Blockchain Papers

Lydia Ouaili

No abstract is available for this record.

Nishanth Uchil

Demand for blockchain ecosystems has seen exponential growth in recent times due to its decentralized nature and trustless verification process for the transactions involved. However, transaction data needs to be leveraged for verification, which coupled with the transparent nature of the blockchain ledger, provides sufficient data for malicious entities to reveal identities and even financial history of users. Data masking techniques have been employed over the years to make blockchain transactions anonymous, making them resistant to identity analysis, a key set of methods being zero-knowledge proof (zk-proof) protocols that guarantee zero data leak. In this research, we develop SpartanDark, a fork of SpartanGold that integrates a zk-proof protocol, Zero-Knowledge Succinct Non-interactive Argument of Knowledge (zk-SNARK) for transaction verification. SpartanDark provides a Decentralized Anonymous Payment scheme (DAP) with anonymity guarantees, akin to the privacy transaction model in Zerocash. Our analysis shows that this transaction model presents a high degree of data privacy when compared to traditional blockchain models, carrying zero identifying information about the transaction across the blockchain, making it implausible for other entities to profile any user and thus reestablishing one of the core tenets of blockchain: privacy.

Zeming Wei, Junlang Zhang, Shansi Ma, Yu Zhou · 9 authors

No abstract is available for this record.

Johanna Maria Kirss, Peeter Laud, Nikita Snetkov, Jelizaveta Vakarjuk

No abstract is available for this record.

Habeeb Syed, Arinjita Paul, Meena Singh, M A Rajan

No abstract is available for this record.

Ощипок Олена-Іванна Василівна

Метою роботи є оптимізувати множення точок еліптичної кривої на скаляр за допомогою модернізованого метода “Подвійне скалярне множення з використанням трюку Штрауса-Шаміра з урахуванням Skew representation” та багато інших підходів. Ще однією метою роботи - зробити використання множення точок еліптичної кривої на скаляр безпечним в межах протоколу Zero-knowledge proof. З'ясувати, який метод множення буде найдешевшим в контексті визначеної метрики. Об’єктом дослідження є множення точок еліптичної кривої на скаляр в системі гаджет бібліотеках рекурсивних zk-Snark’s. Множення повинно виконуватися до стандартів протоколу Zero-knowledge proof. Також розглянуто варіанти практичного застосування описаних методів. У роботі виконане теоретичне та практичне дослідження, огляд алгоритмів та методів розв’язання задачі оптимізації з використанням різноманітних хитростей та підходів. Кодова база була написана мовою програмування Rust в бібліотеці franklin-crypto. Арифметизація, яка застосовується в бібліотеці – Plonkish та lookup table. Крива, яка була використана для тестування множення – Bn256. Ключові слова : точки еліптичної кривої, Zero-knowledge proof, мовою програмування Rust.

Lin You, Chunjie Guo, Gengran Hu

No abstract is available for this record.

David Pointcheval

Electronic voting is one of the most interesting application of modern cryptography, as it involves many innovative tools (such as homomorphic public-key encryption, non-interactive zero-knowledge proofs, and distributed cryptography) to guarantee several a priori contradictory security properties: the integrity of the tally and the privacy of the individual votes. While many efficient solutions exist for honest-but-curious voters, that follow the official procedure but try to learn more than just the public result, preventing attacks from malicious voters is much more complex: when voters may have incentive to send biased ballots, the privacy of the ballots is much harder to satisfy, whereas this is the crucial security property for electronic voting. We present a new technique to prove that an ElGamal ciphertext contains a message from a specific subset (quasi-adaptive NIZK of subset membership), using linearly-homomorphic signatures. The proofs are both quite efficient to generate, allowing the use of low-power devices to vote, and randomizable, which is important for the strong receipt-freeness property. They are well-suited to prevent vote-selling and replay attacks, which are the main threats against the privacy in electronic voting, with security proofs in the generic group model and the random oracle model.

