Abstract: In address-manipulation enabled transaction accelerators, the transaction accelerators include outer-connection addressing information in packets emitted over an inner connection between transaction accelerators and inner-connection addressing information is added in packets sent over the inner connection. The inner-connection addressing information can be carried in TCP option fields, directly in other fields, or indirectly through data structures maintained by the endpoints processing the connection. Address information can be encoded into header fields originally intended for other purposes but that are unused or encoded into used fields, overlaid in combination with other data that is being carried in those used fields. The existence of inner-connection addressing information in a packet can be signaled by a flag in the packet, by a bit or other designated encoding. The flag can be in an unused header field or overlaid.

Abstract: A network capture element is embodied on a virtual machine, and a utility function is embodied on the actual device, preferably within the virtual machine manager. Both the utility function and the traffic capture element are configured to monitor communication events. To minimize the overhead imposed, the utility function is configured to merely store the time that the event occurred on the actual machine, corresponding to an identifier of the event. The network capture element, on the other hand, performs the time consuming tasks of filtering the communications, selectively storing some or all of the data content of the communications, characterizing the data content, and so on. Instead of storing the virtual time that the communication event occurred at the virtual machine, the network capture element uses the identifier of the communication event to retrieve the actual time that the communication event occurred on the actual machine.

Abstract: A single-ended optimized storage protocol enables storage clients or other devices to direct a remote data storage to copy data. In response to commands via the protocol, a remote data storage can copy portions of a data stream at the remote data storage to destination storage locations within the same or a different data stream. The protocol may be utilized for optimized transfer of data via a network to a remote data storage. An initial data stream is divided into segments. Redundant segments are removed from the data stream to form an optimized data stream, which is transferred to the remote data storage. Commands are issued to the remote data storage using the protocol to direct the remote data storage to reconstruct the initial data stream at the remote data storage using the optimized data stream and optionally segments from other data streams previously transferred to the remote data storage.

Abstract: The file creation on remote data storage accessible via a WAN can be optimized by creating temporary files in advance on a remote data storage. The file handles or other file access parameters for these temporary files are cached at a client network location. A file creation request from a client is intercepted at the client network location and one of the cached file handle is returned to the client. This enables the client to immediately write data to the corresponding temporary file, avoiding the delay incurred by communicating the file creation request and its response over a WAN. One or more storage commands are sent to the remote data storage to change the attributes of the temporary file to match those requested by the client, such as the file name, directory, and/or file permissions. File creation requests may be selectively optimized according to rules or criteria specified by users.

Abstract: Embodiments provide systems, methods, and computer program products for network management application to automatically determine a session prompt for a network device and perform error handling. After logging in to a network device, the network management application records the first session prompt response. The network management application sends a series of empty carriage returns and random characters and records the session prompt responses. The network management application compares the responses and determines whether the prompt is a static or a dynamic prompt based on the results. The network management application elicits error responses from the network device by sending additional random characters and records the results in an error handling dictionary. The error handling dictionary is used later when running user-provided commands, enabling a determination of whether a command executed successfully.

Abstract: Embodiments provide systems, methods, and computer program products for monitoring application performance in multithreaded environments. Monitoring data may be inserted into data structures that propagate and persist between threads involved in a processing event. Data related to specific methods executing on each thread may be output to a trace file. The trace file may be analyzed for application performance by associating the threads that contain the same tracking data from the propagated data structure.

Abstract: In a network that includes static bandwidth and dynamic bandwidth links, traffic flow at the OSI network layer is simulated at a traffic-flow level at interfaces to fixed bandwidth links, and simulated at a discrete-packet level at interfaces to dynamic bandwidth links. The resultant discrete-packet reception events at the receiving interface(s) of the dynamic bandwidth link are processed to determine the effective bandwidth/throughput of the link, as well as the allocation of this bandwidth among the individual flows through the link. The discrete-packet level receptions are used to reconstruct the parameters of the traffic flow at the network layer of the receiving interface, and this determined traffic flow is simulated accordingly at the next link, depending upon whether the next link is a static or dynamic bandwidth link.

Abstract: The present system includes a system, method and device for inferring connectivity between unconnected network segments. In operation, unconnected network segments are identified. Configuration data related to the unconnected network segments may be examined to facilitate inferring configuration data for an external network connected between the unconnected network segments. The inferred configuration data may be rendered, such as exported or visualized. The inferred configuration data may be related to a communication protocol and/or may be related to network bandwidth. The examined configuration data may be captured directly from one or more of the unconnected network segments and/or may be retrieved from a configuration data file, such as a network configuration model.

Abstract: A method and apparatus are provided for scheduling a heterogeneous communication flow. A heterogeneous flow is a flow comprising packets with varying classes or levels of service, which may correspond to different priorities, qualities of service or other service characteristics. When a packet is ready for scheduling, it is queued in order in a flow queue that corresponds to the communication flow. The flow queue then migrates among class queues that correspond to the class or level of service of the packet at the head of the flow queue. Thus, after the head packet is scheduled, the flow queue may be dequeued from its current class queue and requeued at the tail of another class queue. If the subsequent packet has the same classification, it may be requeued at the tail of the class queue or may remain in place for another servicing round.

