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.

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Secure and Efficient Certificateless Signature and Blind Signature Scheme from Pairings

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.457-458.1262 ◽

2013 ◽

Vol 457-458 ◽

pp. 1262-1265

Author(s):

Min Qin Chen ◽

Qiao Yan Wen ◽

Zheng Ping Jin ◽

Hua Zhang

Keyword(s):

Random Oracle Model ◽

Public Key Cryptography ◽

Random Oracle ◽

Blind Signature ◽

Public Key ◽

Signature Scheme ◽

Signature Schemes ◽

Diffie Hellman ◽

Identity Based ◽

Certificateless Signature

Based an identity-based signature scheme, we givea certificateless signature scheme. And then we propose a certificateless blind signature (CLBS) scheme in this paper. This schemeis more efficient than those of previous schemes by pre-computing the pairing e (P, P)=g. Based on CL-PKC, it eliminates theusing of certificates in the signature scheme with respect to thetraditional public key cryptography (PKC) and solves key escrowproblems in ID-based signature schemes. Meanwhile it retains themerits of BS schemes. The proposed CLBS scheme is existentialunforgeable in the random oracle model under the intractabilityof the q-Strong Diffie-Hellman problem.

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Penerapan skema tanda tangan Schnorr pada pembuatan tanda tangan digital

PYTHAGORAS Jurnal Pendidikan Matematika ◽

10.21831/pg.v12i1.11631 ◽

2017 ◽

Vol 12 (1) ◽

pp. 57

Author(s):

Herdita Fajar Isnaini ◽

Karyati Karyati

Keyword(s):

Digital Signature ◽

Hash Function ◽

Discrete Logarithm ◽

Discrete Logarithm Problem ◽

Public Key ◽

Key Generation ◽

Signature Scheme ◽

Private Key ◽

Message Digest ◽

Schnorr Signature

Tanda tangan digital dapat dijadikan sebagai salah satu cara untuk menjamin keaslian pesan atau informasi yang diterima. Salah satu skema yang dapat digunakan dalam membentuk tanda tangan adalah skema tanda tangan Schnorr. Skema tanda tangan ini berdasarkan pada masalah logaritma diskret. Skema ini memerlukan penggunaan fungsi hash yang akan menghasilkan nilai hash pesan untuk pembuatan tanda tangan, yang menjadi salah satu alasan keamanan dari skema ini. Skema tanda tangan Schnorr terdiri dari tiga proses, yaitu: pembentukan kunci, pembuatan tanda tangan serta verifikasi. Kajian ini akan membahas mengenai skema tanda tangan Schnorr dalam membentuk tanda tangan digital sebagai pengaman keaslian informasi, yang dibahas per prosesnya, meliputi: pembentukan kunci, pembuatan tanda tangan yang disertai perhitungan nilai hash serta verifikasi. Hasil dari kajian ini adalah didapatkan algoritma – algoritma dari skema tanda tangan Schnorr, yaitu algoritma pembentukan kunci publik dan kunci privat, algoritma pembuatan tanda tangan, serta algoritma verifikasi tanda tangan.Kata Kunci: tanda tangan digital, skema tanda tangan Schnorr, nilai hash, kunci publik, kunci privat. Implementation of Schnorr Signature Scheme in The Form of Digital Signature AbstractDigital signature can be used as a way to ensure the authenticity of a received message or information. There is a scheme that can be used to form a signature called Schnorr signature scheme. This signature scheme is based on discrete logarithm problem. This scheme requires the use of hash function that will result to a message digest to form the signature, which is the reason of this scheme’s security. Schnorr signature scheme consists of three processes, namely: the key generation, signature formation, and verification. This study will discuss the Schnorr signature scheme in the form of digital signatures as a safeguard of an information’s authenticity, which is discussed process by process, including: the key generation, signature formation as well as the calculation of message digest and verification. The results of this study obtained algorithms - algorithms of Schnorr signature scheme, which is an algorithm of a public key and a private key generation, an algorithm of the signature formation, and an algorithm of signature verification.Keywords: digital signature, Schnorr signature scheme, message digest, public key, privat key

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A New Multivariate-Based Ring Signature Scheme

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.347-350.2688 ◽

2013 ◽

Vol 347-350 ◽

pp. 2688-2692 ◽

Cited By ~ 1

Author(s):

Ling Ling Wang

Keyword(s):

Discrete Logarithm ◽

Public Key ◽

Quantum Computers ◽

Public Key Cryptosystem ◽

Signature Scheme ◽

Signature Schemes ◽

Ring Signature

Most of the existing ring signature schemes are based on traditional cryptography, such as RSA and discrete logarithm. Unfortunately these schemes would be broken if quantum computers emerge. The MQ-problem based Public-Key Cryptosystem (MPKC) is an important alternative to traditional PKCs for its potential to resist future attacks of quantum computers. In this paper, we proposed a new ring signature scheme based on MPKC, which has the properties of consistent, unforgery, signer-anonymity.

