Abstract: A printed circuit board (PCB) assembly may include a component capable of sending or receiving high-speed differential signal pairs, a package that is connected to the component, and a PCB connected to the package. The PCB assembly may be used to support a first high-speed differential signal pair that includes a first differential signal and a second differential signal. The first differential signal may be capable of causing crosstalk onto a particular differential signal, of a second high-speed differential signal pair, while propagating through the PCB assembly. A set of interconnects may be used to intelligently route the first differential signal pair within the package and/or within the PCB. The set of interconnects may include a first interconnect to route the first differential signal away from the particular differential signal and a second interconnect to route the second differential signal toward the particular differential signal.

Abstract: An apparatus includes a memory and a processor operatively coupled to the memory. The processor is configured to partition a set of ports of an optical multiplexer into a set of port groups including a first port group having a first set of ports and a second port group having a second set of ports mutually exclusive from the first set of ports. The processor is configured to associate the first port group with a first router and associate the second port group with a second router. When the optical multiplexer is operatively coupled to the first router and the second router, the first router is operatively coupled to the optical multiplexer via the first set of ports and not the second set of ports, and the second router is operatively coupled to the optical multiplexer via the second set of ports and not the first set of ports.

Abstract: In some embodiments, an apparatus includes a first optical transceiver. The first optical transceiver includes a set of optical transmitters, an optical multiplexer operatively coupled to the set of optical transmitters, and a variable optical attenuator operatively coupled to the optical multiplexer. The variable optical attenuator is configured to receive a control signal from a controller of the first optical transceiver and modulate a signal representing control information with an output from the optical multiplexer. The control information is associated with the control signal and for a second optical transceiver operatively coupled to the first optical transceiver.

Abstract: In some embodiments, an apparatus includes a quadrature amplitude modulation (QAM) optical modulator which includes a first phase modulator (PM), a second PM, a tunable optical coupler (TOC), and an optical combiner (OC). The TOC is configured to split a light wave at an adjustable power splitting ratio to produce a first split light wave and a second split light wave. The first PM is configured to modulate the first split light wave in response to a first multi-level electrical signal to produce a first modulated light wave. The second PM is configured to modulate the second split light wave in response to a second multi-level electrical signal to produce a second modulated light wave. The OC is then configured to combine the first modulated light wave and the second modulated light wave to generate a QAM optical signal.

Abstract: In some embodiments, an apparatus includes a processor configured to receive a set of digital samples associated with a set of optical signals received at a coherent optical receiver. The set of digital samples is associated with a set of optical channels. Each optical channel from the set of optical channels is spaced from at least one adjacent optical channel from the plurality of optical channels. The processor is configured to calculate, for each optical channel from the set of optical channels, a spacing between that optical channel and at least one adjacent optical channel from the set of optical channels based on digital signal processing of the set of digital samples. The processor is configured to send a signal indicating, for each optical channel from the set of optical channels, the spacing between that optical channel and the at least one adjacent optical channel.

Abstract: In some embodiments, a system includes a super-channel multiplexer (SCM) and an optical cross connect (OXC) switch. The SCM is configured to multiplex a set of optical signals into a super-channel optical signal with a wavelength band. The OXC switch is configured to be operatively coupled to the SCM and a reconfigurable optical add-drop multiplexer (ROADM) degree. The OXC switch is configured to be located between the SCM and the ROADM degree and the OXC switch, the SCM, and the ROADM degree are configured to be included in a colorless, directionless, and contentionless (CDC) optical network. The OXC switch is configured to switch, based on the wavelength band, the super-channel optical signal to an output port from a set of output ports of the OXC switch. The OXC switch is configured to transmit the super-channel optical signal from the output port to the ROADM degree.

Abstract: Embodiments of the invention describe apparatuses, optical systems, and methods related to utilizing optical cladding layers. According to one embodiment, a hybrid optical device includes a silicon semiconductor layer and a III-V semiconductor layer having an overlapping region, wherein a majority of a field of an optical mode in the overlapping region is to be contained in the III-V semiconductor layer. A cladding region between the silicon semiconductor layer and the III-V semiconductor layer has a spatial property to substantially confine the optical mode to the III-V semiconductor layer and enable heat dissipation through the silicon semiconductor layer.

