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Packet switching system or element

Subclass of:

370 - Multiplex communications

370216000 - FAULT RECOVERY

370217000 - Bypass an inoperative switch or inoperative element of a switching system

Patent class list (only not empty are listed)

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Class / Patent application numberDescriptionNumber of patent applications / Date published
370219000 Standby switch 41
20130044586FASTER FAILOVERS FOR FAST REROUTE (FRR) LSPs - Techniques for reducing the latency in performing a failover from a protected connection to its backup connection when a network event is detected affecting the protected connection. In an MPLS network, techniques are provided for failing a protected LSP to a backup LSP in a fast and efficient manner. In one embodiment, the faster failover is facilitated by storing protected LSPs and their backup LSPs information in the data plane, such as locally on a linecard.02-21-2013
20130028073Controller Placement for Fast Failover in the Split Architecture - A method implemented by a network topology design system, the network topology design system including a processing device. The method to determine placement of a controller within a network with a split architecture where control plane components of the split architecture network are executed by a controller and the control plane components are separate from data plane components of the split architecture network. The placement of the controller is selected to minimize disruption of the split architecture network caused by a link failure, a switch failure or a connectivity loss between the controller and the data plane components01-31-2013
20130028074METHOD AND APPARATUS FOR PROTECTING A COMMUNICATION NETWORK AGAINST FAILURE - A method for protecting a communication network against failure, comprising the steps of: a) obtaining a primary network, represented by a graph of nodes and links, wherein each link has an associated capacity; b) computing a backup network, that includes nodes of the primary network and links that are not in the primary network; c) when a link of the primary network fails, rerouting communication traffic, through one or more links of the backup network, in order to bypass the failed link. Methods are suggested to determine the backup network, one method relates to expressing the objective and constraints on the backup network as linear or integer expressions, and a linear or integer programming tool is used to solve the equation system and provide optimal backup network.01-31-2013
20130028072METHOD AND SYSTEM FOR MANAGEMENT OF FLOOD TRAFFIC OVER MULTIPLE 0:N LINK AGGREGATION GROUPS - In accordance with embodiments of the present disclosure, a method and system may include receiving a plurality of packets comprising flood traffic of a bridged VLAN domain at an ingress line card port. The system and method may further include splitting the packets into multiple internal streams and forwarding the packets associated with the internal streams to a switch fabric. The system and method may further include forwarding each packet associated with a particular internal stream to one or more egress line cards associated with the internal stream. The system and method may further include mapping each internal stream to a single egress port of the egress line card, the single egress port comprising one of a plurality of egress ports associated with a LAG. The system and method may further include recovery from a port failure.01-31-2013
20110194404SYSTEM AND METHOD FOR FAST PROTECTION OF DUAL-HOMED VIRTUAL PRIVATE LAN SERVICE (VPLS) SPOKES - A novel and useful system and method for fast protection of dual homed Virtual Private LAN Service (VPLS) spokes. Fast protection is achieved by forwarding traffic to the dual homed VPLS spoke from the VSI that is not currently the one currently serving it, as long as the traffic is known unicast. Egress traffic at the VSI that does not currently serve the VPLS-spoke is re-routed over a protection transport entity to the VPLS-spoke through the device of the VSI currently serving it. Broadcast, multicast and unknown (BMU) traffic is sent to the VPLS spoke only by the BMU-primary VSI. BMU frames received at the BMU-secondary VSI are dropped. A fast election process serves to elect the BMU-primary for coordinating between the two VSIs serving the same VPLS spoke. In addition, a flag is inserted in each frame at an ingress VSI to indicate whether the frame is known or unknown unicast. Unknown unicast frames are forwarded to the VPLS spoke only by the BMU-primary.08-11-2011
20090109840Fault-resistant digital-content-stream AV packet switch - An AV packet switch comprises a multiplexer system having multiple multiplexer input terminals and multiple multiplexer output terminals, a particular multiplexer input terminal capable to receive an input stream synchronized with a first clock signal, a particular multiplexer output terminal capable to receive the input stream from the particular multiplexer input terminal; and an output stream destination synchronizer coupled to the particular switch output terminal capable to synchronize the input stream with a destination's clock signal.04-30-2009
20130077470Method For Applying Macro-Controls Onto IP Networks Using Intelligent Route Indexing - Systems and methods are described that manage routing information in an IP network using extensible indexing and use the indexing to control the network. The indexing and associated controls apply to any router within the routing domain.03-28-2013
20130083650METHOD FOR HANDLING FAILURE OF A MME IN A LTE/EPC NETWORK - Method for handling failure of a MME (Mobility Management Entity) in a Long Term Evolution/Evolved Packet Core network or an Evolved Packet System, wherein multiple UEs (User Equipment) are attached to a first MME, which stores first context information representing the UEs attached to the first MME, the UEs are connected to one of multiple eNBs (evolved NodeB), the eNB may communicate with the first MME and with at least one neighboring MME, and the UEs may communicate with the first MME and with the at least one neighboring MME via the eNB, includes: detecting failure of the first MME, gathering information related to UEs attached to the first MME, restoring parts of the first context information at one or several of the neighboring MME using the gathered information, and re-establishing network internal logical connections with the one or several of the neighboring MME using the restored first context information.04-04-2013
20130051218SYSTEM AND METHOD FOR ASSURING THE OPERATION OF NETWORK DEVICES IN BRIDGED NETWORKS - In one embodiment, a spanning tree protocol (STP) is executed to assign a first port of an intermediate network device to a Root Port Role, a second port of the intermediate network device to an Alternate Port Role, a third port of the intermediate network device to a Designated Port Role, and a fourth port of the intermediate network device to a Backup Port Role. At least one bridge protocol data unit (BPDU) message is periodically sent from the first port assigned Root Port Role, the second port assigned Alternate Port Role and the fourth port assigned Backup Port Role, irrespective of receipt of any BPDU messages from neighboring intermediate network devices. In response to a failure to receive a BPDU message from a neighboring intermediate network device on the third port assigned Designated Port Role within a threshold amount of time, one or more actions are taken.02-28-2013
20130088953Failure Detection in the Multiprotocol Label Switching Multicast Label Switched Path's End-to-End Protection Solution - In one aspect, the invention includes, in a root node along a secondary label switching path, a computer program product comprising computer executable instructions stored on a non-transitory medium that when executed by a processor cause the root node to perform the following: establish a first data plane based failure detection session having an inactive status along a first label switching path (LSP) with at least one leaf node, receive a predetermined number of notification messages from the leaf node, wherein the predetermined number of notification messages indicate the failure of a second data plane based failure detection session along a second LSP from a second processor to the leaf node, and change the status of the first data plane based failure detection session to active along the first LSP upon receipt of the predetermined number of notification messages.04-11-2013
20120307623Method and Apparatus Providing Selective Flow Redistribution Across Multi Link Trunk/Link Aggregation Group (MLT/LAG) After Port Member Failure and Recovery - A method, apparatus and computer program product are presented. In a system having at least one Multi Link Trunk/Link Aggregation Group (MLT/LAG), a table is provided for each MLT/LAG, each table having at least one entry, each entry including at least two fields, a first field comprising a port member identification (ID) field and a second field comprising a port member status field. A port member status is checked for a port when a packet flow hashes into the table, and the status for the port member is determined. When the port member status is in a first state, then the associated port member ID is used as a destination port to transmit to. When the port member state is in a second state, then a next entry in the port table is accessed to find a next available entry having a port member status that is in the first state and the corresponding port member ID of the port member state that is in the first state is used as a destination port to transmit to. The first state is UP and the second state is DOWN.12-06-2012
20080225698Controlling multicast source selection in an anycast source audio/video network - Particular embodiments of the disclosed subject matter provide methods and systems to support a multicast source selection system. In an example embodiment, the system includes a network element in data communication with a network, the network element being operable to: receive a request for withdrawal of a server as a source of a multicast data stream; and propagate information to the network indicating withdrawal of the server as a source of the multicast data stream, the propagation of information by the network element being responsive to the request for withdrawal of the server as a source of the multicast data stream.09-18-2008
