Abstract: A network management system includes a network interface communicatively coupled to one or more network elements in a network for exchanging Operations, Administration, Maintenance, and Provisioning (OAM&P) data; a processor communicatively coupled to the network interface; and memory storing instructions that, when executed, cause the processor to obtain the OAM&P data from the network, provide a Graphical User Interface (GUI) based on the network from the OAM&P data, wherein the GUI includes a network map which provides a topological view and a subway view which provides a detailed device-level view which is more granular than the network map and illustrates individual components at each site, receive a selection from a user of a service in the network, and update the GUI to highlight the service in the network map and illustrate the associated sites in the subway view.

Abstract: A transmitter (200) generates (602) an encoded vector (404) by encoding (406) a data vector (402), the encoded vector representing payload information and parity information. The encoding is mathematically equivalent to calculating three or more forward error correction (FEC) codewords from the data vector and then calculating the encoded vector from the codewords, at least one codeword being calculated from at least one recursion of a mathematical operation, and at least one codeword comprising more than 6 terms. The transmitter transmits (604) a signal representing the encoded vector over a communication channel. A receiver (300) determines (702) a vector estimate (502) from the signal and recovers (716) the data vector from the vector estimate by sequentially decoding (706, 710, 714) the codewords, wherein at least one codeword that is decoded earlier in the decoding enhances an estimate of at least one codeword that is decoded later in the decoding.

Abstract: An optical modulator includes multiple segments including modulator segments and a Radio Frequency (RF) crossing segment where RF lines extending a length of the modulator cross one another. The present disclosure includes optimization of one or more of a geometry of the RF crossing and a location of the RF crossing segment along the length. The geometry is selected so that the RF crossing segment appears as another segment having similar characteristics as modulator segments. The location of the RF crossing segment is selected to balance out fabrication error and phase efficiency.

Abstract: An electrical circuit package includes an electrical processing engine circuit configured to perform data processing; and one or more co-packaged coherent optical Input/Output (IO) modules interconnected to the electrical processing engine circuit, wherein the electrical processing engine circuit is configured to interface electrical data including an optical signal waveform representation to each of the one or more co-packaged coherent optical IO modules, and wherein the one or more co-packaged coherent optical IO modules are configured to coherently transmit and receive optical data based on the optical signal waveform representation. The electrical processing engine circuit can be configured to perform optical modulation and demodulation based on the optical signal waveform representation, in addition to the data processing.

Abstract: Systems and methods for automatically upgrading a license in a communication network are provided. In one embodiment, a network device in communication with a license server may be configured with a processing device and a memory device configured to store a computer program having instructions that, when executed, cause the processing device to analyze a communication path between first and second nodes of a communication system and analyze a first license agreement having a first set of constraints regarding communication between the first and second nodes. Responsive to determining that the communication path is not allowable under the first set of constraints of the first license agreement, the instructions may further cause the processing device to upgrade the first license agreement to a second license agreement having a second set of constraints that are less-restrictive than the first set of constraints regarding communication between the first and second nodes.

Abstract: Automatic optical link calibration systems and methods include an optical node with an Optical Add-Drop Multiplexer (OADM) multiplexer including a channel holder source; an optical amplifier connected to the OADM multiplexer and to a fiber span; an Optical Channel Monitor (OCM) configured to monitor optical spectrum before and after the optical amplifier; and a controller configured to obtain data associated with the fiber span including measurements from the OCM, determine settings of the channel holder source needed to meet a target launch power profile for the fiber span, and configure the channel holder source based on the determined settings.

Abstract: Systems and methods include receiving incoming packets associated with flows in a data center network where the flows are forwarded on a per-packet basis; maintaining a state of each of the flows and of received incoming packets; and dequeuing the received incoming packets based on one or more packet dequeue conditions and the state. The edge switch can be one of a Top of Rack switch and a Network Interface Card (NIC) communicatively coupled to a corresponding server. The received incoming packets can utilize a transport protocol including any of Transmission Control Protocol (TCP), Xpress Transport Protocol (XTP), and Stream Control Transmission Protocol (SCTP).

