Ring Signature Scheme Research Articles

A Certificateless Ring Signature Scheme with High Efficiency in the Random Oracle Model

Ring signature is a kind of digital signature which can protect the identity of the signer. Certificateless public key cryptography not only overcomes key escrow problem but also does not lose some advantages of identity-based cryptography. Certificateless ring signature integrates ring signature with certificateless public key cryptography. In this paper, we propose an efficient certificateless ring signature; it has only three bilinear pairing operations in the verify algorithm. The scheme is proved to be unforgeable in the random oracle model.

An Efficient Code-Based Threshold Ring Signature Scheme with a Leader-Participant Model

Digital signature schemes with additional properties have broad applications, such as in protecting the identity of signers allowing a signer to anonymously sign a message in a group of signers (also known as a ring). While these number-theoretic problems are still secure at the time of this research, the situation could change with advances in quantum computing. There is a pressing need to design PKC schemes that are secure against quantum attacks. In this paper, we propose a novel code-based threshold ring signature scheme with a leader-participant model. A leader is appointed, who chooses some shared parameters for other signers to participate in the signing process. This leader-participant model enhances the performance because every participant including the leader could execute the decoding algorithm (as a part of signing process) upon receiving the shared parameters from the leader. The time complexity of our scheme is close to Courtois et al.’s (2001) scheme. The latter is often used as a basis to construct other types of code-based signature schemes. Moreover, as a threshold ring signature scheme, our scheme is as efficient as the normal code-based ring signature.

Efficient ring signature schemes over NTRU Lattices

AbstractTwo ring signature schemes over number theory research unit (NTRU) lattices are presented. The first scheme constructed in the random oracle model is an extension of Ducas, Lyubashevsky, and Prest's identity‐based encryption scheme over NTRU lattices (in Asiacrypt 2014). Moreover, motivated by Boyen's lattice mixing and vanishing trapdoors (in PKC 2010), the second scheme in the standard model is achieved. Under the chosen‐message attack, our new constructions are proved strongly existentially unforgeable, and the security can be reduced to the hardness of NTRU lattices. Compared with the existing lattice‐based ring signatures, our schemes are more efficient and with shorter signature length. Copyright © 2016 John Wiley & Sons, Ltd.

Insecurity of a Certificate-free Ad Hoc Anonymous Authentication

The ring signature scheme is a simplified group signature scheme for no manager while preserving unconditionally anonymous of the signer. Certificateless cryptography is introduced for eliminating the use of certificates in Public Key Infrastructure and solving the key-escrow problem in ID-based cryptogratography. Recently, Qin et al. proposed the first RSA-based certificateless ring signature scheme which was proved unforgeable in random oracle model. In this paper, we demonstrated that this scheme was not secure against the Type I adversary.

A Research Survey of Ring Signature Scheme and Implementation Issues

A Research Survey of Ring Signature Scheme and Implementation Issues

Improved lattice-based ring signature schemes from basis delegation

Ring signature enables the members to sign anonymously without a manager, it has many online applications, such as e-voting, e-money, whistle blowing etc. As a promising post-quantum candidate, lattice-based cryptography attracts much attention recently. Several efficient lattice-based ring signatures have been naturally constructed from lattice basis delegation, but all of them have large verification key sizes. Our observation finds that a new concept called the split-small integer solution (SIS) problem introduced by Nguyen et al. at PKC'15 is excellent in reducing the public key sizes of lattice-based ring signature schemes from basis delegation. In this research, we first define an extended concept called the extended split-SIS problem, and then prove that the hardness of the extended problem is as hard as the approximating shortest independent vectors problem (SIVP) problem within certain polynomial factor. Moreover, we present an improved ring signature and prove that it is anonymous and unforgeable against the insider corruption. Finally, we give two other improved existing ring signature schemes from lattices. In the end, we show the comparison with the original scheme in terms of the verification key sizes. Our research data illustrate that the public key sizes of the proposed schemes are reduced significantly.

Refined Shacham–Waters ring signature scheme in Seo–Cheon framework

AbstractComposite order bilinear groups have some elegant structural characteristics that are useful in constructing advanced cryptographic schemes. However, they are computationally less efficient than their prime order counterparts thereby making them impractical. Thus, instantiating cryptographic schemes based on composite order bilinear groups in prime order setting while preserving all the structural properties has become an attractive area of research. Freeman identified two main properties, namely, projecting and cancelling that are useful in such conversions. Seo and Cheon constructed an asymmetric bilinear‐group generator that is both projecting and cancelling in the prime order setting. Nonetheless, for this special generator, they could not find any useful cryptographic application.In this work, we instantiate Shacham–Waters ring signature scheme in the prime order setting. We emphasize that the converted scheme is instantiated in asymmetric setting. It is both elegant and efficient. Interestingly, with this conversion, we present the first cryptographic scheme based on the Seo–Cheon asymmetric bilinear‐group generator. We also observe that the Seo–Cheon definition of translating needs to be more specific, otherwise computational Deffie–Hellman problem becomes easy in general. We comment on standard ways for making the converted scheme more efficient in terms of computation and signature length. Copyright © 2016 John Wiley & Sons, Ltd.

