Abstract: A data processing apparatus includes a receiving unit for receiving a packet, a determining unit for determining whether to process the packet data by a self-module, based on first information contained in the packet and indicating a processing order, a processing unit for processing the data if the data should be processed by the self-module, a generating unit for generating a packet containing the first information, and one of the processed data, and second information indicating that the data to be processed is stalled, and a transmitting unit for transmitting, according to the first information, the packet to a module expected to process the packet next. The transmitting unit performs the transmission at a transmission interval longer than a predetermined time, if the first and second information indicate that the packet contains data which should be processed by a module next to the self-module in processing order and is stalled.

Abstract: A term for interrupting communication caused by operation of a DFS function is reduced for a wireless communication apparatus having the DFS function and a wireless communication apparatus and a wireless communication system corresponding to the DFS function of the wireless communication apparatus. In the wireless communication apparatus and the wireless communication system having a frequency changing function for changing a using frequency upon detecting out-of-target electrical waves such as electrical waves of a weather radar on a specific using frequency, information about a connection destination having a different using frequency is notified upon detecting the out-of-target electrical waves, and the connection destination is changed by switching the frequency on the basis of the information about the connection destination.

Abstract: Delivering multicast data traffic over a communication network includes a first network node delivering multicast data traffic to second network nodes. The first and second network nodes are connected by a transmission network in a ring architecture and implement a point-to-multipoint layer 2 protocol. A method includes at the first network node: collecting alarms signals indicative of a failure along the whole ring and of the second network nodes. Based on a current state of the alarm signals, delivering the multicast data traffic either in a first delivery direction along the ring, or in a second delivery direction along the ring opposite to the first delivery direction, or in both the first and second delivery directions. At each of the second network nodes: collecting alarm signals indicative of a failure of the transmission network locally to the second network node and of the second network node.

Abstract: An encoder in a transmitter uses space-time trellis coding. An input bitstream is multiplexed to produce in parallel a set of output bitstreams. A multiplier applies a code generating weight to each output bitstream, which are combined, mapped and transmitted by a single antenna.

Abstract: A network device establishes first and second Ethernet link aggregation groups (LAGs) at a first access site of an optical transport network (OTN), and creates a first optical channel (OCh) LAG subpath from the first Ethernet LAG, via a second access site of the OTN, to an Ethernet LAG at a third access site of the OTN. The network device also creates a second OCh LAG subpath from the first Ethernet LAG, via a distribution site of the OTN, to the Ethernet LAG at the third access site, and creates a first optical data unit (ODUk) LAG subpath from the second Ethernet LAG to an Ethernet LAG at the second access site. The network device further creates a second ODUk LAG subpath from the second Ethernet LAG, via the distribution site and the third access site, to the Ethernet LAG at the second access site.

Abstract: A method, device, and system for establishing a label switching path (LSP) in fast rerouting (FRR) switching are provided, which can ensure that an ingress point and a merge point (MP) refresh path information in time. The method includes that first messages are respectively sent to an ingress point and an MP on an LSP, where the first messages carry information of holding a path refreshing state, so that the ingress point and MP determine the time of holding the path refreshing state according to the information of holding the path refreshing state; and second messages are respectively sent to the ingress point and the MP in the time of holding the path refreshing state, where the second messages carry information of refreshing a path state, so that the ingress point and MP establish the LSP according to the information of refreshing the path state.

Abstract: A method for updating a filtering database in a multi-ring network, includes: when the topology of a lower ring in a multi-ring network, in which a plurality of ring networks are connected by two ring connection nodes, is altered and the ring connection node detects the alteration in the topology of the lower ring, erasing, by the ring connection node, its filtering database; generating, by the ring connection node, a control message including a ring ID, a blockage flag, and an erasure flag; transmitting the control message in both directions of the ring; and determining, by a node which receives the control message, to erase a filtering database by referring to and correcting the blockage and erasure flag information included in the control message.

Abstract: Method and system for configuring a device that has failed to obtain a network address. In one aspect of the invention, a method for remotely configuring a device includes attempting to obtain a network address from a network server over a network, and receiving a valid network address over the network from a remote device connected to the network in response to failing to obtain the network address from the network server.