Ginevra Giordani, Lorenzo Grassi, Silvia Onofri, Marco Pedicini

No abstract is available for this record.

JSC “KVANT-TELECOM”, Igor V. Martynenkov

The methods of eliminating vulnerabilities of zero-knowledge succinct non-interactive arguments of knowlede are considered. The methods are based on the security of public parameters formation in the form of common reference strings using a trusted third party and multilateral interaction. The multilateral formation of the common reference strings uses the only honest party with a fixed and unlimited set of participants, as well as verification of the reliability of the results. Examples of increasing the level of security of zero-knowledge succinct non-interactive arguments of knowledge based on the correction of proof verification equations and the values of the common reference strings, eliminating redundant elements from the common reference strings and the keys of proof formation are given. The protocols that develop the construction of the common reference strings from static to updatable and universal versions are mentioned.

JSC «KVANT-TELECOM», I. V. Martynenkov

We consider ways to improve the performance of zero-knowledge succinct noninteractive argument of knowledge (zk-SNARK) based on polynomial sets, such as quadratic arithmetic programs (QAP), square arithmetic programs (SAP), quadratic span programs (QSP), square span programs (SSP), quadratic polynomial programs (QPP), etc. To improve the performance of zk-SNARK, batch data processing methods, various modifications of exponentiation problems, bilinear pairings based on elliptic curves, etc. are used. A comparative analysis of the complexity of the common reference strings formation, the construction and verification of the calculations reliability proofs, as well as the sizes of common reference strings and proofs has been carried out.

Qi Yu, Jiarui Zhang, Han Zhang

No abstract is available for this record.

B. Arulmozhi, J.I. Sheeba, S. Pradeep Devaneyan

The proposed research presents a blockchain-based healthcare system that seeks to address the limitations of current data-sharing methods by providing secure and efficient data transfer, enhancing data privacy and security, enabling effective data sharing interoperability, and promoting data-driven healthcare decision-making. A blockchain platform, IPFS, and rule-based access control are among the technologies suggested for use in the proposed system. Implementing this system could result in more personalized and effective medication for patients, as well as lower healthcare costs and improved care quality. The suggested approach, known as the Homomorphic Zero-Knowledge Blockchain Algorithm (HZBA), employs a block chain technique linked with Proxy Re Encryption with Homomorphic with Zero proof knowledge. Finally, the Covid19-dataset has collected from Kaggle repository and HCDNN method has used to complete the classification. The proposed blockchain-based healthcare system has the potential to revolutionize healthcare by resolving data privacy and security concerns, increasing data accuracy, fostering more interoperability in data sharing, and enhancing data-driven healthcare decision-making. The proposed blockchain-based healthcare system provides potential answers to data sharing difficulties in the healthcare business. One potential disadvantage is the system's complexity and cost of installation. The experimental results and classification performance parameters have been thoroughly demonstrated

Nima Sedaghat, Brianna Smart, J. Bryce Kalmbach, Erin L. Howard · 5 authors

We report a study exploring how the use of deep neural networks with astronomical Big Data may help us find and uncover new insights into underlying phenomena: through our experiments towards unsupervised knowledge extraction from astronomical Big Data we serendipitously found that deep convolutional autoencoders tend to reject telluric lines in stellar spectra. With further experiments we found that only when the spectra are in the barycentric frame does the network automatically identify the statistical independence between two components, stellar vs telluric, and rejects the latter. We exploit this finding and turn it into a proof-of-concept method for removal of the telluric lines from stellar spectra in a fully unsupervised fashion: we increase the inter-observation entropy of telluric absorption lines by imposing a random, virtual radial velocity to the observed spectrum. This technique results in a non-standard form of ``whitening'' in the atmospheric components of the spectrum, decorrelating them across multiple observations. We process more than 250,000 spectra from the High Accuracy Radial velocity Planetary Search (HARPS) and with qualitative and quantitative evaluations against a database of known telluric lines, show that most of the telluric lines are successfully rejected. Our approach, `Stellar Karaoke', has zero need for prior knowledge about parameters such as observation time, location, or the distribution of atmospheric molecules and processes each spectrum in milliseconds. We also train and test on Sloan Digital Sky Survey (SDSS) and see a significant performance drop due to the low resolution. We discuss directions for developing tools on top of the introduced method in the future.

