Key Selection for Multilevel Indices of Large-Scale Service Repositories

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Conference Proceeding

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With the explosive growth of service-oriented computing (SOC) and extensive use of Web service technology, large amounts of services need to be efficiently stored and managed. Many works studied storage structures of services. Among them, a multilevel index model has been proved very efficient for service storage (including retrieval, addition and deletion etc.) in large-scale service repositories. A novel conception of “key” in the multilevel index model was used to remove much redundancy and speedup service retrieval significantly. But they did not discuss to what extent a key selection method can affect retrieval efficiency and whether it affects retrieval stability and addition efficiency. Focusing on these questions, our theoretical analysis and experiments proved that, in a multilevel index, different key selection methods cannot affect retrieval efficiency but do affect retrieval stability and addition efficiency. An improved key selection method is proposed. It saves nearly 50% addition time and reduces more than 80% instability (measured by standard deviation) without loss of retrieval efficiency.