G. Sucharitha, V. Sitharamulu, Sachi Nandan Mohanty, Anjanna Matta · 5 authors
The use of encryption is essential to protect sensitive data, but it often poses challenges when it comes to locating and retrieving information without decryption. Searchable encryption provides an effective mechanism that achieves secure search over encrypted data. In this paper a new approach to address the fine-grained search and to protect sensitive data, Blockchain Assisted ciphertext policy decentralized attribute-based encryption (BA-CP-DABE) in cloud has been developed. The CP-DABE is employed to manage data access, secure key generation, while the immutability of blockchain ensures the confidentiality of ciphertext. By leveraging searchable encryption, it becomes possible to securely search encrypted data stored on the blockchain. Keywords are encrypted using attribute-based encryption and stored on a remote server, along with the corresponding ciphertext in the blockchain. One of the significant challenges in this approach is the assumptions-based technique i.e., bilinear mapping, which involves keyword ciphertext and trapdoor security. However, through extensive numerical experiments, the system has demonstrated its ability to generate key and trapdoor structures, as well as effectively find keywords within the encrypted data.
The article discusses the encryption security of the Bitcoin Core cryptocurrency wallet. Particular attention is paid to aspects of the practical implementation of cryptographic algorithms when encrypting the wallet.dat file with a password. The practical strongness to brute-force attacks using parallel computing on the GPU is also considered. It was found that Bitcoin Core did not implement an encryption key change for private keys. This implementation makes it possible to re-attack the wallet without knowing the new password, if it has already been compromised before. The changes to encryption algorithms that complicate the password brute force attacks on the GPU are also proposed.
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.
Blockchain is a technology that enables decentralized digital currencies like bitcoin, ethereum, and ripple. It is widely used in many areas such as healthcare, defense, and industrial domains like internet of things for tracking sensor data and detecting duplicate sensor data. Bitcoin is one of the most popular cryptocurrencies due to its market value and use as a medium of exchange. The trustless secure money exchanges have made bitcoins appealing to people. However, the loose possession of bitcoin keys can lead to monetary loss and a decrease in bitcoin users. In this article, we provide an extensive analysis of major privacy and security issues in the Bitcoin blockchain. First, we discuss the security issues in bitcoin, and second, we discuss countermeasures for these bitcoin threats. Third, we provide an added level of security using elliptic curve cryptography on bitcoin multi-signature accounts. Our research helps bitcoin users understand the risks involved in using non-multi-signature accounts compared to multi-signature accounts. The use of elliptic curve cryptography on bitcoin multi-signature accounts also helps to avoid unnecessary expenses such as bitcoin currency rewards to miners.
Open access
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
This article addresses the lack of comprehensive studies on Web3 technologies, primarily due to lawyers' reluctance to explore technical intricacies. Understanding the underlying technological foundations is crucial to enhance the credibility of legal opinions. This article aims to illuminate these foundations, debunk myths, and concentrate on determining the legal status of crypto-assets in the context of property rights within the distributed economy. In addition, this article notes that the intangible nature of crypto-assets that derive value from distributed registries, and their resistance to deletion, makes crypto-assets more akin to the autonomy of intellectual property than physical media. The article presents illustrative examples from common law (United States, United Kingdom, New Zealand) and civil law (Germany, Austria, Poland) systems. Proposing a universal solution, it advocates a comprehensive framework safeguarding digital property - data ownership - extending beyond the confines of Web3. This article presents a comprehensive, multi-layered approach to the analysis of tokens as digital content and virtual goods. The approach, universally applicable to various of such goods, scrutinizes property on three distinct layers: first, the rights to the virtual good itself; second, the rights to the assets linked to the virtual good; and third, the rights to the intellectual property intricately associated with the token. Additionally, the paper provides concise analysis of the conflict of laws rules applicable to virtual goods. It also delves into issues concerning formal requirements for the transfer of intellectual property rights, licensing, the first sale (exhaustion) doctrine, the concept of the lawful acquirer, and other crucial aspects of intellectual property in the realm of virtual goods, particularly within the emerging metaverse.