Abstract: According to one embodiment, allocating demand includes receiving a demand graph that describes demands of a network. One or more weights are calculated for each demand. The demands are allocated according to the weights of the demands to optimize optical line card sharing.

Abstract: A double ring network system configured with two or more transmission stations each including a pair of bi-directionally communicative communication ports, including any adjacent two transmission stations as terminal stations, and any transmission station as a base, as mutually connected in a ring form by communication ports through a transmission line, for intercommunications between transmission stations, in which the transmission stations are each adapted to determine whether or not frame signals are received from adjacent transmission stations, transmit route identifying frame signals for identification of routes to adjacent transmission stations, when having failed in reception, and set own station as a terminal station substituting for a current terminal station, when having received no responses to the route identifying frames from adjacent transmission stations, so they are kept from arriving at ring-like connected subsequent transmission stations.

Abstract: A system such as a “System-on-Chip” includes an interconnection network, a set of initiator modules for transmitting data towards the interconnection network and at least one communication arbiter for deciding, as a function of a set of configuration values, which transmissions of the initiator modules have access to the interconnection network. At least one configuration value is associated with each initiator module. A control device coupled to at least one of the initiator modules detects a communication status associated with the transmissions of the coupled initiator and generates a communication status signal whose value is representative of such status, determines a filtered value representative of a series of the values of the communication status signal, and selectively varies one of the configuration values as a function of the filtered value.

Abstract: An asynchronous communication network in an integrated circuit is described. The asynchronous communication network comprises a plurality of circuit elements enabling the transmission of tokens, each circuit element having a component interface comprising: a routing network coupled to a first adjacent circuit element of the plurality of circuit elements; and a control circuit coupled to the routing network, the control circuit having a first input coupled to receive a first command requesting a detection of a token received at a second input of the control circuit, and a first acknowledgement output coupling a first acknowledgement signal indicating whether the first command is received at the first input. Methods of enabling asynchronous communication in an integrated circuit are also disclosed.

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: An RTL hardware description language simulation accelerator and circuit emulator which operates on data driven asynchronous completion handshaking principles. Deploying Muller C elements to control latches, the system does not depend on externally provided clocks or internal timing circuits with delay logic or clock generators. Each levelized domain of logic signals a successor level to begin execution of instructions with a level complete message produced when all its input operands have produced a completion message. Each predecessor stage holds back data production until the successor stage is ready. Each levelized data-driven asynchronous domain evaluation processor is self-timed receiving completion messages from its predecessors, and sending completion messages to its successors.

Abstract: The present disclosure relates to a system comprising at least a first and a second essentially analogue portion and an essentially digital portion, the analogue portions forming a part of a unidirectional circular network. First communication means is provided between the digital portion and the first analogue portion. Second communication means is provided between the first and second analogue portions. The first and second communication means are configurable for establishing communication between the digital portion and the second analogue portion. The first and second communication means are arranged to determine if a packet communicated over the first or second communication means is of interest for any of the analogue portions.

Abstract: A communication node includes a token-start-right acquisition processor that issues a token-start-right acquisition frame containing specific information, determines a priority based on predetermined reference using specific information for other communication node and the specific information for the own communication node upon reception of a token-start-right acquisition frame from the other communication node, issues the token-start-right acquisition frame at a predetermined time interval when the own communication node has a higher priority than the other communication node, and stops issuing the token-start-right acquisition frame when the own communication node has a lower priority than the other communication node, to forward the token-start-right acquisition frame of the other communication node, and also includes a token start processor that passes the token frame to the ring upon reception of the token-start-right acquisition frame which is issued by the token-start-right acquisition processor and c

Abstract: Embodiments of the present invention automatically determine via heuristics optimal configurations to form sub-rings of nodes and where to position gateway processors among these sub-rings. The heuristics may be applied at a predefined timing interval configured by the user or in response to various events, such as a node failure or when a node joins the multi-ring network. Another embodiment of the invention may use automatic heuristics to determine when a suboptimal multi-ring configuration exists and formulates a new multi-ring configuration.

