A Parsimonious Multifractal Model for WWW Traffic
In this paper, we capture the main characteristics of WWW traffic in a stochastic model, which can be used to generate synthetic WWW traces and assess WWW cache designs. To capture temporal and spatial localities, we use a modified version of Riedi et al.’s multifractal model , where we reduce the complexity of the original model from O(N) to O(1); N being the length of the synthetic trace. Our model has the attractiveness of being parsimonious and that it avoids the need to apply a transformation to a self-similar model (as often done in previously proposed models ), thus retaining the temporal locality of the fitted traffic. Furthermore, because of the scale-dependent nature of multifractal processes, the proposed model is more flexible than monofractal models in describing irregularities in the traffic. Trace-driven simulations are used to demonstrate the goodness of the proposed model.
keywordsWWW modeling web caching multifractals stack distance self-similarity
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