Blockchain Papers

Nicolas Six, Claudia Negri-Ribalta, Nicolas Herbaut, Camille Salinesi

Blockchain has been praised for its capacity to hold data in a decentralized\nand tamper-proof way. It also supports the execution of code through\nblockchain's smart contracts, adding automation of actions to the network with\nhigh trustability. However, as smart contracts are visible by anybody on the\nnetwork, the business data and logic may be at risk, thus companies could be\nreluctant to use such technology. This paper aims to propose a pattern that\nallows the execution of automatable legal contract clauses, where its execution\nstates are stored in an on-chain smart-contract and the logic needed to enforce\nit wraps it off-chain. An engine completes this pattern by running a business\nprocess that corresponds to the legal contract. We then propose a pattern-based\nsolution based on a real-life use case: transportation of refrigerated goods.\nWe argue that this pattern guarantees companies pseudonymity and data\nconfidentiality while ensuring that an audit trail can be reconstituted through\nthe blockchain smart-contract to identify misbehavior or errors. This paper\npaves the way for a future possible implementation of the solution described,\nas well as its evaluation.\n

Mohammed Amine Bouras, Qinghua Lu, Sahraoui Dhelim, Huansheng Ning

Identity management is a fundamental feature of Internet of Things (IoT) ecosystem, particularly for IoT data access control. However, most of the actual works adopt centralized approaches, which could lead to a single point of failure and privacy issues that are tied to the use of a trusted third parties. A consortium blockchain is an emerging technology that provides a neutral and trustable computation and storage platform that is suitable for building identity management solutions for IoT. This paper proposes a lightweight architecture and the associated protocols for consortium blockchain-based identity management to address privacy, security, and scalability issues in a centralized system for IoT. Besides, we implement a proof-of-concept prototype and evaluate our approach. We evaluate our work by measuring the latency and throughput of the transactions while using different query actions and payload sizes, and we compared it to other similar works. The results show that the approach is suitable for business adoption.

Omid Torki, Maede Ashouri-Talouki, Mojtaba Mahdavi

Steganography is a solution for covert communication and blockchain is a p2p network for data transmission, so the benefits of blockchain can be used in steganography. In this paper, we discuss the advantages of blockchain in steganography, which include the ability to embed hidden data without manual change in the original data, as well as the readiness of the blockchain platform for data transmission and storage, which eliminates the need for the Steganographer to design and implement a new platform for data transmission and storage. We have proposed two algorithms for steganography in blockchain, the first one is a high-capacity algorithm for the key and the steganography algorithm exchange and switching, and the second one is a medium-capacity algorithm for embedding hidden data. Also, by reviewing the previous three steganography schemes in blockchain, we have examined their drawback and have showed that none of them are practical schemes for steganography in blockchain. Then, we have explained the challenges of steganography in blockchain from the steganographers and steganalyzers point of view.

S. Devidas, Subba Rao Y.V., N. Rukma Rekha

Group signature schemes play a vital role in protecting identity privacy of a member of a group who signs a message using the group signature. However, in the existing group signature schemes the centralized group manager has control over all the participants, and these managers can be malicious. They may take a biased decision when there is a dispute among the group members or while revealing the identity of a group member. To overcome the trust issues related to centralized group managers and to improve user privacy, a decentralized group signature scheme (DGSS) is proposed by decentralizing the role of the group manager. The proposed scheme will be more suitable for decentralized environments like a blockchain. Security analysis along with the proof of correctness is also provided for the proposed scheme. A framework for a blockchain-based e-auction protocol using the DGSS is also proposed in this paper.

Neha S Aswale

No abstract is available for this record.

