Abstract: An interface system and method for creation and configuration of a connection between routers is provided. The interface comprises facility for entry of physical connection information, and entry of protocols selection and configuration information. Information for selection and configuring routing instances, network interfaces, and protocols for the connection is only requested from the user interface once before it is forwarded to an NMS to carry out the steps for actually setting-up the connection. Transport and protocol profiles for re-use with various physical connections are also provided.

Abstract: A method and apparatus for rerouting connections in a data communication network based on detection of faults or other undesirable characteristics using a user connection monitoring function is presented. After a connection is established that is managed by a control plane, the status of characteristics of the connection is monitored using a user connection monitoring function. In one embodiment, the user connection monitoring function includes the use of operation and management (OAM) cells. When the status of one or more of the selected characteristics being monitored is determined to be unacceptable, control plane rerouting of the connection is initiated. Selected characteristics that may be monitored using the user connection monitoring function include, for example, continuity, data corruption, data loss, latency, and misinsertion of data. The reroute initiated in response to the unacceptable characteristic may be a hard reroute or a soft reroute.

Abstract: A method and apparatus for handling, maintaining, and controlling network synchronization information emanating from a plurality of line card circuits is described. The technique described may be applied to a redundant pair of line card circuits, where one line card circuit is active, while the other is inactive. Line card activity latches are managed by means of hardware logic that may be configured at the time of line card commissioning. The activity latches are coupled to a logic element. An incoming clock signal is applied to the logic element. If an activity latch indicates that a line card circuit is active, the logic element provides the incoming clock signal as an outgoing clock signal to a control card circuit. If the activity latch indicates that the line card circuit is inactive, the logic element blocks the incoming clock signal from being passed and provides a static output level as the outgoing clock signal to the control card circuit.

Abstract: The present invention comprises a method and apparatus for automatic discovery of logical links between network devices. In one embodiment, the present invention comprises part of a network management system (“NM”) that manages a discrete set of network devices. The NM sends SNMP queries to individual network devices managed by the NM to obtain interface configuration data for each of the network interfaces of the device. The information requested includes destination information (“next hop” or “neighbor” IP address) for data packets sent from the interface. The NM checks to see whether a logical link corresponding to the received configuration information already exists in a logical link database maintained by the NM. If such a link exists the NM checks to see if the existing information for the link is valid. If the existing link data is valid, no change is made.

Abstract: An event processing system performs quickly processing of events in a communication network. The system comprises a client process that controls the sequencing of event processing, a plurality of servers that process the events with the help of a shared object library and a dispatcher that selects an available server so that no two servers process events from the same event queue at any given time. The client time-stamps the events and organizes them into event queues per node, using a node identification. An outstanding queue tracks the current events being processed for a node based on a message ID that is returned by the dispatcher when an event is sent to a server. Also, an overflow queue tracks the sequence of nodes to be serviced after a maximum outstanding limit of events being processed at a given time has been reached.

Abstract: An embodiment of a method and apparatus for synchronizing communication tasks (e.g., transmission control protocol (TCP) tasks) for redundancy in a network element is disclosed herein. The method includes an operation for receiving an inbound TCP packet at a TCP task of an active routing module of a network element. An operation is performed for queuing a first copy of the inbound TCP packet in a receive queue of the active routing module. After queuing the first copy of the inbound TCP packet, an operation is performed for forwarding a second copy of the inbound TCP packet to an inactive routing module of the network element. After receiving the second copy of the inbound TCP packet, an operation is performed for queuing the second copy of the inbound TCP packet in a receive queue of the inactive routing module.

Abstract: A method and apparatus that includes processing for providing distributed communication routing that, in one embodiment, begins by obtaining registration information from a plurality of forwarding engines, for identifying the plurality of forwarding engines based on the registration information, for generating at least one specific forwarding table for at least one corresponding forwarding engine of the plurality of forwarding engines, and for forwarding the specific forwarding table to the corresponding forwarding engine. In an alternate embodiment, the processing determines internal routing connections and external routing connections for the plurality of forwarding engines after identifying the forwarding engines, generates at least one external forwarding table for at least some of the plurality of forwarding engines, and generates at least one specific internal forwarding table for a corresponding forwarding engine. The tables are forwarded to the corresponding forwarding engine or engines.

Abstract: A method and apparatus for controlling multicast group subscriptions in a multicast distribution circuit is presented. When a router included in the multicast circuit receives notification to terminate support of a particular multicast group (group leave request), data flow with respect to that multicast group is initially maintained on the communication link coupling the router to the hosts. Queries are issued to hosts on the communication link to determine whether continued support of the particular group is desired by any hosts coupled to the communication link. If, while waiting for a positive response to the queries issued, a request to join an additional multicast group is received, bandwidth availability on the communication link is examined to determine if adequate bandwidth is available for supporting the newly requested group addition. If adequate bandwidth is available, the newly requested group is added to those groups supported on the communication link.

