Abstract: A network communication device for directing data units over a communication network includes at least one input and/or output port arranged to receive and/or transmit data units, a plurality of buffer units divided into several sub-pools, and a buffer allocator for allocating buffer units between the sub-pools. The buffer allocator is arranged to determine a priority value for each sub-pool based on quality of service for each connection established at at least one port. The buffer allocator is also arranged to determine a utilization value of the port, and arranged to allocate buffer units for each sub-pool based on the priority value and based on the utilization value. The buffer allocator creates a precedence list to ensures that a minimal number of connections, which are established at a most utilized port, will suffer data unit loss while receiving the data units.

Abstract: A method for determining the shortest simplest path in an optical network with mixed DWDM transmission characteristics, mixed switching methodologies (i.e. micro mirrors, bubbles, Electronic TDM, Electronic cross bar, optical signal regeneration, and wavelength translation using optical devices). Disclosed in the invention is: a.) a multi-layered network path determination method that resolves over-constrained routing requirements, b.) an application of A that resolves routing constraints described for the optical networking environment, c.) A Dense Mesh simplification method that reduces the computation and processing power to find the best approximate path through the network, d.) A caching strategy to cache approximate paths, rather than exact paths, and to age out cache entries just before they become incorrect e.) A method of calculating multiple metrics and checking them against routing requirements during the path determination process rather than afterwards (as is done usually) f.

Abstract: A network communication device for directing data units over a communication network includes at least one input and/or output port arranged to receive and/or transmit data units, a plurality of buffer units divided into several sub-pools, and a buffer allocator for allocating buffer units between the sub-pools. The buffer allocator is arranged to determine a priority value for each sub-pool based on quality of service for each connection established at at least one port. The buffer allocator is also arranged to determine a utilization value of the port, and arranged to allocate buffer units for each sub-pool based on the priority value and based on the utilization value. The buffer allocator creates a precedence list to ensures that a minimal number of connections, which are established at a most utilized port, will suffer data unit loss while receiving the data units.

Abstract: A system and method for detecting or reporting service level or service outages on a network includes a meta service generator that operates on a network inventory to generate service definitions. The system is a server-based model, and each service definition includes usergroup and points of presence, thus instantiating multiple services in a manner that allows the definition to focus on relevant element events amid massive network event data, and detect service outages quickly and dependably. The outages, transaction spec outages and events so determined may be aggregated to provide overall measures that are compared with thresholds, performance criteria and other service metrics specified in a user Service Level Agreement (SLA) for billing, credit, evaluation or other purposes.

Abstract: A network is monitored for reports indicative of a connection state among ports of a communications network. Certain ports are designated as being in a transition, and a transition table is created for each transition. The transition table includes locations that directly relate the connectivity of a first port with respect to a second port, as well as locations that relate the connectivity of other ports. The contents of the transition table are evaluated to determine the likely configuration of the communications network. State machines may be used to resolve conflicting data within the transition table, by providing a likely connection output based upon different entries within the transition table. A voting scheme is used to evaluate the outputs of the state machines and update the transition table when appropriate, and the updated transition table may also be evaluated.

Abstract: A logical representation of a communications network topology has links which represent connections within a network, and models of ports representing elements of devices which form the connections of the network. The logical representation is created and maintained in response to reports from the network, such as new neighbor reports and lost neighbor reports. A new neighbor module creates or changes the logical representation in response to new neighbor reports, based upon whether the reporting port is recently attached and whether the new neighbor port is recently attached. A lost neighbor module changes the logical representation in response to lost neighbor reports, by creating pseudo new neighbor reports, and allowing the pseudo new neighbor reports to be processed following a certain amount of time.

Abstract: A network is monitored for reports indicative of a connection state among ports of a communications network. Certain ports are designated as being in a transition, and a transition table is created for each transition. The transition table includes locations that directly relate the connectivity of a first port with respect to a second port, as well as locations that relate the connectivity of other ports. The contents of the transition table are evaluated to determine the likely configuration of the communications network. State machines may be used to resolve conflicting data within the transition table, by providing a likely connection output based upon different entries within the transition table. A voting scheme is used to evaluate the outputs of the state machines and update the transition table when appropriate, and the updated transition table may also be evaluated.

Abstract: Method and apparatus for providing a call-tapping point in a switched network with point-to-multipoint functionality. The tapping point is added as an additional destination for data being sent from a source node to a first destination node. The tapping point is also added as a destination for data being sent from the first destination node to the source node. A merge operation is performed for finding and combining common segments of the paths between the source and destination, the source and tapping point, and the destination and tapping point.

Abstract: Method and apparatus for determining a communications path between a source and a destination in an Internet Protocol (IP) network. The method determines a path list of next-hop routers between the source and destination by selecting between a Simple Network Management Protocol (SNMP) query of a current router on the path, and by sending a User Datagram Protocol (UDP) probe packet having a destination field with a destination IP address and a Time-to-Live (TTL) field with a value of one greater than the number of hops to the current router. The steps are iterated until the next router is determined to be the destination. Preferably, the UDP probe packets are loose-source routed through the source. In addition, a topology information database may be accessed to resolve an unknown router, and/or resolve intrarouter devices on the path.

Abstract: Method and apparatus for providing a call-tapping point in a switched network with point-to-multipoint functionality. The tapping point is added as an additional destination for data being sent from a source node to a first destination node. The tapping point is also added as a destination for data being sent from the first destination node to the source node. A merge operation is performed for finding and combining common segments of the paths between the source and destination, the source and tapping point, and the destination and tapping point.

Abstract: A logical representation of a communications network topology has links which represent connections within a network, and models of ports representing elements of devices which form the connections of the network. The logical representation is created and maintained in response to reports from the network, such as new neighbor reports and lost neighbor reports. A new neighbor module creates or changes the logical representation in response to new neighbor reports, based upon whether the reporting port is recently attached and whether the new neighbor port is recently attached. A lost neighbor module changes the logical representation in response to lost neighbor reports, by creating pseudo new neighbor reports, and allowing the pseudo new neighbor reports to be processed following a certain amount of time.

Abstract: A method for determining a best path from a source node to a destination node using a breadth first recursive search in parallel. The determination is based upon a plurality of metrics which are set by the system. A path's metrics are compared to respective threshold values and paths are discarded if the metrics values do not each exceed respective thresholds. In addition, if a path has no metric which is better than one of the already completed paths, the path is discarded.