Accuracy versus efficiency of hyper-exponential approximations of the response time distribution of MMPP/M/1 queues

Paolo Romano, Bruno Ciciani, Andrea Santoro, Francesco Quaglia

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1 Citation (Scopus)


The Markov-Modulated Poisson Process (MMPP) has been shown to well describe the flow of incoming traffic in networked systems, such as the Grid and the WWW. This makes the MMPP/M/1 queue a valuable instrument to evaluate and predict the service level of networked servers. In a recent work, we have provided an approximate solution for the response time distribution of the MMPP/M/1 queue, based on a weighted superposition of M/M/1 queues (i.e. a hyper-exponential process). In this article, we address the tradeoff between the accuracy of this approximation and its computational cost. By jointly considering both accuracy and cost, we identify the scenarios where such approximate solution could be effectively used in support of network servers (dynamic) configuration and evaluation strategies aimed at ensuring agreed dependability levels in case of, e.g. request redirection due to faults. Finally, the effectiveness of the proposed approximate solution method is evaluated for a real-world case study relying on a trace-based traffic characterisation of a Grid server.
Original languageEnglish
Pages (from-to)107 - 125
Number of pages19
JournalInternational Journal of Parallel, Emergent and Distributed Systems
Issue number2
Publication statusPublished - Apr 2009
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Software
  • Computer Networks and Communications

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