The Automated Cryptanalysis of Analog Speech Scramblers

  • B Goldburg
  • E Dawson
  • S Sridharan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 547)


An automated method of attacking commonly used speech scramblers is presented. The cryptanalysis relies on the availability of the scrambled speech only and makes use of the characteristics of speech. It is shown that some of the currently available time and frequency domain scramblers, based on a fixed permutation, can be cryptanalysed. For systems where the permutation is changed with time, methods for partial recovery of the encrypted speech for several existing systems are given. In the case of the frequency domain scramblers a novel method of attack using a codebook is presented.


Intelligible Speech Attack Process Speech Frame Spectral Distance Codebook Vector 
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 1991

Authors and Affiliations

  • B Goldburg
    • 2
  • E Dawson
    • 1
  • S Sridharan
    • 2
  1. 1.School of Mathematics and Information Security Research CentreQueensland University of TechnologyBrisbaneAustralia
  2. 2.School of Electrical and Electronic Systems EngineeringQueensland University of TechnologyBrisbaneAustralia

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