Abstract: Examples associated with ring network uplink designation are disclosed. One example includes detecting an operable connection between a member of a ring network and an external network. The operable connection may be detected by the member of the ring network. A signal is provided to a ring network management daemon. The signal may indicate the member of the ring network has the operable connection to the external network. A signal is received from the ring network management daemon. The signal may designate the ring network as an active uplink to the external network. The operable connection between the ring network and the external network is activated. Once activated, the operable connection may facilitate communication between members of the ring network and the external network.

Abstract: Count tracking in distributed environments is described, for example, as in data centers where many sites receive data and a coordinator node estimates a sum of the data received across the sites. Count tracking may be used in database applications, search engines, social networking applications and others. In various embodiments sites and a coordinator node work together to implement a process for summing data received at sites, where the sum takes into account both increments and decrements. In examples, a site decides whether to notify the coordinator node of a new data item according to a sampling probability that is related to an estimate of the current global sum of the data input across sites. In some examples a multi-mode algorithm is implemented which increases or decreases communication between the sites and the coordinator node according to behavior of the estimated global sum such that communications costs are optimized.

Abstract: A local router stores a content distribution map that specifies a plurality of permitted multicast groups. The local router receives communications from user devices on an access-network side of the local router. Those received communications identify multicast groups for which user devices wish to receive data. The local router ascertains if those identified multicast groups are permitted multicast groups specified by the stored content distribution map. For multicast groups ascertained to be permitted multicast groups, the local router sends communications across a network-side interface requesting membership in those multicast groups. The local router may then receive data for those multicast groups and forward that data to user devices. For multicast groups identified in user device communications ascertained not to be permitted multicast groups, the local router sends no communications across the network-side interface requesting membership.

Abstract: Systems and methods for a multi-drop, unidirectional service in a network include, responsive to a source point, one or more drop points, and a routing consideration, computing a path in the network; causing establishment of the multi-drop, unidirectional service on the computed path, through one of a control plane and a Software Defined Networking (SDN) controller; and managing the multi-drop, unidirectional service through the one of the control plane and the SDN controller. The multi-drop, unidirectional service has the source point at an originating node, one or more drop points at associated intermediate nodes, zero or more intermediate nodes with no drop points, and one or more drop points at associated terminating nodes.

Abstract: Methods, systems, and computer programs are presented for managing a network in the presence of layer-2 loops. One method includes an operation for detecting, by a network device, a loop at a layer 2 of a network. The network device is configured to execute a network device operation system (ndOS), where network devices executing ndOS share a global switch table. The method further includes an operation for blocking ports associated with the loop where incoming packets received at the blocked ports are discarded except for loop-probe packets. Further, the method includes operations for sending loop-probe packets by one or more network devices executing ndOS through one or more ports, and for unblocking a first port of the blocked ports based on the loop-probe packets when a lack of receipt of a loop-probe packet within a predetermined amount of time is detected for the first blocked port which indicates that the first blocked port is not part of the loop.

Abstract: A method provided in one example embodiment includes detecting a first current bandwidth of a first link in a network ring, where the first current bandwidth indicates a signal degradation on the first link. The method also includes determining whether the first current bandwidth has degraded more than a second current bandwidth of a second link in the network ring, where the second current bandwidth indicates a signal degradation on the second link. The method further includes routing one or more network flows away from the first link if the first current bandwidth has degraded more than the second current bandwidth.

Abstract: Methods, computer systems, and computer program products for improving resiliency in computing components functioning according to a multilayered Open Systems Interconnection (OSI) model in a network architecture running Ethernet or Internet protocols by a processor device are provided. Upon detection of at least one of a certain event within a specified layer of a network architecture, a notification of the event is provided in an inter-layer basis, such that the responsible entity manages the event according to an OSI model-wide system.

Abstract: An optical transceiver for use in network device in a packet network is provided. The network device may not be capable of providing a ring topology without use of the apparatus. The network device is configured to support at least two optical interfaces and an electrical interface, and coupled to an optical link. The optical transceiver includes a memory, a processor coupled to the memory, and a scheduler coupled to the processor. The scheduler of the optical transceiver is configured to perform as an information base for forwarding and transferring of packets and to use an optical link as a packet buffer.

