Blockchain Papers

Michał Kędziora, Dawid Pieprzka, Ireneusz J. Jóźwiak, Yongxin Liu · 5 authors

The purpose of this paper is to present mechanisms and algorithms implemented for improving Bitcoin cryptocurrency efficiency and security and to examine the block propagation times from a selected period before and after SegWit was introduced. In this paper, Segregated Witness Implementation issues were verified based both on the simulation and real data from the Bitcoin network. Based on the block propagation times calculated in the simulator, as well as bitcoin network real data, the efficiency and safety of Bitcoin have been analysed and validated.

Bao Nguyen, E. Laxmi Lydia, Mohamed Elhoseny, Irina V. Pustokhina · 8 authors

In present digital era, an exponential increase in Internet of Things (IoT) devices poses several design issues for business concerning security and privacy. Earlier studies indicate that the blockchain technology is found to be a significant solution to resolve the challenges of data security exist in IoT. In this view, this paper presents a new privacy-preserving Secure Ant Colony optimization with Multi Kernel Support Vector Machine (ACOMKSVM) with Elliptical Curve cryptosystem (ECC) for secure and reliable IoT data sharing. This program uses blockchain to ensure protection and integrity of some data while it has the technology to create secure ACOMKSVM training algorithms in partial views of IoT data, collected from various data providers. Then, ECC is used to create effective and accurate privacy that protects ACOMKSVM secure learning process. In this study, the authors deployed blockchain technique to create a secure and reliable data exchange platform across multiple data providers, where IoT data is encrypted and recorded in a distributed ledger. The security analysis showed that the specific data ensures confidentiality of critical data from each data provider and protects the parameters of the ACOMKSVM model for data analysts. To examine the performance of the proposed method, it is tested against two benchmark dataset such as Breast Cancer Wisconsin Data Set (BCWD) and Heart Disease Data Set (HDD) from UCI AI repository. The simulation outcome indicated that the ACOMKSVM model has outperformed all the compared methods under several aspects.

Weizheng Wang, Chunhua Su

No abstract is available for this record.

Xiaofang Li, Yurong Mei, Jing Gong, Feng Xiang · 5 authors

Blockchain is a point-to-point distributed ledger technology based on cryptographic algorithms. However, the open and transparent blockchain ledger supplemented by statistical methods such as sociological mining and data mining has caused users' privacy to face major threats. Therefore, privacy protection has become a focus of current blockchain technology research. Ring signature technology is a commonly used encryption technology in the field of privacy protection. Therefore, this paper constructs a blockchain privacy protection scheme based on ring signature. This solution built a privacy data storage protocol based on the ring signature on the elliptic curve, and used the complete anonymity of the ring signature to ensure the security of data and user identity privacy in blockchain applications. The correctness and safety proof analysis of the proposed scheme were also carried out.

Javier Arcenegui, Rosario Arjona, Iluminada Baturone

No abstract is available for this record.

Ping He, Dunzhe Tang, Jingwen Wang

Proof-of-Stake consensus algorithm solves major drawbacks of PoW blockchain network including high energy consumption and low transaction capacity. However, PoS still faces centralization problems like PoW. In this paper, we propose an economic framework for PoS blockchain network based on staking pool optimization problem and evaluate stake concentration in the network. We prove that stake concentration is encouraged in a finite staking pool PoS blockchain network, but continued consolidation among staking pools is limited and a stable equilibrium always exists where no staking pool has incentive to deviate. Further, we prove that lower pool fixed cost and higher transaction fee raise stable equilibrium pool number and lead to higher network decentralization level. As an extension, we show that wealth discrepancy exacerbates stake centralization while tilted stakeholder selection function mitigates stake centralization.

Dong‐Her Shih, Ting-Wei Wu, Tzu-Hsin Hsu, Po-Yuan Shih · 5 authors

With advancement in computer technology, financial technology has also evolved. Blockchain technology has evolved over the past decade; however, this has also resulted in some malicious attacks. To earn mining rewards of a blockchain, a new type of attack, called cryptojacking, has emerged in the online world. This attack uses the computer resources of a victim to obtain mining rewards without user confirmation. However, this monetization model was originally intended to replace advertising as a source of revenue for a website. To resolve such problems, a storage verification architecture based on smart contracts was proposed in the study. The decentralized system of blockchain enables users to identify and participate in verification of mining sites through Ethereum smart contracts.

