Telefonaktiebolaget Lm Ericsson (Publ)

Ericsson Ab

Marconi Communications Gmbh

Other

Raoul Fiorone

Riccardo Martinotti

Andrea Corti

Stefano Ruffini

Orazio Toscano

Paolo Debenedetti

Luca Palmieri

Andrea Galtarossa

Daniele Ceccarelli

Sergio Lanzone

Francesco Fondelli

Antonella Sanguineti

Giuseppe Lorenzetto

Marco Santagiustina

Staefano Ruffini

Examples relate to a method of segment routing in a network node () of a network comprising a plurality of network nodes (). The method comprises receiving a segment routed packet () comprising a payload and having a segment route, and obtaining a target delivery time () from the received segment routed packet. The method further comprises determining () a time of arrival of the packet at a destination of the packet, and determining () if the time of arrival of the packet at the destination is prior to the target delivery time. For a determination that the time of arrival of the packet at the destination is prior to the target delivery time, transmitting () a packet comprising the payload towards the destination.

Segment routing network

There is provided a method and device for forwarding a digital signal arranged into portions that each contain a timestamp and an error detection code. Duplicates of the digital signal are received on a first optical path and a second, separate optical path. Corresponding timestamps are identified in the signals and used to synchronize corresponding portions of the signals. The error detection codes in the synchronized portions are used to allow one and only one of the corresponding portions to be selected for forwarding. The selected portions are then forwarded.

Method and device for forwarding a digital signal

A method of provisioning a control plane in a multi-technology network in response to a first connection request received from a client. The method comprises receiving the first connection request at a control plane dispatcher; analysing said first connection request and selecting a control plane based on results of the analysis and characteristics of control planes at the disposal of the dispatcher in the multi-technology network. The control plane dispatcher selects on a per connection request basis what is the best technology for that request and its requirements, taking also into account the status of the network resources.

Method and a device for provisioning control plane in multi-technology network

Aspects of the present disclosure relate to a method and a device for creating a data packet with discard eligible information and to a method and device for receiving a data packet with discard eligible information. Specifically, one aspect of the present disclosure provides a method for creating a data packet, containing a data payload and at least one label determining onward routing for the data packet, for onward transmission in a data communication system, a machine readable medium for implementing the method, and a corresponding device. In a first step a discard eligibility associated with the data packet is determined. In a second step, discard eligible information is encoded in a label determining onward routing for the data packet. In a third step an outgoing data packet including the label is generated.

Method and device for creating and for receiving a data packet with discard eligible information

The invention relates to a method of fault monitoring in a fault monitoring entity of a network node of a network having at least a first connection-oriented network layer, having first protection measures associated therewith, and a second connection-oriented network layer, having second protection measures associated therewith. In a first step the service condition status of the first network layer is monitored using the first protection measures. In a second step the second network layer protection measures are determined for onward transmission within the second network layer depending on the service condition status of the first network layer. Since the network node is aware of the monitored status condition of both the first and second layers the protection mechanisms for the first network layer and the second network layer can be co-ordinated and the second network layer protection measure for onward transmission may be determined for optimum network fault protection operation.

Fault monitoring in connection-oriented networks

Method of re-routing traffic in a communications network () in the event of a fault () on a path across the network, the method comprising, determining whether a first node (), located between the fault and a network ingress node (), is capable of switching traffic to an alternative path which avoids the fault, and if the first node is determined to be not so capable, then determining whether a second node (), located upstream of the first node, is capable of switching traffic to an alternative path which avoids the fault.

Re-routing traffic in a communications network

A connection-oriented network () has a plurality of connections terminated at a first node (N). A recovery group (A) is configured at the first node (N) comprising at least two of the plurality of connections (LSP-, LSP-, LSP-, LSP-). Fault detection is performed over each of the connections in the recovery group (A) and the node determines if at least one recovery group fault condition is met, based on the results of the fault detections performed over the connections in the recovery-group (A). When the at least one recovery group fault condition is met, the node causes traffic on the plurality of connections in the recovery group (A) to be transferred to backup paths. When the at least one recovery group fault condition is not met, and a fault has been detected on a connection in the recovery group (A), the node causes traffic to be transferred from that connection to a backup path.