Abstract: Provided are a method, a system and a node for implementing APS in an OBRing network. The method comprises: a master node and a slave node separately perform optical power monitoring on respective channels, and aggregate monitoring results to the master node; when determining, according to the monitoring results, that a fault occurs, the master node sends a switching operation instruction to the slave node; and the slave node performs a switching operation and enters a protection working state. With the disclosure, a protection switching mechanism is introduced to the OBRing, which implements the processing on fault and ensures the communication quality of the OBRing.

Abstract: A method for routing data in a network including a plurality of nodes connected by links, the method includes collapsing first and second rings of the nodes together, for each of the nodes in the network, determining a shortest path tree to each of the other nodes in the network, and for data sourced from a particular one of the nodes in the network, blocking the link or links not included in the shortest path tree determined for the particular one of the nodes. Also, a system for routing data through a network having a plurality of nodes connected by links, includes a ring collapsing module for collapsing first and second rings of the nodes together, a shortest path tree calculation module for determining, for each of the nodes, a shortest path tree to each of the other nodes in the network, and a link blocking module for blocking the link or links not included in the shortest path tree determined for data sourced from a particular one of the nodes.

Abstract: A method for providing a protection switching service in a virtual tenant network (VTN) and a controller are provided. The method enables a real-time protection switching setup on a VTN path in order to provide reliability of a VTN service.

Abstract: Methods and systems are provided for managing an Ethernet ring protection switching (ERPS) protocol in an Ethernet network. The method includes receiving an administrative data packet at a first network element; determining whether the administrative data packet contains an ERPS membership setting from a second network element; when the administrative data packet contains the ERPS membership setting from the second network element, comparing an ERPS membership setting at the first network element to the ERPS membership setting from the second network element; and performing an action when the ERPS membership setting at the first network element is different than the ERPS membership setting from the second network element.

Abstract: Methods and systems are provided for migrating loop-breaking protocols in an Ethernet network. The method includes selecting a virtual local area network (VLAN) implementing a multiple spanning tree protocol (MSTP) from a plurality of VLANs operating on the Ethernet network, the MSTP having a spanning tree with a root network element coupled to a first branch of network elements; disabling a virtual network link in the VLAN; migrating a first leaf network element of the first branch in the VLAN by disabling the MSTP and enabling an Ethernet ring protection switching (ERPS) protocol on the first leaf network element; migrating the root network element in the VLAN after the first leaf network element by disabling the MSTP and enabling the ERPS protocol on the root network element; and enabling the virtual network link after migrating the first leaf network element and the root network element.

Abstract: Logic may decide which service advertisement information to transmit in a service advertisement frame based on link margin information of each service advertisement received. Logic may filter the service advertisement information to avoid advertising service information for service providers that cannot be reached. A first station may receive a service advertisement from a second station and determine whether to include the service advertisement with a transmission of the first station's service advertisement based upon perceived proximity of the second station. A station may generate a Leaving Message if a user terminates service advertisements of the station or the station appears to be moving away from a service advertisement group. In response to receiving a Leaving Message from a neighboring station, a station may remove the neighboring station from a list of service providers maintained by the station.

Abstract: A system and method of failure detection in rings includes a switch including a control unit, one or more first ports coupled to the control unit and configured to couple the switch to a ring of switches in a first direction, and one or more second ports coupled to the control unit and configured to couple the switch to the ring of switches in a second direction opposite the first direction. The control unit is configured to detect a failure in the ring of switches in the second direction, transmit a request message in the first direction using one of the one or more first ports, receive a response message on one of the one or more first ports, extract reachability data from the response message, and determine one or more first switches in the ring of switches that are reachable in the first direction based on information associated with the reachability data.

Abstract: In one embodiment, a scheduling device in a network receives routing metrics regarding a network path between a device controller and a networked device. The scheduling device also receives controller metrics for the device controller. The scheduling device determines time costs associated with the network path and one or more control operations performed by the device controller, based on the routing and controller metrics. The scheduling device generates a communication schedule based on the time costs and instructs the device controller and the networked device to use the communication schedule.

Abstract: Aspects of the present disclosure describe systems, structures and methods providing fully reconfigurable optical add-drop multiplexing (ROADM) that provide redundancy protection against any two (2) simultaneous wavelength selective switch (WSS) failures with only four 2×1 WSS structures for both Eastbound and Westbound traffic, while not requiring bidirectional operation of the WSS structures.

