Efficient Traceable digital signature scheme for server cluster

In server clusters, there are occasions where all the servers are allowed to sign messages on behalf of the whole cluster and manager can identify the signer at the same time. In this paper, we propose a new scheme called Traceable Certificate-Based Group Signature (TCBGS) which brings better efficiency, privacy and traceability. The scheme is constructed on elliptic curve discrete logarithm problem which decreases calculation, increases efficiency and security. Only one step are needed in signing and verifying, which is simple and efficient. With CA-certificates, all users can create secret keys on their own, communicate through open channel and join in the cluster dynamically. Meanwhile, signers can be identified by manager through opening the signature. The security and performance analysis shows that our scheme is more efficient and satisfies security requirement.