20130064067HIGH AVAILABILITY DISTRIBUTED FABRIC PROTOCOL (DFP) SWITCHING NETWORK ARCHITECTURE - In a switching network, each of a plurality of lower tier entities is coupled to each of multiple master switches at an upper tier by a respective one of multiple links. At each of the multiple master switches, a plurality of virtual ports each corresponding to a respective one of a plurality of remote physical interfaces (RPIs) at the lower tier are implemented on each of a plurality of ports. Each of the plurality of lower tier entities implements a respective egress port mapping indicating which of its plurality of RPIs transmits egress data traffic through each of its multiple links to the multiple master switches. In response to failure of one of the multiple links coupling a particular lower tier entity to a particular master switch, the particular lower tier entity updates its egress port mapping to redirect egress data traffic to another of the multiple master switches without packet dropping.03-14-2013
20090109841Layer-2 Redundancy Protocol Interconnection Device - Interconnection devices and interconnect a network running a redundancy protocol and another network running a redundancy protocol. The interconnection devices controls the redundancy protocol of a lower level network via virtual ports and by a virtual link, to redundancy-connect the lower level network to a higher level network. When a communication route of the lower level network is changed, MAC address learning results of the higher level network are cleared to perform switching of communication routes at high speed.04-30-2009
20090268607METHOD AND DEVICE FOR MULTICAST TRAFFIC REDUNDANCY PROTECTION - A method and apparatus of multicast traffic redundancy protection is provided. After a fault occurs, the VRRP selects a new active router and notifies the PIM routing protocol, and the PIM uses the new active router as its DR.10-29-2009
20110299385NO SPLIT VIRTUAL CHASSIS BASED ON PASS THROUGH MODE - A method includes operating in a normal mode to receive and transmit packets, where the network device is one of multiple network devices that operate as a virtual chassis, where the virtual chassis corresponds to a single logical network device, and detecting when the network device crashes. The method further includes initiating a resetting process and operating in a pass through mode, during the resetting process, where the pass through mode permits packets to be received and transmitted to the network devices of the virtual chassis.12-08-2011
20110292788FRAME DATA COMMUNICATION - A switch node stores reception connection information for identifying the connection of frame data that are received in association with transmission connection information for identifying the connection to which the frame data are to be transmitted, and upon receiving frame data, searches for the transmission connection information that was placed in association with the reception connection information of the frame data that were received and distributes and transmits the frame data to the connection of the transmission connection information that was found.12-01-2011
20100302935METHOD AND SYSTEM FOR RESILIENT ROUTING RECONFIGURATION - A method and system for resilient routing reconfiguration, which provides provably congestion-free rerouting under a large number of failure scenarios and achieves efficiency and flexibility in accommodating different performance requirements, is disclosed. The method of embodiments comprises an offline precomputation phase and an online reconfiguration phase. Embodiments of the present invention also provide a number of useful functionalities, including (i) coping with traffic variations, (ii) supporting realistic failure scenarios, (iii) accommodating prioritized traffic with different protection levels, and (iv) balancing the trade-off between performance and resilience.12-02-2010
20090196169METHODS AND APPARATUSES FOR PROCESSING AND MANAGING SUBSCRIBER DATA IN TELECOMMUNICATION NETWORK - In order to overcome the defects of the centralized subscriber data management in the telecommunication network, a highly effective distributed data management system for the communication network is achieved in the present invention through improving and applying the distributed Hash table (DHT) technology to subscriber data management in the communication network, which overcomes the deficiencies of the conventional centralized data management. A method for processing subscriber data in a communication network based on a DHT is provided, which includes the following steps. A first node in a DHT overlay network receives subscriber data to be stored. The subscriber data to be stored is regarded as backup data divided into L/K portions. L is greater than or equal to a ratio of a node working bandwidth of a second node to a node recovering bandwidth for data recovery of the second node in the DHT overlay network. K is a total number of backup data and is an integer greater than zero. The subscriber data to be stored is regarded as master data, and the master data and K×L/K divided backup data are, respectively, stored in 1+K×L/K DHT nodes.08-06-2009
20090185481METHOD AND NETWORK NODE FOR SELF-REGULATING, AUTONOMOUS AND DECENTRALIZED TRAFFIC DISTRIBUTION IN A MULTIPATH NETWORK - According to one embodiment, traffic load is redirected in reaction to traffic overload or a link failure in a packet-based network that is formed by nodes and links, packets being distributed along multiple paths to other links of an associated array of paths. The redistribution is performed autonomously by the node which is located immediately upstream of the affected link. According to a further development of the method, nodes that are located upstream of the concerned node are notified and are made to perform a redistribution that relieves the concerned node if the array of paths is not made overload-free by the redistribution performed by the node. A mechanism that protects against overload and failures and reacts in a significantly more flexible and less error-prone manner than networks having a central control body due to the nodes being autonomous is provided.07-23-2009
20100103813PROVISIONED PROVIDER LINK STATE BRIDGING (PLSB) WITH ROUTED BACK-UP - A method of managing traffic flow in a packet network. A working sub-network is provided, which comprises one or more provisioned static working paths between at least one source node and one or more destination nodes in the network, and the working sub-network with a service instance. A backup sub-network is provided, which comprises one or more dynamic protection paths between the at least one source node and the one or more destination nodes, and the backup sub-network associated with the service instance. During a normal operation of the network, forwarding subscriber traffic associated with the service instance through the network using the working sub-network. Following detection of a network failure affecting the service instance, the subscriber traffic associated with the service instance is switched for forwarding through the network using the backup sub-network.04-29-2010
20090185482METHOD AND SYSTEM FOR PROTECTION SWITCHING DECISION - A method for protection switching decision includes: performing performance monitoring and failure detection on a first transmitting entity that transmits services; performing performance monitoring and failure detection on a second transmitting entity that does not transmit services; and making protection switching decision according to the performance monitoring and failure detection results of the first transmitting entity and second transmitting entity. A system for performance monitoring is also disclosed. In embodiments of the present invention, performance monitoring may be performed on the transmitting entity that does not transmit services, thus avoiding invalid switching of services and improving the quality of services.07-23-2009
20100085869METHOD AND APPARATUS FOR MAINTAINING NETWORK PERFORMANCE IN A COMMUNICATION SYSTEM - A method and apparatus is disclosed for method and apparatus for maintaining network performance in a communication system. A system that incorporates teachings of the present disclosure may include, for example, a network management server (NMS) that manages operations of a communication system including an access office (AO) coupled to a plurality of base terminals (BTs) by way of a corresponding plurality of network elements. The NMS can have a network configuration element that identifies for each of the plurality of BTs a plurality of resultant communication paths to the AO according to a plurality of differential delays calculated from alternative communication paths connecting combinations of the BTs to the AO for each of a plurality of change scenarios affecting the plurality of network elements, wherein the network configuration element arranges portions of the plurality of BTs into a corresponding plurality of groups, and selects for each BT in a select one of the plurality of groups its corresponding plurality of resultant communication paths to the AO according to differential delays calculated for alternative communication paths associated with combinations of BTs in the selected group and the plurality of change scenarios affecting the selected group. Additional embodiments are disclosed.04-08-2010
20110199892GMPLS FAST RE-ROUTE FOR OADM AND AUX 10MBPS SUPPORT - Embodiments of the present invention provide a GMPLS fast re-route of packets within a network using a multicast address and a table comprising a list of alias IP addresses. According to various embodiments of the invention an alternate data path from a source node to a destination node allows a packet to traverse to the destination node without IP forwarding techniques being applied. In other words, a tunneling effect from a source node to a destination node allows other nodes in the network to ignore the packet and only read the multicast address within the header and immediately forward the packet to the destination node. A predetermined set of IP addresses are determined from network topology including all potential paths, for a packet to traverse, to a destination address.08-18-2011
20110199891System and Method for Protecting Ingress and Egress of a Point-to-Multipoint Label Switched Path - A network comprising a first edge node, a second edge node, a third edge node that backs up either the first edge node or the second edge node, and an internal node coupled to the first edge node, the second edge node, and the third edge node, wherein a point-to-multipoint (P2MP) label switched path (LSP) extends across the network from the first edge node, through the internal node, and to the second edge node, and wherein a LSP sub-tree extends between the third edge node and the internal node, but does not extend across the network.08-18-2011
20090168642TELEPHONE SYSTEM, AND NODE DEVICE AND REROUTING METHOD FOR THE SYSTEM - According to one embodiment of the invention, there is provided a telephone system comprises nodes connected to a first network of a packet exchange type and a second network of a volume-based charging type. The nodes mutually form a communication route. The system comprises terminal devices each connected to any one of the nodes and configured to mutually perform telephone communication via the route. Each of the nodes comprises a detector monitors a state of first network to detect failure in the first network, a reroute processor reroutes a part of the route into second network via a relay node to be an interface between the networks to avoid the detected failure, and a decision processor decides a relay node to minimize a cost required for the route to pass the second network. The reroute processor reroutes the route via the relay node decided by the decision processor.07-02-2009
