VALUETOOLS 2008
INTER-PERF 2008WNS2 2008MODENETS 2008GAMECOMM 2008SMCTOOLS 2008

    VALUETOOLS

    3rd International ICST Conference on Performance Evaluation Methodologies and Tools

    Welcome to Athens! On behalf of the whole organizing team, we wholeheartedly welcome you to the third installment of Valuetools, Valuetools 2008. The first two installments took place in Pisa (2006) and Nantes (2007). So, again, the conference is taking place in a city of rich cultural heritage. We…

    Welcome to Athens! On behalf of the whole organizing team, we wholeheartedly welcome you to the third installment of Valuetools, Valuetools 2008. The first two installments took place in Pisa (2006) and Nantes (2007). So, again, the conference is taking place in a city of rich cultural heritage. We look forward to emulating the previous two installments also in terms of their scientific success. The motivation behind Valuetools is the observation that an impressive range of methodologies and tools have been developed recently for the purpose of performance evaluation, across many disparate research fields. Valuetools is meant to be a forum that will allow researchers to compare and debate the full range of these tools and methodologies, and in addition promote the interdisciplinary flow of technical information.

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    Editor(s): John Baras and Costas Courcoubetis
    Publisher
    ICST
    ISBN
    978-963-9799-31-8
    Conference dates
    20th–24th Oct 2008
    Location
    Athens, Greece
    Appeared in EUDL
    29th Nov 2011
    Appears in
    ACM Digital Library

    Copyright © 2011–2013 ICST

    • Simulation of wireless multi-* networks in NS-2

      Research Article in 3rd International ICST Conference on Performance Evaluation Methodologies and Tools

      Laurent Paquereau, Bjarne E. Helvik

      Abstract
      Multi-technology, multi-homed, multi-hop, multi-interface, multi-channel, multi-route, multi-destination etc. Emerging wireless networks are multi-* networks. Emerging wireless networks are also no l…Multi-technology, multi-homed, multi-hop, multi-interface, multi-channel, multi-route, multi-destination etc. Emerging wireless networks are multi-* networks. Emerging wireless networks are also no longer stand-alone and self-contained networks but connected to external networks. Simulating such complex systems requires advanced network simulation tools. The network simulator 2 (ns-2) is one of the most widely used simulators and has constantly been enriched to design, test and evaluate new network architectures and protocols. This paper motivates and presents the design and implementation of a network layer architecture that extends the functionality of ns-2 to support the aforementioned features. In particular, it provides support for multiple interfaces, potentially of different types, and multiple routing and forwarding protocols running on the same node.
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    • First-passage times in confined geometrys

      Research Article in 3rd International ICST Conference on Performance Evaluation Methodologies and Tools

      Olivier Bénichou, Sylvain Condamin , Vincent Tejedor , Raphael Voituriez , Joseph Klafter

      Abstract
      How long does it take a random walker to reach a given target point? This quantity, known as a first passage time (FPT), has led to a growing number of theoretical investigations over the last decade…How long does it take a random walker to reach a given target point? This quantity, known as a first passage time (FPT), has led to a growing number of theoretical investigations over the last decade. The importance of FPTs originates from the crucial role played by first encounter properties in various real situations, including transport in disordered media, spreading of diseases or target search processes. Most methods to determine the FPT properties in confining domains have been limited to effective 1D geometries, or for space dimensions larger than one only to homogeneous media. I will propose here a general theory which allows one to evaluate the mean FPT (MFPT) in complex media. This analytical approach provides a universal scaling dependence of the MFPT on both the volume of the confining domain and the source-target distance. This analysis is applicable to representative models of transport in disordered media, fractals, and anomalous diffusion.
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    • Lorenzian analysis of infinite poissonian populations and the phenomena of Paretian ubiquity

      Research Article in 3rd International ICST Conference on Performance Evaluation Methodologies and Tools

      Iddo Eliazar

      Abstract
      The Lorenz curve is a universally-calibrated statistical tool measuring quantitatively the distribution of wealth within human populations. We consider infinite random populations modeled by inhomoge…The Lorenz curve is a universally-calibrated statistical tool measuring quantitatively the distribution of wealth within human populations. We consider infinite random populations modeled by inhomogeneous Poisson processes defined on the positive half-line - the randomly scattered process-points representing the wealth of the population-members (or any other positive-valued measure of interest such as size, mass, energy, etc.). For these populations the notion of "macroscopic Lorenz curve" is defined and analyzed, and the notion of "Lorenzian fractality" is defined and characterized. We show that the only non-degenerate macroscopically observable Lorenz curves are power-laws manifesting Paretian statistics - thus providing a universal "Lorenzian explanation" to the ubiquitous appearance of Paretian probability laws in nature.
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    • From solar flare time series to fractional dynamics

      Research Article in 3rd International ICST Conference on Performance Evaluation Methodologies and Tools

      Krzysztof Burnecki , Aleksander Weron, Joseph Klafter, Marcin Magdziarz

      Abstract
      We demonstrate that continuous-time FARIMA processes with alpha-stable noise provide a new stochastic tool for studying the solar flare phenomenon in the framework of fractional Langevin equation. Si…We demonstrate that continuous-time FARIMA processes with alpha-stable noise provide a new stochastic tool for studying the solar flare phenomenon in the framework of fractional Langevin equation. Simple computer tests to check the origins of alpha-stability and self-similarity are implemented for empirical time series describing the energy of solar flares. Based on observed physical time series we solve the challenging problem of how to detect long-range dependence from real data and how to model it via fractional dynamics (Langevin or Fokker-Planck). We employ here codifference as a proper measure for long-range dependence. It is applicable to empirical data from the distribution lacking the second moment.
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    • Nonergodicity mimicking inhomogeneity in single particle tracking

      Research Article in 3rd International ICST Conference on Performance Evaluation Methodologies and Tools

      Igor Sokolov, Ariel Lubelski, Joseph Klafter

      Abstract
      Most statistical theories of anomalous diffusion rely on ensemble-averaged quantities such as the mean squared displacement. Recent single molecule tracking measurements require, however, temporal av…Most statistical theories of anomalous diffusion rely on ensemble-averaged quantities such as the mean squared displacement. Recent single molecule tracking measurements require, however, temporal averaging. We contrast the two approaches in the case of continuous-time random walks with an asymptotic power law distribution of waiting times lacking the mean. We show, that contrary to what is expected, the mean squared displacement obtained as a moving temporal average along the single trajectory, exhibits a simple diffusive behavior with diffusion coefficients which strongly differ from one trajectory to another. This finding mimics the inhomogeneous behavior as in an ensemble of random walkers with different diffusion coefficients. The information about the anomaly can be restored by an additional ensemble average over these diffusion coefficients, which results in an effective diffusion-coefficient which depends on the length of the trajectory T and on the exponent of the waiting time distribution.
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