Abstract: When stored identifying information of a transmission target frame and identifying information of a received frame are equal, a node apparatus updates transmission feasibility information stored in association with the final destination of the received frame. The transmission feasibility information indicates feasibility of transmission to each of a plurality of adjacent node apparatuses being a transmission destination, and is updated so that feasibility of transmission to the transmission destination associated with the identifying information of the received frame indicates that “the transmission is infeasible”. The node apparatus transmits the received frame, when there is no adjacent apparatus to which transmission is feasible, and when the stored identifying information of the transmission target frame is equal to the identifying information of the received frame, to the adjacent node apparatus recognized as the origin in association with the identifying information of the received frame.

Abstract: The present invention relates to the development of a device, Cognitive Communication Hub (CCH) that combines multiple and hybrid physical layers to collaborate and establish a unified network. The heterogeneous network so formed supports a whole range of bandwidth and spectrum while providing quality of service and class of service. The routing algorithm of the device is designed to explore the best route that can optimally use hybrid networking technologies to make a connection. The device has multiple interfaces and acts in an adhoc fashion. It forms multiple parallel data paths between source and destination and hence provides fault tolerance as a break down in one path does not disconnect end to end connection.

Abstract: At least two different redundancy protocols are operated in parallel by network devices in an Ethernet network. Control is determined and assigned to one of two protocols to have total control over which ports in the network devices are active and which are blocked for transmission of user data and network data network traffic while allowing all control and monitor traffic to traverse the ring of network devices. Control and monitoring packets are transmitted by RSTP packets through all of the network devices in the ring while restricting the data ports of the network devices to transmit user data and data network traffic to the network devices connected in the line of the network devices. Parameters received in RSTP packets are collected from all of the network devices in the ring in order to determine which network device of the network devices is a virtual root bridge.

Abstract: A method for managing a topology of a multi-ring Ethernet and a system thereof are disclosed, and the method includes: a node including a blocked port on the multi-ring Ethernet periodically sending a Topology Find Frame (TF) message along a transmission control channel through an own good port; a node receiving said TF message in the multi-ring Ethernet updating an own topology database according the NODE_LIST in said TF message, writing an own NODE_ID into the NODE_LIST of said TF message, and then forwarding said TF message along the transmission control channel.

Abstract: When stored identifying information of a transmission target frame and identifying information of a received frame are equal, a node apparatus updates transmission feasibility information stored in association with the final destination of the received frame. The transmission feasibility information indicates feasibility of transmission to each of a plurality of adjacent node apparatuses being a transmission destination, and is updated so that feasibility of transmission to the transmission destination associated with the identifying information of the received frame indicates that “the transmission is infeasible”. The node apparatus transmits the received frame, when there is no adjacent apparatus to which transmission is feasible, and when the stored identifying information of the transmission target frame is equal to the identifying information of the received frame, to the adjacent node apparatus recognized as the origin in association with the identifying information of the received frame.

Abstract: A method for redundant communication in a communication system having a plurality of communication networks connected to one another by at least one node, wherein data that originates from a first communication network is prevented from being transmitted back from the second the communication network into the first communication network as a result of information that is predefined before the transmission.

Abstract: Various embodiments provide a method and apparatus of providing a non-overlapping ring-mesh network topology which reduces costs (e.g., the number of network links) while providing resiliency to failure and meeting QoS requirements (e.g., network delay attributed to traversing the network architecture). In particular, a set of target nodes belonging to a cluster are connected through N rings. Each node is member of all N rings and no link between nodes in a ring is duplicated in another ring.

Abstract: In accordance with an example embodiment, there is disclosed herein, an apparatus having first and second interfaces for communicating on a ring network. Upon receipt of a first signal on the first interface indicating a break in the ring, the apparatus stops forwarding packets onto the ring. Upon receipt of a second signal on the second port indicating a break in the ring, the apparatus forwards all packets destined for the ring network onto the ring network via both the first and second interfaces.

Abstract: A set of virtual local area networks (VLANs) are defined from a set of nodes that comprise a data center network. A set of possible paths are determined for routing data packets from a root node to one or more other nodes of the set of nodes. A set of probabilistic values are identified for determining a path in the set of possible paths that individual data packets are to take as between the root node and a destination node specified by the individual data packet. The data packets are routed to the destination node specified by that data packet, along a path that is determined by use of the set of probabilistic values. The path may be provided by one or more VLANs.