20090154340FAST OSPF INACTIVE ROUTER DETECTION - A fast OSPF inactive router detection technique is provided that detects the failure of a router and switches routing to an alternate router. The alternate router provides a message to the other routers in the Wide Area Network (LAN) that informs of the router failure.06-18-2009
20090086621Correlating Label Switched Paths Of A Pseudowire - In one embodiment, correlating label switched paths of a pseudowire includes receiving a first message at a second label switching router. The first message is sent from a first label switching router and includes a pseudowire identifier and a first label switched path identifier. The pseudowire identifier identifies a pseudowire, and the first label switched path identifier identifies a first label switched path that implements the pseudowire. A second message is sent from the second label switching router to the first label switching router. The second message comprises the pseudowire identifier and a second label switched path identifier. The second label switched path identifier identifies a second label switched path that implements the pseudowire.04-02-2009
20090285089Method and Apparatus for Validating Control and Data Plane Association - A method and apparatus for validating control and data plane association is described. In one embodiment of the invention, a first provider edge (PE) network element negotiates a pseudowire with a second PE network element. The pseudowire is uniquely identifiable between the first and second PE network element with a unique pseudowire identifier. The first PE network element receives OAM (operations, administration, and management) packets each including a pseudowire identifier from the second PE network element over the negotiated pseudowire. If an OAM packet is received with a pseudowire identifier that does not match the negotiated pseudowire, the first PE network element determines a data plane fault is associated with the pseudowire on the second PE network element. However, if the OAM packets include the pseudowire identifier that matches the negotiated pseudowire, the control and data plane association of the second PE network element is validated. Other methods and apparatuses are also described.11-19-2009
20090279426SYSTEM AND METHOD FOR DEAD GATEWAY DETECTION - A system and method for detecting a next-hop dead gateway is disclosed. In one embodiment, a method for detecting the next-hop dead gateway includes sending an Internet Protocol (IP) packet by a host to a next-hop gateway associated with the host, receiving the IP packet by the host from the next-hop gateway upon reviewing a routing table and the destination field in the IP header associated with the IP packet, determining whether the IP packet is received from the next-hop gateway within a first predetermined time interval, if so, declaring the next-hop gateway as alive, and if not, declaring the next-hop gateway as dead. In some embodiments, source and destination fields in IP header associated with the IP packet include IP address associated with the host. The method may further include encapsulating the IP packet with a data link layer protocol associated with the host and the next-hop gateway.11-12-2009
20120294141METHOD FOR IMPLEMENTING PROTECTION GROUP OVERLAY, AND METHOD AND SYSTEM FOR ETHERNET PROTECTION SWITCHING - This disclosure discloses a method for implementing protection group overlay and a method for implementing Ethernet protection switching based on the protection group overlay. The method for implementing Ethernet protection switching based on the protection group overlay comprises: when the fault of TESI is detected by multiple IPG which protect the same TESI, only one IPG of the multiple nested IPGs performs protection switching. This disclosure further discloses a system for implementing Ethernet protection switching based on the protection group overlay, comprising a protection switching performing unit, configured to when a fault of a TESI is detected by multiple IPGs which protect the TESI, only one IPG of the multiple nested IPGs performing protection switching. Application of the method and system of this disclosure implements protection for key protected path through protection group overlay, and can achieve effects of saving network resource and increasing utilization rate of network resource.11-22-2012
20090109839Apparatus for Realizing Soft-Switch Allopatric Disaster Recovery Based on Packet Network - The present invention provides a device for realizing disaster recovery of soft-switch based on packet network, comprising at least two core control devices located in different places which provide control service for their respective access equipments; wherein said core control devices further include a process unit, a database unit, a share unit and a synchronization process unit which are specifically used for remote disaster recovery; said process unit and database unit are independent of the processor and the database already existing within the core control devices, and are specifically used for providing service for remote access equipments, thereby making the core control devices in different places be of mutual disaster recovery relation; said share unit is used for sharing processing ability and data; and said synchronization process unit is used for synchronizing data between the core control devices of mutual disaster recovery. The core control devices capable of providing disaster recovery function of the present invention guarantee uninterrupted operation for system, and provide high accessability of the access equipments in the packet switch network.04-30-2009
20080273455Retry Strategies for Use in a Streaming Environment - Strategies are described for performing retry analysis in an environment which involves the transmission of media information from a source module to a target module. In the context of the source module, the retry analysis determines whether the source module should satisfy the retry requests issued by the target module. In the context of the target module, the retry analysis determines whether the target module should generate the retry requests in the first place. Novel request reporting formats are also described. The target module performs analysis to determine what reporting format it should use to convey the retry requests to the source module.11-06-2008
20090161533ACTIVE FAULT MANAGEMENT FOR METRO ETHERNET SERVICE OVER MPLS NETWORK - In one embodiment, a technique for detecting a break in a pseudowire and automatic shutting down user network interface (UNI) ports affected by the break is provided. In response to the loss of connectivity on the shut down ports, customer edge devices may automatically switch over to redundant circuits (e.g., other UNI ports not affected by the break in the pseudowire) and establish a different pseudowire.06-25-2009
20090185480Method and System for Re-enabling Disabled Ports in a Network with Two Port MAC Relays - A system and method for enabling a disabled port on a device such as a Two Port Medium Access Control (MAC) Relay (TPMR), which relays MAC frames in a communication network. When a link in the network fails, the TPMR disables the port due to operation of a link failure propagation protocol. When the TPMR detects that the failed link is repaired, the TPMR stops transmitting link failure Packet Data Units (PDUs) and transmits a Link Failure Terminating PDU to other connected TPMRs in the network. Receipt of the Link Failure Terminating PDU indicates the failed link is repaired and all ports disabled as a result of the failure should consequently be enabled.07-23-2009
20120069730SYSTEM AND METHOD FOR SUPPORTING MANAGEMENT NETWORK INTERFACE CARD PORT FAILOVER IN A MIDDLEWARE MACHINE ENVIRONMENT - A system and method can support virtual network interface card (NIC) failover in a middleware machine environment. The middleware machine environment includes a local management node and a remote management node. The system provides a local NIC driver and a remote proxy instance on a local management node. The remote proxy instance can associate a machine address with a remote NIC driver on a remote management node that is connected with the local remote management node in a subnet. Furthermore, the remote proxy instance operates to direct packets to and from the remote NIC driver using the machine address.03-22-2012
20090003194Resilience Solution for Top Tier Bandwidth Managers - The present invention relates to a back up top tier bandwidth manager (01-01-2009
20090003195INTELLIGENT NETWORK RESTORATION - A device may isolate a first failure of a network interface that transports packets from one point in a network to another point in the network, may detect a subsequent failure of the interface, and may identify a recovery of the network interface from the subsequent failure. In addition, the device may restore the network interface to the network to enable the interface to transport packets after a wait-to-restore period that is approximately greater than or equal to a time difference between when the first failure and the subsequent failure occur.01-01-2009
20130182559TRANSMISSION NETWORK AND TRANSMISSION NETWORK MANAGEMENT SYSTEM - A transmission network is comprised of a network management system for collectively managing and controlling a plurality of transmission devices coupled mutually through transmission routes and the transmission network as well. The network management system includes a plane management table adapted to manage transmission planes defined as a set of paths in the transmission network, and the plane management table has the function to set and manage a transmission plane (working plane) applied during normal operation and besides, a single or a plurality of transmission planes (protection planes) applicable in the event of occurrence of a fault in the transmission network. Then, when a fault occurs in the transmission network, the network management system changes the applied plane to a suitable transmission plane.07-18-2013
20090185479Communication Systems - An uplink transmission method for use in a multi-hop communication system, the system comprising a mobile station (MS), a base station (BS) and one or more relay stations (RS), and the system providing two or more different communication paths extending between the mobile station and the base station, the mobile station being operable to transmit information indirectly to the base station along a series of links forming a first such communication path via one or more of the relay stations and also being operable to transmit information to the base station along one link or a series of links forming a second such communication path; the method comprising transmitting particular information from the mobile station along the first and the second communication paths; and combining the same particular information transmitted along the first and second communication paths in the base station.07-23-2009