Zhaozhong Guo, Liucheng Shi, Maozhi Xu, Yin Hong

Covert channels are designed to protect the communication relationship of the sender and receiver. Traditional covert channels have become insecure due to the continuous improvement of traffic analysis techniques. In this context, there is an urgent need to identify new approaches for covert channels. Blockchain is an emerging technique with characteristics of user anonymity, a flooding propagation mechanism, and tamper resistance, which make it a compelling platform for covert channels. Previous approaches applied Bitcoin as the underlying blockchain, and its pseudoanonymity may expose the communication relationship. Moreover, the reliance of these approaches on prenegotiated labels to identify transactions containing covert messages further reduced their concealment. In this work, we present a practical and secure covert channel over Monero. Compared to Bitcoin, Monero's full anonymity efficiently protects the relationship between the sender and receiver. Moreover, no labels are employed to identify special transactions. The receiver filters and extracts the covert message using his private key. In this study, we make a complete assessment of the robustness, reliability, and anti-traceability of our protocol, as these properties are regarded as desirable for a covert channel. We also formalize the definition of security for covert channels through a transaction distinguishing experiment. A rigorous proof shows that our protocol meets this definition and is secure to use. Finally, we make a detailed comparison between our protocol and the existing blockchain-based covert channels.

Leyou Zhang, Ke Huang, Fatemeh Rezaeibagha, Yi Mu

Bitcoin transactions rely on digital signatures to prove the ownership of bitcoin. The private signing key of the bitcoin owner is the key component to enable a bitcoin transaction. If the signing key of a bitcoin is stolen, the theft who possesses the key can make a transaction of the bitcoin. In this paper, based on the distance-based encryption (DBE), we propose an enhanced version of bitcoin in order to protect the signing key. Our approach is based on our two-factor authentication, where the signing key cannot be retrieved without being identified via the password and biometric authentication scheme, and the user is only required to enter his password and fingerprint (or other biometric information such as a factual image) to retrieve the key. By doing this, we can effectively improve the bitcoin security and provide stronger authentication. An attractive feature of our scheme is that one of encryption schemes is asymmetric, in the sense that the decryption key (biometric information) is not stored in the device. We also provide the security model and proof to justify the security of our scheme.

Wael A. Mahrous, Mahmoud Farouk, Saad M. Darwish

Due to businesses’ growing use of IoT services in their day-to-day operations and the increased use of smart devices, digital forensic investigations involving such systems will need increasingly sophisticated digital evidence collection and processing. The majority of IoT systems are composed of disparate software and hardware components, which may pose security and privacy concerns. Recently, blockchain technology was presented as one of the options for achieving IoT security via the use of an immutable ledger, a decentralized architecture, and strong cryptographic primitives. Integrating blockchain platforms with IoT-based applications, on the other hand, poses a number of difficulties owing to the trustworthiness, integrity, and real-time responsiveness of IoT data. However, certain IoT devices may be incompatible with existing blockchain-based IoT forensic methods for additional digital evidence processing owing to their usage of conventional hash. A critical feature of cryptographic hash functions is that even if just one bit of the input is altered, the output acts pseudo-randomly, making it impossible to identify identical files. However, in the field of computer forensics, it is essential to locate comparable files (e.g., various versions of a file); therefore, we need a hash function that preserves similarity. It is getting more difficult to establish how forensic investigators might utilize traces from such devices. To effectively deal with IoT digital forensics applications, this article presents an improved blockchain-based IoT digital forensics architecture that use fuzzy hash to construct the Blockchain’s Merkle tree in addition to the conventional hash for authentication. Fuzzy hashing enables the identification of potentially damning documents that might otherwise remain undiscovered using conventional hashing techniques. By comparing blocks/files to all nodes in the blockchain network using fuzzy hash similarity, the digital forensics investigator will be able to verify their authenticity. To support the proof of concept, we simulated the suggested model.

