Patent application number | Description | Published |
20100020722 | Method for Discovering the Physical Topology Of A Telecommunications Network - A network (NW | 01-28-2010 |
20100054157 | Method And Apparatus For Network Tree Management - There is disclosed a manner of managing the active topology, that is the scheme for forwarding data, in a computer network such as an Ethernet local area network. A root bridge is selected from a plurality of bridges in the network; the root bridge calculating at least one spanning tree from a topology database that has been populated by bridge neighbor information gleaned from link state advertising messages. The root bridge may also calculate an alternate topology for implementation in the event a failure condition that affects the primary spanning tree is detected. The root bridge then advertises the spanning tree and remotely configures the port states of the bridges in the spanning tree through tree advertising messages that the bridges are arranged to process and set their ports accordingly. | 03-04-2010 |
20110013640 | METHOD AD APPARATUS FOR ETHERNET PROTECTION WITH LOCAL RE-ROUTING - A method is provided for use at a first node of a network. The first node (B) has an input path for receiving Ethernet frames destined for a second node of the network. The first node (B) also has a first output (working) path for forwarding the received Ethernet frames towards the second node. A failure along the first output (working) path is detected at the first node. Following such failure detection, the received Ethernet frames are caused, at the first node, to be re-routed along a second output (backup) path, different to the first output (working) path, towards the second node. The re-routing is performed by using (e.g. referring to and/or changing) respective indications (VLAN | 01-20-2011 |
20110022725 | METHOD AND APPARATUS FOR LINK-STATE HANDSHAKE FOR LOOP PREVENTION - A network node of a telecommunications network controlled by a link-state protocol includes a network interface which receives a message that contains information on a change in topology of the network. The node includes a processing unit that blocks forwarding of traffic to at least one neighbor node of the network at the network interface, agrees on the change in topology with the neighbor node; and unblocks the forwarding of traffic when the neighbor node has information about the topology which is the same as the information about the topology in a memory. A transient loop prevention method of a network node of a network having a plurality of a network nodes controlled by a link-state protocol includes the steps of receiving a message at a network interface which contains information on a change in topology of the network. There is the step of blocking forwarding of traffic to each neighbor node of the network at the network interface by a processing unit. There is the step of agreeing by the processing unit on the change in topology with the neighbor node. There is the step of unblocking the forwarding of traffic when the neighbor node has information about the topology which is the same as the information about the topology stored in a memory. | 01-27-2011 |
20110080854 | Method And System For Controlled Tree Management - There is disclosed a method and apparatus for facilitating a network, such as an Ethernet LAN, for efficient forwarding of data traffic by collecting neighbor information, generating and distributing link state advertisements, populating a topology database for the network, and calculating trees for each bridge serving as a root bridge. In a preferred embodiment the method and system also prepare one or more backup topologies, and store them for use if they are needed due to a failure condition detected in the network. In a particularly preferred embodiment, probabilities are assigned to various potential failure conditions, and the probability values are used to decide which backup topologies to calculate, store, or use. | 04-07-2011 |
20110116418 | Multiple Tree Registration Protocol - A registration protocol for setting up and updating a tree that defines the active topology in an Ethernet network includes a plurality of application components and a plurality of attribute declaration components corresponding to the application components, wherein the application components declare and register attribute values and the corresponding attribute declaration components make and withdraw registration of the attributes. | 05-19-2011 |
20110205884 | Method and Arrangement for Failure Handling in a Network - A method and arrangement for failure handling in a tree-structured communications network having interconnected edge nodes and switching nodes. VLANs may be established by using spanning trees to provide connectivity in case of a failure in the network. Emitters in the edge nodes periodically broadcast alive messages on the VLANs, and notifiers note the alive messages. A missing alive message indicates a failure on one of the VLANs, and the notifier broadcasts corresponding failure messages on the VLANs. When the alive messages are restored, the notifier broadcasts corresponding repair messages. If a notifier fails to note a failure, one of the edge nodes performs a similar function although somewhat slower. | 08-25-2011 |
20110310904 | L2 METHOD FOR PARTIAL VLAN SERVICE MIGRATION - An upgraded edge node (e.g., enhanced PBB edge node, enhanced IP/MPLS edge node) and a method are described herein for providing a VLAN service for a customer in a metro network. In addition, a metro network is described herein which includes the upgraded edge nodes, traditional PB edge nodes, and a PB domain that has PB core nodes located therein. | 12-22-2011 |
20120106322 | TECHNIQUE ESTABLISHING A FORWARDING PATH IN A NETWORK SYSTEM - A method and network for determining an interconnect node for establishing a forwarding path for service based data within a network system. The method includes assigning, interconnect node status information to network interconnect nodes, wherein a network interconnect node to which a passive status is assigned is only allowed to transmit service based data between an external link and another interconnect node of the network, or between two other interconnect nodes of the network. Only a network interconnect node with active status is allowed to send or receive service based data to or from the network. The method includes determining, for a given service, an interconnect node with active status for establishment of a forwarding path including the interconnect node with active status and an external link, wherein the determination is based on the respective status information assigned to the network interconnect nodes for the service. | 05-03-2012 |
20120106347 | LOAD BALANCING IN SHORTEST-PATH-BRIDGING NETWORK - A flow classification process is used at the edge of the shortest path bridging network to determine a flow label for attachment to a client frame entering the network. Any of several flow labels can be assigned to a client frame traversing the network to a particular egress node, and the flow labels are used by forwarding nodes to select among multiple equal-cost paths. In several embodiments, the flow label is calculated as a function of the client frame contents, which provide an entropy source for randomizing the selection of the flow label. This entropy source comprises the Internet Protocol (IP) header in the client frame, in some embodiments, but may comprise other client frame content in other cases. | 05-03-2012 |