Abstract: A dual-ring computer network architecture for industrial automation systems includes a dual-ring switch for interconnecting two networks, such as Rapid Spanning Tree Protocol (RSTP) networks. The dual-ring switch may provide separate control planes between the two networks but a common data plane between the networks. The system topology may include a main ring and a sub-ring, which creates separate fault regions for isolation. Using this configuration, the standard RSTP practical limit of 32 devices is no longer a limit, as the use of the dual-ring switch provides a mechanism to expand the total number of devices up to 256 while maintaining the network recovery time to within a target of 50 milliseconds. This allows for the use of dual rings using the RSTP protocol on a single switch. In another embodiment, two dual-ring switches are configured in the same sub-ring for redundancy.

Abstract: Methods for distributing content in an entertainment system are provided. The entertainment system includes a plurality of clients connected in a bi-directional loop configuration. Each of the plurality of clients has at least one associated video display unit. The method includes deriving a content distribution plan for distributing content files to the plurality of clients based on a theoretical symmetric system where each of the plurality of clients in the symmetric system is configured to store at least a fraction of each of the content files; and applying the derived content distribution plan for distributing content files to an actual entertainment system wherein each of the content files are stored in full in at least one of the plurality of clients of the system to provide an actual content distribution plan for the actual entertainment system. Related entertainment systems and content distribution modules are also provided.

Abstract: The present invention provides a method for forwarding a protocol frame in spanning rings, applied to the Ethernet ring network including a crossed or tangent ring and sub-ring. The method comprises steps as follows: when an interconnection node of the ring and the sub-ring receives a protocol frame from a sub-ring, if the topology of the sub-ring is changed, the interconnection node updates its address forwarding table according to the address updating information carried in the protocol frame, and sends the address updating information to the ring; the nodes of the ring update their address forwarding table respectively according the updating information. The present invention selectively sends information of sub-ring protocol frame to the ring via the interconnection node of the ring and the sub-ring.

Abstract: Embodiments of the present invention disclose a packet processing method and system. In the method in the embodiment of the present invention, because a root node configures different control VLANs for any two rings that have an adjacent edge in an area, different control VLANs are used to transmit a protocol packet in a ring that has its own control VLAN configured. The method and system may be applied to a ring network of a metro Ethernet to provide multi-path protection and implement rapid convergence of service switchover. In addition, a network topology structure is not limited to a network topology with a single ring or only two intersecting points, and may be applied to all network topology situations.

Abstract: A signal generation unit 107 and a first set value processing unit 7100 are included in a preceding stage of a transmission path connection unit 108 at a transmission side, and a signal generation unit 207 and a second set value processing unit 7200 are included in a subsequent stage of a transmission path connection unit 208 at a receiving side. The signal generation unit 107 or the signal generation unit 207 performs prescribed signal processing based on a set value. The first set value processing unit 7100 inputs a set value, that has been prescribed for the signal generation unit 107, to the signal generation unit 107, and the second set value processing unit 7200 inputs a set value, that has been prescribed for the signal generation unit 207, to the signal generation unit 207.

Abstract: A method, system and machine-readable storage medium for providing fault tolerance in a distributed mobile architecture (dMA) system. The method includes receiving a message or failing to receive the message within a predetermined time relating to a first dMA gateway (dMAG) at a second dMAG. It is determined whether the first dMAG is not operational or is otherwise offline based on the received message or the failure to receive the message. One or more dMA nodes associated with the first dMAG are notified in order to request connections to an external system via the second dMAG. The external system is also notified to request connections to one or more dMA nodes associated with the first dMAG via the second dMAG.

Abstract: An Ethernet protection and loadsharing capability is provided. The Ethernet protection and loadsharing capability enables co-existence of both protection and loadsharing for an Ethernet tunnel, having a plurality of associated Ethernet paths, between first and second Ethernet switches. The first Ethernet switch receives configuration information associated with the Ethernet tunnel between the first and second Ethernet switches, and processes the configuration information for causing the first Ethernet switch to associate the Ethernet paths of the Ethernet tunnel with an Ethernet tunnel endpoint object associated with an Ethernet tunnel. The first Ethernet switch, upon receiving traffic intended for the second Ethernet switch, propagates the traffic from the first Ethernet switch toward the second Ethernet switch via at least a subset of the Ethernet paths of the Ethernet tunnel using protection and/or loadsharing.

Abstract: Systems and methods of automatically determining a set of route targets is provided. The method includes receiving network topology data specifying configuration of a network. The method also includes automatically converting the network topology data into route targets to be assigned to virtual routing and forwarding elements. The route targets are grouped into sets and duplicate sets of route targets are removed. The method further includes generating a data record including information related to the set of route targets.