Abstract: Techniques are described for enhancements to Protocol Independent Multicast (PIM) to support multicast only fast re-route (MoFRR) over a remote loop free alternate (RLFA) backup path in a network. This disclosure describes a modified PIM control message having a new PIM message type and an additional field to indicate an address of a RLFA network device in the RLFA backup path. According to techniques of this disclosure, network devices along the RLFA backup path are configured to forward the modified PIM control message toward the RLFA network device instead of toward a source of a requested multicast group. When the RLFA network device receives the modified PIM control message, the RLFA network device is configured to forward a conventional PIM control message towards the source of the requested multicast group. In this way, PIM can be used to provide MoFRR over a RLFA backup path.

Abstract: Methods and systems are provided for migrating loop-breaking protocols in an Ethernet network. The method includes disabling a port of a first leaf network element in a network implementing a rapid spanning tree protocol (RSTP), the RSTP having a spanning tree with a root network element coupled to the first leaf network element forming a first branch of the spanning tree; migrating the first leaf network element by disabling the RSTP and enabling an Ethernet ring protection switching (ERPS) protocol on the first leaf network element; migrating the root network element after the first leaf network element by disabling the RSTP and enabling the ERPS protocol on the root network element; and enabling the port of the first leaf network element after migrating the first leaf network element and the root network element.

Abstract: A receiver network component operates in a communication network of an automation system. The component receives data messages sent redundantly by transmitter network components of the communication network and rejects duplicates of an already received data message. Interoperability of network components from different manufacturers is ensured even for device-redundant transmitter network components and redundant transmission of data messages is achieve with comparatively low complexity. The receiver network component is prompted by reception of a current data message from one of the transmitter network devices to check whether a data message with identical useful data has already been received from another transmitter network component. The data message is processed if it is received for the first time and it is rejected as a duplicate if it is a data message with such useful data that have already been received in an earlier data message from another transmitter network component.

Abstract: A multi-port transmitter device for transmitting at least partly redundant data is described. The multi-port transmitter device comprises at least two transmitters comprising respective transmitter buffers. One transmitter is a master transmitter that issues a request to the processor to provide a data block when the transmitter buffer of the master transmitter has free space to store a data block. The processor is arranged to copy at least one data block of data stored in an external memory from the external memory to respective positions in a local buffer. The processor is arranged to, in accordance with a predefined sequence, sequentially initiate transfer of the data block from the respective position of the data block in the local buffer to the transmitter buffers of the at least two transmitters in response to a request from the master transmitter to provide a data block.

Abstract: A method for virtual local area network fail-over management, a system therefor and an apparatus therewith are introduced herein. In the method for virtual local area network fail-over management in a hybrid software-defined network (SDN), a controller with a centralized management authority may manage some fail-over events that occur in each link or switch in a centralized manner. The controller may pre-calculate backup paths for each link or switch in case that fail-over events occur therefrom. Whenever the fail-over event occurs in some specific link or switch, the controller may deploy the pre-calculated backup path in response to the link down or switch down event, which may reduce the convergence recovery time for the VLAN path in case of fail-over events and improve the reliability of data transmission.

Abstract: Ring bus architectures for use in a memory module are disclosed. A memory module may include a ring bus controller and a bus bridge positioned on a primary ring bus. The memory module also includes a secondary ring bus in communication with the bus bridge and a plurality of non-volatile memory units. The ring bus controller is configured to send a configuration command to the bus bridge via the primary bus ring, where the configuration command includes an indication to route future commands and/or data to the secondary ring bus extending from the bus bridge. The bus bridge is configuration to, in response to the configuration command, configure the bus bridge to route future commands and/or data from the primary ring bus to the secondary ring bus.

Abstract: The invention relates to a method for transmitting messages in a computer network, and to a computer network of this type. The computer network comprises computing nodes (101-105), said computing nodes (101-105) being interconnected via at least one star coupler (201) and/or at least one multi-hop network (1000), wherein each computing node (101-105) is connected via at least one communication line (110) to the at least one star coupler (201) and/or the at least one multi-hop network (1000), and wherein the computing nodes (101-105) exchange Ethernet messages with one another and with the at least one star coupler (201) and/or the at least one multi-hop network (1000).