20090219804ROUTING PROTOCOLS FOR ACCOMMODATING NODES WITH REDUNDANT ROUTING FACILITIES - Graceful restart in routers having redundant routing facilities may be accomplished by replicating network (state/topology) information.09-03-2009
20080259786SYSTEM AND METHOD FOR SUPPORTING SDH/SONET APS ON ETHERNET - An Ethernet PHY hardware device supports Ethernet MAC SDH/SONET Automatic Protection Switching (APS) functionality for managing protection from failures and recovery from failures on an Ethernet network. An Ethernet PHY sublayer stored on the Ethernet PHY hardware device is configured to monitor working and protect channels and generate an interrupt upon detection of a hard failure or a soft failure. Upon detection of port failures or link failures, the Ethernet PHY sublayer generates the interrupt to invoke an Ethernet MAC Client APS Controller configured to generate and terminate APS requests on working and protect channels to manage protection of working and protect channels from failures and recovery from failures on the Ethernet network. The Ethernet PHY hardware device is configurable for use with a plurality of different network topologies to manage protection from hard or soft failures and recovery from hard or soft failures on the Ethernet network using the Ethernet PHY sublayer.10-23-2008
20090316571Loop Prevention Mechanism for Ethernet Ring Protection - A node (bridge, switch, router) and method are described herein that implement a loop prevention mechanism for Ethernet ring protection. In one embodiment, the loop prevention mechanism can enhance the current draft of the standard ITU-T G.8032 Ethernet Ring Protection Switching.12-24-2009
20090316570FUTILE NEIGHBOR STATE LOOP PREVENTION IN HIGH AVAILABILITY NETWORKS - A method for detecting and managing a futile neighbor state loop during link state routing is disclosed. The method can include reading a threshold parameter for link state routing, wherein the threshold parameter indicates a number of routing attempts, and performing link state routing to a node via a primary interface. The method can further include detecting a futile neighbor state loop during link state routing to the node via the primary interface by detecting a number of routing attempts that has reached the threshold parameter and detecting an available backup interface to the node. The method can further include suspending the primary interface to the node and switching routing to the backup interface.12-24-2009
20100220586ROUTE REFLECTOR FOR A COMMUNICATION SYSTEM - A method, system and apparatus for routing of data transmitted from a mobile electronic device to a first host of a plurality of hosts in a communication network using a Border Gateway Protocol (BGP) is provided. It is determined that the first host has failed via receipt of BGP rerouted data at least one network element, the BGP rerouted data originally intended for the first host. A negative acknowledgement (NACK) is transmitted to the mobile electronic device from the at least one network element, the NACK enabled to trigger the mobile electronic device to transmit data that was to be transmitted to the first host to another of the plurality of hosts and wherein the NACK is identifiable by the mobile electronic device as having been transmitted by the at least one network element.09-02-2010
20100034079SERVICE MANAGEMENT IN A NETWORK - In a network (02-11-2010
20090323517AUTOLEARNING NETWORK LINK PROTECTION DEVICE - An apparatus and method for updating a network as to the link used by a protected network device when a first switch for the protected network device fails or is determined to be once again operational. The link protection device builds and transmits an update data packet on a second link for the protected network device that emulates a data packet sent from the protected network device on the second link.12-31-2009
20130128720METHOD AND APPARATUS FOR PROTECTION SWITCHING IN POINT-TO-MULTIPOINT NETWORK - A method of performing protection switching in a network including a first node and a plurality of second nodes that are connected to the first node is provided. The first node counts the number of obstacles that have occurred in a plurality of paths that are connected between the plurality of second nodes, and if the counted number is smaller than a predetermined threshold value, the first node performs protection switching per leaf. Alternatively, if the counted number is equal to or larger than a predetermined threshold value, the first node performs protection switching per tree.05-23-2013
20130128721SYSTEM TO IMPROVE AN ETHERNET NETWORK - A system to improve a Fibre Channel over Convergence Enhanced Ethernet (FCoCEE) network may include a sender in an FCoCEE network in which data packets having different data link layer structures are transmitted by the sender on a single data link. The system may also include a receiver to receive the data packets at the data link layer and to transmit an ACK and/or NAK in response to a sequence number in the data packets. The system may further include a replay buffer to retransmit the data packets where the replay buffer is sized by the length of the data link, data rate of the data link, the ACK and/or NAK processing time at either the sender and/or the receiver, and/or a threshold time for transmission and/or reception of the data packets.05-23-2013
20110019535COMPUTER PROGRAM, APPARATUS, AND METHOD FOR MANAGING NETWORK - In response to a route-changing event, original routes on the network are changed to new routes. A destination-reachable range is identified as a range from which packets can reach an information processing device specified by a destination address. Modification of forwarding data is performed for a neighbor communication device which is located outside the destination-reachable range and adjacent to a communication device in the destination-reachable range, so as to enable forwarding of packets to that communication device in the destination-reachable range. The modified forwarding data is then transmitted to the neighbor communication device. The modification made to the forwarding data results in an additional destination-reachable range, which is thus added to the destination-reachable range. Another cycle of processing is then performed on the basis of the expanded destination-reachable range.01-27-2011
20110211443NETWORK SWITCH WITH BY-PASS TAP - A network switch apparatus includes a first network port, a second network port, a first inline port, a second inline port, wherein the first and second inline ports are for communication with a pass-through device, a packet switch, and a by-pass device configured to operate in a first mode of operation, wherein in the first mode of operation, the by-pass device is configured to pass a first packet received at the first network port to the packet switch. The by-pass device is configured to switch from the first mode of operation to a second mode of operation upon an occurrence of a condition, and wherein in the second mode of operation, the by-pass device is configured to transmit a second packet received at the first network port to the second network port without passing the second packet to the packet switch.09-01-2011
20100135152ORDERED SWITCHOVER OF CABLE MODEMS - A cable modem termination system (CMTS) provides for ordered switchover of the cable modems it serves when a primary module of the CMTS fails. When the primary module in the CMTS fails, a backup module takes over service of the cable modems. The backup module restores the service flows of the cable modems based on a restoration order determined by session recovery priorities that are related to quality of service levels required by the service flows. In particular, service flows that are engaged in VoIP “911” calls are restored first. Service flows engaged in other VoIP calls are next restored. Lastly, service flows engaged in regular data sessions are restored.06-03-2010
20100128599TELEPHONE SYSTEM, GATEWAY FOR TELEPHONE SYSTEM, AND REDUNDANCY SWITCHING METHOD - According to one embodiment of the invention, there is provided a telephone system comprises gateways used to convert each other's protocols of IP network and PSTN. One of the gateways selectively serves as a main gateway, and the other gateways serve as slave gateways controlled by main gateway. Each of gateways includes a control channel manager, an operation controller and a determination module. Control channel manager of the main gateway controls speech data individually sent and received by gateways, based on a control signal of a control channel of PSTN. Operation controller controls redundancy switching between gateways upon occurrence of a fault. Determination module determines whether or not the fault is a fault associated with control channel. When the fault is a fault associated with control channel, determination module notifies slave gateway of message used to activate control channel manager of any of the slave gateways via IP network.05-27-2010
20110075552Apparatus and method for controlling data communication - In a communication apparatus, a receive data processor receives data and retrieves a group data record corresponding to the received data out of a group data memory. A forwarding processor forwards the received data according to the group data record retrieved by the receive data processor. The group data memory stores group data records which associate protection group identifiers with path selection data. The protection group identifiers each identify a protection group that provides logical paths constituting a redundant logical path for transporting a group of data, and their corresponding path selection data specifies which logical path to use to forward data in that protection group.03-31-2011
20090028043Method for relieving failure, and packet communication device - When a failure occurs on a path set between two packet communication devices, a protection path is set and the communication is recovered without having the effect of the path failure on devices other than the two packet communication devices. When a packet communication device detects a failure in a transmission line or a path between the device itself and a correspondent packet communication device to restore the communication, at least one of a topology modification notice pending step, in which the fact that the connection with the correspondent packet communication device being disconnected is not reported to the packet communication devices other than the correspondent packet communication device for a prescribed time, and a path restoration step, in which path setting signaling is performed to trigger cooperation of the path communication device and the correspondent packet communication device to set the protection path within the prescribed time, is executed together with a virtual interface setting modification step in which a virtual interface used for the path disconnected by the failure is set to the protection path.01-29-2009
