Paper 2007/100
Practical Identity-Based Encryption (IBE) in Multiple PKG Environments and Its Applications
Shengbao Wang and Zhenfu Cao
Abstract
Identity-based encryption (IBE) schemes are usually used in multiple-PKG environments --- on the one hand, each administrative domain (e.g., a relatively small and close organization) maintains its own private key generator (PKG); on the other hand, encryption across domains becomes a prevalent requirement. In this paper, we present a new IBE scheme using bilinear pairings. Compared with the famous IBE scheme of Boneh and Franklin, we show that ours is more practical in the multiple-PKG environment. We prove that our scheme meets chosen ciphertext security in the random oracle model, assuming the intractability of the standard Bilinear Diffie-Hellman (BDH) problem. As an application of our IBE scheme, we also propose an escrowed ElGamal scheme which possesses certain good properties in practice.
Note: Thanks to a novel technique for simulating the H_1 oracle (due to Lal and Sharma, on page 6 of [LS07], which is adapted in our proof for Lemma 2) the IND-ID-CCA security of the full M-IBE scheme is now reduced to the standard BDH problem.
Metadata
- Available format(s)
-
PDF
PS
- Publication info
- Published elsewhere. In submission
- Keywords
- identity-based encryption (IBE)multiple-PKG environmentspublic key encryption (PKE)escrowed ElGamalbilinear pairings
- Contact author(s)
- shengbaowang @ gmail com
- History
- 2007-11-26: last of 2 revisions
- 2007-03-22: received
- See all versions
- Short URL
- https://ia.cr/2007/100
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2007/100,
author = {Shengbao Wang and Zhenfu Cao},
title = {Practical Identity-Based Encryption ({IBE}) in Multiple {PKG} Environments and Its Applications},
howpublished = {Cryptology {ePrint} Archive, Paper 2007/100},
year = {2007},
url = {https://eprint.iacr.org/2007/100}
}
