Abstract: A method for fault protection in a bidirectional ring network includes transmitting first and second flows of packets around the bidirectional ring network while defining the first flow as a wrapping flow and the second flow as a non-wrapping flow. Upon detection by a node in the network that a segment of the network proximal to the node has failed, the packets in the first flow are wrapped at the node between clockwise and counterclockwise directions on the network so as to avoid the failed segment, while the packets in the second flow are not wrapped.
Abstract: A method for transmitting data over a channel includes receiving a first datagram for transmission at a first priority, and receiving a second datagram for transmission at a second priority, higher than the first priority, before the transmission of the first datagram is completed. The first datagram is divided into a plurality of fragments, including a first fragment and a last fragment. The fragments of the first datagram are transmitted over the channel, beginning with the first fragment. At least a fragment of the second datagram is transmitted over the channel before transmitting the last fragment of the first datagram.
Abstract: A method for data communications includes linking a plurality of edge devices to communicate with a remote network device via a network in accordance with a packet-oriented Layer 2 communication protocol. At each of the plurality of edge devices, incoming data frames are received from client nodes in accordance with respective native Layer 2 protocols, at least one of which is different from the packet-oriented Layer 2 communication protocol. The received incoming data frames are converted at each of the edge devices from at least a first format specified by the native Layer 2 protocols to a second format specified by the packet-oriented Layer 2 communication protocol. The incoming data frames are transmitted in the second format via the network to the hub.
Abstract: A method for establishing a connection with a guaranteed bandwidth for transmitting data over a logical link that includes a plurality of parallel physical links between first and second endpoints. A link bandwidth is allocated on each of the physical communication links so as to include a predefined safety margin, based on either a failure protection policy, or a measure of fluctuation that occurs in a rate of data transmission over the physical links, or both. A sum of the allocated link bandwidth over the plurality of the parallel physical links is substantially greater than the guaranteed bandwidth of the connection. The data are conveyed over the logical link by distributing the data for transmission among the physical links in accordance with the allocated link bandwidth.
Abstract: A performance management unit manages a primary interface and a standby or secondary interface to two channels of an optical communications network having APS capabilities. Each performance parameter is associated with three counters. First and second counters are linked to registers of the primary and the secondary ports, and the third counter is linked to the registers of the currently active port. When a protection switch occurs, the first and second counters are immediately read and reset. The third counter continues accumulating data, but becomes associated with the new active port. At the end of a read interval, the third counter correctly reflects the number of data received, regardless of switchovers between the primary and secondary channels.
Type:
Application
Filed:
February 25, 2002
Publication date:
October 21, 2004
Applicant:
Corrigent Systems Ltd.
Inventors:
Sharon Mantin, David Zelig, Shmuel Ilan, Leon Bruckman
Abstract: A method for data communications includes receiving a time-division-multiplexed (TDM) input signal carrying a payload comprising data and determining whether the data comprise synchronous or non-synchronous data. A first encapsulation scheme is selected if the data comprise synchronous data, and a second encapsulation scheme is selected if the data comprise non-synchronous data. The data are encapsulated for transmission over a packet-switched network in accordance with the selected encapsulation scheme.
Type:
Application
Filed:
March 24, 2003
Publication date:
September 30, 2004
Applicant:
Corrigent Systems Ltd.
Inventors:
Rafi Harel, David Zelig, Leon Bruckman, Nitzan Kappel
Abstract: A method for changing a network characteristic or capability, such as the communication rate of network segments, software version or protocol. All nodes in the network perform the change synchronously while continuing to communicate within the existing capabilities. A new configuration is downloaded to the nodes, and a manager node exchanges validation messages with the other nodes in order to verify that the nodes can be reconfigured and will be able to complete the process successfully. The manager node then sends a command message to the other nodes to execute the change. In response, the other nodes begin substantially simultaneously to communicate in accordance with the new characteristics and/or capabilities. This method helps to minimize the duration of the upgrade process, while avoiding traffic hits and minimizing abnormal operation that may occur during the upgrade.
Abstract: A performance monitoring system for a digital network is installed in network elements having performance monitoring responsibilities. Apparatus is provided for network elements, in which a bitmap representation of performance primitives detected during an acquisition interval is used as a control in the tracking and updating of network performance parameters. Immediate access to states that enable and inhibit the evaluation of individual performance parameters is available.
Abstract: A method for handling traffic in a communication network includes setting an aggregate limit on a total rate of transmission of information by a group of flows to be transmitted over the network, and setting a respective individual limit on an individual rate of transmission by each of the flows in the group. When the information carried by packets in any given one of the flows is in excess of the respective individual limit, the packets in excess of the respective individual limit in the given one of the flows are tagged with a first excess flow tag. When the total rate of transmission of the information is in excess of the aggregate limit, the packets in excess of the aggregate limit are tagged with a second excess flow tag. Resources in the network are allocated to convey the packets responsive to the first and second excess flow tags.
Type:
Application
Filed:
April 24, 2002
Publication date:
October 30, 2003
Applicant:
Corrigent Systems Ltd.
Inventors:
Leon Bruckman, Omer Goldfisher, Gal Mor, David Zelig
Abstract: A communication network includes a communication medium and a plurality of communication nodes, mutually coupled by the communication medium so as to form a ring, over which each of the nodes is configured to transmit traffic to the other nodes in both clockwise and counterclockwise directions around the ring. At least one of the nodes is configured to receive the traffic in only one of the directions at any given time.