International Business Machines Corporation

Alina Beygelzimer

Irina Rish

Sheng Ma

Mudhakar Srivatsa

Dakshi Agrawal

Shang Qing Guo

Jonathan Lenchner

Mark N Wegman

Nianjun Zhou

Bong Jun Ko

Joseph L Hellerstein

Gerald James Tesauro

Richard B Segal

Irwin Boutboul

Mark Alan Brodie

Natalia V Odintsova

Herbert M Lee

Chang-shing Perng

Gaurav Chandalia

Bong-Jun Ko

A method, system and computer program product for choosing actions in a state of a planning problem. The system simulates one or more sequences of actions, state transitions and rewards starting from the current state of the planning problem. During the simulation of performing a given action in a given state, a data record is maintained of observed contextual state information, and observed cumulative reward resulting from the action. The system performs a regression fit on the data records, enabling estimation of expected reward as a function of contextual state. The estimations of expected rewards are used to guide the choice of actions during the simulations. Upon completion of all simulations, the top-level action which obtained highest mean reward during the simulations is recommended to be executed in the current state of the planning problem.

Monte-Carlo planning using contextual information

A method and system for generating problem resolution flowcharts, whereby users do not author flowcharts directly but instead author a dependency matrix of questions and answers related by state or underlying problem cause. After creation of a matrix of questions and answers, a corresponding flowchart is then calculated based on the information in the dependency matrix, and also based on the likelihood of the various problems and their causes. The probabilities of problems and their causes may be estimated or may be calculated from historical data accumulated by use of the flow chart, or some combination of the two. These probabilities are incorporated into the answer cells of the dependency matrix. The resulting flowchart is tested and evaluated, and the results of testing and evaluation are used to make modifications in the matrix of questions and answers. The flowchart is then made available for execution by a problem determination engine, usable by staff at a help center or directly as self-help to a customer over a network. Experience from use of the problem determination engine is accumulated for use in further refinements of the dependency matrix and its probabilities.

Method and apparatus for authoring and optimizing flowcharts

A method of determining the state of network links based on differences in corresponding distance-vectors in a sequence routing table updates, and a network management system performing the method. The network management system comprises least one monitoring apparatus adapted to determine the state of network links. The monitoring apparatus may be a router in the network adapted to determine link status, or a personal computer or server peered with a router and configured to determine the state of network links based on differences in corresponding distance-vectors in a sequence of routing table updates.

System and method for obtaining network link state information from sequential distance vector routing tables

A method for performance bottleneck diagnosis and dependency discovery in distributed systems and computer networks includes receiving a real-valued end-to-end measurement matrix, a number of end-to-end measurements, a number of time points, a number of network components, a loss function, and a plurality of constraints on output matrices. The method further includes learning basic output matrices by best approximation of a transpose of the real-valued end-to-end measurement matrix, selecting a first threshold based on a real-valued mixing-weights matrix and a second threshold based on a real-valued delay matrix, converting the real-valued mixing-weights matrix and the real-valued delay matrix into respective binary matrices using the first threshold and the second threshold, and returning the real-valued mixing-weights matrix, the real-valued delay matrix, and the respective binary matrices to represent bottlenecks dependencies of the distributed system or computer network.

Method for performance bottleneck diagnosis and dependency discovery in distributed systems and computer networks

A method and system for detecting and correcting invalid network paths in a network having a plurality of routers and a set of global invariant rules imbedded in the network including querying a subset of a routing table data structure defining network paths wherein said subset includes a plurality of routing table entries and comparing a network routing table entry with an earlier network routing table entry for the same node. The method and system also includes detecting inconsistencies between the newer network routing table entry and the earlier network routing table entry, and invalidating the network entries of the older network routing table that are inconsistent with the newer entries. The method and system also includes reconstructing the routing structure by replacing the invalidated network routing table entries with new routing table entries that minimize violation of the invariant protocols.

Method and system for deducing network routes by querying routers

Improved network topology discovery techniques. For example, an automated method for discovering a topology of a network, having a plurality of nodes, includes the following steps. A first traceroute process is performed for a given source node and one or more destination nodes listed in a target list so as to discover one or more paths through one or more intermediate nodes between the given source node and the one or more destination nodes. The one or more intermediate nodes discovered during the first traceroute process are added to the target list. A second traceroute process is performed for the given source node and the one or more intermediate nodes discovered during the first traceroute process so as to discover one or more paths through one or more additional intermediate nodes between the given source node and the one or more intermediate nodes discovered during the first traceroute process.

Method and apparatus for network topology discovery using closure approach

The invention concerns apparatus and methods that determine availability and performance of entities providing services in a distributed system using filtered service-consumer feedback. In particular, apparatus and methods of the invention filter service-consumer feedback in order to reduce the effect of circumstances unique to individual service consumers or to groups of service consumers that do not accurately reflect the actual availability or performance of service-providing entities. In this way an accurate appraisal is gained regarding the performance and availability of a service-providing entity. Reactive methods of the invention can be combined with proactive methods such as, for example, active status probing, to further improve the accuracy of data concerning the status and availability of service-providing entities.

Apparatus and methods for determining availability and performance of entities providing services in a distributed system using filtered service consumer feedback

Techniques for ordering categorical attributes so as to better visualize data are provided. In accordance with one embodiment of the invention, an ordering algorithm comprises the steps of: (a) translating the discrete ordering problem to a continuous optimization problem; (b) solving the continuous optimization problem; and (c) mapping an optimal continuous solution to the closest discrete solution.

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White Plains, NY, United States of America

Alina Beygelzimer