Follow blockchain research across journals, conferences, and preprint repositories.
535 results · page 11 of 23
Bernhard Garn, Klaus Kieseberg, Ceren Çulha, Marlene Koelbing · 5 authors
No abstract is available for this record.
Milan Fičura
No abstract is available for this record.
Mohammed Mujeer Ulla, Deepak S. Sakkari
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.
Thierry Sans, Ziming Liu, Kevin Oh
No abstract is available for this record.
Miaomiao Wang, Lanlan Rui, Siya Xu, Zhipeng Gao · 6 authors
No abstract is available for this record.
Thibauld Feneuil, Matthieu Rivain
No abstract is available for this record.
Suthee Ruangwises
No abstract is available for this record.
Jakub Wyczik
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.
V. Garayeva
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.
Ramveer Singh, Pooja, Ambuj Kumar Agarwal, Rohaila Naaz · 6 authors
In Today's World, Blockchain is a promising Technology in all areas; things have also been drastically changed after COVID-19; challenges surfaced for implementing blockchain technology in the context of its computational complexity and security. After invention of it in 2008, cryptocurrency applications, i.e., Bitcoin it also getting introduced in Different applications. One of the Major Building blocks of Blockchain is Cryptography techniques. This paper discusses Cryptographic primitives used in different phases of Blockchain implementation and the challenges of implementing these cryptographic primitives. Bitcoin uses Cryptographic primitives to generate public-private key pairs and mining, while Ethereum uses Elliptic curve cryptography to create public-private keys and digital signatures. This paper divided uses of cryptographic primitives into three categories used in Blockchains, i.e., key generation Hashes, signature generation hashes, and proof hashes.
Bismark Tei Asare
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.
Chinnam Shanmukha Sai, Narayanan Subramanian
Interplanetary File System (IPFS) is a widely used distributed file system on a peer to peer network to store, share data and handle content management. There is often lack of availability, security and concealment on IPFS, resulting in compromise of confidential information during covert communication. The data in IPFS could be dropped and nodes compressed which results in unavailability of data. IPFS does not encrypt files and users who uploaded the sensitive data can be traced. To overcome these issues a Filecoin-Slate Blockchain (FSB) is adopted in this work. FSB is built on top of content addresser IPFS, a persistent storage ensuring data availability and transaction cost free for users who are uploading data into the FSB. This work proposes a robust and efficient implementation of FSB integrating plain text cryptography and Least Significant Bit (LSB) image steganography. Cryptography along with steganography ensures a strong two-tiered data protection, and adapting FSB guarantees file availability and integrity using inverse embedding technique. The proposed work is tested with nine high quality images and the results validate to maintain confidentiality, availability and integrity of data, for covert communication over FSB.
Mahdi Movahedian Moghaddam, Hossein Albakri, Kourosh Parand
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.
Joceli Mayer
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.
Qingliang Liu, Shuguo Yang, Jing Liu, Li Zhao · 6 authors
No abstract is available for this record.
Clémence Bouvier, Anne Canteaut, Léo Perrin
No abstract is available for this record.
Gizem Kara, Oğuz Yayla
A number of arithmetization-oriented ciphers emerge for use in advanced cryptographic protocols such as secure multi-party computation (MPC), fully homomorphic en-cryption (FHE) and zero-knowledge proofs (ZK) in recent years. The standard block ciphers like AES and the hash functions SHA2/SHA3 are proved to be efficient in software and hardware but not optimal to use in this field, for this reason, new kind of cryptographic primitives were proposed recently. However, unlike traditional ones, there is no standard approach to design and analyze such block ciphers and the hash functions, therefore their security analysis needs to be done carefully. In 2018, StarkWare launched a public STARK-Friendly Hash (SFH) Challenge to select an efficient and secure hash function to be used within ZK-STARKs, transparent and post-quantum secure proof systems. The block cipher JARVIS is one of the first ciphers designed for STARK applications but, shortly after its publication, the cipher has been shown vulnerable to Gröbner basis attack. This paper aims to describe a Gröbner basis attack on new block ciphers, MiMC, GMiMCerfand the variants of JARVIS. We present the complexity of Gröbner basis attack on JARVIS-like ciphers. Then we give results from our experiments for the attack on reduced-round MiMC and a structure we found in the Gröbner basis attack for GMiMCerf•
Alsehli Abrar, Wadood Abdul, Saleh Almowuena, Sanaa Ghouzali · 5 authors
In recent years the use of images in communication has significantly increased. It is important to secure images from unauthorized access and manipulation. Copyright protection approaches protect data from attacks that result in modification, illegal copying or removal. Our proposed approach uses watermarking and blockchain to confirm authentication. Watermarking is a data-hiding technique whereby data is hidden inside an image to make it difficult to modify. Blockchain at its core, is a distributed-ledger that stores secured and encrypted information while ensuring that it is not changed by someone. We present an imperceptible and secure watermarking approach for digital images using the discrete wavelet transform (DWT). The encrypted watermark is saved in the blockchain. When an image is received and it is to be authenticated, the watermark is retrieved from the blockchain and compared with the watermark that is extracted from the given image. The visual quality of the proposed watermarking approach is tested by comparing the original and watermarked images using peak signal-to-noise ratio (PSNR). The basic challenge that we face is finding suitable locations for inserting the watermark while satisfying the imperceptibility aspects along with the security of the algorithm to reach its highest effectiveness.