Abstract: A receiver generates a stream of digital samples from an analog electrical signal that represents data conveyed to the receiver over a communication channel, where the stream of digital samples comprises current samples corresponding to a current timepoint, previous samples corresponding to a timepoint earlier than the current timepoint, and subsequent samples corresponding to a timepoint later than the current timepoint. The receiver generates previous, current, and subsequent phase offset signals based on the previous, current, and subsequent samples, respectively. The receiver uses the previous phase offset signal to adjust clock frequency and clock phase of the current samples, thereby resulting in current adjusted samples. The receiver adjusts clock phase of the current adjusted samples based on any one of the previous, current, and subsequent phase offset signals. In some examples, receiver adjusts the clock phase of the current adjusted samples based on the subsequent phase offset signal.

Abstract: Upon receiving a communications signal conveying symbols at a symbol period T, a receiver applies filter coefficients to a digital representation of the communications signal, thereby generating filtered signals having a shape in the frequency domain characterized by a bandwidth expansion factor ?, where components of the filtered signals correspond to angular frequencies ? = - ? ? ( 1 + ? ) T ? ? … - ? ? ( 1 - ? ) T , + ? ? ( 1 - ? ) T ? ? … + ? ? ( 1 + ? ) T . The receiver calculates first-order components from a first phase derivative of the components at a first differential distance, second-order components from a second phase derivative of the first-order components at a second differential distance, and composite second-order components from an average of the second-order components over multiple time intervals.

Abstract: A method at a receiver comprises receiving a signal conveying symbols at respective positions within a clock cycle, the symbols comprising a data set consisting of data symbols and a pilot set consisting of pilot symbols; determining detected phases of the symbols based on the signal; generating first phase estimates based on the detected phases of a subset of the pilot set, and reference phases of the subset of the pilot set, the first phase estimates being associated with the positions of the pilot set; and generating second phase estimates based on the detected phases of the pilot set, reference phases of the pilot set, and the first phase estimates, the second phase estimates being associated with the positions of the pilot set and of at least a subset of the data set; and applying rotations to the detected phases of the symbols based on the second phase estimates.

Abstract: Systems and methods for analyzing a root cause of issues in a network, such as an optical communication network, are provided. A method, according to one implementation, includes the steps of deriving symptoms indicative of issues in a network by utilizing performance data obtained from network elements in the network and storing the derived symptoms in a database. The method also includes the step of obtaining diagnostics from the network elements. Also, the method may include utilizing the database to compute distances between the derived symptoms and each of the diagnostics, whereby the computed distances may be configured to correspond to dissimilarities between the derived symptoms and the diagnostics. The distances are computed based on machine learning models, user feedback, and analytical functions. Also, the method includes analyzing a root cause of the derived symptoms based on a lowest distance selected from the computed distances.

Abstract: A network element configured to implement an Ethernet Virtual Private Network (EVPN) Virtual Private Wire Service (VPWS) Flexible Cross-Connect (FXC) local switching service includes a plurality of ports; and a switching fabric configured to switch traffic between the plurality of ports; wherein a set of ports is configured in a distributed Link Aggregation Group (LAG) with two nodes, and an inter-chassis link configured with a second network element, and wherein, responsive to a failure of the inter-chassis link, a distribution state of members in the distributed LAG is coordinated.

Abstract: Systems and methods for enhancing the Border Gateway Protocol (BGP) are provided. In one implementation, a computer-readable medium comprises instructions that, when executed, cause a network element to perform the steps of maintaining and tracking states of multiple Border Gateway Protocol (BGP) peers and routes while operating BGP within one or more Autonomous Systems. The instructions further cause the network element to detect one or more anomalies, based on the maintaining and tracking, as a number of the multiple BGP peers and/or routes scale in the one or more Autonomous Systems. Also, the instructions cause the network element to cause the processing of one or more remedial actions based on the one or more detected anomalies.

