International Association for Cryptologic Research

International Association
for Cryptologic Research

CryptoDB

Efficient ID-based Signature Without Trusted PKG

Authors:
Jingwei Liu
Rong Sun
Weidong Kou
Xinmei Wang
Download:
URL: http://eprint.iacr.org/2007/135
Search ePrint
Search Google
Abstract: In this paper, we introduce the exact concept of ID-based signature without trusted Private Key Generator (PKG), which solves the key escrow problem through binding two partially public keys with a same identity. In this scheme, PKG is prevented from forging a legal user’s signature because he only generates the partially private key. Using Gap Diffie-Hellman (GDH) groups, we construct an efficient ID-based signature scheme without trusted PKG, which security relies on the hardness of the Computation Diffie-Hellman Problem (CDHP). More precisely, under the random oracle model, our scheme is proved to be secure against existential forgery on adaptively chosen message and ID attack, which is a natural ID-based version of the standard adaptively chosen message attack, assuming CDHP is intractable. Our scheme not only eliminates the inherent key escrow problem but also has a higher efficiency than the existing schemes.
BibTeX
@misc{eprint-2007-13417,
  title={Efficient ID-based Signature Without Trusted PKG},
  booktitle={IACR Eprint archive},
  keywords={public-key cryptography / ID-based Signature, Key Escrow, Gap Diffie-Hellman Group, Bilinear Pairing, Dishonest PKG},
  url={http://eprint.iacr.org/2007/135},
  note={has NOT been published elsewhere jwliu@mail.xidian.edu.cn 13621 received 17 Apr 2007},
  author={Jingwei Liu and Rong Sun and Weidong Kou and Xinmei Wang},
  year=2007
}