Abstract: A circuit arrangement for connecting a bus participant to at least one bus, having an interface for connecting the bus participant to the circuit arrangement, a first bus input, and a first bus output between which the bus participant is switchable via the interface. The circuit arrangement includes a second bus input and output for connecting the bus to the circuit arrangement in a ring topology in such a way that the first bus output is connected at least indirectly to the second bus input and the second bus output is connected at least indirectly to the first bus input via the bus. The bus in the circuit arrangement can be separated to obtain a line topology and can be configured as bus-terminating at one of the bus inputs or bus outputs. A system for the functional testing of bus participants on a bus in a simulation environment is provided.

Abstract: An optical communication system with a hierarchical branch configuration. The system includes first and second cable landing stations coupled to a trunk path in an optical cable. At least one hub-node is coupled to the trunk path through an associated hub-node branching unit. Sub-nodes are coupled the hub-nodes through associated sub-node branching units and sub-node paths in the optical cable. Sub-node signals may be communicated between the sub-nodes and the hub-nodes without being provided on the trunk path.

Abstract: In one embodiment, a scheduling device in a network receives routing metrics regarding a network path between a device controller and a networked device. The scheduling device also receives controller metrics for the device controller. The scheduling device determines time costs associated with the network path and one or more control operations performed by the device controller, based on the routing and controller metrics. The scheduling device generates a communication schedule based on the time costs and instructs the device controller and the networked device to use the communication schedule.

Abstract: Techniques for sub-channel detection for wireless data communication are described. In at least some implementations, techniques can utilize subsets of available wireless channels for inter-device data communication. For instance, in at least some embodiments, a wireless connection between a client device and a wireless device can be established according to a pre-specified subset of sub-channels. Further, in at least some embodiments, a wireless device can be configured to transmit and/or receive data using a specific subset of sub-channels, while a client device can be configured to scan a larger set of sub-channels to search for data communication from the wireless device. The client device can detect transmitted signal from the wireless device at the subset of sub-channels, and can utilize the set of sub-channels for data communication between the wireless device and the client device.

Abstract: A first reconfigurable optical add/drop multiplexers (ROADM) and a second ROADM are connected by a primary light path and a protection light path. The first ROADM includes a first direction and a second direction, and the second ROADM includes a third direction and a fourth direction. The primary light path is coupled between the first direction and the third direction, and the protection light path is coupled between the second direction and the fourth direction. Transmissions on the primary light path are monitored, and when a problem is detected on the primary light path, the first and third directions are deactivated and the second and fourth directions are activated so that additional light signals are sent on the protection light path and not on the primary light path.

Abstract: A Layer 1 transport network, such as an Optical Transport Network (OTN), transports traffic in Layer 1 data transport units. Traffic received at a node of the transport network is mapped to Layer 1 data transport units according to destination such that each Layer 1 data transport unit carries traffic for a particular destination of the transport network. The Layer 1 transport network can carry a plurality of different traffic types and the node can map the received traffic to Layer 1 data transport units according to destination and traffic type. Identification information can be added to an overhead section associated with the Layer 1 data transport unit to indicate at least one of: traffic type and destination of the traffic carried within the data transport unit.

Abstract: This network comprising functional nodes connected in series by information transmission means, in which the information assumes the form of discrete messages propagating from node to node in the network, is characterized in that the information transmission means for transmitting information between the nodes are bidirectional so as to allow information to propagate in both directions of flow of the network, and each node includes at least one first and one second associated port, for information input/output, connected to adjacent nodes by corresponding information transmission means and the operation of which is controlled by communication automaton means, between an operating mode for the asynchronous reception of information from its adjacent nodes and an operating mode for the synchronous transmission of information to the nodes adjacent thereto, and in that the communication automaton means are suitable for triggering the activation of the communication of information from the node to its adjacent node

Abstract: Techniques are disclosed for workflow based high availability analysis in computing systems. For example, a computer-implemented method for analyzing an information network infrastructure to identify one or more availability weak points includes the following steps. A workflow specification is provided based on one or more user-visible processes and an application topology. Service workflows associated with the specification are mapped from the application topology to the infrastructure to generate a workflow data structure. An availability weak point analysis is performed in accordance with the workflow data structure to determine one or more optimal high availability parameters for one or more deployed components of the infrastructure. The one or more optimal high availability parameters are applied in the infrastructure so as to substantially eliminate the one or more availability weak points.

