The ring signature with adaptability

[[abstract]]The concept of ring signature was first introduced by Rivest et al. in 2001. Instead of revealing the actual identity of the message signer, it specifies a set of possible signers (ring members). The generated ring signature can convince any verifier that the message was indeed signed by one of the ring members; however, the real signer’s identity is totally anonymous to the verifier. However, in some applications, the actual signer may like to reduce the number of ring members of an existent ring signature. For instance, suppose that Bob is a member of the cabinet, and that Bob wishes to leak a juicy fact to a journalist. Then, Bob can send the story to the journalist through a ring signature scheme that names each cabinet member as a ring member. However, if Bob want to reduce the scale of the ring members by revealing further information about himself, such as gender, political party, regionalism… etc, then Bob cannot but construct a newly ring signature for the second time. The goal of this study is to embed the concept of adaptability into the ordinary ring signature system based on the Elliptic Curve Cryptography, and in the course of so, maintain the level of security. We believe it is highly feasible to construct a transformation model for the original ring signer to reduce its ring members instead of spending more effort to reconstruct a newly signature. Therefore, this model can be put on many deployed popular ring signature applications directly and provide the benefits inherited from the adaptability. Thus, we thought that this study is important and ought to be highly regarded