20110069608System for providing backup programming at radio or television transmitter - A system transmits backup programming media in a transmitter station being connected to a remote media station. The media station includes a media programming input to receive a source media signal, which includes media programming. The media station further includes an Ethernet programming input that receives an Ethernet media signal including backup media programming being different the media programming. A transmitter station receives the source media signal via a transmission medium and transmits the media programming. The transmitter station further receives the Ethernet media signal and stores the backup media programming in a storage device. A controller detects a fault on a transmission medium connecting the media station and the transmitting station. The controller retrieves the stored backup media programming and generates a backup media signal. A transmitter transmits the backup media programming based on the backup media signal until it is controlled to re-transmit the source media signal.03-24-2011
20120201123HITLESS SWITCHOVER AND BANDWIDTH SHARING IN A COMMUNICATION NETWORK - Described is a node comprising a switch fabric and first and second ingress modules. The first ingress module receives a first stream of packets from a first physical path through the network; forwards a copy of the first stream of packets to an intermodule communication channel; selects packets from the first stream of packets and a copy of a second stream of packets for forwarding to the switch fabric. The second ingress module receives the second stream of packets from a second physical path through the network; forwards the copy of the second stream of packets to the intermodule communication channel; and selects packets from the copy of the first stream of packets and the second stream of packets for forwarding to the switch fabric based on sequence numbers in the packets.08-09-2012
20110013508NON-STOP FORWARDING IN A MULTI-CHASSIS ROUTER - State information is synchronized between a plurality of routing engines in a multi-chassis router according to a synchronization gradient. An example multi-chassis router is described that includes a primary routing engine and a standby routing engine in each chassis. According to the synchronization gradient, the primary routing engine of a control node updates state information on the standby routing engine of the control node prior to updating the primary routing engines of the other chassis. The primary routing engines of the other chassis update state information in respective standby routing engines prior to updating state information in consumers. If a primary routing engine fails, the corresponding standby routing engine assumes control of the primary routing engine's duties. Upon assuming control, a standby routing engine resumes updating state information without having to resend state information or interrupt packet forwarding.01-20-2011
20100254256METHOD FOR EFFICIENTLY TREATING DISTURBANCES IN THE PACKET-BASED TRANSMISSION OF TRAFFIC - A method for efficiently treating disturbances in a packet-based transmission of traffic via a routing protocol and routing entities includes reporting the nonavailability of a neighboring routing entity to a routing entity with regard to the routing by means of the routing protocol, initiating the sending of a test message from the routing entity to the neighboring routing entity for determining availability, wherein, when the nonavailability is confirmed as part of the verification, a failure of the connection to the neighboring routing entity is assumed, and initiating a change in the routing for avoiding the failed connection by the routing entity when nonavailability of the neighboring routing entity is confirmed.10-07-2010
20120170447METHOD OF AGGREGATING CONVENTIONAL RESOURCES UPON LOSING CONNECTIVITY TO A MASTER SYSTEM SITE - Communication systems and methods are presented for aggregating sites when connectivity to a core and zone controller therein is lost. A local controller provides multicast control to sub-sites within a locally aggregated network after detecting loss of connectivity to the core. The local controller assigns different multicast addresses than multicast addresses assigned by the zone controller. A sparse and dense mode protocol is used for multicast traffic outside and within the locally aggregated network, respectively. Conventional resources, but not trunked resources, are assigned addresses and groups. An isolated site is able to connect to the network in the event of core failure so that conventional multicast traffic traverses a direct link between each isolated site and the network, thereby extending the locally aggregated network. Multicast addresses available to be assigned by a local controller within any locally aggregated networks can be the same as those assigned by other local controllers.07-05-2012
20100309777NODE APPARATUS, PROCESSING UNIT, AND CONTROL FRAME PROCESSING METHOD - A method for processing a control frame for controlling path protection switching between redundant paths including a working path and a protection path, which is executed at one of two node apparatuses coupled mutually via the redundant paths, the method comprising: at the time of switching of the redundant paths, stopping monitoring whether the control frame has been received via a previous working path which is the path used as the working path until the switching is completed; determining whether the other of the two node apparatuses has stopped transmitting the control frame via a new working path which is the path used as the working path after the switching is completed; and starting monitoring whether the control frame has been received via the new working path, when it is determined that the second apparatus has stopped transmitting the control frame via the new working path.12-09-2010
20080205263System and method for advanced fail-over for packet label swapping - The present method for advanced fail-over packet label swapping for a packet network having a working path and a protection path, each of the working path and protection path interconnected by a near-end switch and a far-end switch includes: provisioning the working path, protection path, near-end switch, and far-end switch with a failure counter delay; monitoring heartbeat packets on one of the near-end switch and the far-end switch during a monitoring period to determine a number of packets that were not received by at least one of the switches during the monitoring period; determining if the determined number of packets exceeds a predetermined lost packet value for the failure counter delay; and responsive to the determined number of packets exceeding the predetermined lost packet value, delaying the monitoring for a period of time equal to the failure counter delay.08-28-2008
20100329111Multi-Active Detection Method And Stack Member Device - The present invention discloses a method of multi-active detection and a stack member device. Each member device in a stack is configured with a detection interface that is assigned an IP address, wherein the IP address of the detection interface on the designated active device is activated. Each member devices is also configured with an active device election rule, and with a correspondence between the IP address of the detection interface on each member device and the active device election parameter of the member device. Upon detection that the stack has become split, each designated standby device transitions to become an active device and activates the IP address of its detection interface. Each active device then uses the IP address of its detection interface as the source IP address to establish a session with other active devices, finds the active device election parameter according to the source IP address in the received session packet, and elects an active device that maintains its active state according to the configured active device election rule. The present invention implements multi-active detection in a stack.12-30-2010
20120147736Minimizing the Number of Not-Via Addresses - In an embodiment, a method comprises determining a set of protected components that are associated with a notifying node; determining a single network repair address for the set of protected components, wherein the single network repair address is for use in response to unavailability of any of the protected components when transmitting network traffic to the notifying node; assigning the single network repair address to each of the protected components; wherein the notifying node is an internetworking device and wherein the method is performed by one or more processors.06-14-2012
20110051596SYSTEM AND METHOD FOR ENHANCEMENT OF ETHERNET LINK LOSS FORWARDING - A system and method provide enhanced link loss forwarding in an Ethernet system to determine link degradation and to selectively block and re-establish transport between a near end device and far end device based on link status detection using local packets. When an excessive number of errors are detected in an Ethernet port, a device enters a Links Off mode from a Transport mode where Ethernet ports are turned off at both ends of a circuit associated with the errors. A Block Transport mode is then entered where local packets (e.g., OAM packets) are monitored to evaluate link quality. Transport mode is re-established when acceptable link quality is achieved for a selected period of time.03-03-2011
20120063299HIGHLY AVAILABLE VIRTUAL PACKET NETWORK DEVICE - A virtual chassis includes two or more physical chassis and operates as a single, logical device. Each of the two or more physical chassis include two route processor modules (RPM) and each RPM is assigned a first and a second role within the virtual chassis. The first role is a physical chassis level role and the second role is a virtual chassis level role. The RPMs operate in coordination such that the failure of any one of the RPMs results in one or more other RPMs taking over the first and second roles of the failed RPM.03-15-2012
20110305136ACTIVATION SIGNALING IN TRANSPORT NETWORKS - A method comprising the steps of receiving a signal indicative of a failure of a working connection in a mesh network having a headend node, a tailend node and an intermediate node, and having a protecting connection, and transmitting an activation message via the protecting connection from at least one of the headend node and the tailend node to the intermediate node for activating the protecting connection.12-15-2011
