An Efficient Identity-Based Concurrent Signature Scheme

The concept of concurrent signature was first introduced by Chen, Kudla and Paterson in Eurocrypt´04, it contributes a novel approach for the traditional problem of fair exchange of signatures. Unfortunately we find out that in many concurrent signature schemes based on ring signatures, signers produced a signature, but his own cannot authenticate this signature was indeed produced by himself. To deal with this defect, in this paper, we proposed an efficient ID-based concurrent signature based on a ring signature scheme proposed by Zhang. It is a concurrent signature scheme with self-authenticating which can authenticate that a signer possesses a signature´s ownership. Finally, we discuss the performance of our signature.