Abstract: Systems and methods include receiving first power snapshot from a receiving end of a foreign controlled link of the one or more foreign controlled optical links when there are no faults thereon; responsive to obtaining second power snapshot from the receiving end of the foreign controlled link, detecting a fault on one of at least one channel and part of the spectrum traversing the foreign controlled link; correlating the second power snapshot with the first power snapshots; and raising an indication of fault for the foreign controlled link based on the correlating.

Abstract: A system includes a network element having a housing that is configured for front-to-rear airflow; and a cooling apparatus located adjacent to the network element and having a housing that forms a cavity that is closed by the housing of the network element, wherein the cooling apparatus includes one or more fan units that are accessible via front access and wherein the one or more fan units are configured to draw the front-to-rear airflow from the network element into the cavity. This enables a front-to-back airflow design with rear fan access to be converted into a front-to-back airflow design with front fan access.

Abstract: A management system configured to manage one or more optical transmitters in an optical network utilizing an optical spectrum, wherein the management system is configured to track at least one of said multiple optical transmitters by specifying a spectral position and spectral width of the portion of the optical spectrum containing a coherent optical signal generated by the at least one optical transmitter, wherein the spectral width is ‘n’ bins where n is an integer greater than 1 and each bin is a same size.

Abstract: A silicon modulator where the doping profile varies along the lateral and/or longitudinal position in the transition zones to achieve improved performance in terms of optical attenuation or contact access resistance or both. A modulator includes a core; a first transition zone that is a P-side region adjacent to the waveguide core, the first transition zone has a first longitudinal doping profile; and a second transition zone that is an N-side region adjacent to the core on an opposite side as the first transition region, the second transition zone has a second longitudinal doping profile; the first longitudinal doping profile has a variation of doping concentration along a longitudinal direction in the first transition region to mimic a first lateral doping profile, and the second longitudinal doping profile has a variation of doping concentration along a longitudinal direction in the second transition region to mimic a second lateral doping profile.

Abstract: A node in a Segment Routing network includes a plurality of ports and a switching fabric between the plurality of ports, wherein, for an Ethernet Tree (E-tree) service, a port is configured to transmit a packet with a plurality of Segment Identifiers (SID) including a first SID, a second SID, and a third SID, wherein the first SID identifies one of multicast, ingress replication for broadcast, and a destination node including any of a node SID and an anycast SID, wherein the second SID identifies a service including the E-tree service, and wherein the third SID identifies a source of the packet. A second port of the node is connected to a customer edge, and wherein the third SID is based on whether the customer edge is a leaf node or a root node in the E-tree service.

Abstract: A network element includes a plurality of ports interconnected by a switching fabric, wherein a port includes a plurality of connections including an infrastructure connection that operates a Bidirectional Forwarding Detection (BFD) session and a group of connections that share a similar fate for a fault as the infrastructure connection; and a controller configured to detect a fault on the infrastructure connection via the BFD session, and cause a protection switch for one or more of the group of connections based on the fault on the infrastructure connection. The infrastructure connection and the group of connections can be Pseudowires (PWE) or Label Switched Paths (LSPs) in a Multiprotocol Label Switching (MPLS) network.

Abstract: Described are apparatus and methods for fractional synchronization using direct digital frequency synthesis (DDFS). A DDFS device includes a memory with N address spaces, a write port circuit configured to sequentially write a digital desired pattern into the N address spaces, a read port circuit configured to readout the digital desired pattern from the N address spaces using continuous sequential automatic addressing from 0 to N?1 at a memory operating frequency clock, where the memory operating frequency clock is based on a sampling frequency clock used for high-speed data processing, and an analog signal processing circuit configured to process a readout digital desired pattern into an analog representation; and output a synthesized frequency clock from the analog representation to a digital core, where the synthesized frequency clock is fractionally synchronized with the sampling frequency clock.