Zhang Lejun, Zhijie Zhang, Weizheng Wang, Waqas Rasheed · 7 authors

As an extension of the traditional encryption technology, information hiding has been increasingly used in the fields of communication and network media, and the covert communication technology has gradually developed. The blockchain technology that has emerged in recent years has the characteristics of decentralization and tamper resistance, which can effectively alleviate the disadvantages and problems of traditional covert communication. However, its combination with covert communication thus far has been mostly at the theoretical level. The BLOCCE method, as an early result of the combination of blockchain and covert communication technology, has the problems of low information embedding efficiency, the use of too many Bitcoin addresses, low communication efficiency, and high costs. The present research improved on this method, designed the V-BLOCCE which uses base58 to encrypt the plaintext and reuses the addresses generated by Vanitygen multiple times to embed information. This greatly improves the efficiency of information embedding and decreases the number of Bitcoin addresses used. Under the premise of ensuring the order, the Bitcoin transaction OP_RETURN field is used to store the information required to restore the plaintext and the transactions are issued at the same time to improve the information transmission efficiency. Thus, a more efficient and feasible method for the application of covert communication on the blockchain is proposed. In addition, this paper also provides a more feasible scheme and theoretical support for covert communication in blockchain.

Teppei Sato, Mitsuyoshi Imamura, Kazumasa Omote

No abstract is available for this record.

Hongwei Shi, Shengling Wang, Qin Hu, Xiuzhen Cheng · 6 authors

The pool-hopping attack casts down the expected profits of both the mining pool and honest miners in Blockchain. The mainstream countermeasures, namely PPS (pay-per-share) and PPLNS (pay-per-last-N-share), can hedge pool hopping, but pose a risk to the pool as well as the cost to miners. In this study, we apply the zero-determinant (ZD) theory to design a novel pooled mining which offers an incentive mechanism for motivating non-memorial and memorial evolutionary miners not to switch in pools strategically. In short, our hopping-proof pooled mining has three unique features: 1) fee-free. No fee is charged if the miner does not hop. 2) wide applicability. It can be employed in both prepaid and postpaid mechanisms. 3) fairness. Even the pool can dominate the game with any miner, he has to cooperate when the miner does not hop among pools. The fairness of our scheme makes it have long-term sustainability. To the best of our knowledge, we are the first to propose a hopping-proof pooled mining with the above three natures simultaneously. Both theoretical and experimental analyses demonstrate the effectiveness of our scheme.

Ryunosuke Nagayama, Ryohei Banno, Kazuyuki Shudo

Improving transaction throughput is an important challenge for Bitcoin. However, shortening the block generation interval or increasing the block size to improve throughput makes it sharing blocks within the network slower and increases the number of orphan blocks. Consequently, the security of the blockchain is sacrificed. To mitigate this, it is necessary to reduce the block propagation delay. Because of the contribution of new Bitcoin protocols and the improvements of the Internet, the block propagation delay in the Bitcoin network has been shortened in recent years. In this study, we identify impacts of compact block relay---an up-to-date Bitcoin protocol---and Internet improvement on the block propagation delay and fork rate in the Bitcoin network from 2015 to 2019. Existing measurement studies could not identify them but our simulation enables it. The experimental results reveal that compact block relay contributes to shortening the block propagation delay more than Internet improvements. The block propagation delay is reduced by 64.5% for the 50th percentile and 63.7% for the 90th percentile due to Internet improvements, and by 90.1% for the 50th percentile and by 87.6% for the 90th percentile due to compact block relay.

