009 |
20090245793 | Mapping a Client Signal into Transport Frames - Embodiments of the present invention provide a systems, devices, and methods in which a client signal is divided into a plurality of channels, mapped within transport frames, and combined into a WDM transport signal. These embodiments include intra-nodal redundancy that protects against failure events within the transport transmitter. In particular, redundancy is provided within a network transport transmitter such that redundant paths are available so that electrical channels may be routed around a malfunctioning component within the transmitter. | 10-01-2009 |
20090324220 | COMMUNICATION NETWORK WITH NODE BYPASSED CO-ROUTED MULTI-CHANNEL TRAFFIC - Embodiments of the present invention route a wavelength division multiplexed signal across multiple communication paths using skew characteristics of at least some of the communication paths. The network is a wavelength division multiplexed optical transport network. The plurality of communication paths involves different signal and path attributes such as a plurality of carrier wavelengths, optical carrier groups, physical communication paths (different nodes, different fibers along a same path, or any combination of the foregoing), or any other differentiating factors between two paths. | 12-31-2009 |
20100014861 | DUAL ASYNCHRONOUS MAPPING OF CLIENT SIGNALS OF ARBITRARY RATE - A network may include an ingress node that is configured to receive a client signal having a client rate that is one of a multiple different client rates, asynchronously map the client signal into a first frame of a first rate, asynchronously map the first frame into a second frame of a second rate, and output the second frame on the network; an intermediate node that is configured to receive the second frame, recover the first frame from the second frame, asynchronously map the first frame into a third frame of a third rate, and output the third frame on the network, where the intermediate node does not recover the client signal from the first frame; and an egress node that is configured to receive the third frame, recover the first frame from the third frame, recover the client signal from the first frame, and output the client signal. | 01-21-2010 |
20100254705 | HIGH-CAPACITY SWITCH - Consistent with the present disclosure, an optical switch is provided that switches multiple wavelength division multiplexed (WDM) optical signals. Each of the WDM signals includes optical signals having the same wavelengths. The WDM signals are supplied to optical splitters, which supply power split portions of the WDM signals to corresponding optical gates. Groups of the optical gates are associated with a corresponding switching block, which may include a cyclical arrayed waveguide grating (AWG), and the optical gates within each group are controlled so that one gate passes a received WDM signal portion while the remaining optical gates in the group are in a blocking configuration. As a result, the WDM portion received by the non-blocking gate is demultiplexed in the switching block and each of the wavelength components that constitute the selected WDM portion are supplied to corresponding outputs within the switching block. In a later time interval, a different optical gate may be rendered non-blocking so that a different WDM signal portion, supplied from a different optical splitter and carrying different information over the same wavelengths, may be input to the switching block. Thus, by controlling the optical gates, different WDM signal portions may be switched to, and thus demultiplexed by, a particular switching block. In addition, portions of the same WDM signal may be selectively supplied to different AWGs by appropriately control of the optical gates. | 10-07-2010 |
20110004700 | PROVIDING ACCESS TO CLIENT OVERHEAD WHILE TRANSPARENTLY TRANSMITTING THE CLIENT SIGNAL - A method includes receiving client data; extracting overhead data from the client data; mapping the client data into one or more frames, where each of the one or more frames has a frame payload section and a frame overhead section, where the client data is mapped into the frame payload section of the one or more frames; inserting the overhead data into the frame overhead section of the one or more frames; transporting the one or more frames across a network; extracting the overhead data from the frame overhead section of the one or more frames; recovering the client data from the one or more frames; inserting the extracted overhead data into the recovered client data to create modified client data; and outputting the modified client data. | 01-06-2011 |
