Cryptology ePrint Archive: Report 2007/400

REMARKS ON IBE SCHEME OF WANG AND CAO

Sunder Lal and Priyam Sharma

Abstract: In this paper we analyze and find an anomaly in the security proof of the identity-based encryption (IBE) scheme fullM-IBE of Wang and Cao [9], which is based on mBDHP. Here we give another proof for fullM-IBE which is based on Bilinear Diffie-Hellman Problem (BDHP). We also obtain a tightness improvement using a stronger assumption, namely, the Bilinear Inverse Dicision Diffie-Hellman problem (BIDDHP).

Category / Keywords: public-key cryptography / Public-Key Encryption, Identity-Based Encryption (IBE), IND-ID-CCA attack, BDHP, BIDDHP, Random Oracle.

Date: received 15 Oct 2007, last revised 13 Nov 2007

Contact author: sunder_lal2 at rediffmail com, priyam_sharma ibs@rediffmail com

Available formats: PDF | BibTeX Citation

Version: 20071114:053859 (All versions of this report)

Discussion forum: Show discussion | Start new discussion