Cryptocurrency is a digital payment system, created by non-banks, not subject to any official license, and is mainly mined using blockchain technology. The process of emission of cryptocurrency is called mining, and since cryptography is used, the meaning of "crypto" is mentioned at the beginning of the word currency. Cryptocurrency transactions do not require personal information. This means that users remain largely anonymous and transactions are largely confidential. However, every transaction is recorded, senders and receivers are known to the public. This way, all transactions are tracked, no transaction can be changed, manipulated or deleted afterwards. In this respect, cryptocurrencies are a bit more transparent than digital currencies. Cryptocurrencies and digital wallets, which are the most popular nowadays, are similar but have different functions. In this regard, the article we present is suitable for economically interested individuals or organizations.
High profile cybersecurity attacks on networks and the occurrences of critical security breaches on existing wireless sensor networks grow by the day. The distributed ledger technology provided for by blockchainwith all its benefits has shown great industrial prospects in the face of the rampant occurrences of cyber thefts of critical data from compromised networks. The centralized identity model relies on centralized authentication mechanisms that create a single point of failure for such database systems. Again, thecentralized data is a honeypot for cyber-attacks.Blockchain as a database structure adopts an authentication mechanism that depends on the distributed ledger technology to eliminate the incidences of single point of failure.Although Blockchain holds security benefits for ensuring enhanced privacy and confidentiality for stored data, the computational overhead in classical blockchain technology makes it a challenge for full use in a network where its devices are resource constrained. In this thesis, solutions have been proposed to solve the aforementioned problems. The main contributions of the PhD thesis are the following: the proposal of a blockchain-based architecture for IoT security, the proposal of cryptographic approaches for securityreinforcement in blockchain-based architectures, and the elaboration of a model based on a formal approach, namely Petri nets, for simulation, analysis and verification of blockchain-based architectures for IoT.
Open access
Advanced Steganography and Watermarking Techniques
Abstract Today, with the growth of cryptocurrencies, the importance of keeping them has increased. Wallets are one of the ways to keep cryptocurrencies safe. One of the techniques for securing cryptocurrency wallets is the use of multi-signature technique. This technique is based on a concept called secret sharing. In order to ensure the security of these wallets, the secret sharing scheme is used, which uses the Lagrange interpolation algorithm. This algorithm has a challenge in terms of time complexity, and in this research, we introduced two parallel approaches to reduce this time complexity based on graphical processor units (GPU) and distributed systems. In addition to reducing the time complexity, the distributed approach was able to help us increase the security of the algorithm. The speedup obtained from the execution on the interpolation of 16384 points in the GPU-based approach was equal to 45214 and in the distributed approach, in the execution resulting from 4 to 128 processes was equal to 7.81.
The recent creation of Non Fungible Tokens (NFTs) has enabled a multibillionaire market for digital artistic works including images or sequence of images, videos, and animated gifs. With this new trend issues regarding fraud, stolen works, authenticity, and copyright came along. The goal of this chapter is to provide an overview of the watermarking techniques that can be employed to mitigate those issues. We will discuss transparency, robustness, and payload of watermarking techniques aiming to educate the artists, researchers, and developers about the many approaches that watermarking techniques provide and the resulting trade-offs. We focus on fragile watermarking techniques due to their high transparency for embedding into artistic works. We discuss the spread spectrum and Least Significant Bit techniques. We describe the usual process of NFT minting into a blockchain and propose a more secure certification protocol with watermarking which employs the same usual NFT minting offered by current marketplaces. The proposed certification protocol mints a checksum string into a blockchain, ensuring the validity of the watermark and the information embedded into this watermark. This proposed protocol validates the date of creation and author identification which are transparently embedded in the artistic work, thus, increasing the security and confidence of markets for artistic works transactions.