Abstract: A weighting process may be used to select between alternate neighbors in a RAPID calculation to enable policy and/or traffic engineering considerations to affect the selection of an alternate path through the network. The information used to weight the neighbors may static administratively assigned weighting information or dynamic weighting information such as local statistical traffic condition information. The process may take into account the amount of traffic being handled by the current primary next hop for the destination, the available capacity of the available alternate neighbors, the ability of the alternate neighbors to handle the additional traffic, and other considerations. Weighting may occur after a set of available loop free alternate neighbors has been determined. Alternatively, weighting may occur before the RAPID calculation has been performed to cause the neighbors to be ordered prior to RAPID processing. This may enable RAPID calculation to stop without considering all available neighbors.

Abstract: A method of merging Distributed Hash Table (DHT) rings in heterogeneous network domains, where each domain includes a DHT ring. Upon determining that a node is common to first and second DHT rings on the same hierarchical level and having at least one Overlay Router in common, a link is started between a node in the first DHT ring and a node in the second DHT ring by establishing an indirect link through the common node. An indirect link is created between the first and second DHT rings, and virtual links are created to DHT rings positioned higher in the DHT ring hierarchy until all the DHT rings are merged into a single logical ring.

Abstract: In general, this disclosure describes techniques that may allow detection of a missing control node on a ring network and selection of a single node on ring network to act as the control node. In one example, a method includes receiving, at a first node in a ring network, a data unit transmitted by a second node in the ring network, the data unit including an identifier that identifies the second node. The method further includes comparing the identifier of the second node to an identifier that identifies the first node, and automatically selecting one of the first node and the second node as a control node for the ring network based on the comparison.

Abstract: To enable an Ethernet ring to be dual homed into a spanning tree protocol controlled Ethernet network, spanning tree control packets (Bridged Protocol Data Units or BPDUs) are transported as data frames over the Ethernet ring. This allows the Ethernet ring to appear as a single link to the spanning tree protocol so that the spanning tree can extend over the link. However, since the spanning tree does not have visibility as to the internal structure of the ring, the spanning tree cannot block links on the Ethernet ring network. Conversely, BPDUs from the Ethernet ring are not transmitted into the Ethernet domain that is implementing the spanning tree, so that the spanning tree is not affected by the control mechanism in place on the Ethernet ring network.

Abstract: An information processing apparatus includes a plurality of modules connected in a ring shape via a bus, and each module processes a packet flowing in a single direction on the ring in a predetermined order. The module includes a communication unit for transmitting a packet received from a first direction in the ring via the bus to a second direction, a discrimination unit for discriminating a packet from among the packets received from the first direction as a processing packet to be processed by the module, and a processing unit which is connected with the communication unit one by one and configured to process the processing packet. The communication unit transmits the packet processed by the processing unit at an interval equivalent to processing time or more for a processing packet processed by a module in a latter stage in the predetermined order among packets transmitted by the communication unit to the second direction.

Abstract: According to a particular embodiment, a method for automatically assigning dynamic IP addresses without user interaction includes maintaining at least one pool of unused IP addresses. An advertisement message is transmitted from a first network element to at least one additional network element in a transport ring. The advertisement message identifies the first network element as providing IP address assignment services. The IP address request message from a second network element in the transport ring is received at the first network element. In response to the IP address request message, an IP address is dynamically assigned from the at least one pool of unused IP addresses. The dynamically assigned IP address is transmitted from the first network element to the second network element.

Abstract: A method run in a gateway for detecting a communication link between a called telephone and a telephone switch is provided. The method firstly detects if a ringer equivalency number (REN) is equal to zero. If the REN equals to 0, the method further determines if each discharge curve of a positive wire and a negative wire of the called telephone complies with a corresponding standard discharge curve, so as to determine if the communication link between the called telephone and the telephone switch has been established.

Abstract: In a multi-ring communication network, first and second rings include first and second connection nodes, respectively, that are adjacently connected to each other. The first connection node receives, from adjacent nods, traffic information storing a pair of input and output node identifiers in association with each of storage areas included in a frame to be transmitted, where the input node identifier identifies an adjacent node from which data is inputted, and the output node identifier identifies an adjacent node to which the data is outputted. When the received traffic information includes the output node identifier identifying the second connection node, the first connection node sets a plurality of redundant path segments each including the second connection node, based on the received traffic information, where the plurality of redundant path segments includes a currently-used path segment.