B. Sowmiya, E. Poovammal, Kadiyala Ramana, Saurabh Singh · 5 authors

Cloud computing is a continuously evolving technology that can enhance agility, availability, collaboration and scalability of data. Blockchain has a secure, immutable ledger which maintains all the transactions along with the timestamp. The blockchain framework and cloud computing technology jointly provides different ways of computational cost reduction. The existing methods help to identify the anonymous documents which are given in the form of requests from the cloud server. If the anonymized document requests are from the authorized users, then cloud provides better security and hence documents are not available for unauthorized users. But the main issue is access rights available for authorized users on sensitive data of the owner. To maintain the privacy the sensitive data are hidden using cryptographic techniques even for authorized users. The method adopted is Linear Elliptical Curve Digital Signature (LECDS) with Hyperledger blockchain, to prevent private data loss. The Linear regression method is used to classify the user information into two classes namely sensitive and non-sensitive. The non-sensitive data is encrypted using RSA and sensitive data is encrypted using LECC method. Modified Spider optimization search Algorithm (MSOA) is used to verify the integrity of outsourced data and search user query information in a cloud server. The hyper ledger blockchain verifies the user policy to create a private network through which the user communicates the cloud. In the analysis of the proposed method, the results are evaluated using various performance metrics such as security, throughput, classification accuracy and error rate.

Qiang Tang

After its debut with Bitcoin in 2009, Blockchain has attracted enormous attention and been used in many different applications as a trusted black box. Many applications focus on exploiting the Blockchain-native features (e.g. trust from consensus, and smart contracts) while paying less attention to the application-specific requirements. In this paper, we initiate a systematic study on the applications in the education and training sector, where Blockchain is leveraged to combat diploma fraud. We first present a general system structure for digitized diploma management systems and identify both functional and non-functional requirements. We then show that all existing Blockchain-based systems fall short in meeting these requirements. Inspired by the analysis, we propose a Blockchain-facilitated solution by leveraging some basic cryptographic primitives and data structures. Our analysis shows that the proposed solution respects all the identified requirements by design and can be further extended to enhance its security and privacy guarantees. Finally, we investigate the proposed solution’s computational complexity and demonstrate its practicality.

Abdullah Ayub Khan, Mueen Uddin, Aftab Ahmed Shaikh, Asif Ali Laghari · 5 authors

Due to globalization and worldwide connectivity, multimedia data exchange has increased significantly over the Internet in the last decade. The life cycle of multimedia content is also getting more multifaceted as more people are accessing, sharing, modifying and re-using multimedia information. This poses serious challenges for the multimedia industry to provide integrity, reliability and trustworthiness for multimedia investigations against the growing cybersecurity threats. This paper bridges this gap by enabling a secure and transparent digital forensic investigations process using blockchain technology. MF-Ledger a Blockchain Hyperledger sawtooth-enabled novel, secure and efficient digital forensic investigation architecture is proposed where participating stakeholders create a private network to exchange and agree on different investigation activities before being stored on the blockchain ledger. We have created digital contracts (smart contracts) and implemented them using sequence diagrams to handle the stakeholders' secure interaction in the investigation process. The proposed architectural solution delivers robust information integrity, prevention, and preservation mechanism to permanently and immutably store the evidence (chain of custody) in a private permissioned encrypted blockchain ledger.

Gabin Heo, Dana Yang, Inshil Doh, Kijoon Chae

Blockchain is attracting attention as a new solution for problems such as illegal copying, profit distribution, and forgery and falsification in the digital content trading environment, which has become an essential asset in the information age. However, one problem is that it is difficult to propagate digital content to the blockchain network because of a limited capacity to upload to the blockchain. The integrity and transparency of blockchain are also considered as weak points in terms of privacy. In this paper, we propose a new blockchain system, the secret block-based blockchain (SBBC), to address the problems with the blockchain system in the digital content trading environment. SBBC is composed of off-chain and on-chain network components. Off-chain is the part that allows trading digital content through the authentication phase. The digital content that is traded has a digital fingerprint inserted, so if an illegal leak occurs, the destination can be tracked. In addition, the content is encrypted and traded, and only the rightful user can use the digital content, thus ensuring income for the legitimate content author. Next, the on-chain network is licensed to use digital content, and a verification process using a consensus algorithm is performed. The licensed consumer creates a secret block of their transaction and records it only on their ledger. In a private part, secret block creation ensures privacy and solves the network overload that can occur when uploading digital content to the blockchain. Finally, through the verification and agreement of all blockchain participants, a public block is created and recorded in the ledger to finalize the transaction. Consequently, we propose the SBBC system suitable for digital content trading environments and a safe and reliable system through a consensus algorithm in such environments.