Abstract: The disclosed method may include (1) identifying a software update that includes at least one software function that has changed since a previous software update, (2) determining, based at least in part on the software update, one or more call paths that include (A) the software function that has changed since the previous software update and (B) at least one additional software function, (3) mapping the changed software function to one or more test scripts, (4) mapping the additional software function to one or more additional test scripts, (5) identifying at least one test script that is commonly mapped to both the changed software function and the additional software function, and then (6) performing a regression test by executing the test script that is mapped to both the changed software function and the additional software function. Various other systems, methods, and computer-readable media are also disclosed.

Abstract: In one example, a method includes receiving, by a first network device, a route advertisement message including an attribute for upstream allocation specifying a plurality of next hops of a second network device for reaching a network destination, a plurality of forwarding semantics describing forwarding actions and respective attributes of the plurality of next hops, and a field indicating whether the attribute is provided for downstream allocation or upstream allocation. The method includes in response to determining, by the network device, that the field indicates the attribute is provided for upstream allocation: installing, by the network device and based on the forwarding semantics, next hops, forwarding actions, and the next hop attributes; and applying based on the forwarding information, the forwarding actions to network traffic received by the network device and destined for the network destination when forwarding the network traffic to one or more of the plurality of next hops.

Abstract: The disclosed apparatus may include (1) at least one communication port that facilitates communication between a source computing device and a destination computing device via a path within a network and (2) a processing unit communicatively coupled to the communication port, wherein the processing unit (A) monitors the network for any changes to the path that potentially affect a maximum transmission unit of the path, (B) detects, while monitoring the network, a change to at least one hop included in the path, and then in response to detecting the change to the hop, (C) identifies a packet size that corresponds to the maximum transmission unit of the path, and (D) tests the path for an increase in the maximum transmission unit by transmitting a packet whose size is larger than the packet size that corresponds to the maximum transmission unit. Various other apparatuses, systems, and methods are also disclosed.

Abstract: A computer-implemented method for improving clock synchronization between master and slave devices may include receiving at least one clock-synchronization packet transferred from a master device to a slave device via a network that supports an IP. The method may also include identifying at least one item of IP information added to the clock-synchronization packet during the transfer from the master device to the slave device. The method may further include determining that the clock-synchronization packet experienced a delay that exceeds a predetermined threshold during the transfer based at least in part on the item of IP information. Finally, the method may include discarding the clock-synchronization packet from a set of clock-synchronization packets used to synchronize the slave device with the master device in response to the determination. Various other methods, systems, and computer-readable media are also disclosed.

Abstract: In some embodiments, an apparatus comprises an optical transponder which includes a processor, an electrical interface and an optical interface. The processor is operatively coupled to the electrical interface and the optical interface. The optical interface is configured to be operatively coupled to a plurality of optical links and the electrical interface is configured to be operatively coupled to a router such that the optical transponder is configured to be operatively coupled between the plurality of optical links and the router. The processor is configured to perform pre-forward error correction (FEC) bit error rate (BER) detection to identify a degradation of an optical link from the plurality of optical links. The processor is configured to make modifications to packets designated to be transmitted via the optical link in response to the degradation being identified such that the router is notified of the degradation of the optical link.

Abstract: A disclosed method may include (1) providing a network stack that includes both a native stack and a proprietary stack, (2) implementing at least one socket that represents an endpoint of a communication channel between a network device and a computing device, (3) identifying at least one packet to be forwarded from the network device to the computing device via the socket, (4) configuring the network stack such that (A) the native stack discovers a maximum transmission unit of a network path between the network device and the computing device in connection with the socket and (B) the proprietary stack fragments the packet into a plurality of segments that each comply with the maximum transmission unit of the network path, and then (5) forwarding, along the network path, the segments to the computing device. Various other systems and methods are also disclosed.