20110004802 | METHOD AND SYSTEM FOR CONTROL OF COMMUNICATION EQUIPMENT BASED ON A BIT ERROR RATE DERIVED FROM A FRAME ALIGNMENT SIGNAL - Consistent with the present disclosure, circuitry may be provided in an optical receiver that can determine a bit error rate (BER) associated with an incoming signal by dividing the number of errored bits in a frame alignment signals (FAS) by the number of bits in the FAS. Accordingly, although an optical signal may be severely degraded and forward error correction (FEC) cannot be performed, a BER may be obtained if the FAS can be identified. The BER can then be used in a feedback loop to control various optical or electrical components in the receiver to improve or reduce the BER to a level, for example, at which FEC can be performed. | 01-06-2011 |
20110008039 | FORWARD ERROR CORRECTION (FEC) ENABLED PHOTONIC INTEGRATED CIRCUIT (PIC) CHIPS WITH MULTIPLE SIGNAL CHANNELS - A forward error correction (FEC) communication device that includes a transmitter photonic integrated circuit (TxPIC) or a receiver photonic integrated circuit (RxPIC) and a FEC device for FEC coding at least one channel with a first error rate and at least one additional channel with a second error rate, wherein the first error rate is greater than the second error rate. The TxPIC chip is a monolithic multi-channel chip having an array of modulated sources integrated on the chip, each operating at a different wavelength, wherein at least one of the modulated sources is modulated with a respective FEC encoded signal. The TxPIC also includes an integrated wavelength selective combiner for combining the channels for transport over an optical link. | 01-13-2011 |
20110158229 | CLOCKING OF CLIENT SIGNALS OUTPUT FROM AN EGRESS NODE IN A NETWORK - Consistent with the present disclosure, client data, which may include multiplexed data sub-streams, is supplied to an ingress node of a network. Each sub-stream typically has a corresponding data rate, i.e., an original data rate, prior to multiplexing. The client data is encapsulated in a plurality of successive frames that are output from the ingress node and propagate, typically through one or more intermediate nodes, to an egress node. At the egress node, data rates associated with the sub-streams included in each frame are determined based on the amount of client data in each frame. The data rates are then averaged over a given number of frames to thereby filter any wander or deviation in the client data rate. Based on the averaged data rate, justification opportunities are added to the client data in each sub-stream, which are then multiplexed into frames that are output from the egress node. By including the justification opportunities, the effective rate of each sub-stream may be set equal to the original data rate when the sub-streams are demultiplexed after being output from the egress node. An advantage of the present disclosure is that the justification opportunities, are not generated based solely on clock signals generated by PLL circuits. As a result, fewer PLL circuits are required, thereby simplifying system design and minimizing power consumption. | 06-30-2011 |
20110235646 | METHOD AND APPARATUS FOR DETERMINING PROPAGATION DELAY IN A NETWORK - A propagation delay in the transmission of a frame from an initiator node to a peer node is determined by initially identifying a frame number and byte offset of a first incoming frame from the peer node at a time when the initiator node outputs a portion of a transmitted frame. The portion of the transmitted frame may be the first byte of a sub-frame within the transmitted frame. At the peer node, the frame number and byte offset of a second frame to be supplied to the initiator node is identified at a later time when the frame portion transmitted by the initiator node is received by the peer node, and such information is transmitted to the initiator node. Thus, since the frames output and received by the initiator node are typically of fixed duration, the frame number and byte offset of the incoming frame represent the time when the initiator node outputs the frame portion (a transmit time). In addition, the frame number and byte offset of the second frame represents the time at which the frame portion is received by the peer node (a receive time). Accordingly, by comparing the frame numbers and byte offsets of the first and second frames received from the peer node, a difference between transmit and receive times or propagation delay can be obtained. | 09-29-2011 |
20110249936 | TRANSMITTER PHOTONIC INTEGRATED CIRCUIT (TxPIC) CHIP - A photonic integrated circuit (PIC) chip comprising an array of modulated sources, each providing a modulated signal output at a channel wavelength different from the channel wavelength of other modulated sources and a wavelength selective combiner having an input optically coupled to received all the signal outputs from the modulated sources and provide a combined output signal on an output waveguide from the chip. The modulated sources, combiner and output waveguide are all integrated on the same chip. | 10-13-2011 |