Abstract: In a configuration where an apparatus network is connected to a backbone network at two points, a first apparatus and a first switch device are normally communicatively connected to each other and also communication between a second apparatus and a second switch device is normally disconnected. The first apparatus monitors the link state with the first switch device. The second apparatus queries the first apparatus about the link state. When the first apparatus and the first switch device are not communicatively connected to each other or when the second apparatus cannot communicate with the first apparatus via the apparatus network, the second apparatus cancels the disconnected state with the second switch device.

Abstract: An apparatus and method to improve communications in a wireless communication network. Steps include sending specific information to user equipment or adjacent base stations so that the user equipment and adjacent base stations can determine minimum power requirements and interference levels in sidelink communications. The apparatus includes a localization module with a self-tracking component; a signal-detection component; and a location-estimation component. The apparatus may include a proximity system usable to locate one or more target transmitters and includes a localization module; a proximity-description module; and a proximity-display module. The proximity system may include a proximity advertisement module, which includes an access management component; an ownership management component; and a content management component.

Abstract: A network element includes first and second multiplexers, first and second interfaces, and first and second selecting units. The multiplexers are communicatively coupled. The first interface is communicatively coupled to the first multiplexer and configured to receive multiplexed signals. The second interface is communicatively coupled to the second multiplexer and configured to receive multiplexed signals. The first selecting unit is communicatively coupled to the first and second multiplexers and configured to select between a signal received from the first multiplexer and a signal received from the second multiplexer. The second selecting unit is also communicatively coupled to the first and second multiplexers and configured to select between a signal received from the first multiplexer and a signal received from the second multiplexer.

Abstract: In order to perform protection switching of a frame that is transmitted and received between a packet processor and a host processor, when an input frame is a receiving frame and a signal failure has occurred, by transporting a message including a protection switching command to a packet processor, protection switching is performed. Information representing that protection switching is performed is recorded in a header of the receiving frame, and a frame including a message including a corresponding header is transported to the host processor.

Abstract: A method for protection switching in an Ethernet ring network is provided. According to an aspect, the protection switching method includes: at a first node on the Ethernet ring network, detecting link failure; at the first node, determining whether a port through which a protection switching message has to be transmitted is on a forwarding path; and at the first node, generating a protection switching message based on the result of the determination; and at the first node, transmitting the protection switching message.

Abstract: Provided is a processor with a data transfer structure that is excellent in performance and efficiency. According to an aspect, the processor may include a plurality of processing elements, a plurality of routers respectively connected to the processing elements, and a plurality of connection links formed between the routers such that data is transferred between the processors via a network.

Abstract: A number of users interface with a network via a multiplex module, on a communication path established between the multiplex module and a point of presence. Some users may be served by one or more first channels of the communication path while one or more remaining users may be served by one or more additional channels of the communication path. Users having a basic service level agreement may be served by the first channels while users having an extended service level agreement may be served by the one or more additional channels. Allocation of users to distinct channel types based on their service level agreements may apply at a primary point of presence or may apply at a redundant point of presence.

Abstract: Provided is a method for determining topology of a network, including: all links of the network are divided into link sets L(V1), . . . , L(Vn) according to rate levels V1, . . . , Vn of links of the network, wherein n is a positive integer equal to or larger than 1; a link set L(Vx) is divided into link subsets L(Vx)1, . . . , L(Vx)k according to connectivities of the links, wherein 1?x?n and k is a positive integer equal to or larger than 1; and a network layer to which a link subset L(Vx)y is attributed is determined, wherein 1?y?k.

Abstract: Performing operations on nodes of distributed computer networks. A request to upgrade a first acceleration node in a computer network is identified. A second acceleration node that is linked to the first acceleration node is identified. A bypass link to the second acceleration node from the first acceleration node is established. The bypass link is configured to transmit new connections received for handling by the first acceleration node to the second acceleration node for handling by the second acceleration node during upgrading of the first acceleration node. Upon establishing the bypass link, the first acceleration node is upgraded in response to identifying the request.