Abstract: The challenge of isolating a protocol peer(s) from routing information churn caused by to a peering protocol (e.g., due to updating the peering protocol, due to a bug in the peering protocol, due to a crash in the peering protocol, etc.) is solved by using a separate data store to isolate the protocol peer(s) from the peering protocol. The separate data store may: (a) receive, from at least one of the outside peering devices, incoming routing information; (b) store the incoming routing information received in a first storage system; (c) provide a copy of at least some of the stored incoming routing information received to a second storage system used by a process for selecting routes using the routing information, the process generating state information to be distributed (e.g.

Abstract: The disclosed apparatus may include (1) forwarding, along a network path, a test packet that is (A) destined for an invalid port on a destination device and (B) fragmented by an intermediary device within the network path according to an MTU value of a network interface on the intermediary device, (2) receiving an error packet sent by the destination device in response to having determined that the test packet is destined for the invalid port, (3) determining a PMTU value of the network path by identifying, within the error packet, a size of the largest fragmented segment of the test packet received by the destination device, and then (4) forwarding, along the network path, at least one packet sized to comply with the PMTU value such that the packet remains unfragmented upon reaching the destination device. Various other apparatuses, systems, and methods are also disclosed.

Abstract: The disclosed computer-implemented method may include (1) receiving, at a network device, a route update for one or more routes that direct traffic within a network that supports BGP, (2) identifying, within the route update, a BGP prefix and a plurality of protocol next-hop addresses that (A) identify a plurality of neighbors of the network device and (B) each correspond to the BGP prefix, (3) maintaining a single copy of the BGP prefix and each of the protocol next-hop addresses, (4) receiving a packet destined for a computing device that is reachable via at least one of the neighbors of the network device, and then (5) forwarding the packet to the one of the neighbors of the network device in accordance with the BGP prefix and the protocol next-hop address that identifies the one of the neighbors. Various other methods, systems, and apparatuses are also disclosed.

Abstract: In general, techniques are described for monitoring memory usage in computing devices. A computing device comprising a memory and a control unit that executes a kernel of an operating system having kernel sub-systems may implement the techniques. A memory manager kernel subsystem, in response to requests for amounts of the memory from other one kernel sub-systems, allocates memory blocks from the memory. The memory manager, in response to requests to de-allocate one or more of the allocated memory blocks, determines the corresponding requested amounts of memory and sizes of the de-allocated blocks. The memory manager then generates memory usage information based on the determined requested amounts of memory and the determined ones of the two or more different sizes. The memory usage information specifies usage of the memory in terms of the two or more different sizes of the allocated plurality of memory blocks.

Abstract: A network device that includes a plurality of packet processing components may receive traffic associated with one or more services. The network device may store state information for each of the plurality of packet processing components, while the plurality of packet processing components are receiving the traffic. The state information may include state configuration information and/or internal storage information. The state information may be stored using a data structure that is internal to the network device and external to the packet processing component. The network device may detect an error that prevents the packet processing component from processing at least a portion of the traffic. The network device may execute, based on detecting the error that prevents the packet processing component from processing at least the portion of the traffic, a recovery procedure that uses the state information to reset the packet processing component to an operational state.

Abstract: A device may monitor a communication between network devices for an error associated with the communication. The device may detect the error associated with the communication between the network devices. The device may perform a comparison of an error metric and a threshold error metric. The error metric may be associated with the error. The device may determine whether the comparison indicates that the error metric satisfies the threshold error metric. The device may identify a source of the error using a loopback test based on determining whether the comparison indicates that the error metric satisfies the threshold error metric. The device may provide error source information based on identifying the source of the error. The error source information may identify the source of the error.

Abstract: A network device may include multiple line cards and a switch fabric assembly electrically connected to the line cards. The switch fabric assembly includes: for each of the line cards, a line card connector providing electrical connectivity between the line card and one or more cables; a cable mesh assembly including the cables, the cables providing electrical connectivity between each line card connector and multiple switch connector groups; and multiple switch application specific integrated circuits (ASICs), each of the switch ASICs being electrically connected to one of the switch connector groups.