Benedikt Bünz, Ben Fisch

No abstract is available for this record.

Yu Cao, Xuehui Du, Xiangyu Wu, Qiantao Yang · 6 authors

No abstract is available for this record.

Pablo Santamaría, Llanos Tobarra, Rafael Vargas, Antonio Robles-Gómez

No abstract is available for this record.

Sungwook Kim, Gwangwoon Lee, Hyeonbum Lee, Jae Hong Seo

An inner product (IP) argument is a proof system that convinces the verifier of an IP relation between committed integer vectors. IP arguments are crucial building blocks for range proof and zero knowledge arguments, which can be applied to verifiable computation, confidential transactions, decentralized identification, and so on. This paper proposes a novel efficient IP argument with a trustless setup. For integer vectors of size N, the proposed IP argument provides a proof size of O(log2 N), a verification cost of O(√N), and a size of public parameter size of O(√N). The construction uses bilinear pairings and its security relies solely on the discrete logarithm (DL) assumption, a well-established standard cryptographic assumption. Consequently, we obtain the first DL-based IP argument with a trustless setup that achieves a sublinear verifier and logarithmic proof size, which we call Leopard. Furthermore, We empirically evaluate the performance of Leopard. The experimental results demonstrate that Leopard is highly efficient and scalable compared to previous works.

Matthijs Van Den Bos, Victor Ermolaev, Scott A. King, Alexey Koren · 5 authors

No abstract is available for this record.

Mathias Hall-Andersen, Jesper Buus Nielsen

No abstract is available for this record.

Heba Elgabri, Mohamed Sameh Hassanein

The purpose of this article is to propose a framework named IoT-AC/Bc to secure smart cities. This article describes a new method that integrates Role-Based Access Control (RBAC) and Zero-Knowledge Proof (ZKP) models based on IoT and blockchain technologies. This method enables fast access authentication on smart city gates using ZKP, which provides an extra layer of security to address access control challenges. The framework consists of an Internet of Things Access Control-based Blockchain Smart Contract that manages user authentication, access session identities, and asset real-time interactions; and a Blockchain Ledger Management Smart Contract that implements distributed access control and tracks the ledger history of different activities. The framework achieves availability, scalability, multi-factor authentication, and decentralization, which strengthens distribution, role authority, access rights, and concurrent identity access requests. The results are demonstrated through a comparative analysis focused on the number of multithreaded requests, the cost of smart contract deployment, the multi-factor authentication performance for users’ interactions with the smart city gates, and the security strength levels. The framework’s performance effectiveness is evaluated through a case study that consists of various scenarios. The framework allows improving the security level by 94% under low and medium attack strength and 89% under high attack strength for 18 security attacks. This paper is novel because the framework uses ZKP over a blockchain network as an extra cryptographic technique with RBAC as a logical access control model to achieve fast accessibility authorization for users’ transactions while preserving their private identity on smart city gates. Keywords: Access Control, Blockchain, Internet of Things, Role-Based Access Control, Smart Cities, Multi-Factor Authentication DOI： https://doi.org/10.35741/issn.0258-2724.58.4.56

Ismail Afia, Riham AlTawy

No abstract is available for this record.

Yuta Maeno, Hideaki Miyaji, Atsuko Miyaji

No abstract is available for this record.

Miguel Ambrona, Marc Beunardeau, A.-L. Schmitt, Raphaël R. Toledo

No abstract is available for this record.