Abstract: In the case where a terminal under an RPR node (240) which does not belong to an interlink connection node group in an RPR network (20) transmits an Ethernet frame to a terminal under an RPR node of other RPR network (10), the RPR node (240) transmits an RPR frame in which the Ethernet frame is contained to any of interlink connection nodes (200, 230, and 270) in the same network. The interlink connection node which receives the RPR frame extracts the Ethernet frame from the RPR frame and transfers the extracted Ethernet frame to the other RPR network (10).

Abstract: The invention relates to a method of fault monitoring in a fault monitoring entity of a network node of a network having at least a first connection-oriented network layer, having first protection measures associated therewith, and a second connection-oriented network layer, having second protection measures associated therewith. In a first step the service condition status of the first network layer is monitored using the first protection measures. In a second step the second network layer protection measures are determined for onward transmission within the second network layer depending on the service condition status of the first network layer. Since the network node is aware of the monitored status condition of both the first and second layers the protection mechanisms for the first network layer and the second network layer can be co-ordinated and the second network layer protection measure for onward transmission may be determined for optimum network fault protection operation.

Abstract: A printer includes a main apparatus, a device including a drive unit operable by electric power from the main apparatus; and a connection member. The main apparatus includes a first power source and a first output port. The device includes: a first input port from which the electric power from the first power source is inputted; a protector with a first end connected to the first input port; a second output port connected to a second end of the protector and to output electric power from the protector to the outside thereof; and a second input port connected to the drive unit. The connection member includes a first connecting path to connect the first output and input ports and a second connecting path to connect the second output port to the second input port to supply the output from the second output port to the second input port.

Abstract: A computer-implemented method for calculating an effect on timing of moving a pin from an edge position to an inboard position in processing large block synthesis (LBS). The method includes determining first timing details at the inboard position, based on internal wire segments between a signal source and the inboard position. The method further includes selecting an upper metal layer as a virtual wire between the edge position and the inboard position. The method further includes calculating capacitance and resistance of the virtual wire. The method further includes updating driver strength of a driver between the signal source and the inboard position. The method further includes determining second timing details at the inboard position, based on wire loads of the virtual wire. The method further includes modifying an assertion of the pin at the inboard position, based on the first timing details and the second timing details.

Abstract: An external module, an electronic device and a method for driving an electronic module are provided. The electronic device includes a host and multiple external modules. The external module adapted to be removably connected to the electronic device includes a body, a first connector, a moving assembly and a second connector. The body has multiple connecting ports. The first connector is fixed on one of the connecting ports. The electronic device is adapted to be electrically connected to the first connector for providing power to the external module to drive the moving assembly. The second connector is assembled to the moving assembly disposed in the body and electrically connected to the first connector. The moving assembly drives the second connector to switch between the connecting ports, and the connecting port where the second connector is located is different from the connecting port where the first connector is located.

Abstract: A first wireless access network node sets a synchronization indication based on whether the first wireless access network node is synchronized with a synchronization source. The first wireless access network node transmits the synchronization indication.

Abstract: A method of routing traffic through a packet network having a mesh physical topology. At least two types of network primitive are defined, each type of network primitive providing a respective model of traffic forwarding through at least two neighbor nodes of the network. A network model encompassing at least a portion of the network is constructed using a set of two or more interconnected network primitives. The network model has nodes and links corresponding to respective nodes and lines of the network. Respective forwarding information is computed for each node of the network model. For each node of the network model, the respective computed forwarding information is installed in a forwarding database of the corresponding node of the network, such that traffic is forwarded by each node of the network in accordance with the respective computed forwarding information.

Abstract: A packet forwarding device includes: an evaluation unit configured to judge whether or not authentication information is stored in a header, the authentication information being for authenticating communication quality control information stored in the header of a packet transmitted via a network, and evaluate whether or not the authentication information is proper, the evaluation being made when the authentication information is stored in the header; and a forwarding unit that configured to control a communication quality using the communication quality control information, and forward the packet toward a transmission destination, the control being made when the authentication information is evaluated by the evaluation unit to be proper.

Abstract: Methods and nodes are disclosed for the support of traffic protection and recovery in mesh networks having multiple nodes communicating via communication links. The problem of timely and reliable Shared Mesh Protection message delivery is addressed through creation of protocols and encoding of Shared Mesh Protection messages within an overhead of the optical data unit container, and by processing the Shared Mesh Protection messages by intermediate nodes of the mesh network. Thus, the Shared Mesh Protection messages are transmitted through the data plane with the transmission of user data.