ID-based Ring Signature Research Articles

Blockchain-assisted sharing of electronic health records: a feasible privacy-centric constant-size ring signature framework

The quest to share Electronic Heath Records (EHR) with blockchain as a core technology has witnessed a myriad of frameworks ingrained with diverse cryptographic primitives as well as non-cryptographic mechanisms. Existing works, however, still suffer from privacy-related challenges chief being privacy breaches based on blockchain digital footprints from health facilities, doctors, and patients alike as well as feasibility challenges. Empirical research from state-of-the-art demonstrates the possibility to deanonymize entities involved in a blockchain transaction via inference analysis using such digital footprints on-chain. In this paper, we address such lacunae by advancing a privacy-conscious feasible blockchain-agnostic EHR sharing framework leveraging anonymous transactions, a smart contract, and decentralized storage technology. We construct a constant-size identity-based ring signature to provide accentuated privacy for transaction initiators and demonstrate how health facilities can anonymously retrieve anonymous data on-chain to facilitate EHR sharing via a novel, robust yet computationally efficient, and privacy-aware algorithm dubbed PatientFinder. We subsequently show proof of concept of our framework. A thorough system evaluation is performed revealing that the solution satisfies the privacy of patients and health facilities (doctors), feasibility, and security-related requirements.

Wildcarded identity-based ring signatures based on linearly homomorphic signatures

In identity-based ring signatures (IBRS) (Zhang and Kim, 2002), a binary string ID∈{0,1}L for L∈N, representing a unique information about a signer (e.g., e-mail address, telephone number), is associated with a secret-key. Its owner can anonymously signs a message under a set of IDs called ring including the signer’s ID. Wildcarded IBRS (WIBRS) (Ishizaka&Kiyomoto, ISC’20) is a generalization of IBRS, in which the ring consists of wildcarded IDs. The signer correctly signs iff her ID matches at least one of the wildcarded IDs. To the best of our knowledge, the only one known WIBRS scheme adaptively secure under standard assumptions is obtained as an instantiation of the attribute-based signatures scheme by Sakai et al. (PKC’16). It has signatures of length O(kL) and secret-keys of (constant) length O(1), where k denotes cardinality of the ring. In this paper, we propose a generic WIBRS construction, built by linearly homomorphic signatures and non-interactive witness-indistinguishable proof. We instantiate it to obtain a concrete WIBRS scheme secure under standard assumptions, whose length of signatures (resp. secret-keys) O(k+L) (resp. O(L)).

Cost-effective anonymous data sharing with forward security using improved authentication

Cloud computing gives customers instant access to a network of remote servers, networks, and data centres. Cloud computing makes data analysis helpful to society and individuals. Sharing data with many people causes efficiency, integrity, and privacy issues. Ring signatures may enable secure and anonymous data transfer. It anonymizes data verification for cloud-based analytics. Identity-based (ID) ring signatures are becoming popular alternatives to public key infrastructure (PKI)-based public-key encryption. PKI bottlenecks are certificate verification time and cost. ID-based ring signatures speed up certificate verification. We observed that encrypting ID-based ring signatures with a variation of SHA-384 and adding forward security considerably improves their security. Padding divides the input text into 512-byte blocks and adds the length as a 48-bit value to the hash in newer SHA versions. Signatures made before a user's secret key was compromised are legitimate. If a user's secret key is compromised, it's impossible to compel all data owners to re-verify their data, hence a large-scale data sharing system must contain this feature. We implement, secure, and prove our method's use. SHA-384 is safer for cloud-based anonymous data sharing.

ID-Based Ring Signature against Continual Side Channel Attack

The security of the signature scheme is destroyed because its secret information of the signature system is leaked due to the side channel attack. Ring signature has good application value, which can provide more flexibility and complete anonymity. It can be used in some systems such as anonymous authentication in ad hoc networks, electronic voting and crypto coin based on blockchain. Because of the side channel attack, the private key of the ring signature system may be exposed, which may cause insecurity. We present a ring signature system against continuous side channel attack. Because of the symmetry of the ring, the user’s identity has good privacy protection. The proposed scheme is completely secure without a random oracle model and the private key disclosure rate is close to 1/3. Through the dual system technique, the existential unforgeability and unconditional anonymity of the scheme are proved in the composite order group based on the subgroup decision assumption.

Identity-based ring signature scheme with multi-designated verifiers

Identity-based ring signature scheme with multi-designated verifiers

Identity-based ring signature scheme with multi-designated verifiers

As far as we know, there is only one ring signature scheme with multi-designated verifiers in the literature and the scheme is based on the bilinear pairings which need to consume a lot of computation and under the traditional public key infrastructure (PKI). In order to improve computational efficiency and solve the problem of certificate management in PKI, in this paper, we propose the first identity-based ring signature scheme with multi-designated verifiers without pairings. We prove that our novel scheme's unforgeability, anonymity in the random oracle model and indistinguishability in the standard model under the intractability assumption of discrete logarithm problem and decisional Diffie-Hellman problem, and we prove that our novel scheme's non-transferability in the standard model. We compare the new scheme with a previous scheme in terms of computation and communication at last. The results show that our new scheme is more efficient than the previous scheme and is more suitable for the multi-user setting.

