Alcatel Canada Inc.

Ciena Corporation

Alcatel Networks Corporation

Natalie Giroux

Brian Smith

Ken W Young

Chris Barrett

Pablo Frank

Mustapha Aissaoui

Tom Edward Davis

Charles Mitchell

Allan Beaudette

Raymond R Liao

Raymond Rui-Feng Liao

Denny L Lee

David Ross McDonald

Michael Gassewitz

Hossain Pezeshki-Esfahani

Bo Liu

Mustapha Aïssaoui

Charlie Sabry

Frederic Perras

Kenneth W Young

Andre Paquette

Ben Bacque

James D Arseneault

Kostic Predrag

Nicholas J Cadwgan

Ganti Sudhakar

Esmond Ho

Ali Rezaki

Angelo Bovolotto

Tom Davis

A system is provided for controlling the flow of data-packet traffic through an Ethernet telecommunications network having a multiplicity of nodes interconnected by multiple network links. Incoming data-packet traffic from multiple customer connections are received at a first node for entry into the network via the first node. Flow control messages are generated to represent the states of the first node and, optionally, one or more network nodes upstream from the first node, and these states are used as factors in controlling the rate at which the incoming packets are admitted to the network. Alternatively, the flow control messages may be used to control the rate at which packets generated by a client application are transmitted to the first node.

Smart ethernet edge networking system

Smart Ethernet edge networking system

A method of controlling the flow of data packet traffic from a first point to at least two second point in an Ethernet telecommunications network having a multiplicity of nodes interconnected by multiple network links, comprises monitoring the level of utilization of a link between the first and second points, generating flow control messages representing the level of utilization and transmitting the control messages to the first point, and using the states represented in the flow control messages as factors in controlling the rate at which the packets are transmitted from the first point to the second point. A method of controlling the flow of data packet traffic through an Ethernet telecommunications network having a multiplicity of nodes interconnected by multiple network links, comprises receiving incoming data packet traffic from multiple customer connections at a first node for entry into the network via the first node, the first node having an ingress trunk, and limiting the rate at which the incoming data packets are admitted to the network via the ingress trunk.

Efficient ethernet LAN with service level agreements

A method of testing a service connection within a container in an Ethernet network comprises coupling a test device to a port on a node in a path that includes the container, switching traffic of the service connection to the port, measuring selected parameters of the switched traffic in the test device, and using the measured parameters to evaluate the performance of the service connection. In one implementation, the switching uses service and container identifications, and switching the traffic to the test device is based on the service and container identifications. The test device may be capable of inserting traffic within the service connection, and the container may be a tunnel.

Ethernet service testing and verification

A method for managing data packets passing through an Ethernet node having multiple ingress ports and multiple egress ports, the ingress ports receiving the data packets from at least one service, and the egress ports configured with at least one Logical Transport Resource (LTR) configured as a predefined path between one of the egress ports and a destination in the Ethernet network. The method comprises mapping one or more of the services to each of the at least one LTR, shaping each of the at least one LTR to a configured rate, and transmitting data packets to the Ethernet network via the egress ports.

Logical transport resource traffic management

A method and system for detecting and controlling congestion in a multi-port shared memory switch in a communications network. The proposed congestion management scheme implements a local and a global congestion monitoring process. The local monitoring process monitors the queue depth. When the queue depth for any queue exceeds a queue length threshold a congestion control mechanism is implemented to limit incoming data traffic destined for that queue. Additionally, the global congestion monitoring process monitors the shared memory buffer and if the traffic thereto exceeds a shared memory buffer threshold a congestion control mechanism limits incoming traffic destined for any output queue which has been exceeding a fair share threshold value.

Congestion management in a multi-port shared memory switch

There is provided a method for transmitting non-real time traffic in a connection oriented communications network. The network includes a network core that has a source and a destination with a path between them. The non-real time traffic is received at the source from a number of connections and each of the connections is associated with one of many classes of transmission service. The method includes the first step of aggregating at the source the non-real time traffic received from the connections onto the path. The non-real time traffic is transmitted on the path without regard to the connections with which the non-real time traffic is associated. The method includes the second step of segregating at the destination the non-real time traffic so transmitted on the path within the core according to the corresponding connections with which the non-real time traffic is associated. Flow control is applied between the source and the destination to thereby regulate the rate of transmission of the non-real time traffic along the path.

Method and apparatus for provisioning traffic dedicated cores in a connection oriented network

In a method of fair queue servicing at a queuing point in a multi-service class packet switched network, incoming packets are received in buffers and outgoing packets are scheduled by a weighted fair queue scheduler. Real-time information of buffer usage along with the minimum bandwidth requirement is used to dynamically modify the weights of the weighted fair queue scheduler.

