Continuous Probabilistic Count Queries in Wireless Sensor Networks

• Author(s) / Creator(s)

  • Renz, Matthias
  • Kriegel, Hans-Peter
  • Nascimento, Mario A.
  • Follmann, Anna
  • Kroeger, Peer
  • Zuefle, Andreas

• Technical report TR10-09. Count queries in wireless sensor networks report the number of sensor nodes for which the measured values satisfy a given query predicate. However, measurements in wireless sensor networks are typically imprecise due to limited accuracy of the sensor hardware or fluctuations in the observed environment. Consequently, queries performed on these imprecise information implicate imprecise answers. In this paper, we study the problem of computing continuous probabilistic count queries in a distributed system, i.e., given a query Q we compute a probability distribution over the number of sensors satisfying Q's predicate. Such queries enables us to compute the probability that exactly, at most or at least k nodes satisfy Q. We investigate four algorithms that efficiently compute probabilistic count queries in a centralized manner as well as in-network and/or incrementally. In our performance evaluation we investigate all proposed algorithms in terms of the number of sent messages and show that our incremental approach is able to produce up to 80% less message transfers compared to the centralized algorithm. | TRID-ID TR10-09

• Date created

  2010

• Subjects / Keywords

  • Database Systems

• Type of Item

  Report

• DOI

  https://doi.org/10.7939/R30000147

• License

  Attribution 3.0 International