Efficient identity-based ring identification scheme and identity-based ring signature scheme on lattices

Efficient identity-based ring identification scheme and identity-based ring signature scheme on lattices

O³HSC: Outsourced Online/Offline Hybrid Signcryption for Wireless Body Area Networks

Wireless body area networks (WBAN) enable ubiquitous monitoring of patients, which can change the future of healthcare services overwhelmingly. As the collected data of patients usually contain sensitive information, how to collect, transfer, store and share data securely and properly has become a concerning issue. Attribute-based encryption (ABE) can achieve data confidentiality and fine-grained access control simultaneously. Identity-based ring signature (IBRS) allows patients to prove their identity without leaking any extra (private) information. However, the heavy computational burden of ABE and IBRS is intolerable for most power-limited mobile devices, which account for a large proportion of WBAN devices. This paper combines the attribute-based online/offline encryption (ABOOE) and IBRS to achieve an outsourced online/offline hybrid signcryption ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$O^{3}$ </tex-math></inline-formula> HSC) scheme. As far as we know, this scheme is the first signcryption scheme that adopts IBRS and satisfies online/offline signcryption simultaneously. <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$O^{3}$ </tex-math></inline-formula> HSC divides the key generation and signcryption into offline and online phases to increase the throughput of the central authority and save the power resources of mobile devices, respectively. Besides, outsourced decryption and public signature verification are also realized. <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$O^{3}\mathrm {HSC}$ </tex-math></inline-formula> achieves security under CCA and CMIA, and the performance analysis shows that <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$O^{3}\mathrm {HSC}$ </tex-math></inline-formula> is a lightweight and applicable scheme for WBAN.

Fuzzy Identity-Based Ring Signature from Lattices

In this paper, a construction of a fuzzy identity-based ring signature scheme (LFIBRS) is proposed. Our LFIBRS combines the characteristics of both the fuzzy identity-based signature (FIBS) and the ring signature. On the one hand, a signature issued under an identity ID can be verified by any identity ID ′ that is “close enough” to the identity ID . Since biometric identification is the well-known most popular and reliable identification method, our LFIBRS can be applied in such a situation whenever it is required for official audit or supervision that the signer’s real identity is needed to be authenticated. On the other hand, LFIBRS provides anonymity under the random oracle model. In addition, LFIBRS provides unforgeability under the small integer solution (SIS) lattice hardness assumption which can resist large-scale quantum computer attacks in the future.

Economic authentic and anonymous data sharing with forward security

With the advancements of cloud services, sharing of information has never ever been easier, and intelligent prediction of shared information provides a slew of advantages also to individuals and society. When sharing data with a huge group of people, several factors must be considered, which include effectiveness, authentication, and the confidentiality of the cloud provider. A viable target for constructing an unidentified and genuine interoperability system is ring signature. It enables an owner to privately configure the data that can then be stored or analyzed in the cloud. However, in a conventional Public-Key-Infrastructure (PKI) setting, the expensive credential authentication becomes a limiting factor for this solution's scalability. Instead, an Identity based Ring Signature can be used, which eliminates the need for document verification. We enhance the safety of identity based ring signatures in this paper by adding forward protection: If a user's secret key is corrupted, all previously stored confirmations containing this user are still valid. The whole product is extremely crucial in any big information sharing system, because it is pointless to force all digital assets to conceptual metaphor their data if a single user's secret key is compromised. We demonstrate the practicality of our scheme by providing a tangible as well as efficient implementation and proving its security in good manner.

Efficient identity based ring signature scheme in prime order group

Aiming at the problem of long signature generation and verification time caused by low operation efficiency in ring signature algorithm based on composite order group, an asymmetric identity based ring signature scheme based on prime order group is proposed. The model definition and specific identity based ring signature scheme design of the proposed scheme are described, and the correctness and security of the proposed scheme are analyzed. Finally, the efficiency of the core operation part of the algorithm is explained. Compared with the correlation signature algorithm based on composite order group, the optimization has a great improvement in operation overhead and performance, and the designed scheme is unforgeable. The designed signature scheme meets the unconditional anonymity and unforgeability of ring signature.

Lattice-based identity-based ring signature without trapdoors

So far, most ring signature schemes rely on hard number theory problems, such as discrete logarithm, bilinear pairings and so on. Unfortunately, the above underlying number theory problems will be solvable in the post quantum era. Lattice-based cryptography is a hotspot of research recently, due to its implementation simplicity and provable security reductions. When the hash-and-sign signature scheme was constructed based on the hardness of worst-case lattice problems, provably secure lattice-based ring signature schemes were finally constructed. However, the hash-and-sign ring signatures were rather inefficient (with megabytes long signatures). In this paper, we propose an alternative method for constructing lattice-based and identity-based ring signature scheme which does not use the hash-and-sign methodology. In the random oracle model, the proposed signature scheme based on the problem in general lattices is unforgeable and holds anonymity. Compared with the previous instantiations of the hash-and-sign ring signature schemes, the lengths of secret key, public key and signatures in the proposed scheme are much shorter. The signing algorithm is quite simple, with matrix-vector multiplications and rejection samplings.