Ming Li, Leilei Zeng, Le Zhao, Renlin Yang · 6 authors

With the application of multimedia big data, the problems such as information leakage and data tampering have emerged. The security of images which is one of the most typical multimedia has become a major problem facing the large-scale open network environment. This paper proposed a blockchain-watermarking scheme to protect the privacy, integrity and availability of compressed sensed images, which effectively combines multimedia watermarking, compressed sensing, Interplanetary File System (IPFS) and blockchain technologies. Based on the reliable authentication of watermarking, the confidentiality protection of compressed sensing, the secure storage of IPFS, and the decentralization and non-tamperability of blockchain, the all-round security protection of the image big data based on compressive sensing can be realized. Experiments show that the proposed scheme is effective and feasible.

Alsehli Abrar, Wadood Abdul, Sanaa Ghouzali

Image authentication is an important field that employs many different approaches and has several significant applications. In the proposed approach, we used a combination of two techniques to achieve authentication. Image watermarking is one of the techniques that has been used in many studies but the authentication field still needs to be studied. Blockchain technology is a relatively new technology that has significant research potential related to image authentication. The watermark is embedded into the third-level discrete wavelet transform (DWT) in the middle frequency regions to achieve security and imperceptibility goals. Peak signal-to-noise ratio PSNR, structural similarity matrix (SSIM), normalized correlation coefficient (NCC), and bit error rate (BER) are used to measure the performance of image watermarking. We used blockchain technology to avoid involving a trusted third party for authentication. Secure Hash Algorithm 256 (SHA-256) is applied on the watermark to save it into the blockchain. The watermark is encrypted using Advanced Encryption Standard (AES) and embedded into the image. The proposed method is tested on the USP SICI database and the MedPix medical image database. Ethereum blockchain is used to provide security, anonymity, and integrity of data with no third-party intervention. The proposed solution demonstrates enhanced security for image authentication compared with the state-of-the-art.

Lingyu Bian, Linlin Zhang, Kai Zhao, Hao Wang · 5 authors

In recent years, the rapid development of blockchain technology has attracted much attention from people around the world. Scammers take advantage of the pseudo-anonymity of blockchain to implement financial fraud. The Ponzi scheme, one of the main scam methods, has defrauded investors of large amounts of money, thereby harming their interests and hindering the application of blockchain. Unfortunately, the current detection technology typically largely relies on the source code of the contract or uses a single feature which does not fully represent the contract characteristics. In such a case, the detection of Ponzi schemes with high efficiency becomes urgent. In this paper, we propose an image-based scam detection method using an attention capsule network (SE-CapsNet) focused on Ethereum. The sequence of bytecode, the opcode frequency, and the application binary interface (ABI) call are extracted as features from the contract bytecode and ABI, further converted into grayscale images, and then mapped into three color channels to generate RGB images, which are used as the input of the model for detecting the Ponzi scheme contract. In addition, we employ fancy PCA for data augmentation to reduce the impact of imbalanced data on the detection results. Experimental results show that the image-based detection method using deep learning models can effectively detect contracts before transactions occur. Among them, our proposed SE-CapsNet obtains great detection results, with an F1 score of 98.38%.

Sweeti Sah, B. Surendiran, R. Dhanalakshmi, N. Arulmurugaselvi

No abstract is available for this record.

