An Efficient Identity Based Compact Multi-signature From RSA

A compact multi-signature is a special digital signature that allows multiple signers to generate a signature on the same message with the property that the length of the signature is almost same as that of an individual signature. An efficient identity based compact multi-signature scheme from RSA is proposed in this paper. The efficiency of the new scheme is improved by 50% than that of Bellare and Nevens scheme. The signature length of the new scheme is almost same as that of a single RSA signature, as the identity based public key is used, the goal to design a compact multi-signature is nearly achieved. The security of the new scheme is proved under the assumption of RSA in the random oracle model.