Traceable signatures schemes were introduced by Kiayias, Tsiounis and Yung in order to solve traceability issues in group signature schemes. They wanted to enable authorities to delegate some of their detection capabilities to tracing sub-authorities. Instead of opening every single signatures and then threatening privacy, tracing sub-authorities are able to know if a signature was emitted by s...

In recent years one of the most active research areas in applied cryptography is the study of techniques for creating a group signature, a cryptographic primitive that can be used to implement anonymous authentication. Some variants of group signature, such as traceable signature, and authentication with variable anonymity in a trusted computing platform, have also been proposed. In this paper ...

<p>Anonymity is a necessary property for ring signature scheme and also its variant such as linkable traceable schemes, which are especially useful in blockchains. Intuitively, those variants were designed detecting or seeking the dishonest signatory, however, at cost of reducing anonymity traditional signature. As result, while various constructions strongly anonymous signatures well-kno...

In this paper, we introduce a new efficient technique allowing to render an off-line e-cash system traceable without need to a trusted party. The main idea is the use of the publicly verifiable secret sharing technique in order to revoke the anonymity of double spending users. The anonymity of honest users is still provided. Security analysis shows that the proposed technique does not undermine...

In order to protect the user's privacy identity, authentication requires anonymous authentication. Anonymous is divided into unconditional and traceable Unconditional can verify that user belongs an set, but true identity cannot be obtained. However, in some applications, it necessary trace of user. Therefore, a scheme proposed. prevent random tracing, proposed uses threshold joint tracing. Whe...

This paper introduces a new concept called controllable ring signature which is ring signature with additional properties as follow. (1) Anonymous identification: by an anonymous identification protocol, the real signer can anonymously prove his authorship of the ring signature to the verifier. And this proof is non-transferable. (2) Linkable signature: the real signer can generate an anonymous...

Blockchains allow users to transfer money securely to possibly unknown and untrusted counterparties, without requiring a trusted intermediary. Transactions contain the value being transferred, and sender and recipient identifiers (known as addresses) in the clear, meaning that although onchain addresses are unlinked from off-chain identities, monetary movements are easily traceable. We explore ...

Attribute based group signature (ABGS) is a a new generation of group signature schemes. In such a scheme the verifier could define the role of a signer within the group. He determines the attributes possessed by the member signing the document. In this paper we propose the first ABGS scheme with multi-authorities and define its security notions. We construct an ABGS that is proved to be fully ...

This paper introduces a new concept called controllable ring signature which is ring signature with additional properties as follow. (1) Anonymous identification: by an anonymous identification protocol, the real signer can anonymously prove his authorship of the ring signature to the verifier. And this proof is non-transferable. (2) Linkable signature: the real signer can generate an anonymous...

This paper introduces a new concept called controllable ring signature which is ring signature with additional properties as follow. (1) Anonymous identifica-tion: by an anonymous identification protocol, the real signer can anonymously prove his authorship of the ring signature to the verifier. And this proof is non-transferable. (2) Linkable signature: the real signer can generate an anonymou...