A Proxy Ring Signature Scheme with Revocable Anonymity Based on Bilinear Pairings

Abstract

The concept of ring signature was first introduced by Rivest et al. in 2001. In a ring signature, instead of revealing the identity of the actual signer, it specifies a set of possible signers. The verifier can be convinced that the signature was indeed generated by one of the ring members. However, the verifier can not tell which member actually produced the signature. Proxy ring signature allows proxy signer to sign messages on behalf of the original signer while providing unconditional anonymity. Proxy ring signature scheme with revocable anonymity allows the original signer to know exactly who the signer is and the original signer does not need to publish extra information except his original public key. Based on bilinear pairings, we present a proxy ring signature scheme with revocable anonymity was proposed. Formal security proof demonstrates that our proposed scheme satisfies the security requirements of unforgeability, unconditional anonymity for attackers except the original signer and revocable anonymity for the original signer. As the other existing proxy ring signature schemes with revocable anonymity are insecure, our proposed scheme is the first secure scheme of this sort.