Abstract: A backup system of a ring network and a backup method of a ring network are provided. The backup system of a ring network includes a plurality of switches. Each switch includes two main connection ports and two redundant connection ports. One of the two main connection ports of each switch is connected to one of the two main connection ports of an adjacent switch via a main link, and one of the two redundant connection ports of each switch is connected to one of the redundant connection ports of an adjacent switch via a redundant link. The main links are preset to be in a work state, and the redundant links are preset to be in a backup state. When one of the main links is faulty, the redundant link corresponding to the faulty main link is converted to be in the work state.

Abstract: Techniques are identified for optimizing the MAC flush in Ethernet rings for faster traffic restoration. In one embodiment, flushing of MAC addresses is performed only once on receiving a first control message. For example, when a first control message is received, a network device may switch from a first state to a second state, which may indicate that the MAC addresses are not to be flushed if additional control messages are received. In another embodiment, flushing of MAC addresses is performed on one ring port rather than on both ring ports. For example, a flag field of a control message header may be used to determine on which port to flush. In another embodiment, flushing of MAC addresses is performed on only one ring port of an interconnection node. For example, the ring port can be determined using a flag field and possibly labels associated with the ring ports.

Abstract: Techniques are described which provide mechanisms for dual-homing an access ring for virtual private wire service (VPWS) Ethernet line (E-Line) services. The mechanism may provide resiliency against access ring failures and offer a restoration time of 50 msec upon failure. A method to provide such resiliency may generally include determining, at a first ring port of an access node, a ring failure in an Ethernet ring. Upon determining the first ring port of the access node is not situated on a same side of the Ethernet ring as a node designated as a ring protection link (RPL) owner, a message is transmitted on a second ring port of the access node towards a provider edge (PE) node. The message is used to activate pseudowires (PWs) at the PE node for virtual local area networks (VLANs) of the access node.

Abstract: A ring-based network and a construction method thereof, comprising a plurality of nodes and a plurality of links. In an initial status, each node compares each first link-up packet and fills a priority value in the first link-up packet with the higher priority value to form a second link-up packet. The priority value of each node and the highest priority value of each adjacent node recorded in each node are compared with each second link-up packet. When the priority value of the node and the highest priority values of adjacent nodes recorded in the node are smaller than the second link-up packet, the ring port of the node is situated at a forward status. According to the forward status or a blocked status of the ring port, these links form a plurality of forward links and a blocked link respectively.

Abstract: A system including a first physical network interface card (NIC) include a number of rings, where at least one of the rings is an active ring. The system further includes a host, operatively connected to the first NIC, and including Media Access Control (MAC) layer. The MAC layer is configured to obtain a power management policy, obtain a load associated with the active ring, determine, using the power management policy and the load, that the state associated with at least one of the rings must be changed, and change, in response to the determining, the state of at least one of the of rings.

Abstract: There is provided a method for managing an Ethernet ring network of a VLAN-based bridge that includes: registering a major-ring VID (VLAN ID) in a ring port filtering database of a ring protection link owner node in accordance with a request for registering the major ring VID (VLAN ID) from an ERP (Ethernet Ring Protection) controller mounted on the ring protection link owner node of a major ring; delivering, by the ring protection link owner node, a VID registration message to other nodes which belong to the major ring through a ring port; receiving the VID registration message through the ring port and registering the major ring VID in a ring port filtering database of each node itself, by each node which belongs to the major ring; and delivering, by each node which belongs to the major ring, the VID registration message to other nodes which belong to the major ring through the ring port.

Abstract: A mesh network architecture is disclosed whose protected services can be restored quickly after the failure of a network element (i.e., a network node, a network transmission facility). Furthermore, the protected services can be restored after all single and most multiple network-element failures as quickly as a ring network can recover from a single network-element failure. And still furthermore, the illustrative embodiment is also advantageous in that it can be administered and maintained, for most purposes, as a collection of distinct ring networks. Embodiments of the present invention can use any protocol or transmission technology (e.g., wavelength division multiplexing, SONET/SDH, ATM, etc.). Furthermore, embodiments of the present invention distinguish between the transport function, the provisioning function, and the fault notification functions of a network and provide that each of the functions can be accomplished by different networks using different protocols.

