Improved Anonymous Timed-Release Encryption

  • Konstantinos Chalkias
  • Dimitrios Hristu-Varsakelis
  • George Stephanides
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4734)


We revisit the problem of “sending information into the future” by proposing an anonymous, non-interactive, server-based Timed-Release Encryption (TRE) protocol. We improve upon recent approaches by Blake and Chan, Hwang et al., and Cathalo et al., by reducing the number of bilinear pairings that users must compute, and by enabling additional pre-computations. Our solution compares favorably with existing schemes in terms of computational efficiency, communication cost and memory requirements, and is secure in the random oracle model.


timed-release encryption bilinear pairings pre-computations multiple receivers 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2007

Authors and Affiliations

  • Konstantinos Chalkias
    • 1
  • Dimitrios Hristu-Varsakelis
    • 1
  • George Stephanides
    • 1
  1. 1.Computational Systems and Software Engineering Laboratory, Department of Applied Informatics, University of Macedonia, ThessalonikiGreece

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