Gaganjeet Singh Reen, Manasi Mohandas, S. Venkatesan

Electronic Health Records(EHR) are gaining a lot of popularity all over the world. The current EHR systems however have their fair share of problems related to privacy and security. We have proposed a mechanism which provides a solution to most of these problems. Using a permissioned Ethereum blockchain allows the hospitals and patients across the world to be connected to each other. Our mechanism uses a combination of symmetric and asymmetric key cryptography to ensure the secure storage and selective access of records. It gives patients full control over their health records and also allows them to grant or revoke a hospital's access to his/her records. We have used IPFS(inter planetary file system) to store records which has the advantage of being distributed and ensures immutability of records. The proposed model also maintains the statistics of diseases without violating the privacy of any patient.

Sana Sabah Sabry, Nada Mahdi Kaittan, Israa Majeed

As the Bitcoin keeps increasing in value compared to other cryptocurrencies, more attention has been given to Blockchain Technology (BT) which is the infrastructure behind the Bitcoin, especially on its role in addressing the problems of the classical centralized system. As a digital currency, Bitcoin is dependent on the decentralized cryptographic tools and peer-to-peer system. The digital currency implements a distributed ledger using Blockchain when verifying any type of transaction. In this paper, the aim is to describe how digital currency networks such as Bitcoin provides a “trust-less” platform for users to embark on money transfers without necessarily depending on any central trusted establishments such as payment services or financial institutions. Furthermore, this work comprehensively overviewed the basic principle that underly BT, such as transaction, consensus algorithms, and hashing. This study also provided a novel classification for blockchain types according to their system architecture and consensus strategy. For each type, our contribution was provided with an example which clearly describes the blockchain features and the transaction steps. Our classification intended to help researchers understand and choose the blockchain for their application. The paper ends with the discussion of the differences between each type

Vani Rajasekar, J. Premalatha, K. Sathya

Block chain has drawn major attention recently in the area of cyber security. Till to date many detection techniques and protection mechanisms have been proposed to enhance the security. In this paper we have proposed an overview of distributed ledger framework, block chain to defense against the cyber attacks. We here present a comprehensive overview of block chain architecture and some major algorithms used in different block chains. The future trends of block chain technology in the applications such as IoT security, E-voting, Banking sector has also coined out in this paper.

Chenglong Fu, Qiang Zeng, Xiaojiang Du

The booming Internet of Things (IoT) market has drawn tremendous interest from cyber attackers. The centralized cloud-based IoT service architecture has serious limitations in terms of security, availability, and scalability, and is subject to single points of failure (SPOF). Recently, accommodating IoT services on blockchains has become a trend for better security, privacy, and reliability. However, blockchain's shortcomings of high cost, low throughput, and long latency make it unsuitable for IoT applications. In this paper, we take a retrospection of existing blockchain-based IoT solutions and propose a framework for efficient blockchain and IoT integration. Following the framework, we design a novel blockchain-assisted decentralized IoT remote accessing system, RS-IoT, which has the advantage of defending IoT devices against zero-day attacks without relying on any trusted third-party. By introducing incentives and penalties enforced by smart contracts, our work enables "an economic approach" to thwarting the majority of attackers who aim to achieve monetary gains. Our work presents an example of how blockchain can be used to ensure the fairness of service trading in a decentralized environment and punish misbehaviors objectively. We show the security of RS-IoT via detailed security analyses. Finally, we demonstrate its scalability, efficiency, and usability through a proof-of-concept implementation on the Ethereum testnet blockchain.

Muhammad Anwar Hussain, Muhammad Shafie Abd Latiff, Syed Hamid Hussain Madni, Raja Zuraidah Raja Mohd Rasi · 5 authors

Blockchain, Bitcoin's core technology, and spinal cord have received enthusiastic attention since the last couple of decades. The Blockchain serves as a paradigm for distributed and unchangeable computations for bitcoins and cryptocurrencies. The key features behind this technology are to create a reliable, secure, transparent, decentralized, and reliable autonomous ecosystem. It is useful for a variety of applications, especially for legacy devices, resources, and infrastructure. In this article, we presented a technical overview, its application, and the challenges associated with blockchain technology and cryptocurrencies. This study aims to provide a ground-breaking overview and future research direction and promising importance of Blockchain.

