General Certificateless Encryption and Timed-Release Encryption

  • Sherman S. M. Chow
  • Volker Roth
  • Eleanor G. Rieffel
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5229)


While recent timed-release encryption (TRE) schemes are implicitly supported by a certificateless encryption (CLE) mechanism, the security models of CLE and TRE differ and there is no generic transformation from a CLE to a TRE. This paper gives a generalized model for CLE that fulfills the requirements of TRE. This model is secure against adversaries with adaptive trapdoor extraction capabilities, decryption capabilities for arbitrary public keys, and partial decryption capabilities. It also supports hierarchical identifiers. We propose a concrete scheme under our generalized model and prove it secure without random oracles, yielding the first strongly-secure security-mediated CLE and the first TRE in the standard model. In addition, our technique of partial decryption is different from the previous approach.


Security-mediated certificateless encryption timed-release encryption standard model 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Sherman S. M. Chow
    • 1
  • Volker Roth
    • 2
  • Eleanor G. Rieffel
    • 2
  1. 1.Department of Computer Science Courant Institute of Mathematical SciencesNew York UniversityUSA
  2. 2.FX Palo Alto Laboratory Palo AltoUSA

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