Vu Trung Duong Le, Thi Hong Tran, Hoai Luan Pham, Duc Khai Lam · 5 authors

The development of low-energy, high-performance hardware for cryptocurrency mining is gaining widespread attention. The mining process for proof-of-work (PoW) in conventional cryptocurrencies’ blockchains is increasingly being replaced by application-specific integrated circuits (ASICs). This leads to many security threats for the blockchain network because it decreases security and increases power consumption for mining. Therefore, Scrypt, the most representative ASIC-resistant algorithm, was developed to solve this problem. However, there are still some problems and challenges with the current Scrypt hardware. This article presents a new hardware architecture for the Scrypt algorithm intended for a PoW-based cryptocurrency mining system. The proposed Multi ROMix Scrypt Accelerator (MRSA) hardware architecture applies several optimization techniques: configuration, local-memory computing with high-performance pipelined Multi ROMix and rescheduling resources to significantly increase processing speed, flexibility, and energy efficiency. For evaluation, the MRSA is implemented on field-programmable gate arrays (FPGAs) to examine its actual performance, consumption, and correctness. Evaluation results on a Xilinx system-on-chip (SoC) with the ALVEO U280 Data Center Accelerator Card FPGA show that the MRSA is much more power-efficient than some of the most powerful commercial CPUs, GPUs, and other FPGA implementations. On the ALVEO U280, the MRSA achieves a maximum hash rate of 296.76 kHash/s, a throughput of 304.9 Mbps when reaching a maximum frequency of 259.94 MHz, and a power consumption of 18.12W. The energy efficiency of the MRSA on the ALVEO U280 SoC is 52.83 and 867.88 times higher than those on an RTX 3090 GPU and an i9-10940X CPU, respectively.

Jeyasheela Rakkini Simon, K. Geetha

The Ethereum blockchain is an open-source, decentralized blockchain with functions triggered by smart contract and has voluminous real-time data for analysis using machine learning and deep learning algorithms. Ether is the cryptocurrency of the Ethereum blockchain. Ethereum virtual machine is used to run Turing complete scripts. The data set concerning a block in the Ethereum blockchain with a block number, timestamp, crypto address of the miner, and the block rewards for the miner are explored for K means clustering for clustering miners with a unique crypto address and their rewards. Linear regression and polynomial regression are used for the prediction of the next block reward to the miner. The Long ShortTerm Memory (LSTM) algorithm is used to exploit the Ether market data set for predicting the next ether price in the market. Every kind of price and volume for every four hours is taken for prediction. The root mean square error of 34.9% is obtained for linear regression, the silhouette score is 71% for K-means clustering of miners with same rewards, with the optimal number of clusters obtained by Gap statistic method.

Fredy Andrés Aponte-Novoa, Ana Lucila Sandoval Orozco, Ricardo Villanueva-Polanco, Pedro M. Wightman

The applications that use blockchain are cryptocurrencies, decentralized finance applications, video games and many others. Most of these applications trust that the blockchain will prevent issues like fraud, thanks to the built-in cryptographic mechanisms provided by the data structure and the consensus protocol. However, blockchains suffers from what is called a 51% attack or majority attack, which is considered a high risk for the integrity of these blockchains, where if a miner, or a group of them, has more than half the computing capability of the network, it can rewrite the blockchain. Even though this attack is possible in theory, it is regarded as hard-achievable in practice, due to the assumption that, with enough active members, it is very complicated to have that much computing power; however, this assumption has not been studied with enough detail. In this work, a detailed characterization of the miners in the Bitcoin and Crypto Ethereum blockchains is presented, with the aim of proving the computing distribution assumption and to creating profiles that may allow the detection of anomalous behaviors and prevent 51% attacks. The results of the analysis show that, in the last years, there has been an increasing concentration of hash rate power in a very small set of miners, which generates a real risk for current blockchains. Also, that there is a pattern in mining among the main miners, which makes it possible to identify out-of-normal behavior.

Mar Gimenez-Aguilar, José M. de Fuentes, Lorena González‐Manzano, Carmen Cámara

Permanent availability makes blockchain technologies a suitable alternative for building a covert channel. Previous works have analysed its feasibility in a particular blockchain technology called Bitcoin. However, Ethereum cryptocurrency is gaining momentum as a means to build distributed apps. The novelty of this paper relies on the use of Ethereum to establish a covert channel considering all transaction fields and smart contracts. No previous work has explored this issue. Thus, a mechanism called$Zephyrus$, an information hiding mechanism based on steganography, is developed. Moreover, its capacity, cost and stealthiness are assessed both theoretically, and empirically through a prototype implementation that is publicly released. Disregarding the time taken to send the transaction to the blockchain, its retrieval and the mining time, experimental results show that, in the best case, 40 Kbits can be embedded in 0.57 s. for US$\$ $1.64, and retrieved in 2.8 s.