Abstract: A method for transmitting data in a layer two network having layer three routing capabilities includes transmitting, via a physical loopback, the data from a layer two switching component of a multi service platform to a layer three switching component of the multi service platform. The data specifies an initial routing path for the data that identifies a first layer two switch, and the method includes determining a new routing path for the data, the new routing path identifying a second layer two switch different than the first layer two switch. The method also includes updating the data to specify the new routing path, and transmitting, via the physical loopback, the data that specifies the new routing path from the layer three switching component to the layer two switching component.

Abstract: An optical ring network has one or more working wavelengths and multiple protection wavelengths adapted to support the working wavelength(s). Routing tables may be used in network nodes to assign traffic of a failed working wavelength to a protection wavelength. The protection technique may be applied to networks employing, for example, Dense Wave Division Multiplexing (DWDM).

Abstract: Apparatus and method are provided for distributing service domain reachability information across domain boundaries, thereby allowing domain management systems to determine routing for cross-domain services even when the domains have different technologies or administrators. A Service Domain Manager within each domain advertises to neighbouring domains which services it supports. A domain which receives such advertisements forwards the advertisement on to other domains. Each SDM builds a routing information table which specifies the service, the domain, the next hop, and optionally user defined metrics. The routing information table does not include end-point addresses, in order to keep the size of the table manageable. In this way, the NMS of each domain obtains an end-to-end view of service routes.

Abstract: In a communication device for monitoring a network system where a frame is transferred, with a maintenance frame for maintenance and management, an input-output section inputs or outputs a frame. A failure detection section detects occurrence of a failure in the network system on the basis of the inputted frame. A setting section sets the communication device according to the detection of the failure so as to terminate or transfer a data frame inputted from the input-output section. A data frame control section controls whether to terminate or transfer the data frame, according to the setting of the data frame by the setting section. A maintenance frame control section controls whether to terminate or transfer the maintenance frame inputted from the input-output section, according to the setting of the data frame by the setting section.

Abstract: A communication system includes communication devices that are connected with one another in a ring via a serial link. In the communication system, one communication device issues a standby packet for causing each communication device connected to a part of the link that is not involved with data transfer to switch to standby mode. Each communication device connected to this part of the link relays the standby packet from an immediately preceding communication device in the link to an immediately succeeding communication device in the link, and after relaying the standby packet, causes the own device to switch to standby mode. Further, a communication device that performs communication with said one communication device issues a loopback packet for causing each communication device connected to a part of the link that is involved with data transfer to switch to loopback mode.

Abstract: In accordance with an example embodiment, there is disclosed herein, an apparatus having first and second interfaces for communicating on a ring network. Upon receipt of a first signal on the first interface indicating a break in the ring, the apparatus stops forwarding packets onto the ring. Upon receipt of a second signal on the second port indicating a break in the ring, the apparatus forwards all packets destined for the ring network onto the ring network via both the first and second interfaces.

Abstract: A method for operating a redundant ringlike communications network, that communicates bidirectionally, includes communicating at least one primary participant and at least two secondary participants with one another by a data transmission device; communicating the secondary participants with one another directly by the data transmission device, indirectly by the primary participant and the data transmission device, or both; and exchanging by the participant the data to be exchanged between the secondary participants, between its data transmission device connections.

Abstract: A method, an apparatus and a system for interconnected ring protection, relates to the communication field, realizes the protection of the interconnected ring network using a narrow bandwidth, and improves the bandwidth utilization rate. The method comprises: a first intersection node in an intersection node group receiving an cross-ring service, the first intersection node determining an off-ring node of the cross-ring service on a second ring according to service information of the cross-ring service; and if the first intersection node does not communicate with the off-ring node of the cross-ring service on the second ring, and the first intersection node is not the last intersection node, the first intersection node forwarding the cross-ring service to a second intersection node.

Abstract: Apparatuses, methods, and computer-readable media support diagnosing a communications network using a network protocol that ensures a loop-free topology to prevent bridge loops. One of the network devices is identified as a selected device in a network ring, where the selected device interacts with the network ring through first and second ports. The values of some of the parameters of the selected device are modified to be distinguishable from that of any network device in the ring, and diagnostics about the functioning of the network protocol are then performed to obtain state information about the first and second ports. When one of the ports is determined to be in the blocking state, network redundancy for the network ring is verified. However, when neither of the ports is not in the blocking state, a redundancy problem may be detected.

