Sampling Bias in BitTorrent Measurements

  • Boxun Zhang
  • Alexandru Iosup
  • Johan Pouwelse
  • Dick Epema
  • Henk Sips
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6271)


Real-world measurements play an important role in understanding the characteristics and in improving the operation of BitTorrent, which is currently a popular Internet application. Much like measuring the Internet, the complexity and scale of the BitTorrent network make a single, complete measurement impractical. While a large number of measurements have already employed diverse sampling techniques to study parts of BitTorrent network, until now there exists no investigation of their sampling bias, that is, of their ability to objectively represent the characteristics of BitTorrent. In this work we present the first study of the sampling bias in BitTorrent measurements. We first introduce a novel taxonomy of sources of sampling bias in BitTorrent measurements. We then investigate the sampling among fifteen long-term BitTorrent measurements completed between 2004 and 2009, and find that different data sources and measurement techniques can lead to significantly different measurement results. Last, we formulate three recommendations to improve the design of future BitTorrent measurements, and estimate the cost of using these recommendations in practice.


Sampling Bias File Size Measurement Duration Trace Archive Data Source Selection 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2010

Authors and Affiliations

  • Boxun Zhang
    • 1
  • Alexandru Iosup
    • 1
  • Johan Pouwelse
    • 1
  • Dick Epema
    • 1
  • Henk Sips
    • 1
  1. 1.Parallel and Distributed Systems GroupDelft University of TechnologyDelftthe Netherlands

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