An identity-based proxy re-encryption scheme with source hiding property, and its application to a mailing-list system

Abstract

Identity-Based Proxy Re-Encryption (IB-PRE) has been proposed by Green and Ateniese (ACNS2007), where the proxy transforms a source ciphertext encrypted by a delegator's identity into a destination ciphertext that can be decrypted using a delegatee's secret key corresponding to the delegatee's identity. By using IB-PRE, we expect that mailing-list systems can be constructed without public key certificates. However, in all previous IB-PRE, information about whether a source ciphertext (encrypted by a mailing-list address) is the source of a destination ciphertext (encrypted by an e-mail address) or not, is revealed from both the source ciphertext and the destination ciphertext. In this paper, for the first time we propose an IB-PRE scheme with source hiding property, where no information about source identity is revealed from the destination ciphertext. Our work is the valuable and important milestone for establishing the secure PRE-based mailing-list system without public key certificates. © 2011 Springer-Verlag.