Identity-Based Ring Signature for Data Sharing in Cloud with Forward Security

Identity-Based Ring Signature for Data Sharing in Cloud with Forward Security

Public integrity auditing for shared dynamic cloud data

Cloud computing is an important storage platform being researched nowadays. It provides various services to its users. Among them, one of the salient service offered is cloud storage which makes data outsourcing a rising trend. But the major concern associated is the integrity and seclusion of outsourced data. Users require their data to be secure from any modification or unauthorized access. Therefore someway to verify whether the data is intact or not, without retrieving, should exist. This boosts the need of secure remote data auditing. This paper proposes an auditing scheme based on vector commitment, identity based ring signature and group key agreement protocol, emanated on bilinear pairing. An experimental analysis of the proposed scheme, later in the end, shows that when compared with its pertinent schemes, the proposed scheme is also efficient.

A novel identity-based anonymous authentication scheme from multilinear maps

Anonymous authentication is very useful to protect the user's privacy, and plays an important role in building e-commence where involves many partners, such as in cloud computing. With the anonymous property, ring signature provides a cryptographic tool to construct a secure authentication scheme. In this paper, we construct an identity-based ring signature (IBRS) based on Garg-Gentry-Halevi (GGH) graded encoding system which is a candidate multilinear maps from ideal lattice, and prove its security in random oracle model. Under the GGH graded decisional Diffie-Hellman (GDDH) assumption, the proposed ring signature guarantees the anonymity of signer against full keys exposure attacks. Considering unforgeability, under the GGH graded computational Diffie- Hellman (GCDH) assumption, the new scheme provides unforgeability both against selectively chosen subring attacks and insider corruption.

A novel identity-based anonymous authentication scheme from multilinear maps

Anonymous authentication is very useful to protect the user's privacy, and plays an important role in building e-commence where involves many partners, such as in cloud computing. With the anonymous property, ring signature provides a cryptographic tool to construct a secure authentication scheme. In this paper, we construct an identity-based ring signature (IBRS) based on Garg-Gentry-Halevi (GGH) graded encoding system which is a candidate multilinear maps from ideal lattice, and prove its security in random oracle model. Under the GGH graded decisional Diffie-Hellman (GDDH) assumption, the proposed ring signature guarantees the anonymity of signer against full keys exposure attacks. Considering unforgeability, under the GGH graded computational Diffie- Hellman (GCDH) assumption, the new scheme provides unforgeability both against selectively chosen subring attacks and insider corruption.

Lattice-based identity-based ring signature without trapdoors

Lattice-based identity-based ring signature without trapdoors

Enhanced ID-Based Ring Signature by Validating Time Slots in Cloud Environment

Sharing of Information has a number of problems, comprising integrity, information efficiency and safekeeping of data owner in cloud computing. Ring Signature methods are favorable choice to build an unidentified and authentic information sharing system. Ring have no managers, no setup systems, no denial systems, and no coordination: some person can pick any set of members that take account of himself, and sign message by making use of his secret key and the others' public keys, without getting their approval. By using Ring signatures we can leak top-secret information in an anonymous way. In the proposed Id-based ring signature the certificate validation process has been removed which is more cost effective. In this project we improved security in ring by implementing time slots i.e. if a super key of any user has lost then there is no need to change all the users’ keys including the lost key user. Security re-confirmation is avoided in ring Signature by using SHA Algorithm .We have also expanded the level of security in diminished time, easy and effective manner.

Optimal Data Sharing with Forward Security

Cloud Computing is one of the best platform which provides huge data storage and data sharing all over the time and also easily available to the users. Data sharing in the cloud contains the several issues such as data integrity, authenticity, anonymity and privacy of data owner. Identity based (IDbased) ring signature gives anonymous and authentic data sharing system, by using this there is no need of costly certificate verification in the traditional public key infrastructure (PKI).This work, enhances the security of IDbased ring signature with forward security. Using forward security, if private key of the signer is compromised then all the previously generated signatures of that signer remains valid.Using forward security, one of the user may revoke access of file to the other members of the group.

Review on Forward Secure Identity based Ring Signature for Data Sharing in the Cloud

The key feature of cloud computing is one can access information any place, anywhere, at any time. So basically cloud computing is subscription based service where one can obtain network storage space and computer resources for data storage as well as data sharing. Due to high fame of cloud for data storage and sharing, large number of participants gets attracted to it but it leads to issue related to efficiency, Data integrity, privacy and authentication. To overcome these issues, concept of ring signature has been introduced for data sharing amongst large number of users. Ring signatures are used to provide user’s anonymity and signer’s privacy. Use of ID-based ring signature, removes the need of certificate verification which was done using public key infrastructure, hence reduce cost as well as introduction of forward security, further strengthen this system more. Use of weil pairing, keeps even shorter keys secure and it also requires less processing power. So the motivation of this paper is to propose a secure data reading and sharing scheme using above mentioned scheme.