摘要:
A connection-oriented network (5) has a plurality of connections terminated at a first node (N6). A recovery group (A) is configured at the first node (N6) comprising at least two of the plurality of connections (LSP1-6, LSP2-6, LSP3-6, LSP4-6). 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.
摘要:
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.
摘要:
A method of providing data from a first network 100 to a second network wherein a first PEJ and a second PEK node are provided in the first network 100 and are each capable of supplying data to the second network, wherein: i. at any one time one of the first PEJ and second PEK nodes provides data to the second network; and ii. the first PEJ and second PEK nodes are arranged to communicate with one another such that the other of the nodes can provide data to the second network if a fault is detected, wherein the communications between the first and second node allow a fault to be detected.
摘要:
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.
摘要:
A connection oriented communications network 10 comprises a plurality of nodes including a plurality of edge nodes 12, 14, 16, 18. The network is arranged to define a primary tunnel connecting a primary one 12, 14 of the edge nodes to another edge node 14, 12 and a secondary tunnel connecting a secondary one 16, 18 of the edge nodes to another edge node 12, 14, 16, 18. 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.
摘要:
A protection scheme for a metro optical network involves programming ingress nodes and egress nodes with a primary multicast label switched path (LSP) and a back-up LSP to provide one-to-one protection. The primary and back-up LSPs are configured prior to the occurrence of a network fault to allow the network to transmit multicast communication when the fault occurs. Particularly, multicast communications are sent on the primary LSP during normal operation. However, when a network fault occurs, the nodes also send a duplicate multicast communication over the back-up LSP. Configuring the primary and back-up LSPs prior to the fault occurring avoids the need for signalling to establish a working LSP after a fault occurs.
摘要:
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.
摘要:
Aspects of the present disclosure relates 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.
摘要:
Configuring a node (410) of a synchronization network involves identifying (10) 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 (20), a comparison of the trails (30) 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.
摘要:
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.