Open access
Advanced Steganography and Watermarking Techniques
Abstract With the the advent era of big data, the secure computation calculates data on the premise of protecting data privacy, to realize the availability and invisibility of data. Secure multi-party computation, as one of three major technical tools of privacy computing, can still securely carry out data collaborative computation without a trusted third party. As an important branch of secure multi-party computation, the secure computing geometric problem can solve practical problems in the military, national defense, finance, life, and other fields, which has important research significance. In this paper, the graphic similarity problem is studied. Firstly, this paper proposes the adjacency matrix vector coding method of isomorphic graphics and uses the Paillier variant cryptosystem to securely solve the graphic similarity judgment under the semi-honest model. By using an elliptic curve cryptosystem and zero-knowledge proof to solve the possible malicious attacks under the semi-honest model, a graphic similarity judgment protocol under the malicious model is designed. The protocol can resist malicious attacks, has high computational efficiency, and has wide application value.
Cryptography has proven to be one of the most contentious areas in modern society. For some it protects the rights of individuals to privacy and security, while for others it puts up barriers against the protection of our society. This book aims to develop a deep understanding of cryptography, and provide a way of understanding how privacy, identity provision and integrity can be enhanced with the usage of encryption. The book has many novel features including: • full provision of Web-based material on almost every topic covered • provision of additional on-line material, such as videos, source code, and labs • coverage of emerging areas such as Blockchain, Light-weight Cryptography and Zero-knowledge Proofs (ZKPs) Key areas covered include: • Fundamentals of Encryption • Public Key Encryption • Symmetric Key Encryption • Hashing Methods • Key Exchange Methods • Digital Certificates and Authentication • Tunneling • Crypto Cracking • Light-weight Cryptography • Blockchain • Zero-knowledge Proofs This book provides extensive support through the associated website of: http://asecuritysite.com/encryption
Dexin Zhu, Jun Zheng, Hu Zhou, Jianan Wu · 6 authors
Traditional video conference systems depend largely on computational complexity to ensure system security, but with the development of high-performance computers, the existing encryption system will be seriously threatened. To solve this problem, a hybrid encryption scheme for quantum secure video conferencing combined with blockchain is proposed in this study. In the system solution architecture, first, the quantum key distribution network is embedded in the classic network; then, the “classical + quantum” hybrid encryption scheme is designed according to the secret level required for the video conference content. Besides, the real-time monitoring module of the quantum key distribution network is designed to ensure that users can check the running state of the network at any time. Meeting minutes can be shared by combining with blockchain. In order to quickly query meeting minutes, a cache-efficient query method based on B+ tree is proposed. The experimental results show that compared with the traditional video conference system, the quantum secure video conference system sufficiently integrates the technical advantages of the quantum key distribution to resist the security threats such as channel eavesdropping and high-performance computational attacks while ensuring the stable operation of the classic system, thus providing a video conference system with a higher security level. Meanwhile, the query time cost of blockchain with different lengths is tested, and the query efficiency of the proposed method is 3.15-times higher than the original query efficiency of blockchain.
Open access
Chaos-based Image/Signal Encryption
Cryptography and Data Security
Advanced Steganography and Watermarking Techniques
Yi Chen, Chung-Chiang Chen, Li‐Chuan Tang, Wei-Hua Chieng
Abstract NuText is a novel music-encoding technology based on numbered musical notation. This paper outlines the notation principles of numbered musical notation and delineates the conversion relationship and encoding protocol between NuText and numbered musical notation. Furthermore, this study demonstrates NuText's playback software and its practical applications, including digital artwork creation, Non-Fungible Tokens (NFTs), and social use, and identifies opportunities to develop it as a music technology. The encoding method proposed herein was implemented on PCs and mobile devices, and the method has been successfully applied to sports-oriented music. The image steganography method used in digital artwork creation, Non-Fungible Tokens (NFTs), and social use does not destroy images, and it has been implemented on mobile devices. NuText is a note-level encoding method, which has advantages for interpreting music connotations and a great potential in the development of music information retrieval and artificial intelligence composition. In future work, special musical skills may be added, including the modification of each note velocity, and this may be incorporated into the encoding specification to realize sound in virtual reality.
