Privacy of encrypted voice-over-IP Conference Paper uri icon


  • In this paper, we present an early study on how timing-based traffic analysis attacks can be used to reconstruct the communication on end-to-end VOIP systems by taking advantage of the reduction or suppression of the generation of traffic whenever the sender detects a voice inactivity period. We describe a simple Bayesian classifier to identify simple voice signals from the pattern of packet timings. We then proceed to incorporate context awareness by using a Hidden Markov model. Experiments with very simple symbols show that the effectiveness to reconstruct the voice signal depends significantly on the quality of collected silence suppression information. We conclude by identifying a number of problems that need to be further studied in order to effectively assess the danger of silence suppression based attacks on VOIP systems. 2007 IEEE.

name of conference

  • 2007 IEEE International Conference on Systems, Man and Cybernetics

published proceedings

  • 2007 IEEE International Conference on Systems, Man and Cybernetics

author list (cited authors)

  • Lella, T., & Bettati, R.

citation count

  • 3

complete list of authors

  • Lella, Tuneesh||Bettati, Riccardo

publication date

  • October 2007