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Identity-based threshold ring signature scheme with constant signature size

Journal of Computer Applications ◽

10.3724/sp.j.1087.2012.01385 ◽

2013 ◽

Vol 32 (5) ◽

pp. 1385-1387 ◽

Cited By ~ 1

Author(s):

Hua SUN ◽

Lei GUO ◽

Xue-feng ZHENG ◽

Ai-min WANG

Keyword(s):

Signature Scheme ◽

Ring Signature ◽

Identity Based

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A Pairing-Free Identity-Based Identification Scheme with Tight Security Using Modified-Schnorr Signatures

Symmetry ◽

10.3390/sym13081330 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1330

Author(s):

Jason Chia ◽

Ji-Jian Chin ◽

Sook-Chin Yip

Keyword(s):

Key Management ◽

Discrete Logarithm ◽

Probability Bounds ◽

Diffie Hellman ◽

Identity Based ◽

Symmetric Key ◽

Security Guarantees ◽

Lightweight Authentication ◽

Tight Security ◽

Schnorr Signatures

The security of cryptographic schemes is proven secure by reducing an attacker which breaks the scheme to an algorithm that could be used to solve the underlying hard assumption (e.g., Discrete Logarithm, Decisional Diffie–Hellman). The reduction is considered tight if it results in approximately similar probability bounds to that of solving the underlying hard assumption. Tight security is desirable as it improves security guarantees and allows the use of shorter parameters without the risk of compromising security. In this work, we propose an identity-based identification (IBI) scheme with tight security based on a variant of the Schnorr signature scheme known as TNC signatures. The proposed IBI scheme enjoys shorter parameters and key sizes as compared to existing IBI schemes without increasing the number of operations required for its identification protocol. Our scheme is suitable to be used for lightweight authentication in resource-constrained Wireless Sensor Networks (WSNs) as it utilizes the lowest amount of bandwidth when compared to other state-of-the-art symmetric key lightweight authentication schemes. Although it is costlier than its symmetric key counterparts in terms of operational costs due to its asymmetric key nature, it enjoys other benefits such as decentralized authentication and scalable key management. As a proof of concept to substantiate our claims, we perform an implementation of our scheme to demonstrate its speed and memory usage when it runs on both high and low-end devices.

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Improved cryptanalysis of a ElGamal Cryptosystem Based on Matrices Over Group Rings

Journal of Mathematical Cryptology ◽

10.1515/jmc-2019-0054 ◽

2020 ◽

Vol 15 (1) ◽

pp. 266-279

Author(s):

Atul Pandey ◽

Indivar Gupta ◽

Dhiraj Kumar Singh

Keyword(s):

Discrete Logarithm ◽

Public Key Cryptography ◽

Public Key ◽

Quantum Computers ◽

Group Rings ◽

Diffie Hellman ◽

Algebra Approach ◽

Elgamal Cryptosystem ◽

Diffie Hellman Key Exchange ◽

Equivalent Keys

AbstractElGamal cryptosystem has emerged as one of the most important construction in Public Key Cryptography (PKC) since Diffie-Hellman key exchange protocol was proposed. However, public key schemes which are based on number theoretic problems such as discrete logarithm problem (DLP) are at risk because of the evolution of quantum computers. As a result, other non-number theoretic alternatives are a dire need of entire cryptographic community.In 2016, Saba Inam and Rashid Ali proposed a ElGamal-like cryptosystem based on matrices over group rings in ‘Neural Computing & Applications’. Using linear algebra approach, Jia et al. provided a cryptanalysis for the cryptosystem in 2019 and claimed that their attack could recover all the equivalent keys. However, this is not the case and we have improved their cryptanalysis approach and derived all equivalent key pairs that can be used to totally break the ElGamal-like cryptosystem proposed by Saba and Rashid. Using the decomposition of matrices over group rings to larger size matrices over rings, we have made the cryptanalysing algorithm more practical and efficient. We have also proved that the ElGamal cryptosystem proposed by Saba and Rashid does not achieve the security of IND-CPA and IND-CCA.

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Time-constrained strong multi-designated verifier signature suitable for Internet of things–based collaborative fog computing systems

International Journal of Distributed Sensor Networks ◽

10.1177/15501477211001760 ◽

2021 ◽

Vol 17 (3) ◽

pp. 155014772110017

Author(s):

Han-Yu Lin

Keyword(s):

Internet Of Things ◽

Fog Computing ◽

Discrete Logarithm ◽

Signature Scheme ◽

Computing Systems ◽

Extended Technique ◽

Diffie Hellman ◽

Designated Verifier ◽

Designated Verifier Signature ◽

Cloud Servers

Fog computing is viewed as an extended technique of cloud computing. In Internet of things–based collaborative fog computing systems, a fog node aggregating lots of data from Internet of things devices has to transmit the information to distributed cloud servers that will collaboratively verify it based on some predefined auditing policy. However, compromised fog nodes controlled by an adversary might inject bogus data to cheat or confuse remote servers. It also causes the waste of communication and computation resources. To further control the lifetime of signing capability for fog nodes, an appropriate mechanism is crucial. In this article, the author proposes a time-constrained strong multi-designated verifier signature scheme to meet the above requirement. In particular, a conventional non-delegatable strong multi-designated verifier signature scheme with low computation is first given. Based on its constructions, we show how to transform it into a time-constrained variant. The unforgeability of the proposed schemes is formally proved based on the famous elliptic curve discrete logarithm assumption. The security requirement of strong signer ambiguity for our substantial constructions is also analyzed by utilizing the intractable assumption of decisional Diffie–Hellman. Moreover, some comparisons in terms of the signature size and computational costs for involved entities among related mechanisms are made.

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