Abstract: A method performed on a network element employing Multi-protocol Label Switching (MPLS) to optimize bandwidth in a ring topology network including a back-up Label Switch Path (LSP) for a protected LSP by re-routing traffic onto the back-up LSP to avoid shared links between the protected LSP and back-up LSP, including receiving a first labeled packet from another label switch router (LSR) in the back-up LSP, the first labeled packet indicating protection switch of data from the protected LSP to the back-up LSP, determining whether a shared link in the ring topology network exists between the protected LSP and the back-up LSP, rerouting traffic for the protected LSP onto an optimized back-up LSP to remove the shared link, receiving a second labeled packet indicating that a protection switch of data, and restoring routing of the traffic onto the protected LSP in response to receiving the second labeled packet.

Abstract: A graceful restart (GR) method of a router, and a router and a communication network thereof are provided. The method includes the following steps. A control plane enters a GR state. Label switched path (LSP) packets sent by a neighbor router are received, and the label information of the control plane is recovered according to the LSP packets. Whether the label information is completely recovered is determined. If the label information is completely recovered, the GR state is exited, and label information of a forwarding plane is updated according to the recovered label information of the control plane. The GR method of a router, the router, and the communication network decide whether to exit the GR state by detecting whether the label information of the control plane is completely recovered. This can precisely control the time of exiting the GR state is controlled and improve the reliability of the router.

Abstract: A method and device for transmitting a control message based on a multi-ring Ethernet are provided, wherein the method comprises the following steps: control virtual local area networks of a main ring and a sub-ring are configured (S1002); and a main ring node receives a sub-ring control message from the sub-ring, forwards the sub-ring control massage to the other main ring nodes on the main ring via a data plane, and synchronously realizes the blocking or opening of the sub-ring control message and a data message in the data plane (S1004). The present disclosure solves the problem that the time for the main ring node to process the sub-ring control message is too long during existing control message transmission process, avoids the control message loop situation caused by the transmission of the sub-ring control message over the main ring, and improves the network performance.

Abstract: An approach is provided for enabling fast network restoration. A node, within a network of multiple protocol label switching (MPLS) nodes, detects a failure condition affecting the node. A micro-loop with a neighboring node of the affected node is detected. A label is determined for a subsequent hop from the neighboring node to break the micro-loop for redirecting of traffic to a destination node in the network, wherein the subsequent hop does not create a loop with respect to the affected node.

Abstract: An optical ring network has one or more working wavelengths and multiple protection wavelengths adapted to support the working wavelength(s). Routing tables may be used in network nodes to assign traffic of a failed working wavelength to a protection wavelength. The protection technique may be applied to networks employing, for example, Dense Wave Division Multiplexing (DWDM).

Abstract: Precedence-based routing/rerouting algorithms or methods that work proactively and locally at each network node that engenders a collective restoral behavior that is uniquely rapid and anticipatory. The algorithms or methods are combined in a novel way with user precedence arbitration to provide superior performance in wireless dynamic ad hoc networks.

Abstract: In the case where an audio network system that performs transport of audio signals between a plurality of processors is constructed such that the plurality of processors each including two sets of transmission I/Fs and reception I/Fs are connected in series, and a TL frame generated by a master node is circulated along a ring transmission route formed among the processors in each fixed period, the TL frame including a plurality of storage regions for audio signals, when one of the processors is required to be the master node, the one processor resets in sequence processors which are connected on both sides thereof and processors behind the processors connected on both sides to once remove each of those processors from a ring transmission route if it belong to any ring transmission route, then incorporates the processors into a ring transmission route in which the one processor belongs to.

Abstract: According to embodiments of the invention, a first ring node is arranged to protect against loops in an Ethernet ring by performing Ethernet ring protection (ERP) according to an Ethernet ring protection protocol (ERP) standard. The first ring node is located directly adjacent to at least one second ring node in the Ethernet ring which is not configured to perform ERP according to the same ERP protocol standard. The first ring node is configured to, upon detection of a link failure or recovery event in the Ethernet ring resulting in a flush operation of the filtering database (FDB) in the first ring node in accordance with the ERP protocol standard, send a message to the at least one second ring node which is operable to cause said at least one second ring node to perform a flush operation of its filtering database (FDB). Embodiments of the invention also include an Ethernet ring, a broadband communications network and methods for use in the first ring node and in the Ethernet ring.

Abstract: A method includes obtaining information identifying one or more critical nodes and/or one or more critical links in a multi-hop network. Each critical node or critical link represents a node or link whose failure isolates at least part of the network. The method also includes generating a list identifying one or more orphaned nodes that lose connectivity to a gateway when a specified critical node or critical link fails. The list is generated using an Eigenvector of a matrix defining a topology of the network without the specified critical node or critical link. The method further includes identifying, using the list, at least one location where an additional node can be inserted into the network in order to reduce a number of is critical nodes and critical links in the network. The gateway and the orphaned node(s) can be associated with different values in the Eigenvector.