20120120803 | NODE AND METHOD FOR COMPUTING FORWARDING TREES TO DISTRIBUTE TRAFFIC IN A NETWORK - A node and a method are described herein for computing forwarding trees to distribute traffic in a network. In addition, a network is described herein that has a plurality of nodes interconnected to one another by a plurality of network links, and each node is configured to perform multiple rounds of forwarding tree computations to distribute traffic load on one or more of the network links to the other nodes. | 05-17-2012 |
20120170489 | Method And Apparatus For Network Tree Management - There is disclosed a manner of managing the active topology, that is the scheme for forwarding data, in a computer network such as an Ethernet local area network. A root bridge is selected from a plurality of bridges in the network; the root bridge calculating at least one spanning tree from a topology database that has been populated by bridge neighbor information gleaned from link state advertising messages. The root bridge may also calculate an alternate topology for implementation in the event a failure condition that affects the primary spanning tree is detected. The root bridge then advertises the spanning tree and remotely configures the port states of the bridges in the spanning tree through tree advertising messages that the bridges are arranged to process and set their ports accordingly. | 07-05-2012 |
20120281524 | Technique for Controlling Data Forwarding in Computer Networks - Technique for controlling data forwarding in a computer network are provided. The network comprises a set of nodes for forwarding data, wherein a first node is associated with a primary tree and a backup tree, wherein the primary tree defines a default path for the first node to forward data to a second node and the backup tree defines another path for the data forwarding in case of a failure of the primary tree. The basic principle of the techniques is to notify the first node of a failure of the primary tree wherein the notification is provided by the second node. The techniques are particularly beneficial for computer networks offering multipoint services, such as SPB-controlled networks, because the techniques ensure the congruency of the forward and reverse paths even when the data forwarding has been switched from the primary tree to the backup tree. | 11-08-2012 |
20120320758 | LOSS MEASUREMENT FOR MULTICAST DATA DELIVERY - A method of measuring loss in a multicast transmission in a network is described. Service frames including a service multicast destination address are sent from a source node towards a receiving node. A counter of the number of service frames sent is maintained at the source node. This counter is periodically read, and its value copied into a loss measurement OAM frame. The loss measurement OAM frame includes a unique identifier and an OAM destination address which is different to the service multicast destination address, and is sent from the source node towards the receiving node. Every time the sent frames counter is read, a measurement indicator frame is also sent from the source node towards the receiving node. The measurement indicator frame includes the unique identifier so that it can be related to the loss measurement OAM frame. The measurement indicator frame also includes the service multicast destination address, although the measurement indicator frame is distinguishable from the service frames. The receiving node eventually receives the loss measurement OAM frame and the measurement indicator frame, and calculates the number of lost or delayed service frames by comparing the number of service frames received at the receiving node at the time the measurement indicator frame is received with the sent frames counter value contained in the loss measurement OAM frame. The calculation is only performed when the loss measurement OAM frame and measurement indicator frame having the same identifier have been received by the receiving node. node. | 12-20-2012 |
20130194973 | In-Service Upgrade of Provider Bridge Networks - A system and method for in-service migration for a Virtual Local Area Network, VLAN, service if a Provider Bridge Metro Ethernet Network, PB MEN, is upgraded to a Provider Backbone Bridge, PBB, MEN or an Internet Protocol/Multi Protocol Label Switching, IP/MPLS, MEN. After the deployment of the new PBB or IP/MPLS technology, a sequence of management actions are performed to configure PBB or IP/MPLS edge nodes to use the new technology as well as the old PB-based technology to support the VLAN service. Both old and new connectivity structures are maintained in the edge nodes during the entire migration process. Customer traffic is then redirected per edge node to the new technology. When each edge node entirely provides the VLAN service under the new technology, the migration is complete. | 08-01-2013 |
20130195111 | Shortest Path Bridging in a Multi-Area Network - A method that improves multi-area routed Ethernet network design, in which multipath implementation in each of the areas is independent of each other area to allow optimal network design in each area. The network implements a shortest path bridging medium access control (SPBM) protocol. The areas include a Level 2 (L2) routing area coupled to a Level 1 (L1) routing area via multiple area border bridges (ABBs). The L1 routing area including a backbone edge bridge (BEB) coupled to the ABBs via multiple L1 multipath instances identified by respective backbone VLAN identifiers (B-VIDs). The ABBs receive an advertisement from the BEB that indicates a set of BEB identifiers, each of which identifies the BEB and is associated with a respective B-VID. Each of the BEB identifiers is unique. The ABBs also advertise into the L2 routing area, and translate the B-VIDs based on service identifiers for frames transiting the ABBs. | 08-01-2013 |
20130246635 | Technique for Bundling in Link Aggregation - Methods and apparatus are disclosed for applying multiple Link Aggregation Group (LAG) entities on the same set of physical links, thus making bundling of individual services or conversations possible by the different LAG entities within Link Aggregation. Each LAG entity is configured such that a single physical link is Active and all the other links are Standby. Each LAG entity may be regarded as a “bundle.” Thus the services/conversations are bundled into a LAG entity and are handed-off on the Active link during normal operation. If service hand-off is not possible on the Active link (e.g., due to a failure), then the LAG entity switches over to a Standby link thus the service/conversation is handed-off on that formerly Standby link. Bundling may simplify operations of control and signaling. | 09-19-2013 |
20130254327 | DATA PLANE FOR RESILIENT NETWORK INTERCONNECT - The present disclosure relates to a technique for forwarding frames received by a network interconnect node ( | 09-26-2013 |