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: The invention provides a stacking system and a method for traffic switching in the stacking system, comprising: when newly joined devices in the stacking system make the daisy chain topology change to ring topology, block a stack port of one of the newly joined devices; after the devices in the stacking system perform another topology convergence process, the master restores the configuration of the newly joined devices; after the configuration of the newly joined device one of whose stack ports is blocked is restored, it sets its blocked stack port to the forwarding state, calculates the shortest path based on the ring topology, and sends first notification packets for topology change from daisy chain type to ring type through its two stack ports; each device that receives the first notification packets re-calculates its shortest forwarding path respectively and switches the traffic, and then forwards the first notification packets.

Abstract: A mobile backhaul inter-mesh communication point forms an interface between a wireless mesh network on a first level and a wireless mesh network on a second, higher bandwidth, level. The two wireless networks are differentiated, e.g., by causing the mesh networks to be formed using different spectra, protocols or coding, or antennae. The mobile intra-mesh communication point functions as an access point in the lower level mesh network and as a relay point in the upper level mesh network. Utilizing mobile inter-mesh communication points facilitates deployment of wireless network access points while enabling the location of access points to follow the concentration of network users. Mobile inter-mesh communication points may be deployed in personal vehicles such as cars, trucks, and motorcycles, public transportation vehicles such as busses, trains, and aircraft, emergency vehicles such as fire trucks and ambulances, and many other types of vehicles.

Abstract: Method and system for configuring a device that has failed to obtain a network address. In one aspect of the invention, a method for remotely configuring a device includes attempting to obtain a network address from a network server over a network, and receiving a valid network address over the network from a remote device connected to the network in response to failing to obtain the network address from the network server.

Abstract: Methods and apparatus for efficiently allowing protection switch information to be communicated on bidirectional lines are disclosed. According to one aspect of the present invention, a method for communicating protection switch information from a first network element to a second network element across bidirectional links that include at least one working line and a protection line involves obtaining a generic framing procedure GFP frame at the first network element. The GFP frame has a payload area with a client payload field. The method also includes defining a command field associated with the GFP frame that is in the payload area but not in the client payload field, and storing protection switch information in the command field.

Abstract: An apparatus comprising a chip comprising a plurality of nodes, a first plurality of links connecting the plurality of nodes in a first ring network having a first topology, and a second plurality of links connecting the plurality of nodes in a second ring network having a second topology, wherein the first topology is different than the second topology.

Abstract: A data communication system and an associated network node implementation is disclosed that, in certain embodiments, uses single-channel bi-directional communication links between nodes to send frames of data. The network nodes can be connected together in a ring or daisy chain topology with data frames sent in alternating directions through the bi-directional links. Such networks initially configured in a physical ring topology can tolerate single point failures by automatically switching to a logical daisy chain topology.

Abstract: With the advent of virtualization technologies, networks and routing for those networks can now be simulated using commodity hardware rather than actual routers. For example, virtualization technologies such as those provided by VMWare, XEN, or User-Mode Linux can be adapted to allow a single physical computing machine to be shared among multiple virtual networks by providing each virtual network user with one or more virtual machines hosted by the single physical computing machine, with each such virtual machine being a software simulation acting as a distinct logical computing system that provides users with the illusion that they are the sole operators and administrators of a given hardware computing resource. In addition, routing can be accomplished through software, providing additional routing flexibility to the virtual network in comparison with traditional routing. As a result, in some implementations, supplemental information other than packet information can be used to determine network routing.

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: A method for updating ring network topology information includes: receiving a topology discovery packet from an originating node, where the topology discovery packet at least carries identifiers of nodes traversed by the topology discovery packet when the packet is transferred from the originating node to a current node; and updating ring network topology information of the current node according to the identifiers of the nodes carried in the topology discovery packet. The apparatus includes a receiving module and an updating module. The system includes an originating node and a receiving node.