20120207013SYSTEM AND METHOD FOR MANAGING TRACKING AREA IDENTITY LISTS IN A MOBILE NETWORK ENVIRONMENT - A method is provided in one example embodiment and includes communicating a plurality of queries associated with common tracking areas in a wireless network; identifying a set of serving gateways that serve the common tracking areas; generating a tracking area identity (TAI) list to be used in provisioning network resources for user equipment; and selecting a first serving gateway from the set of serving gateways for the user equipment, wherein the first serving gateway is selected based on the common tracking areas served by the set of serving gateways. In more specific embodiments, the queries are domain name system (DNS) queries that are supported by a network element and that have no cached DNS response.08-16-2012
20120207014SYSTEM AND METHOD FOR ETHERNET PROTECTION SWITCHING IN A PROVIDER BACKBONE BRIDGING TRAFFIC ENGINEERING DOMAIN - A method of providing protection switching on a backbone network includes configuring a service instance table for a first port of a first bridge. The service instance table includes a Virtual Local Access Network (VLAN) identifier entry for one or more service instances. The method also includes mapping data traffic received at the first bridge onto a first trunk by setting a VLAN identifier entry for a first service instance and transmitting data traffic to a second bridge on the first trunk in accordance with the mapping and monitoring the first trunk for faults by exchanging continuity check messages with the second bridge over the first trunk. The method additionally includes, upon detecting a fault, remapping data traffic for the first service instance by changing the VLAN identifier entry for the first service instance and transmitting data traffic to the second bridge in accordance with the remapping.08-16-2012
20120008491RELAY APPARATUS FOR COMMUNICATION FRAMES AND RELAY METHOD - A layer 2 switch (L2SW) includes (i) a leaned information management unit for recording learned information that associates a receiving port, an address of another L2SW, and a source address specified in the original communication frame, when an encapsulated frame, in which a communication frame has been encapsulated by data containing the address of the another L2SW, is received from the backbone network and (ii) a status monitoring unit. The learned information management unit determines the update extent of the learned information, in accordance with a check result of the connection status and thus the occurrence of flooding transfer to a backbone networks side is suppressed.01-12-2012
20120057452FAILOVER AND FAILBACK OF COMMUNICATION BETWEEN A ROUTER AND A NETWORK SWITCH - A router is provided. The router includes a primary interface, a backup interface, a processor, and a memory. The primary interface and backup interface may be used to communicate with a network switch. The router may be configured to determine whether the primary interface is stable. The primary interface is stable when the primary interface may be used to exchange information with a network switch over a primary network segment. The router may be configured to activate the primary interface when the primary interface is determined to be stable. The router may also be configured to activate the backup interface when the primary interface is determined to be not stable. The backup interface may be activated for the exchange of information with the network switch.03-08-2012
20120127854METHOD OF SHRINKING A DATA LOSS WINDOW IN A PACKET NETWORK DEVICE - A packet network device includes a control module, one or more line cards each one or which includes a plurality of ingress and egress ports, and each of the ingress and egress ports are connected to external network links. The line cards maintain forwarding tables and include functionality that employs information in the forwarding tables to determine how incoming packets of information should be forwarded. The control module includes functionality that operates to learn reachability information about other devices connected to the network that are and to use this reachability information to update forwarding tables maintained on the line cards. The control module also includes an enhance ARP functionality that operates in cooperation with standard ARP functionality and other network protocols included on the control module to diminish the amount of data lost in the event that a link connected to one of the egress ports fails.05-24-2012
20120300617Method and Apparatus for Protecting Tunnel - The present invention discloses a method and an apparatus for protecting a tunnel, wherein the method comprises: setting a second protection group on two intermediate nodes of a first protection group; when a segment between the two intermediate nodes fails, adopting the second protection group to protect the tunnel. The present invention solves the problem in a relevant art that it is very difficult to configure multiple protection segments for one working segment and it might be limited by various conditions, such as network resources and the like; therefore, the utilization rate and the reliability of the network resources are improved.11-29-2012
20110090785ROUTE SWITCHING METHOD, SERVER, BOUNDARY NODE APPARATUS, ROUTE SWITCHING SYSTEM, AND ROUTE SWITCHING PROGRAM - A route switching method for switching a route in a core network that accommodates service networks including user node apparatuses by use of a server storing path information that includes, in every time frame, a route for a working path and a route for a backup path to be switched over from the working path, both of the working path and the backup path established between two boundary node apparatuses each of which is located on a boundary between the service network and the core network. The server calculates, in response to the connection request from the user node apparatus, a route for a working path and a route for a backup path, and requests the boundary node apparatus to establish this working path. The server can send the route for the backup path to the boundary node apparatus before a failure occurs in the core network. The boundary node apparatus establishes the working path in response to the establishment request for establishing the working path from the server, and can perform a quick recovery by switching over the working path to the backup path when a failure occurs in the core network.04-21-2011
20110090784METHOD AND APPARATUS FOR FAST REROUTE IN A CONNECTION-ORIENTED NETWORK - A method and an apparatus for rapidly resuming, at times of failures, network traffic in a connection-oriented network by using an alternative route pre-computed and stored locally in nodes along an initial route without requiring signaling of upstream nodes or a master server.04-21-2011
20120163162SPLIT MULTI-LINK TRUNKING (SMLT) HOLD-DOWN TIMER FOR INTERNET PROTOCOL (IP) MULTICAST - A method, apparatus and computer program product for providing mulitcast failover and recovery which minimizes lost packets is presented. A first network device returns to a fully active state and starts a multicast hold-down timer. A first message is sent to a second network device, the message indicating at least one Split Multi Link Trunk (SMLT) Virtual Local Area Network (VLAN) Identifier (ID) correlating to the multicast hold-down timer. The first network device receives an acknowledgment of said first message and Layer 2 forwards multicast data traffic to said second network device until the timer expires, whereupon the first device is capable of handling its own multicast data traffic, and then has Layer 2 bridging turned off and enables IP multicast routing. During the period of multicast hold-down timer, the second device will perform IP multicast forwarding on behalf of the first device.06-28-2012
20110176411METHOD FOR PROTECTING A PSEUDO-WIRE - A method and apparatus are provided for establishing a first pseudo-wire between a first item of input terminal equipment and an item of output terminal equipment, used by the first item of input terminal equipment. The method includes a step of transmitting a first message requesting establishment of the first pseudo-wire to an item of switching equipment, the first pseudo-wire to be established consisting of a first link between the first item of input terminal equipment and the item of switching equipment and of a second link between the item of switching equipment and the item of output terminal equipment. In such a method, the first establishment-request message also includes a request to establish at least one backup pseudo-wire consisting of the second link and of a third link to be established between the item of switching equipment and a second item of input terminal equipment.07-21-2011
20120134258METHOD, APPARATUS, AND SYSTEM FOR ACTIVE-STANDBY SWITCHOVER - The present invention relates to the field of communication technologies and discloses a method, an apparatus, and a system for active-standby switchover. The method includes: copying at least one packet group to a standby board; recording the copied packet group and generating a transmission rule chain table of an active board according to a sequence of copying, so that the standby board generates a transmission rule chain table of the standby board which is the same as the active transmission rule chain according to the sequence of copying; and transmitting the packet group according to the sequence of the transmission rule chain table of the active board. By using the method, resuming transmission from a breakpoint upon an active-standby switchover is enabled.05-31-2012
20120134257ROUTER AND RAPID RESPONSE NETWORK - A router includes a plurality of wireless network carrier cards, each of the network carrier cards adapted for use with one of a like plurality of different carrier networks, means for determining which of the plurality of network carrier cards provides a suitable connection to a carrier network and means for selecting one or more suitable connections to one or more carrier networks and for connecting the EVDO router to the carrier network through a particular one of the plurality of network carrier cards and a load balancing processor for load balancing between a plurality of different backbone networks and wherein the load balancing processor directs traffic among multiple networks to provide a desired throughput. In one embodiment, the router is provided as an evolution-data optimized (EVDO) wireless router.05-31-2012