Logarithmic size ring signatures without random oracles

Ring signatures enable a user to anonymously sign a message on behalf of group of users. In this study, the authors propose the first ring signature scheme whose size is O(log2 N), where N is the number of users in the ring. They achieve this result by improving Chandran et al.’s ring signature scheme presented at the International Colloquium on Automata, Languages and Programming 2007. Their scheme uses a common reference string and non-interactive zero-knowledge proofs. The security of their scheme is proven without requiring random oracles.

Unconditionally Anonymous Controllable ID-Based Ring Signatures

ID-Based ring signatures are result of application of ID-Based cryptosystems to ring signature schemes. The contribution of this paper is twofold. At first the paper introduces a new variant of ID-based ring signatures named as controllable ID-Based ring signatures (CIBRS). This new primitive has additional properties like control linkability, anonymous authorship and convertibility. Formal definitions of these properties and the security model for the new primitive were presented. Secondly, the paper presents the first unconditionally anonymous CIBRS scheme from Chow et al.’s [4] scheme. The proposed scheme uses control linkability to achieve high efficiency of computation and storage. In the proposed scheme, to generate k signatures, a member of an n-member-ring needs only n+k scalar point multiplications and 2n+k-1 hash computations when compared to kn operations of Chow et al.’s scheme. Also, to verify k signatures the scheme requires only 2 pairing operations and n+k-1 hash computations compared to 2k and nk operations respectively. Link-signatures due to the proposed scheme are independent of size of the ring. Using the link-signatures our scheme achieves a significant signature size of 3(n+k)-1 compared to 2k(n+1) (in the units of size of the field element). The scheme provides unconditional anonymity and uncontrollability to the signer even in case of compromise of the key-escrow.

Certificateless ring signature based on RSA problem and DL problem

Certificateless public key cryptography solves the certificate management problem in the traditional public key cryptography and the key escrow problem in identity-based cryptography. RSA is a key cryptography technique and provides various interfaces for the applied software in real-life scenarios. To the best of our knowledge, all of the known certificateless ring signature schemes employed bilinear pairings. But the computation cost of the pairings is much higher than that of the exponentiation in a RSA group. In this paper, we present the first certificateless ring signature scheme without pairing and prove the security in the random oracle model. The security of the scheme is closely related to the RSA problem and the discrete logarithm (DL) problem.

Identity-based quotable ring signature

We present a new notion of identity-based quotable ring signature. This new cryptographic primitive can be used to derive new ring signatures on substrings of an original message from an original ring signature on the original message, which is generated by the actual signer included in the ring. No matter whether a ring signature is originally generated or is quoted from another valid ring signature, it will convince the verifier that it is generated by one of the ring members, without revealing any information about which ring member is the actual signer. The set of ring members could be arbitrarily selected by the actual signer without need of other ring members’ approval. The actual signer is anonymous among this set of ring members. At the same time, the verifier could not distinguish whether a ring signature is originally generated or is quoted from another ring signature. In this paper, we propose a concrete identity-based quotable ring signature scheme based on bilinear pairing. We make use of bilinear groups of composite order. The construction is identity-based to alleviate the problem of certificate verification, especially for applications involving a large number of public keys in each execution such as ring signature schemes. The proposed scheme is proven to be anonymous under the assumption that the Subgroup Decision Problem is hard, selectively unforgeable against adaptively chosen message attacks in the random oracle model under the assumption that the Computational Diffie–Hellman problem is hard, and strongly context hiding.

A Survey on Security and Privacy in Wireless Sensor Network

Over the past few years, the concern of security is increasing day by day. Without proper protection, any part of any network can be susceptible to attacks or unauthorized activity. Ring Signature is a type of digital signature that enable a user to sign a message so that ring of possible signers is identified without revealing exactly which member of that ring actually generated the signature. Ring signatures are completely ad-hoc in nature there is no requirement of any central authority or coordination among different users. In this paper, we review summarize the study of ring signature schemes and scrutinize their relationships with other existing cryptographic schemes and discuss the uses and the mechanism used by ring signature.

An efficient ring signature scheme from pairings

Ring signature is a group-oriented signature with privacy concerns: any verifier can be convinced that the message has been signed by one of the members in the group, but the actual signer remains unknown. Several ring signature schemes based on bilinear pairings have been proposed. However, computational complexity for pairing computations of these ring signature schemes grows linearly with the size of the ring. In this paper, we propose an efficient ring signature with constant pairing computations and give its exact security proofs in the random oracle model under the Computational co-Diffie–Hellman assumption. We then investigate the performance of our scheme by choosing the Optimal-Ate pairing on the BN curve defined over a prime field at a 128-bit security level.