Saurabh Singh, A. S. M. Sanwar Hosen, Byungun Yoon

Blockchain technology is becoming increasingly attractive to the next generation, as it is uniquely suited to the information era. Blockchain technology can also be applied to the Internet of Things (IoT). The advancement of IoT technology in various domains has led to substantial progress in distributed systems. Blockchain concept requires a decentralized data management system for storing and sharing the data and transactions in the network. This paper discusses the blockchain concept and relevant factors that provide a detailed analysis of potential security attacks and presents existing solutions that can be deployed as countermeasures to such attacks. This paper also includes blockchain security enhancement solutions by summarizing key points that can be exploited to develop various blockchain systems and security tools that counter security vulnerabilities. Finally, the paper discusses open issues relating to and future research directions of blockchain-IoT systems.

Katarzyna Koptyra, Marek R. Ogiela

Imagechain is a cryptographic structure that chain digital images with hash links. The most important feature, which differentiates it from blockchain, is that the pictures are not stored inside the blocks. Instead, the block and the image are combined together in the embedding process. Therefore, the imagechain is built from standard graphic files that may be used in the same way as any other image, but additionally, each of them contains a data block that links it to a previous element of the chain. The presented solution does not require any additional files except the images themselves. It supports multiple file formats and embedding methods, which makes it portable and user-friendly. At the same time, the scheme provides a high level of security and resistance to forgery. This is achieved by hashing the whole file with embedded data, so the image cannot be altered or removed from the chain without losing integrity. This article describes the basic concept of an imagechain together with building blocks and applications. The two most important issues are embedding methods and block structure.

Amna Qureshi, David Megías

In this paper, we provide a holistic survey of multimedia content protection applications in which blockchain technology is being used. A taxonomy is developed to classify these applications with reference to the technical aspects of blockchain technology, content protection techniques, namely, encryption, digital rights management, digital watermarking and fingerprinting (or transaction tracking), and performance criteria. The study of the literature reveals that there is currently no complete and systematic taxonomy dedicated to blockchain-based copyright protection applications. Moreover, the number of successfully developed blockchain-based content protection systems is very low. This points towards a research gap. To fill this gap, we propose a taxonomy that integrates technical aspects and application knowledge and can guide the researchers towards the development of blockchain-based multimedia copyright protection systems. Furthermore, the paper discusses some technical challenges and outlines future research directions.

Enis Karaarslan, Enis Konacaklı

We have entered an era where the importance of decentralized solutions has become more obvious. Blockchain technology and its derivatives are distributed ledger technologies that keep the registry of data between peers of a network. This ledger is secured within a successive over looping cryptographic chain. The accomplishment of the Bitcoin cryptocurrency proved that blockchain technology and its derivatives could be used to eliminate intermediaries and provide security for cyberspace. However, there are some challenges in the implementation of blockchain technology. This chapter first explains the concept of blockchain technology and the data that we can store therein. The main advantage of blockchain is the security services that it provides. This section continues by describing these services.. The challenges of blockchain; blockchain anomalies, energy consumption, speed, scalability, interoperability, privacy and cryptology in the age of quantum computing are described. Selected solutions for these challenges are given. Remarkable derivatives of blockchain, which use different solutions (directed acyclic graph, distributed hash table, gossip consensus protocol) to solve some of these challenges are described. Then the data storage in blockchain and evolving data solutions are explained. The comparison of decentralized solutions with the lcentralized database systems is given. A multi-platform interoperable scalable architecture (MPISA) is proposed. In the conclusion we include the evolution assumptions of data storage in a decentralized world.