Open access
Advanced Steganography and Watermarking Techniques
By using zkSNARKs to prove that values have specific dependent types, it is possible to provably assure compatibility and correctness without revealing sensitive information and extend our trusted computing base well beyond our own system. The approach we developed expands the scope of what non-interactive zero-knowledge proofs can capture to include properties about both the execution and correctness of programs.
Probabilistically Checkable Proofs (PCPs) allows a randomized verifier, with oracle access to a purported proof, to probabilistically verify an input statement of the form “x∈L” by querying only a few proof bits. Zero-Knowledge PCPs (ZK-PCPs) enhance standard PCPs to additionally guarantee that the view of any (possibly malicious) verifier querying a bounded number of proof bits can be efficiently simulated up to a small statistical distance. The first ZK-PCP construction of Kilian, Petrank and Tardos (STOC 1997), and following constructions employing similar techniques, necessitate that the honest verifier makes several rounds of queries to the proof. This undesirable property, which is inherent to their technique, translates into increased round complexity in cryptographic applications of ZK-PCPs. We survey two recent ZK-PCP constructions—due to Ishai, Yang and Weiss (TCC 2016-A), and Hazay, Venkitasubramaniam and Weiss (ITC 2021)—in which the honest verifier makes a single round of queries to the proof. Both constructions use entirely different techniques compared to previous ZK-PCP constructions, by showing connections to the seemingly-unrelated notion of leakage resilience. These constructions are incomparable to previous ZK-PCP constructions: while on the one hand the honest verifier only makes a single round of queries to the proof, these ZK-PCPs either obtain a smaller (polynomial) ratio between the query complexity of the honest and malicious verifiers or obtain a weaker ZK guarantee in which the ZK simulator is not necessarily efficient.
We propose N-choice game (NCG), a decentralized pseudo-random number generation method that can be executed on smart contracts. Of the M participants, one is a dealer, and the rest are players, each with a different role. Each participant randomly chooses one value between 0 and N − 1 and receives a score determined by the NCG rule. The amount of reward each participant receives is determined by the score. The values chosen by the participants are combined and hashed into a pseudo-random number. The NCG framework is designed to achieve the following three goals: (1) Incentivize participants to provide random choices, (2) Evaluate the level of randomness in the decentralized environment, and (3) Establish high performance. We implement the NCG framework in Solidity and evaluate its performance. Our extensive experiments revealed that unless more than 90% of NCG players collide, the generated random numbers have high randomness that can pass the NIST randomness test. The experiments also demonstrated that the throughput of random number generation in NCG was 129 times faster than in the existing framework, Random Bit Generator [2].
Open access
Chaos-based Image/Signal Encryption
Advanced Steganography and Watermarking Techniques
The consensus mechanism is the core secret of the blockchain network. However, the consensus mechanism of the classical blockchain is based on the classical cryptosystem, which is based on the problem of computational complexity. With the improvement of computing power, the security of this cryptosystem is being threatened. In addition, the consensus mechanism of classic blockchain also has the following disadvantages: serious waste of computing resources and energy; the inability to withstand a 51% attack; low system throughput and large delay. Based on quantum teleportation technology and the randomness of quantum measurement, a consensus mechanism for a quantum blockchain system is proposed. Based on the physical properties of quantum mechanics, this scheme has the unconditional security of quantum cryptography. This new consensus mechanism does not involve a great deal of computing resources and hence has a lower energy consumption, shorter time delay and higher throughput. Furthermore, the new consensus mechanism could withstand a 51% attack.
Open access
Blockchain Technology Applications and Security
Chaos-based Image/Signal Encryption
Advanced Steganography and Watermarking Techniques