Abstract: A method and apparatus are provided for implementing system to system communication in a switchless non-InfiniBand (IB) compliant environment. IB architected multicast facilities are used to communicate between HCAs in a loop or string topology. Multiple HCAs in the network subscribe to a predetermined multicast address. Multicast messages sent by one HCA destined to the pre-determined multicast address are received by other HCAs in the network. Intermediate TCA hardware, per IB architected multicast support, forward the multicast messages on via hardware facilities, which do not require invocation of software facilities thereby providing performance efficiencies. The messages flow until picked up by an HCA on the network. Architected higher level IB connections, such as IB supported Reliable Connections (RCs) are established using the multicast message flow, eliminating the need for an IB Subnet Manager (SM).

Abstract: In order to provide a bus guardian (30) for monitoring communication between and among a number of nodes (100), in particular between and among a number of electronic control units, the bus guardian (30) being designed for monitoring at least one cyclic time-triggered communication media access schedule for transmitting messages between and among the nodes (100) across at least one communication media (10), in particular across at least one channel (12) and across at least one optional further channel (14), and being assigned to at least one communication controller (40), the communication controller (40) comprising the communication media access schedule, wherein the bus guardian (30) as well as a corresponding method require neither any a priori knowledge of the communication schedule nor any configuration parameter and monitor the communication media access schedule of the communication controller (40) even during start-up of the communication, it is proposed that that the bus guardian (30) is able to lear

Abstract: A hub-free network system is provided in which control systems can operate normally for mutual communications, even though one of the plurality of control systems malfunctions. Each of the plurality of control systems has a network interface card, and each of the network interface cards has a plurality of communication ports. Each of the network interface cards has a phase structure of ring topology by sequentially connecting a plurality of the communication ports. The plurality of the control systems perform the communications in the phase structure of ring topology, and perform the communications by changing the phase structure of ring topology to a phase structure of bus topology if an error occurs in the communications.

Abstract: A communication node includes a token-start-right acquisition processor that issues a token-start-right acquisition frame containing specific information, determines a priority based on predetermined reference using specific information for other communication node and the specific information for the own communication node upon reception of a token-start-right acquisition frame from the other communication node, issues the token-start-right acquisition frame at a predetermined time interval when the own communication node has a higher priority than the other communication node, and stops issuing the token-start-right acquisition frame when the own communication node has a lower priority than the other communication node, to forward the token-start-right acquisition frame of the other communication node, and also includes a token start processor that passes the token frame to the ring upon reception of the token-start-right acquisition frame which is issued by the token-start-right acquisition processor and c

Abstract: A telecommunication network includes a communication ring having a plurality of nodes. The communication ring includes a plurality of links wherein each link interconnects one node to another node. Each node includes one or more network elements. Management functions for the nodes, the communication ring, the links, and the network elements are provided by a manager. The manager can discover and define the nodes, the links, and the communication ring and establish more than one network element at a node. The manager provides a coherent view of the telecommunication network despite a node being supported by more than one network element.

Abstract: According to one embodiment, in a double-ring network, a master station includes a transmitting and receiving permission switch portion, a communication port A at an A-system side, a communication port B at a B-system side, a first receiving control circuit portion, a transmitting and receiving control circuit portion, a frame detection determining circuit portion, a frame data generating circuit portion, a logical address determining circuit portion, a live list setting circuit portion and an address list setting circuit portion. The master station determines a token order (a transmission priority, also called a logical address) using a shortest path function by the logical address determining circuit portion and the address list setting circuit portion such that the token order does not depend on physical addresses of transmission stations and is matched to a connection order of transmission stations to realize path optimization. This reduces a transmission time.

Abstract: Methods, systems and data structure for facilitating identification of nodes in a ring network are provided. According to one embodiment, a data structure is stored on a computer-readable storage media of a node (e.g., a blade) participating in a ring network, within a multi-blade system, for example. The data structure includes a packet-ring master field, a control-node master field, a node characteristics field, a connection state field, a node identification field and a marker field. The packet-ring master field indicates whether the node is a current packet-ring master. The control-node master field indicates whether the node is a control-node master. The node characteristics field specifies per-node characteristics. The connection state field indicates a current connection state of the node. The node identification field specifies the node. The marker field indicates whether the data structure is a node discovery marker.

