Study on ring signature and its application

Ring signature is digital signature scheme with additional properties, ring signature does not need to set up a group for signing and thus it avoids the operation of adding or deleting group members when the signer group has to be changed. The superiority of ring signature makes it more applicable for signature schemes with dynamic signing group. In the paper, we presented an improved ring signature scheme based on elliptic curves cryptosystem. In the scheme, ring signatures generated by different members are indistinguishable and the change of signer members has no direct influence on private key and other parameters in ring signature system, so the scheme achieves dynamic managing of ring signature and singer group. The scheme avoids the relevance between the complexity of ring signature and the signer ring scale by independent system parameters, and thus it improves the efficiency of signature protocols and effectively prevents coalition attack and generalized signature forgery.