Abstract: A method for providing a protected fast rerouting scheme for traffic conveyed in a network comprising a working path and a first backup path for conveying the traffic in case of a node failure. The method enables conveying traffic when two simultaneous failures occur, a failure of a link and/or of a node, belonging to the working path and the other—a failure occurring at a link and/or a node belonging to the first backup path. Upon detecting occurrence of a link/node failure along the working path, traffic is diverted to the first backup path, and upon detecting a concurrent failure at the downstream link/node at the first backup path, traffic is diverted to a second backup path extending from a node belonging to the first backup path and merges with the working path at a node located downstream of the failure that occurred at the working path.

Abstract: A method and system are provided for connecting at least three provider peer elements PEs located in two L2 network sites, via a provider network, wherein at least in one of the L2 sites and two of the provider peer elements PEs are connected to a customer equipment CE forming together a dual homing structure. The method and system are characterized in that they rely on the use of only a single PW in the provider network that extends between PEs of the two L2 network sites while ensuring traffic protection for the PW in the provider network, and ensuring that in case of a failure of one of the PEs or its connection to the customer equipment at one of the sites, the other L2 network site remains unaware of the failure, so that once established, traffic communication over the PW is maintained like no failure has happened.

Abstract: A dynamically self-configuring and re-configuring dual homing connection (DH) for loop-free data communication between a first communication network and a second communication network, the DH acquiring either a Symmetrical configuration or an Asymmetrical configuration.

Abstract: A method is provided for managing congestion of traffic in a packet switch, which comprises the steps of: providing more than two different congestion levels at the switch for handling traffic associated with at least two different priorities, one being a low priority traffic and another being a high priority traffic; for each traffic flow having a specific destination and priority, determining a current congestion level that matches a congestion control level which is selected from among the more than two congestion control levels, and associating a different set of operations for handling each respective traffic flow, depending on its priority and its current congestion level, and for each traffic flow, performing operations that match the respective associated set of operations, and wherein a rate at which these operations are performed for each respective traffic flow increases when a higher congestion level occurs at that respective traffic flow.

Abstract: A method for providing a protected fast rerouting scheme for traffic conveyed in a network comprising a working path and a first backup path for conveying the traffic in case of a node failure. The method enables conveying traffic when two simultaneous failures occur, a failure of a link and/or of a node, belonging to the working path and the other—a failure occurring at a link and/or a node belonging to the first backup path. Upon detecting occurrence of a link/node failure along the working path, traffic is diverted to the first backup path, and upon detecting a concurrent failure at the downstream link/node at the first backup path, traffic is diverted to a second backup path extending from a node belonging to the first backup path and merges with the working path at a node located downstream of the failure that occurred at the working path.

Abstract: A method for selective admission of traffic packets to a telecommunication switch having a limited throughput T and a common input queue, wherein the traffic packets comprise packets pre-assigned to higher and lower classes; in case of congestion at the common input queue of the switch, the method performs selective admission of the packets to the switch according to classes pre-assigned to them and depending on dynamic, recently utilized throughput of the switch.

Abstract: A method is described to enable carrying out a fast reroute protection technique which provides both link and node protection without traffic duplication, without the need to distinguish between link and node failures, and without replicating traffic. The technique covers concurrent Working and backup logical path failures, and in particular LSP logical paths. The method is adapted to provide a “Dual Failure Protection” (DFP), and is expandable to various multi-failure scenarios.

Abstract: A technique for protecting traffic in a Layer 2 (L2) communication network between a first and a second local nodes (CE1, CE2) interconnected via a redundant dual homed structure, the technique comprises a) distributing the traffic in the dual homed structure in a fault-free state, to form two traffic flows between the CE1 and CE2; b) providing Layer 2 (L2) fault indications for the dual homed structure, in the form of operation and maintenance (OAM) tools, c) in a faulty state of the dual homed structure, forwarding traffic packets at the provider edges of the structure, based only on conventional physical fault indications and L2 fault indications, by locally making forwarding decisions for selecting an active communication line via the redundant dual homed structure.

Abstract: Technique for fast rerouting (FRR) of traffic in a communication network, from a working path comprising a link with its downstream node, to one or more backup paths concurrently providing link protection and node protection to the link and the downstream node; the method comprises enabling the downstream node to block forwarding of traffic, if received at the downstream node along the backup path(s), towards a more-down-stream node in the working path in case the more-down-stream node participates in providing node protection against a failure of the downstream node, the technique thereby prevents traffic duplication at the more-down-stream node and does not require distinguishing a link failure from a node failure.

