On the Sequentiality of Three Optimal Structured Multisignature Schemes

摘要

A structured multisignature scheme is an order-sensitive multisignature scheme that allows participating signers to sign the same messages in compliance with a specified signing order. In this paper, we find that three optimal structured multisignature schemes cannot keep sequentiality since they cannot prevent partial signers producing a valid partial multisignature in a signing order different from the specified one. Hence, verifies cannot identify the real signing order only by checking verification equations. We guess that it is impossible to design any optimal structured multisignature scheme.