Xin Liu, Yang Xu, Gang Xu, Xiu‐Bo Chen
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.
Huancheng Lin, Zhehan Wang, Tong Xu, Shanyue Zhou · 6 authors
Recently passwordless authentication such as zero-key authentication or zero-knowledge access control is becoming popular among businesses prioritizing their users' and employees' security and digital experience. A challenge-response mechanism and public key infrastructure (PKI) cryptography are employed to perform the zero-key authentication or zero- knowledge access control that authorizes user access to an online service without a password or any shared secret required. Using a large quantum computer, a quantum algorithm could break the hard mathematical problems underlying PKI. The National Institute of Standards and Technology (NIST) has launched a program and competition to standardize one or more post-quantum cryptographic (PQC) algorithms to fight against quantum attacks. In this paper, we have conducted the first-ever mathematical analysis of lattice-based and polynomial-based PQC by introducing the relationship between automorphism and homomorphism. This analysis can help enterprises and organizations leverage NIST-selected PQC algorithms to safeguard their online services from quantum attacks. We performed the simulation to illustrate brute force broken probability for polynomial-based or multivariate-based PQC to validate our mathematical analysis of PQC.
Komil Tashev, Jamila Arzieva, Ali Arziev, Kuvonchbek Rakhimberdiev
In this article, the issue of authentication of objects of information and communication systems based on mutual authentication, models of authentication of users of information and communication systems, the use a five-level authentication model in the control of access to computer systems, the use of blockchain technology in solving the problem of identification and authentication basics, working principle of Blockstack and uPort authentication protocols based on Blockchain technology, advantages and disadvantages of Blockstack, uPort authentication protocols are analyzed. Also, the working principle of the DNS server system based on the Blockstack authentication protocol, developed on the basis of the Bitcoin blockchain, was studied. The blockchain layer of the Blockstack infrastructure is an analogue of the bitcoin blockchain. Here, the blockchain analogue is crypto-resistant, decentralized, and information is distributed through a consensus mechanism. In the given thesis questions of the authentication of objects of information-communication systems on the basis of mutual authenticate are considered.
Jieheng Zheng, Lin Zhang, Yan Feng, Zhiqiang Wu
Internet of Things (IoT) systems have the great advantage of connecting massive low energy-consumption devices for the information delivery via wireless channels. However, IoT devices suffer from malicious attacks or eavesdropping due to the broadcasting property of wireless channels. With the aim of enhancing the security performances, we first propose a chaotic scrambler, which utilizes the natural high security property of chaotic sequences being aperiodic and sensitive to initial values, to improve the security of signal transmissions. Then, we propose to utilize the traceable and tamper-proof blockchain to integrate the confidential chaotic key into the chain for user identify management and authentications. Subsequently, theoretical security, reliability and throughput capacities are analyzed, and simulation results are provided to validate the design and the theoretical analysis. Furthermore, we present the practical hardware implementation board for the proposed secure chaotic scrambling following the long range wide area network (LoRaWAN) specifications, which demonstrates that the security performances of IoT devices can be effectively enhanced.
William J. Buchanan
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.