Abstract: A method is provided for managing congestion of traffic in a packet switch, which comprises the steps of: providing more than two different congestion levels at the switch for handling traffic associated with at least two different priorities, one being a low priority traffic and another being a high priority traffic; for each traffic flow having a specific destination and priority, determining a current congestion level that matches a congestion control level which is selected from among the more than two congestion control levels, and associating a different set of operations for handling each respective traffic flow, depending on its priority and its current congestion level, and for each traffic flow, performing operations that match the respective associated set of operations, and wherein a rate at which these operations are performed for each respective traffic flow increases when a higher congestion level occurs at that respective traffic flow.

Abstract: A method is described to enable carrying out a fast reroute protection technique which provides both link and node protection without traffic duplication, without the need to distinguish between link and node failures, and without replicating traffic. The technique covers concurrent Working and backup logical path failures, and in particular LSP logical paths. The method is adapted to provide a “Dual Failure Protection” (DFP), and is expandable to various multi-failure scenarios.

Abstract: A method for selective admission of traffic packets to a telecommunication switch having a limited throughput T and a common input queue, wherein the traffic packets comprise packets pre-assigned to higher and lower classes; in case of congestion at the common input queue of the switch, the method performs selective admission of the packets to the switch according to classes pre-assigned to them and depending on dynamic, recently utilized throughput of the switch.

Abstract: A technique for protecting traffic in a Layer 2 (L2) communication network between a first and a second local nodes (CE1, CE2) interconnected via a redundant dual homed structure, the technique comprises a) distributing the traffic in the dual homed structure in a fault-free state, to form two traffic flows between the CE1 and CE2; b) providing Layer 2 (L2) fault indications for the dual homed structure, in the form of operation and maintenance (OAM) tools, c) in a faulty state of the dual homed structure, forwarding traffic packets at the provider edges of the structure, based only on conventional physical fault indications and L2 fault indications, by locally making forwarding decisions for selecting an active communication line via the redundant dual homed structure.

Abstract: A dynamically self-configuring and re-configuring dual homing connection (DH) for loop-free data communication between a first communication network and a second communication network, the DH acquiring either a Symmetrical configuration or an Asymmetrical configuration.

Abstract: A method of finding a primary communication path in a mesh network, which would be at once a protected path having a fully guaranteed segmented node or node-link protection. The method comprises defining a required protection type and further selecting each specific path segment of the desired communication path based on initial user's requirements and topology information of the network. Each specific node path segment N for the communication path is selected upon ensuring that it can be protected in the network by a node backup path satisfying the initial user's requirements. Each specific link path segment L for the communication path is chosen if it can be protected in the network by a link backup path satisfying the initial user's requirements and if the node path segment N to which segment L leads cannot be protected by a suitable node backup path.

Abstract: Technique for fast rerouting (FRR) of traffic in a communication network, from a working path comprising a link with its downstream node, to one or more backup paths concurrently providing link protection and node protection to the link and the downstream node; the method comprises enabling the downstream node to block forwarding of traffic, if received at the downstream node along the backup path(s), towards a more-down-stream node in the working path in case the more-down-stream node participates in providing node protection against a failure of the downstream node, the technique thereby prevents traffic duplication at the more-down-stream node and does not require distinguishing a link failure from a node failure.

Abstract: A method of finding a primary communication path in a mesh network, which would be at once a protected path having a fully guaranteed segmented node or node-link protection. The method comprises defining a required protection type and further selecting each specific path segment of the desired communication path based on initial user's requirements and topology information of the network. Each specific node path segment N for the communication path is selected upon ensuring that it can be protected in the network by a node backup path satisfying the initial user's requirements. Each specific link path segment L for the communication path is chosen if it can be protected in the network by a link backup path satisfying the initial user's requirements and if the node path segment N to which segment L leads cannot be protected by a suitable node backup path.

Abstract: Technique for interconnecting a first communication network and a second communication network, for example layer 2 Ethernet networks, which uses a fully or partially redundant dual homing configuration. The configuration includes: at least three network elements where at least two of them are peer elements belonging to the second network, and at least two traffic lines respectively associated with the peer elements and connecting the first and the second networks via the three network elements. The technique comprises establishing a bi-directional signaling between the peer elements and, based on the signaling information, deciding which traffic line should forward the traffic.