Fair queue servicing using dynamic weights (DWFQ)

A system and method for managing data traffic through a path that includes a transmission link having a transport rate that is subject to change with time. In one embodiment the data traffic is shaped to ATM Forum's available bit rate (ABR) category of service. ABR traffic has an integrated resource management (RM) cell that returns congestion related information to the source over a feedback path. With this congestion information the source end point is able to tailor its traffic send or transmission rate in order to accommodate or take advantage of any change in transport rate encountered by the traffic due to dynamically changing rate over the transmission link.

Controlling ATM layer transfer characteristics based on physical layer dynamic rate adaptation

A system and method for managing high speed traffic though switching elements in a digital network such as an asynchronous transfer mode (ATM) network. The system applies in particular to available bit rate (ABR) and unspecified bit rate (UBR) categories of service in an ATM network. ABR traffic incorporates resource management cells (RM) in a feed back loop from destination to source for the purpose of carrying explicit rate (ER) congestion control information. Lookup tables are provided in order to quickly provide ER information to the RM cells. UBR traffic is subject to cell discard in the event of congestion. Lookup tables are provided in order to fairly apply an early packet discard (EPD) algorithm.

High speed traffic management control using lookup tables

The method and system for buffering packets such as ATM cells at a queueing point of a device which employs a connection-orientated communications protocol includes the steps of logically partitioning a memory into plural reserved buffer spaces allocated to traffic classes and a shared buffer space available to any connection; determining whether to store or discard a given packet based on predetermined discard criteria; and filling the reserved buffer space to a predetermined state of congestion before storing the given packet in the shared buffer space. Reserved buffer space congestion states are defined with respect to individual connections, groups of connections, and the total capacity of the reserved buffer space itself. Packets are discarded when any, or alternatively a specific combination, of corresponding congestion states occur, and the shared space is congested as well. The system facilitates the balance between the sharing of physical memory resources amongst distinct and various types of traffic flows and the logical isolation thereof.

Flexible threshold based buffering system for use in digital communication devices

In an N&times;N packet switch, for example an ATM switch, multicast connections receive backpressure signals from congested output ports in the switch core. The cells in the connections are destination address modified not to send to the congested output port, but to continue sending to the other output ports in the connection. The multicast cells may include a user selected primary route identification and be queued in a unicast input queue for the primary route before being destination address modified. Destination address modification for congestion may be accompanied by partial packet discard, through destination address modification of the remaining cells forming part of a multiple cell packet to remove the destination address for the congested port (whether or not it is now congested) where one of the multiple destination addresses of one of the cells in the packet has been modified to remove the destination address of the congested output port. Destination address modification for congestion, without or without partial packet discard, may be accompanied by hybrid head of line blocking performed by not sending from a multicast queue if an output port on one of the multicast leafs is congested and the input queue size is below a given threshold, and sending with destination address modification and optional partial packet discard if the queue size is above the threshold.

Multicast methodology and apparatus for backpressure-based switching fabric

The method of the invention includes the step of transmitting a priority indicator containing information indicating the priority of network traffic over a connection to a downstream node in a communications network. The downstream node has a queue for queuing traffic received over the connection and the queue has an adjustable discard range. After transmitting the priority indicator, the network traffic is transmitted over the connection. When the priority indicator is received at the downstream node the discard range is adjusted to correspond to the priority indicated in the priority indicator. At the downstream node the network traffic is stored in the queue if a queue congestion measure is outside the discard range and discarded if the queue congestion measure is within the discard range. The priority indicator may be a Resource Management cell or may be provided in the header of a cell carrying the network traffic.

Method and apparatus for supporting multiple class of service connections in a communications network

In a connection oriented communications network such as an asynchronous transfer mode (ATM) network, virtual circuit (VC) connections are aggregated onto virtual path (VP) connections to simplify traffic management through core switching elements. This invention provides a system and a method of introducing network level fairness between VP connections in the core. Resource management (RM) cells are used to import relevant traffic weighting parameters from the VC/VP aggregation point to the VP switching element. The weighting parameters are used by a queuing scheme at each switching function to introduce a fairness level component to each VP.

Virtual path level fairness

A method of scheduling cells into an asynchronous network for a circuit emulation service, comprises estimating the virtual clock of each connection by on-line traffic measurement, determining the lateness of the head-of-the-line cell for each connection, and giving highest priority to the latest cell.

Growing community of inventors

Ottawa, Canada

Natalie Giroux