20120163163APPARATUS AND METHOD FOR PROTECTION SWITCHING OF MULTIPLE PROTECTION GROUP - There is provided a protection switching apparatus including: a path management unit to establish a plurality of connection paths for transmitting/receiving packets, and a plurality of protection paths that are able to substitute for the plurality of connection paths, respectively, and to create a protection group including the connection paths and the protection paths; a protection group controller to determine whether failure has occurred on the connection paths, based on path state information for each path included in the protection group, the path state information stored in the protection group table storage, and to issue an instruction for protection switching, according to the result of the determination; and a protection switching unit to perform protection switching of a path in which failure has occurred to a protection path corresponding to the path in which failure has occurred, according to the instruction for protection switching.06-28-2012
20120250497METHODS FOR SENDING AND PROCESSING AN SIP RESPONSE - Devices, systems, and methods for sending and processing session initiation protocol (SIP) responses are disclosed. According to one aspect, a method for sending an SIP response through a first telecommunications network node is described. The method includes receiving, by means of the first node, a SIP request sent by means of a second node of the network. The method includes detecting an event that interferes with processing of said request by means of the first node. The method further includes sending, to the second node, a SIP response notifying said interference. The method also includes, before the sending step, activating, within the SIP response, a parameter that allows the request to be rerouted, said parameter being configurable by means of the second node.10-04-2012
20120075988FAST FLOODING BASED FAST CONVERGENCE TO RECOVER FROM NETWORK FAILURES - A router detects a network failure and responsive to that failure, floods a fast failure notification message out a set of interfaces of the router. The fast failure notification message includes information that identifies the network failure and includes as its source MAC (Media Access Control) address a MAC address that is assigned to an interface that is coupled with the detected network failure and is not part of the set of interfaces of the router. The router updates a routing table to reflect the network failure. The flooding of the fast failure notification message is performed prior to completion of the routing table update to reflect the network failure.03-29-2012
20120176890METHOD AND APPARATUS FOR USING G.8031 EXTENSIONS TO ENABLE COEXISTENCE OF G.8031-BASED PROTECTION AND LAG-LIKE LOADSHARING FOR ETHERNET PATHS - 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.07-12-2012
20120314564CASCADE SYSTEM FOR NETWORK UNITS - In one embodiment, a method is described for detecting an operational failure between the network unit and an adjacent network unit in the stack; controlling the switching engine to redirect packets which would otherwise be sent from a particular port to the adjacent network unit to be forwarded from another port to be sent to a different network unit in the stack; and entering the switching engine into a bypass mode in response to control data indicating an operational failure between at least two other network units in the stack to cause packets to be forwarded without being re-directed by the switching engine.12-13-2012
20120188867RECOVERY OF TRAFFIC IN A CONNECTION-ORIENTED NETWORK - A connection-oriented network (07-26-2012
20120082025PROTECTING MULTI-SEGMENT PSEUDOWIRES - The protection of multi-segment pseudowires by utilizing backup paths is disclosed herein. Disclosed embodiments include methods that establish at least one backup path for multi-segment pseudowires, the establishing being performed prior to detection of failure in the primary path. Upon detecting a path failure, the detected failure is signaled to the head-end, a backup path is chosen, and reachability information associated with the chosen backup path is signaled across the backup path before reverse traffic is switched to the backup path. In other disclosed embodiments, apparatus are configured to establish, prior to detection of failure in the primary path, at least one backup path for the multi-segment pseudowire.04-05-2012
20120230183METHOD AND APPARATUS FOR IMPLEMENTING CONTROL OF MULTIPLE PHYSICALLY DUAL HOMED DEVICES - A ring control protocol is used to establish a separate control plane for a plurality of physically dual homed devices to enable collections of dual homed devices to be represented by a single pair of addresses into the attached routed Ethernet network. The gateway devices analyze the passing ring control packets to create direct mappings for data packets to the routed Ethernet network. Thus, although the dual homed devices are treated as a ring from a control perspective, the data path is implemented to be direct so that data packets continue to flow directly from the dual homed devices to each of the attached gateway devices. In one embodiment, each of the gateway devices implements a virtual switch and advertises the MAC address of the virtual switch into the routed Ethernet network rather than the MAC addresses of each of the attached Ethernet Switch Units.09-13-2012
20110122762METHOD FOR UPDATING AN ADDRESS TABLE IN AN ETHERNET RING NETWORK NODE - The present invention provides a method for updating an address table in an Ethernet ring network node and an Ethernet ring network node. When the Ethernet ring network node implements a port state switching operation and a port on the ring is switched from an unblocked state to a blocked state, the Ethernet ring network node updates its forwarding database. The method and the Ethernet ring network node of the present invention can accelerate update of the FDB in the node when a link fails or is recovered, thereby improving the convergence speed for the switching when the ring network fails.05-26-2011
20080298229NETWORK WIDE TIME BASED CORRELATION OF INTERNET PROTOCOL (IP) SERVICE LEVEL AGREEMENT (SLA) FAULTS - In particular embodiments, receiving a first connectivity fault notification, establishing a predetermined time period when the first connectivity fault notification is received, receiving one or more additional connectivity fault notifications during the predetermined time period, performing a root cause analysis for the connectivity fault notification based on the received first connectivity fault notification, and resolving the first and the one or more additional connectivity fault notifications based on the root cause analysis are provided.12-04-2008
20120320737METHOD AND APPARATUS FOR LOSSLESS LINK RECOVERY BETWEEN TWO DEVICES INTERCONNECTED VIA MULTI LINK TRUNK/LINK AGGREGATION GROUP (MLT/LAG) - A method, apparatus and computer readable medium for maintaining two variables per port member of a network device which is part of a Split Multi Link Trunk/Link Aggregation Group (SMLT/LAG) is presented. A first variable comprising a link status variable reflecting a link status, and a second variable comprising a forwarding status variable reflecting a forwarding status of a forwarding plane with respect to the port are provided, the link status variable and the forwarding status variable in a first state when the port is operating properly. A failure related to the port is detected. The link status variable is set to a second state, and the forwarding status variable is set to a second state.12-20-2012
20120320736Providing resilient digital telephony services for wireless device - A system and method for providing resilient digital telephony services for wireless communication devices are disclosed. The system comprises a plurality of wireless communication devices and a border gateway serving a communications network that is configured to communicate with the wireless communication devices. At least two telephony servers are located in the communications network. The servers are configured to communicate with at least a portion of the wireless communication devices. A heartbeat module is configured to communicate heartbeat signals between the border gateway and the telephony servers and redirect service in the event of a server failure.12-20-2012
20110038255SYSTEM AND METHOD FOR GRACEFUL RESTART - A system for maintaining routing capabilities in a router having a failed control plane provides an active control plane in the router in communication with at least one external node, the active control plane running at least one routing process. A backup control plane may be interconnected with the active control plane, so that the active control plane may periodically transmit synchronization signals to the backup control plane. The backup control plane may update its state based on these synchronization signals. Moreover, the backup control plane may be programmed to take over the routing process of the active control plane if the active control plane fails.02-17-2011
20120127855METHOD AND DEVICE FOR CONVEYING TRAFFIC - A method and a device for conveying traffic are provided, wherein a master node is connected to a first slave node and to a second slave node; wherein the first slave node and the second slave node comprise a connection; wherein traffic is conveyed between the master node and the first slave node; and wherein in case of a fault condition the traffic is conveyed between the master node and the first slave node via the second slave node and the direct connection between the first slave node and the second slave node. Furthermore, a communication system is suggested comprising said device.05-24-2012
20120287777DYNAMICALLY UPDATING ROUTING INFORMATION WHILE AVOIDING DEADLOCKS AND PRESERVING PACKET ORDER AFTER A LINK ERROR - A system for allowing dynamic changing of routing information of a network interconnect while avoiding deadlocks and preserving packet ordering. A network resiliency system detects when an error in the network interconnect occurs and dynamically generates new routing information for the routers that factors in the detected error. The network resiliency system then generates new routing information that factors in the failure. The network resiliency system then directs the network interconnect to enter a quiescent state in which no packets are transiting through the network interconnect. After the network interconnect enters the quiescent state, the network resiliency system directs the loading of the new routing information into the routing tables of the network interconnect and then directs the network interconnect to start injecting request packets into the network interconnect.11-15-2012
20130010588High Availability Device Level Ring Backplane - A modular, high-availability network for an industrial control system employs a plurality of base modules having backplane and using network ring topology. Base modules may include I/O base modules for communicating with industrial processes or machines, an adapter base module for communicating with a programmable logic controller (PLC) and/or a bus expansion base module for providing additional I/O base modules. Base modules may be arranged side-by-side, having a backplane in a bank. Another embodiment may include having plurality of banks. The network ring topology used by the base modules is normally opened by a ring supervisor at the ring supervisor location. Upon failure of the network, the ring supervisor reconnects the ring to provide an alternative transmission path around the failure point.01-10-2013