Abstract: A log structured content addressable deduplicated data storage system may be used to store deduplicated data. Data to be stored is partitioned into data segments. Each unique data segment is associated with a label. The storage system maintains a transaction log. Mutating storage operations are initiated by storing transaction records in the transaction log. Additional transaction records are stored in the log when storage operations are completed. Upon restarting an embodiment of the data storage system, the transaction records from the transaction logs are replayed to recreate the state of the data storage system. The data storage system updates file system metadata with transaction information while a storage operation associated with the file is being processed. This transaction information serves as atomically updated transaction commit points, allowing fully internally consistent snapshots of deduplicated volumes to be taken at any time.

Abstract: Embodiments provide systems, methods, and computer program products for tracking objects within a domain and their possible changes and genealogy over time. An object identifier and an interval identifier are associated with an object that enters the domain with an unknown set of attributes and genealogy. The object identifier is analyzed to determine whether it is a pre-existing object identifier. A comparison of the interval identifier is performed to determine whether the object is a copy of a prior object. The object identifier is replaced with a new object identifier and the interval identifier reset when the object is new or a copy. Based on the object identifier and the interval identifier, which represents the possibility of change during each interval, information about the tracked object may be derived and analyzed to enhance performance.

Abstract: Systems and techniques are described for optimizing secure communications. A client can use an authentication protocol, e.g., Kerberos, to authenticate with the server. Specifically, the client can obtain a service ticket from a ticket granting server, and then use the service ticket to authenticate with the server. The server can respond by providing an encrypted session key. The session key can then be used by the client and server to securely communicate with each other. A wide area network (WAN) optimization device described in this disclosure is capable of obtaining the session key without decrypting the service ticket. Specifically, the WAN optimization device can use information other than the service ticket to obtain the session key.

Abstract: An application monitoring system autonomously selects routines for performance monitoring based on characteristics of the content of the routines. These characteristics are preferably related to aspects of routines that are likely candidates for performance improvement, such as repetitive loops, event waits, synchronized blocks, and on. Routines that appear to be relatively un-improvable are excluded from initial monitoring, and routines that are subsequently determined to be relatively un-improvable, based on performance analysis and/or user feedback, are excluded from future monitoring. The determination of each routine's candidacy for monitoring is maintained over time, so that each subsequent monitoring session need not repeat the determinations. Changed routines are routinely re-monitored and/or re-assessed to affirm or modify the routine's candidacy for subsequent monitoring.

Abstract: In a network supporting transactions between clients and servers and proxies that are interposable in a network path, a pair of proxies can modify a packet stream such that packet data from client to server is transformed at a client-side proxy of the pair and untransformed at a server-side of the pair and packet data from server to client is transformed at the server-side proxy and untransformed at the client-side proxy. A discovering proxy transparently discovers its position in a proxy pair by using proxy signals. A discovering proxy might determine that it is a client-side proxy by receipt of a packet from client without a proxy signal, or that it is a server-side proxy by receipt of a packet from server without a return proxy signal. Once a proxy pair is discovered, it might transform traffic from server to client or vice versa, transforming and untransforming the traffic.

Abstract: Embodiments provide systems, methods, and computer program products for mapping higher-layer circuits, links, flows, and services to lower layer circuit and connection elements to determine utilization of the lower layer circuit elements based on the high-layer traffic. Higher layer configuration data and lower layer configuration data are imported to populate a model. An inter-layer relationship is either directly or indirectly mapped from the higher layers to the lower layer. Once the inter-layer relationship is established, the higher-layer circuits, links, flows, and services are inspected using the lower layer circuit and connection elements. Circuit and packet-based utilization is determined for the lower layer elements based on the higher-layer traffic flows.

Abstract: Embodiments provide methods for managing data generated by software transactions, such as event tracing software. In one embodiment, data generated by event tracing software is monitored. The throughput of the data generated may then be modulated based on various criteria, such as a target data rate. The throughput target may be specified on a per-system basis or individual basis. Based on the throughput, the level of detail recorded is modulated. Individual processes may determine a limit or quota depending on their contribution to the throughput. In one embodiment, the method calls for a trace are modified with different property specifications to meet a desired throughput of event tracing data.

Abstract: A system of network proxies distributes data to multiple servers. Each network proxy is associated with a server. A network proxy intercepts a client request for data. If the network proxy determines that the request can be served using a copy of data stored on the local server, rather than the data stored on a remote server, it diverts the request to the local server. If the network proxy determines that the request cannot be served using a data from the local server, the network proxy diverts the request to a remote server storing the primary copy of the data. A server map specifies the locations of the primary copies of data. When a primary copy of data is updated on one of the servers, the associated network proxy propagates the updated data to the other servers. The servers can provide data from files, e-mail services, databases, or multimedia services.

Abstract: 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.

Abstract: The performance of a monitored system is profiled based on sampling a portion of its operations. In one embodiment, the monitored system allocates memory for objects created as instances of classes and automatically performs regular garbage collection to reclaim memory. A variety of sampling techniques are used to minimize the impact on the performance of the monitored system. Characteristic memory utilization patterns can then be estimated for classes based on the samples. The patterns may be presented to a user for review and analysis. Characteristics of the monitored system's performance may be presented in an interactive interface that allows the user to trace the cause of the presented memory utilization patterns, and provides statistics regarding memory allocation and release to guide the user in this analysis.

Abstract: 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.