Abstract: An embodiment of the present invention provides a method for network management that allows the configuration of IP links in one step, via a GUI form, even though the management protocols available at the two end links (routers) may differ. According to one embodiment, the method comprises gathering information from the user, validating this information, and then sending this information to the appropriate router(s). According to one embodiment, the method enables a user to specify various configurations when provisioning an IP link, for example, the type of IP link (Point-to-Point, Point-to-IP, or Point-to-Subnet), the numbering type (Numbered or Unnumbered), the application type (MPLS and/or IP Forwarding), and the sub-layer interfaces to be used (Packet Over Sonet, Asynchronous Transfer Mode, GigEthernet, and others).

Abstract: In accordance with at least one embodiment, a method, apparatus, and article of manufacture are provided for configuring a virtual boundary register in a programmable logic device (PLD), transmitting a first user-definable-command operation code (opcode) to the PLD to effect programming of a memory device coupled to the PLD, and preferably transmitting a second user-definable-command opcode to the PLD, the second user-definable-command opcode causing the physical boundary scan circuitry to load the virtual boundary register. The foregoing is preferably achieved in accordance with a boundary scan standard (e.g., Institute of Electrical and Electronics Engineers, Inc. (IEEE) 1149.1, dated 2001).

Abstract: A method and apparatus for communicating data packets according to classes of service is described. One or more service interfaces are coupled to a plurality of transport interfaces. The service interfaces carry packets having multiple classes of service, while each of the plurality of transport interfaces carries packets of a single class of service. A differentiated services codepoint profile is associated with each service interface and maps a differentiated services codepoint value of a data packet to a class of service and a drop precedence. The data packet is assigned to a transport interface based on its class of service and its drop precedence. Other factors, such as the destination of the data packet may be considered when assigning the data packet to a transport interface. Data packets from different transport interfaces are preferably enqueued in different queues of a destination service interface.

Abstract: A method for distributing aggregate routes that does not require a user to provision a next hop address or specify a redistribution policy is presented. Embodiments of the method utilize a modified command language interface (CLI) with a network device (e.g., router). In the various embodiments, the modified CLI is well-suited for use in routers that utilize interior gateway protocols such as open shortest path first (OSPF), routing information protocol (RIP), integrated intermediate system-to-intermediate system (ISIS), interior gateway routing protocol (IGRP), enhanced interior gateway routing protocol (EIGRP), and NetWare link services protocol (NLSP). In one or more embodiments, the invention has the advantage of providing an easier means of specifying aggregate routes, which saves user time and is less error-prone.

Abstract: A method and apparatus for communicating and utilizing control plane congestion information in a communication network that utilizes a source routed signaling protocol is presented. When control plane congestion is detected at a network element within the communication network, a congestion notification message is generated corresponding to the detected control plane congestion. The congestion notification is then provided to at least one additional network element within the communications network. The at least one additional network element can then utilize this knowledge of the congestion within the network to perform various network functions, including the routing a connection set-up message.

Abstract: A method and apparatus for optimizing redundant link usage allows a portion of the wasted bandwidth in a redundant link system to be utilized for additional data traffic without compromising the ability of the system to respond to and correct for a failure of a link. In one embodiment, one of two independent, individually addressable links is selected as a nominal communication path, and the other as a standby communication path. The path independent traffic is sent via the nominal communication path, while the path dependent data is sent via the nominal communication path or the standby path, in accordance with the dependence of the traffic. In another embodiment, critical time sensitive traffic is sent via a nominal and standby time sensitive paths, while normal traffic is sent via nominal normal path, and non-critical traffic is sent via a standby normal path.

Abstract: A configurable chassis guidance system and method are described. The system may be practiced as a chassis and/or a module or an element thereof (e.g., a mating guide). The system and method allow reconfiguration of multiple modules of various module widths without the need for removal or reinstallation of module guides mounted on the chassis. As an example, a single-width module may be removed and replaced by a double-width module or quadruple-width module without removing module guides used to engage the single-width module. As another example, a double-width module or quadruple-width module may be removed and replaced by a single-width module without removing module guides used to engage the double-width module or quadruple-width module. The system and method may be practiced so as not to impair compatibility of modules with card edge module guides that engage an edge of a circuit board of a module.

Abstract: A method and apparatus for merging a plurality of virtual connections to form a merged virtual connection is presented. As cells for each of the plurality of virtual connections are received, they are buffered into a corresponding plurality of cell buffers, where each virtual connection has a corresponding cell buffer. When enough cells to constitute a complete packet are buffered for a particular virtual connection in its corresponding cell buffer, the identity of that virtual connection is queued into a queue, which may take the form of a linked list. A plurality of linked lists may be included such that differentiation between various virtual connections based on class is possible, where the class division may be based on a number of different factors. Prioritization information for the merged virtual connection is then obtained, where in the case where a plurality of classes are supported, the prioritization information includes class prioritization information.

Abstract: The present invention comprises a method and apparatus for providing a common support services infrastructure that allows a network element shelf to be used with circuit card configurations that provide enhanced and/or new data path functionality without requiring the expensive and time consuming redesign of the entire shelf unit. In one embodiment, the invention provides support services including common control and housekeeping services to a subshelf bay into which one or more subshelves may be installed. In one embodiment, the common support services that are provided include power supply services, environmental control services, information display services, and operational control and management services. In one embodiment, the subshelf bay is provided with standardized means used to supply the common support services to the subshelves. In one embodiment, each sub-shelf contains its own midplane and is operationally independent from other subshelves.