On the security of Jhanwar-Barua Identity-Based Encryption Scheme

Adrian G.  Schipor

Paper 2018/479

On the security of Jhanwar-Barua Identity-Based Encryption Scheme

Adrian G. Schipor

Abstract

In 2008, Jhanwar and Barua presented an improvement of the Boneh-Gentry-Hamburg (BGH) scheme. In addition to reducing the time complexity of the algorithm to find a solution of the equation $ax^2+Sy^2\equiv 1 \bmod n$, their scheme reduces the number of equations to be solved by combining existing solutions. Susilo et al. extended the Jhanwar-Barua scheme, reducing more the number of equations to be solved. This paper presents a security flaw that appears in both schemes and shows that they are not IND-ID-CPA secure.

Metadata

Available format(s): PDF
Category: Public-key cryptography
Publication info: Preprint. MINOR revision.
Keywords: identity based encryption ibe
Contact author(s): agschipor @ gmail com
History: 2018-05-23: received
Short URL: https://ia.cr/2018/479
License: CC BY

BibTeX

@misc{cryptoeprint:2018/479,
      author = {Adrian G.  Schipor},
      title = {On the security of Jhanwar-Barua Identity-Based Encryption Scheme},
      howpublished = {Cryptology {ePrint} Archive, Paper 2018/479},
      year = {2018},
      url = {https://eprint.iacr.org/2018/479}
}