Abstract: A topology for routing message traffic between interconnecting nodes of a network is provided that includes a plurality of rings having a plurality of interconnecting nodes. A number of trees include at least one leaf at a same relative position of the rings. The trees and the rings form a unique combination that provides superior network performance for moderate numbers of the interconnecting nodes, wherein each interconnecting node has only a limited ability to handle a plurality of links.

Abstract: Systems and methods of automatically determining a set of route targets is provided. The method includes receiving network topology data specifying configuration of a network. The method also includes automatically converting the network topology data into route targets to be assigned to virtual routing and forwarding elements. The route targets are grouped into sets and duplicate sets of route targets are removed based on the route targets between duplicate sets of route targets identified as being the same. The method further includes generating a data record including information related to the set of route targets.

Abstract: The present invention relates to a method in an interface node for protecting an Ethernet ring from a superloop going through the Ethernet ring, wherein the Ethernet ring comprises a pair of interface nodes between the Ethernet ring and a VPLS-domain, the method comprising the steps of: receiving in the interface node a priority message indicating a priority level for each Ethernet ring connected to the VPLS-domain; receiving in the interface node a withdrawal message intended to indicate that the other interface node is malfunctioning; and transmitting from the interface node a signal failure message to the Ethernet ring in a case any other Ethernet rings has a lower priority level than said Ethernet ring.

Abstract: A method and system for maximizing wavelength reuse in an optically protected wavelength-division-multiplexed (WDM) network, the WDM network supporting a plurality of service connections, includes associating service connections supported by non-overlapping paths to form respective service channel groups, and for each service channel group, assigning at least one common wavelength channel for establishing the service connections. In addition, for each of said groups, at least one common wavelength channel is assigned for establishing a shared protection path for the service connections of each of said groups. In addition, the wavelength channels assigned for establishing the shared protection paths for each of the groups may be used for providing service connections for the WDM network when not in use as shared protection paths. However such provisional service connections are dropped when the wavelength channels are needed to establish shared protection paths.

Abstract: For a ring protection method in a packet transport network a failure is detected at a first network node (N4) in the ring (1, 2). The failure is communicated along the ring (1, 2) using an automatic protection switching protocol. At the first node (N4) or at a second node (N1) adjacent to the failure, a protection switch-over for at least one protected traffic stream (4) is activated by redirecting the traffic stream (4) into the reverse direction of the ring (1, 2). Selected network nodes (N2, N5) along the ring squelch the traffic stream (4) in accordance with pre-configured squelching tables. Squelching is performed only by networks nodes along the ring which perform either an add function or a drop & continue function for the traffic stream (4) to be squelched.

Abstract: Certain aspects of the invention for seamless port bypass controller operations for storage systems, for example, and may comprise a first port of a port bypass controller that receives an input signal and at least one of a plurality of selectors that selects at least a second port coupled in a chain to the first port. At least one of the selectors may switch at least a portion of the received input signal from the first port to at least the second port without initializing or reconfiguring the second port. A repeater may repeat at least a portion of the received input signal to the second port without initializing or reconfiguring the second port. A retimer may generate a retimed signal corresponding to at least a portion of the received input signal to the second port without initializing or reconfiguring the second port.

Abstract: A communication method and a master-slave system, for a field bus configures according to the AS-interface standard, are disclosed. Such a master-slave system for a field bus configured according to the AS-interface standard connects a master to a number of slaves. This field bus forms a first communication channel for the master and the slaves. In at least one embodiment, the master communicates with the slaves in sequence via telegrams, which are each uniquely associated with one of the slaves. Between the master and slaves a second communication channel is provided in at least one embodiment, via which one of the telegrams may be repeated, in addition to the first communication channel, if the communication of said telegram via the first communication channel has failed.

Abstract: Apparatuses, systems, and methods of routing data through an optical network are disclosed. One such method includes transmitting optical data via a first fiber optic network from an originating node on a first level to a second level, receiving the optical data at a destination node on a third level from the second level via a second fiber optic network, wherein the second level, connected to the first fiber optic network and the second fiber optic network, includes a first intermediate node as a primary route on the second level for transmitting the optical data from the originating node to the destination node, and a second intermediate node as an alternate route on the second level for transmitting the optical data from the originating node to the destination node when the first intermediate node fails.