Alva L. Couch

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Despite its simplicity and its linear time, a serial K-means algorithm's time complexity remains expensive when it is applied to a problem of large size of multidimensional vectors. In this paper we show an improvement by a factor of O(K/2), where K is the number of desired clusters, by applying theories of parallel computing to the algorithm. In addition(More)
Current self-healing systems are built from “convergent” actions that only make repairs when necessary. Using an algebraic model of system administration, we challenge the traditional notion of “convergence” and propose a stronger definition with improved algebraic properties. Under the new definition, the structure of traditional configuration management(More)
We present a new model of configuration management based upon a hierarchy of simple communicating autonomous agents. Each of these agents is responsible for a ‘‘closure’’: a domain of ‘‘semantic predictability’’ in which declarative commands to the agent have a simple, persistent, portable, and documented effect upon subsequent observable behavior. Closures(More)
The process of network debugging is commonly guided by ‘‘decision trees,’’ that describe and attempt to address the most common failure modes. We show that troubleshooting can be made more effective by converting decision trees into suites of ‘‘convergent’’ troubleshooting scripts that do not change network attributes unless these are out of compliance with(More)
In an ideal world, the system administrator would simply specify a complete model of system requirements and the system would automatically fulfill them. If requirements changed, or if the system deviated from requirements, the system would change itself to converge with requirements. Current specialized tools for convergent system administration already(More)
In large networks, heterogeneity in hardware, operating systems, user needs, and administrative responsibility often forms boundaries that inhibit sharing of information, expertise, and responsibility. These boundaries can divide networks into ‘feudal fiefdoms’ of administrators, each with a disjoint domain of responsibility. DISTR is an easy-to-use file(More)