Recovery of traffic in a connection-oriented network

Configuring a node () of a synchronization network involves identifying () possible alternative time synchronization trails arranged to carry time synchronization information for time synchronization at the node, and possible alternative frequency trails, arranged to carry frequency synchronization information for frequency synchronization at the node. Using information about the sources (), a comparison of the trails () is biased to increase a likelihood of choosing time synchronization and frequency trails which share the same source, over a likelihood of choosing trails with different sources. This can help avoid divergence and consequent bit errors arising from phase errors, resulting from trails having different sources. It can encompass for example changing both to a new common source, or changing one or both trails while still using the old common source.

Configuration of synchronisation network having synchronization trails for time sync and frequency sync

There is provided a method of optimizing timing packet transport in a network node, the method comprising using a locally available stable frequency reference at the network node to provide a pre-determined network node transit time for timing packets in at least one direction into or out of the network node. There is also provided a network node comprising a locally available stable frequency reference and circuitry adapted to apply a pre-determined network node transit time, L, to all timing packets transiting the network node in at least one direction into or out of a network node dependent on the locally available stable frequency reference.

Method and apparatus for optimizing packet timing transport

A connection oriented communications network has a plurality of nodes including a plurality of edge nodes. The network is arranged to define a primary tunnel connecting a primary one of the edge nodes to another edge node and a secondary tunnel connecting a secondary one of the edge nodes to another edge node. The network is arranged to enable switching of traffic from the primary tunnel to the secondary tunnel in the event of detection of a failure in the primary tunnel.

Resiliency schemes in communications networks

A method and a transport scheme for packets of traffic over a logical link made up of the aggregation of several physical links () connecting a transmitting side to a receiving side in which flows of incoming packets are sent to a scheduler/shaper () which selects therefrom packets for creating a global flow of packets falling within the bandwidth offered by the logical link on the basis of the bandwidth capability offered by the logical link. A distributor () distributes the global flow over the plurality of physical links () making up the logical link, oversees the physical links and sends to the scheduler/shaper signalling of a bandwidth decrease caused by failures of one or more physical links. The scheduler/shaper () is arranged to allow automatically for the logical link bandwidth variations while selecting the packets from the various incoming queues depending on the associated service class so as to cause the global flow to fall within the aggregated logical link bandwidth. This involves more queuing of packets and their possible drop according to the queue management criteria implemented, in the queues associated with the lowest service class.

Method and device for transmitting packets in a telecommunications network

A node () for an MPLS telecommunications network has interfaces () for OAM information exchange relating to a path for data traffic, between first and second other nodes each operating according to different OAM state machines for OAM information exchange. An OAM state machine mapper () maps the states of either of the different OAM state machines of the first and second other nodes into states recognized by the other of the different OAM state machines. OAM information exchange is according to either the first or the second OAM state machine and according to states mapped from the other of the OAM state machines, to support the path for data traffic through the node. By such mapping of the different states OAM information can be exchanged across corresponding boundaries and so paths no longer need to be terminated at the boundary to enable end to end operations.

Interworking for OAM information exchange

Network interconnection apparatus comprising a platform with interface ports for network interconnection and comprising in turn a first series and a second series of interface port cards and an interconnection unit for commanded interconnection at least between the cards of the first and second series and between cards of the first series. The cards of the first series have their own associated MAC address tables for addressing traffic between ports through the interconnection unit. Each entry of the table has an age field defining in time the age of the entry. The content of the age field is periodically verified and if it reaches a preset maximum figure the entry is updated on the basis of the content of the age field by a corresponding entry in the table of another card of the first series and associated therewith by the information in the entry to be updated. If the content of the age field of the corresponding entry is also a maximum figure, both the entries can be deleted.

Optimized synchronization of MAC address tables in network interconnection apparatuses

An apparatus and a method are described in which a flow of packets is distributed in several separate flows over several links () forming a logically aggregated link (). The flow outgoing from each physical link is sent to its own policer () which applies to said flow a traffic policing algorithm with the policers being interconnected to exchange algorithm control parameter modification information to fit them in among the various policers while allowing for the control parameters of the others so that a distributed policer () is realized.

Traffic policing

An apparatus for compensation or emulation of polarization mode dispersion (PMD) effects occurring in an optical signal traveling over an optical fiber based link comprises controllable birefringence sections and devices for polarization conversion. Each section comprises birefringence optical members or parts thereof, and each section is followed or preceded by one of the controllable devices for polarization conversion. The birefringence sections are at least three in number, and at least one of these has a propagation delay different from that of the other sections. The apparatus comprises a detection device for PMD output and control of the controllable devices for feedback adjustment.

Growing community of inventors

Genoa, Italy

Raoul Fiorone