Riverbed Technology, Inc.

Opnet Technologies, Inc.

James Mark Shaw

Raghavendra B Uppalli

Jerrold Stiffler

Pradeep Natarajan

Alain J Cohen

Pradeep Singh

Nitin Gupta

Vinod Jeyachandran

Rajesh Balasubramaniam

Krishnan Sivaramakrishna Iyer

Krisnan Sivaramakrishna Iyer

Sivaramakrishna Prasadam

Krishnan Sivaramakrishna Lyer

A method and system that takes advantage of processes that are efficient for determining the topology of small to medium size networks to determine individual network topologies for such networks, and then merges these individual topologies into a consolidated topology for the entire network. Each of the processes that determines the topology of the smaller networks provides the determined network topology, as well as a list of factors that may be relevant in the determination of how the given topology might be attached to any other given topology, such as the identification of a node that is not included in the given topology, or other indications of external connections. The merging process is configured to substantially restrict its analysis to these factors, thereby limiting the extent, and therefore the time consumed, by this stitching and merging process.

Stitching together partial network topologies

Potential paths between a source and destination of a network are identified based on trace-route information, then filtered to eliminate paths or links that are not supported by ancillary information associated with the network so as to identify feasible/actual paths between the source and destination. The ancillary information includes, for example, routing tables and ARP tables. If a feasible path cannot be identified based on the ancillary information, supplemental information regarding nodes further along the potential path is assessed to provide a basis for inferring the nodes that may provide a feasible path. The determined feasible paths are displayed for review, and provided to serve as filters for subsequent path-analysis tools.

Network multi-path discovery

The connectivity information provided by a variety of inference engines is integrated to provide a set of inferred links within a network. A consolidation is performed among inference engines that operate at a base level of connectivity detail to create a model of the network at this base level. The connectivity information provided by inference engines at each subsequent higher level of connectivity abstraction is then overlaid on the base level connectivity. By separately consolidating the connectivity information at each level of abstraction, the rules for dealing with conflicts can be simplified and/or better focused to resolve the conflict. By assuming that the more detailed lower level information is likely to be more accurate, rules can be developed to modify the connectivity models produced by the higher level techniques to conform to the lower level connectivity details while still maintaining the integrity of the higher level connectivity models.

Inferring connectivity in the presence of conflicting network data

A network analysis system invokes an application specific, or source-destination specific, path discovery process. The application specific path discovery process determines the path(s) used by the application, collects performance data from the nodes along the path, and communicates this performance data to the network analysis system for subsequent performance analysis. The system may also maintain a database of prior network configurations to facilitate the identification of nodes that are off the path that may affect the current performance of the application. The system may also be specifically controlled so as to identify the path between any pair of specified nodes, and to optionally collect performance data associated with the path.

Network path discovery and analysis

Networks and devices may communicate with each other using virtual connections. In one embodiment, a computer-implemented model is generated and includes a representation of the path of a virtual connection. The path of a virtual connection, such as an IP tunnel, is traced between its source and destination. The physical connection corresponding to such IP tunnels are found by tracing through the device configuration and routing tables at routers in the network. The path between the source and destination devices is traced until the path is terminated at the destination device, or at an interface to an external network. If the path ends at an external network, the path is traced from the destination device toward the source device until a corresponding interface to the external network is reached.

Method and systems for determining path of a virtual connection through a network

The embodiments improve the results of an auto-detection of network devices responsive to the causes of detection failures in preceding runs of the auto-detection process. The network may comprise various devices that are believed to be in the network. If a device that is believed to be in the network, but is undiscovered, the embodiments identify the device and information regarding the cause or causes of non-discovery. In response, the discovery parameters are modified, based on the causes associated with the undiscovered devices. The extent to which the discovery parameters are modified is based various criteria, such as the characterization of the network, or upon the detection of changes to the network.

Incrementally improved auto-discovery of network devices

Embodiments provide systems, methods, and computer program products for inferring the switch port connectivity of discovered but unmanaged devices in a network without direct access to the devices. Embodiments operate by generating a physical address-to-port map based on collected operational data and then pruning the generated map based on switch port connectivity information and/or inferred link connectivity information. The switch port connectivity of discovered unmanaged devices is then generated or updated based on the pruned map. The switch port connectivity information can be used by various other tools to enable diagramming, asset inventory, and network planning, design, and optimization workflows.

Detected IP link and connectivity inference

A network is partitioned into a set of independent partitions, and the topology of each partition is determined, then merged to form a topology of the entire network. Preferably, the partitioning is hierarchical, wherein the network is partitioned to form individual VLAN partitions, and each of the VLAN partitions is further partitioned based on the nodes that are simply connected to each port of one or more selected root switches within the VLAN partition. Simple connections to each port are efficiently determined based on an aggregate address forwarding table associated with each node. Ancillary information, such as spanning tree or CDP data, may be used to facilitate efficient partitioning and/or to validate inferences that are made with incomplete information.

Link inference in large networks based on incomplete data

A method and/or system is configured to improve the results of an auto-detection of network devices based on the causes of detection failures in preceding runs of the auto-detection process. As each device that is believed to be in the network is found to be undiscovered, the identification of the device and information regarding the cause(s) of non-discovery are stored. Prior to the next auto-detection run, one or more of the discovery parameters are modified, based on the causes associated with the undiscovered devices. The extent to which the discovery parameters are modified is preferably based on the apparent stability of the network, or upon the detection of changes to the network.

Incremental and targeted auto-discovery of network devices

The physical connection corresponding to IP tunnels in a network are found by tracing through the device configuration and routing tables at the routers in the network to determine the outbound interface associated with each tunnel endpoint, and then inferring a likely return interface associated with the opposite tunnel endpoint. Having determined the physical devices at the source and destination of each tunnel, the physical path between these source and destination devices is traced from the source toward the destination until the path is terminated at the destination device, or at an interface to an external network. If the path ends at an external network, the path is traced from the destination device toward the source device until a corresponding interface to the external network is reached.

Growing community of inventors

Cary, NC, United States of America

James Mark Shaw