Abstract: A path setting method for setting a backup path corresponding to a currently used path in a ring network using a label switching method includes setting an unused first label as a transmitting label of the backup path corresponding to the currently used path in a first direction; reporting the first label to a adjoining transmission device in the first direction; setting the first label as a receiving label of the backup path in the first direction; setting an unused second label as the transmitting label of the backup path in a second direction; reporting the second label to a adjoining transmission device in the second direction; and setting the second label as the receiving label of the backup path in the second direction, in which the backup path is set when the currently used path is set between two transmission devices.

Abstract: A distributed messaging system and method allows servers in a network to share data, such as network status data associated with all of the servers in the network. In one embodiment, the distributed messaging system and method may be used in element management system (EMS) servers in a distributed network management system (NMS). The servers in the network share the data in a distributed manner by transmitting messages including the network status data, for example, using a star/broadcast method or a circular message queue (CMQ) method.

Abstract: A data communication system and an associated network node implementation is disclosed that, in certain embodiments, uses single-channel bi-directional communication links between nodes to send frames of data. The network nodes can be connected together in a ring or daisy chain topology with data frames sent in alternating directions through the bi-directional links. Such networks initially configured in a physical ring topology can tolerate single point failures by automatically switching to a logical daisy chain topology.

Abstract: Various systems and methods for integrating ring-protocol-compatible devices into network configurations that also include non-ring-protocol-compatible devices are disclosed. One such method, which can be performed by a network node that supports a ring protocol, involves generating a ring protocol packet and sending that ring protocol packet to a neighboring node. The ring protocol packet includes information, and the presence of this information within the packet causes a network device that receives the ring protocol packet to drop the ring protocol packet unless the network device supports a ring protocol. The information can include a reserved address (e.g., in the destination address field of the packet) as well as a ring protocol identifier.

Abstract: A communication management apparatus that manages transmission of data in a network in which plural communication nodes are connected via a transmission line in a ring shape, the apparatus including: a network-presence checking unit that transmits a network-presence-check frame in broadcast and generates network connection information indicating a connection state among the connection nodes from a received network-presence-check acknowledge frame, a token-circulation-order determining unit that determines token circulation order; a setup processing unit that performs setup processing for notifying each of the communication nodes of a token circulation destination; a data-frame-communication processing unit that performs transmission and reception of a data frame using a token frame; and a line-connection managing unit that disables, when the network has a ring configuration, any one of ports of any one of the communication nodes to prevent a connection state of the network from becoming a ring shape.

Abstract: The present invention discloses a method for refreshing a single ring address of an Ethernet ring, which method comprises: achieving address refresh on an on-ring port at one side of a same node by the control of a refresh timer. The present invention further discloses a system for refreshing a single ring address of an Ethernet ring, which system comprises: an address refresh achieving unit configured to achieve address refresh on an on-ring port at one side of a same node by the control of a refresh timer. The method and system of the present invention reduces the number of refreshes of the address forwarding table and improves the efficiency and stability of Ethernet ring protection, thus greatly promoting the performance of the Ethernet ring.

Abstract: A method may be performed by a device in a network, the device including multiple security process units (SPUs). The method includes receiving a packet over the network, the packet including a media access control (MAC) address, and assigning one SPU as the MAC address owner. The method also includes sending information about the MAC address to other SPUs within the device, storing the MAC address in a MAC table within each SPU, and initiating a MAC age query to confirm the MAC address has timed out among all SPUs. The MAC age query is passed via a logical ring of the SPUs beginning with the MAC address owner. If the MAC address is aged out at each SPU, the MAC address is deleted from each MAC table. If the MAC entry is still active, a different SPU is assigned as the MAC address owner.

Abstract: A method automatically discovers a topology of a communication network ring. The ring includes a plurality of nodes. Each node includes a first port and a second port. A ring topology request or a response to the ring topology request is received from at least one node on the ring. The ring topology request or the response to the ring topology request includes an identification of the at least one node and an indication of a hop count needed to reach the at least one node. The ring topology request or the response to the ring topology request is forwarded to at least one neighboring node on the ring through the first port. The topology is determined based on the identification of the at least one node, the hop count, and an identification of the first port.