Telefonaktiebolaget Lm Ericsson (publ)

Francesco Paolucci

Piero Castoldi

Filippo Cugini

Giulio Bottari

Annikki Welin

Paola Iovanna

Roberto Magri

Nicola Sambo

Luca Valcarenghi

Alessio Giorgetti

Andrea Sgambelluri

Traffic recovery is supported at a switching node () of an OpenFlow network (). The switching node () has a flow table () for storing flow entries () which determine forwarding of received packets between the ports. A switching node () installs () a flow entry for a back up path in the flow table (). The switching node () renews () the flow entry for the backup path based on at least one of: (i) an association between the flow entry for the backup path and a flow entry for a working path at the switching node, wherein the flow entry for the backup path is renewed when the flow entry for the working path is used to forward a received packet; (ii) receiving a flow entry renewal packet from another switching node on the backup path. A backup path can be configured for each of multiple points of failure in the working path.

Traffic recovery in openflow networks

A path computation client (PCC) can request a path computation element (PCE) to compute a path across a wavelength switched optical network. PCC sends a request which identifies end nodes. The end nodes can support a plurality of possible values of a transmission parameter, such as modulation format or Forward Error Correction (FEC) type. The PCE computes a path between the end nodes and sends a reply to the PCC. The reply identifies the path between the end nodes and identifies a selected value of the transmission parameter for the computed path. The reply can comprise a spectrum assignment for the path. The reply can be a PCE Communication Protocol (PCEP) Reply message.

Path computation in wavelength switched optical networks

A system, method, and node for a Routing Controller (RC) to obtain from a Path Computation Element (PCE), network resource path metrics across a plurality of domains in a communication network in which each domain includes a plurality of Border Nodes (BNs). The RC sends to the PCE, a first message requesting a first path computation between each pair of BNs. The first message contains a maximum metric-value that a path computation must not exceed for a Path Computation Client (PCC) to consider the path computation acceptable. The RC then sends a second message requesting the PCE to compute a subsequent path computation for each BN pair for which the first path computation did not exceed the maximum metric-value. The second message contains a minimum metric-value that a path metric must exceed for the PCC to consider the path metric acceptable. The RC then receives the computed subsequent path computation.

Method and apparatus for path computation element and routing controller cooperation

A method of load balancing zero-bandwidth Traffic Engineering Label Switching Paths (0-bw TE LSPs) in a communication network having a plurality of network nodes and a plurality of network links connecting the nodes. The method may be implemented in a centralized Path Computation Element (PCE) or in an ingress router. Each equal cost path from a source node to a destination node is identified from network topology information. A probability of selecting each equal cost shortest path is determined using an iterative Global Load balancing Algorithm (GLA) and each 0-bw TE LSP is provisioned with a specific probability such that the 0-bw TE LSPs are uniformly distributed over all network links.

Global provisioning of zero-bandwidth traffic engineering label switched paths

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Pisa, Italy

Francesco Paolucci