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Paper: Simulation without the Artificial Abort: Simplified Proof and Improved Concrete Security for Waters' IBE Scheme

Authors:
Mihir Bellare
Thomas Ristenpart
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URL: http://eprint.iacr.org/2009/084
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Abstract: Waters' variant of the Boneh-Boyen IBE scheme is attractive because of its efficency, applications, and security attributes,but suffers from a relatively complex proof with poor concrete security. This is due in part to the proof's ``artificial abort'' step, which has then been inherited by numerous derivative works. It has often been asked whether this step is necessary. We show that it is not, providing a new proof that eliminates this step. The new proof is not only simpler than the original one but offers better concrete security for important ranges of the parameters. As a result, one can securely use smaller groups, resulting in significant efficiency improvements.
BibTeX
@misc{eprint-2009-18195,
  title={Simulation without the Artificial Abort:  Simplified Proof and Improved Concrete Security for Waters' IBE Scheme},
  booktitle={IACR Eprint archive},
  keywords={public-key cryptography / identity-based encryption},
  url={http://eprint.iacr.org/2009/084},
  note={To appear at Eurocrypt 2009 tristenp@cs.ucsd.edu 14292 received 17 Feb 2009},
  author={Mihir Bellare and Thomas Ristenpart},
  year=2009
}