20080253281Bandwidth Management for MPLS Fast Rerouting - Certain exemplary embodiments provide a method comprising: in a network at a node located on a label switched path: selecting a backup path to respond to a failure; and for each link along the backup path, reserving a backup bandwidth, wherein the backup bandwidth is sufficient to reroute traffic around the failure.10-16-2008
20080232244Proactive protection mechanism based on advanced failure warning - In one embodiment, an apparatus can include: (i) logic configured to detect an advanced warning indication, such as for a degraded signal condition, on a first link between first and second network devices, where the detection can utilize a number of corrected bits and forward error correction (FEC), for example; and (ii) logic configured to reroute packet traffic from the first link to a second link when the degraded signal condition is detected.09-25-2008
20130170335SYSTEM AND METHOD FOR CONVERGENCE AND AUTOMATIC DISABLING OF ACCESS POINTS IN A WIRELESS MESH NETWORK - One embodiment of the present disclosure sets forth a technique for convergence and automatic disabling of access points in a wireless mesh network. Specifically, an access point within a wireless mesh network computes one or more network metrics to determine whether the metrics are unfavorable or favorable. If the network metrics are favorable, then the access point disables the access point's network connection. An access point turns the network connection back on based on whether a routing was lost for at least a preset amount of time, utilization of one or more neighboring access points is above a preset value, or one or more network metrics have degraded by a certain percentage value. One advantage of this approach is that cost savings may be achieved when the number of access points dynamically changes to accommodate varying communications conditions.07-04-2013
20080225700Protocol Definition for Software Bridge Failover - A method, data processing system, and computer usable code are provided for protocol definition for software bridge failover. In a first aspect of the present invention, a first software bridge determines the proper working operation of a physical adapter. Limbo packets are sent to a second software bridge alerting the second software bridge that the first software bridge is no longer bridging traffic responsive to the physical adapter failure in the first software bridge. The second software bridge receives the limbo packets, and, in response to receiving the limbo packets, asserts primary control and initiates bridging of traffic. In an alternative aspect of the present invention a first software bridge sends keep-alive packets. A second software bridge monitors the keep-alive packets from the first software bridge and, in response to a failure to detect the keep-alive packets from the first software bridge, the second software bridge initiates bridging of traffic.09-18-2008
20080225699Router and method of supporting nonstop packet forwarding on system redundant network - A router (i.e., an electrical circuit) and method of supporting nonstop packet forwarding on a system redundant network are provided. The method includes, when the router again operates, identifying whether or not the router is connected with a neighboring router; and when the router is identified connected with the neighboring router, transmitting a link-up signal to a link to connect to a host node.09-18-2008
20130176843ROUTING PROTOCOLS FOR ACCOMMODATING NODES WITH REDUNDANT ROUTING FACILITIES - Graceful restart in routers having redundant routing facilities may be accomplished by replicating network (state/topology) information.07-11-2013
20080219150AUTO-NEGOTIATION BY NODES ON AN INFINIBAND FABRIC - A method and system for digital communication wherein nodes exchange messages at a first data rate in order to coordinate testing at a second, higher data rate. After testing is completed, the nodes exchange test results at the first data rate, and if conditions are satisfactory for operation at the second data rate user data are transmitted at the second data rate. Otherwise, user data are transmitted at the first data rate.09-11-2008
20130100798METHOD, NETWORK CARD, AND COMMUNICATION SYSTEM FOR BINDING PHYSICAL NETWORK PORTS - A method for binding physical network ports includes creating a virtual port, where the virtual port corresponds to a virtual network card in an application layer and is capable of being bound, in the application layer, with other created virtual ports through application layer software. The method also includes adding, to the created virtual port, multiple physical network ports, which need to be bound. When communications of the physical network ports in the virtual port is normal, the method includes identifying the physical network ports as being available. When a packet needs to be received or transmitted, the method includes selecting one or more physical network port from the available physical network ports according to a configured mode to receive or transmit the packet.04-25-2013
20130142034NETWORK DEVICE AND METHOD OF ROUTING TRAFFIC - A method for routing switch is disclosed. The method comprises: when a network device forwards traffic through N equal-cost multi-path (ECMP) routes to a destination, if M of these routes are inactive, then for each inactive route, determining an alternative route for replacing the inactive route from N-M active routes, and modifying the inactive route to the alternative route so as to switch the traffic of the inactive route onto the alternative route, wherein N and M are positive integer numbers, with N being greater than or equal to 2 and M being greater than or equal to 1 and smaller than N.06-06-2013
20130148492Method of Handling Delayed Signaling of Target Mobile device - A method of handling delayed signaling of a target mobile device for a first network control node is disclosed. The method comprises the first network control node receiving a request from a network gateway node; the registered network control node setting a flag and informing a data base to set the flag for the target mobile device when the first network control node fails to deliver the request to the target mobile device; and the first network control node sending the flag to a second network control node when the target mobile device is reachable in the second network control node.06-13-2013
20130155841SELECTING A MASTER PROCESSOR FROM AN AMBIGUOUS PEER GROUP - A distributed switch may include a plurality of special-purpose processors that control the different functions of the switch. To enable some special services, however, the distributed switch may need one of these processors to perform the role of a master. When a processor is powered on, the processor may publish a corresponding unique ID. Before electing the master, the special-purpose processors may use a discovery process to identify the network topology of the switch and evaluate the published IDs to determine which processor should be the master. If all the processors nominate the same master processor, then that processor is elected as the master and may finish configuring the distributed switch to enable the special services.06-20-2013
20090010153Fast remote failure notification - A method and system for failure notification at a remote node in communication with a local node are disclosed. The local node is configured for faster failure detection than the remote node. In one embodiment, the method includes establishing a failure monitoring session between the local node and the remote node, receiving at the remote node, a failure notification from the local node, the failure notification sent using a protocol of the failure monitoring session, and rerouting traffic at the remote node in response to the failure notification.01-08-2009
20130188474PAGING PROCESSING METHOD AND SYSTEM, SERVING GATEWAY - The embodiments of the present invention provide a paging processing method and system and also a serving gateway. The paging processing method includes: detecting, by a serving gateway, a fault of a mobility management element, determining a type of the fault, and reselecting a mobility management element according to the type of the fault; and sending, by the serving gateway, a downlink data notification message to the reselected mobility management element, whereupon the reselected mobility management element sends a paging message to a user equipment UE that is served by the faulty mobility management element before the fault occurs. With the method, system and serving gateway provided in the embodiments of the present invention, user experience is improved effectively.07-25-2013
20130201818METHOD FOR MANAGING A DEGRADED MODE OF A CELL IN A RADIOCOMMUNICATION NETWORK - A method for managing a degraded mode of a cell of a cellular network including a site controller for controlling, via a packet network, transmitters distributed over various sites of the cell such that transmitters implementing the same pair of frequencies over different sites form a channel which, in dynamic mode, is allocated dynamically to any communication between terminals of the cell, the channel including a master transmitter selected by the controller. The method includes, in each master transmitter on detection of a failure of the controller: switching in degraded mode of the master transmitter, by associating with the channel a predefined communication known to the terminals, and transmission from the master transmitter, via the network, of a control message informing a control console connected to the packet network of the implementation of the degraded mode so that the console participates in a communication underway in the channel.08-08-2013
20130208582SYSTEM AND METHOD FOR MULTIPOINT LABEL DISTRIBUTION PROTOCOL NODE PROTECTION USING A TARGETED SESSION IN A NETWORK ENVIRONMENT - A method is provided in one example and includes receiving first address information from a protected node over a first label switched path having a first label. The first address information is associated with a first network element. A second label switched path has been previously established with the first network element. The method further includes establishing a targeted session with the first network element, assigning a second label to the second label switched path, and sending the second label to the first network element over the targeted session.08-15-2013

Patent applications in class Packet switching system or element

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