A New Practical Limited Identity-Based Encryption Scheme

Article type: Research Article

Authors: Lu, Rongxing | Cao, Zhenfu | Dong, Xiaolei

Affiliations: Department of Computer Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, P.R. China. E-mail: [email protected]; {cao-zf,dong-xl}@cs.sjtu.edu.cn

Abstract: Identity based cryptography was introduced by Shamir in 1984, which avoids the trust problems encountered in the traditional Public Key Infrastructures. After Boneh and Franklin proposed the first full functional identity based encryption scheme from the bilinear pairings in 2001, many other identity based schemes using pairings have been proposed. However, how to design a practical identity based encryption scheme that avoids using the pairings is still an open problem today. In this paper, after studying and combining the advantages of the traditional public key system and identity based system, we formally define a new Limited identity based system and present a concrete Limited identity based encryption scheme on a different complexity assumption. The resulting scheme is not only provably secure against the chosen plaintext attack in the random oracle, but also especially suitable for some practical system, such as an email system.

Keywords: Identity based cryptography, Limited identity based encryption, Chosen-plaintext security, Email system

Journal: Fundamenta Informaticae, vol. 80, no. 4, pp. 461-474, 2007