Identity-based strong designate verifier signature over lattices

The notion of the identity-based (id-based) strong designate verifier signature (SDVS) was extent to the lattice-based cryptography. The authors proposed an id-based SDVS scheme over lattices by using the basis delegation technical in fixed dimension. The proposed scheme is based on the hardness of the learning with errors (LWE) problem, and the unforgeability against adaptive chosen message and selective identity attack is based on the hardness of the short integer solution (SIS) problem in the random oracle model. If the parameters m, n and q are the same, the signature length of this scheme is only 3mlbq bits shorter than (3m+n)lb q bits which is the signature length of the known lattice-based SDVS scheme in the public key environment. As a result, the proposed scheme is not only id-based but also efficient about the signature length and the computation cost. Moreover, this article also proposed an id-based strong designate verifier ring signature (SDVRS) scheme based on the proposed SDVS scheme, which satisfies anonimity, unforgeability.

EIPS: An Efficient Identity-Based Ring Signature Scheme

As an important crypto graphical tool, ring signature is able to realize full anonymity and identity protection. Comparison the traditional PKI, Identity-based (ID-based) cryptography is a very good cryptosystem since it eliminates the need for checking the validity of the certificates of traditional public key system. In this work, we propose an efficient ring signature scheme by combining ID-based cryptography and Schnorr signature conception. Our scheme has some advantages for efficiency. In our proposed scheme, no pairing operators are needed in the whole signing phase and the verifying phase. It reduces the signer’s computation cost and increases the whole signature algorithm’s efficiency. In terms of signature’s length, our scheme only needs (n+1)|G| bits. Our ring signature can achieve full anonymity and unforgeability. The security of the scheme is related to two classical security assumptions: computational diffie-hellman problem and discrete logarithm problem.

A short identity-based proxy ring signature scheme from RSA

Identity-based proxy ring signature concept was introduced by Cheng et al. in 2004. This primitive is useful where the privacy of proxy signers is required. In this paper, the first short provably secure identity-based proxy ring signature scheme from RSA assumption has been proposed. In addition, the security of the proposed scheme tightly reduces to the RSA assumption, and therefore, the proposed scheme has a proper advantage in security reduction compared to the ones from RSA. The proposed scheme not only outperforms the existing schemes in terms of efficiency and practicality, but also does not suffer from the proxy key exposure attack due to the use of the sequential aggregation paradigm.

Collusion-resistant convertible ring signature schemes

A ring signature scheme provides signer ambiguity by hiding a signer in a ring of arbitrary members appropriately. A convertible ring signature scheme is an extension of a ring signature scheme that authenticates a signer and proves that a real signer and no one else generated a ring signature. In this paper, we first show that the recent convertible ring signature scheme proposed by Jeong et al. is vulnerable to collusion attacks. Second, we present a formal security model for a convertible ring signature with collusion resistance. The security notion of a convertible ring signature is intrinsically different from that of an ordinary ring signature due to the conversion property. For our collusion resistance, we consider full key exposure, that is, even an adversary who knows all secret keys will not be able to break the collusion resistance. Finally, we construct a novel convertible ring signature scheme with collusion resistance and prove the security of the scheme in the presented security model. We also compare our scheme with the existing ring signature schemes in the literature to show its advantages.

A provably secure identity‐based proxy ring signature based on RSA

AbstractProxy ring (anonymous proxy) signatures allow an entity to delegate its signing capability to a group of entities (proxy group) such that only one of the members in the proxy group can generate a proxy signature on behalf of the delegator, while privacy of the proxy signer is protected. Identity‐based versions of proxy ring signatures employ identity strings in place of randomly generated public keys. Our contribution is twofold. First, we formalize a security model for identity‐based proxy ring signatures. We note that there exists no formal security model for identity‐based proxy ring signatures prior to our work. Second, we present the first provably secure identity‐based proxy ring signature scheme using a new paradigm called sequential aggregation. The construction is proved secure, under the one‐wayness assumption of RSA, in the random oracle model by presenting a new forking lemma. We should highlight that the proxy key exposure attack cannot be applied to our scheme. Further, in contrast to the existing schemes that are based on pairings, our scheme is based on RSA; therefore, it outperforms the existing schemes in terms of efficiency and practicality. Copyright © 2014 John Wiley & Sons, Ltd.

A Provably secure Certificate based ring signature without pairing

In Eurocrypt 2003, Gentry introduced the notion of certificate-based encryption. The merit of certificate-based encryption lies in implicit certificate and no private key escrow. This feature is desirable especially for the efficiency and the real spontaneity of ring signature, which involve a large number of public keys in each execution. In this paper, we propose an efficient certificate-based ring signature scheme which does not require any pairing computation. Furthermore, this scheme is proven secure under the Discrete Logarithm assumption in the random oracle model. To the best of authors' knowledge, this is the first construction of certificate-based ring signature scheme in the literature that has such kind of feature.

A Privacy Preserving Communication Scheme for VANETs

In this paper, we propose a privacy preserving communication scheme for VANETs, combining ring signature and an identity based encryption. In our scheme, all the messages which needn't keep secret but provide authenticity is signed by employing a ring signature scheme, and it provide good anonymity. And we propose a approach that collecting and disseminating pks by the help of RSU. The vehicle encrypt its pk with the RSU's identity by using a IBE scheme and send it to the nearest RSU, the RSU collect pks and form a ring, and then broadcast it to the vehicles. All vehicles in this ring can sign messages with this the same ring.