New Fuzzy Identity-Based Encryption in the Standard Model

Article type: Research Article

Authors: Ren, Yanli^; | Gu, Dawu | Wang, Shuozhong | Zhang, Xinpeng

Affiliations: Department of Computer Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China | School of Communications and Information Engineering, Shanghai University, Shanghai 200072, China, e-mail: [email protected], [email protected]

Abstract: In a fuzzy identity-based encryption (IBE) scheme, a user with the secret key for an identity ID is able to decrypt a ciphertext encrypted with another identity ID' if and only if ID and ID' are within a certain distance of each other as judged by some metric. Fuzzy IBE also allows to encrypt a document to all users that have a certain set of attributes. In 2005, Sahai and Waters first proposed the notion of fuzzy IBE and proved the security of their scheme under the selective-ID model. Currently, there is no fuzzy IBE scheme available that is fully CCA2 secure in the standard model. In this paper, we propose a new fuzzy IBE scheme which achieves IND-FID-CCA2 security in the standard model with a tight reduction. Moreover, the size of public parameters is independent of the number of attributes associated with an identity.

Keywords: cryptography, fuzzy identity-based encryption, IND-FID-CCA2 security, standard model

Journal: Informatica, vol. 21, no. 3, pp. 393-407, 2010