Peter Mell, Aurélien Delaitre, Frederic de Vaulx, Philippe Dessauw

Previous work presented a theoretical model based on the implicit Bitcoin specification for how an entity might issue a protocol native cryptocurrency that mimics features of fiat currencies. Protocol native means that it is built into the blockchain platform itself and is not simply a token running on another platform. Novel to this work were mechanisms by which the issuing entity could manage the cryptocurrency but where their power was limited and transparency was enforced by the cryptocurrency being implemented using a publicly mined blockchain. In this work we demonstrate the feasibility of this theoretical model by implementing such a managed cryptocurrency architecture through forking the Bitcoin code base. We discovered that the theoretical model contains several vulnerabilities and security issues that needed to be mitigated. It also contains architectural features that presented significant implementation challenges; some aspects of the proposed changes to the Bitcoin specification were not practical or even workable. In this work we describe how we mitigated the security vulnerabilities and overcame the architectural hurdles to build a working prototype.

Béla Gipp, Norman Meuschke, Joeran Beel, Corinna Breitinger

The proportion of information that is exclusively available online is continuously increasing. Unlike physical print media, online news outlets, magazines, or blogs are not immune to retrospective modification. Even significant editing of text in online news sources can easily go unnoticed. This poses a challenge to the preservation of digital cultural heritage. It is nearly impossible for regular readers to verify whether the textual content they encounter online has at one point been modified from its initial state, and at what time or to what extent the text was modified to its current version. In this paper, we propose a web-based platform that allows users to submit the URL for any web content they wish to track for changes. The system automatically creates a trusted timestamp stored in the blockchain of the cryptocurrency Bitcoin for the hash of the HTML content available at the user-specified URL. By using trusted timestamping to secure a ‘snapshot’ of online information as it existed at a specific time, any subsequent changes made to the content can be identified.

Authors unavailable

On considering the integrity of electronic evidence, in particular,we can see that such evidence needs to be protected from a number of undesirable outcomes namely, alteration or destruction. We need to guard against these events and others when trying to maintain system integrity and preserve the purity of evidence so that it could be acceptable in the court. Chain of Custody is nothing but the consecutive documentation of records. The Chain of Custody has all the necessary steps that a crime investigator must follow to make sure whether the information is honest. The Chain of Custody is significant because it cannot be proven that evidence was not altered during the time between collection and its usage in court. Then the collected evidence is not credible. Blockchain technology,a decentralized network currently used by Bitcoins and other Cryptocurrency networks, helps provide a secure database with the help of hashing the data and storing it in blocks.We propose to implement blockchain technology for the process of Chain of Custody, which helps in tracking the people whoaccess the data and assist in assuring the credibility of the data provided during the time of submission in court.

Shengmin Xu, Jiaming Yuan, Yingjiu Li, Ximeng Liu · 5 authors

Payment channel with penalizing double-spending has been widely applied in cryptocurrencies for achieving fast payment. However, current payment channel solutions suffer at least one of the following problems: 1) large overheads and communication costs are incurred to thwart double-spending; 2) payees must be defined before building payment channels; 3) a single payment channel does not support multiple payees; 4) no formally theoretical proofs are provided for the security of payment channels (as an open problem mentioned in CCS'15). In this paper, we fill these gaps by introducing a new fast payment protocol named super payment channel. We provide detailed construction based on digital signatures and accountable assertions with formal security proofs. We also implement our proposed protocol in different circumstances and demonstrate that our proposed protocol incurs a small overhead compared to ordinary Bitcoin transactions.

Nasser Alsalami, Bingsheng Zhang

Blockchain and cryptocurrencies have been widely deployed and used in our daily life. Although there are numerous works in the literature surveying technical challenges and security issues in blockchains, very few works focused on the anonymity guarantees provided in cryptocurrencies. In this work, we conduct a systematic survey on anonymity in cryptocurrencies with a clear categorization for the different tiers of anonymity offered in the various cryptocurrencies as well as their known weaknesses and vulnerabilities. We also study the techniques that have been used to achieve each tier of anonymity. Finally, we asses the current techniques, and present a forecast for the technological trends in this field.

Noor Abdalkarem Mohammedali, Ali Al-Sherbaz

There is no uncertainty that the chroma currency is very popular for the transaction information stored in the block of blocks. To initiate the importance of blocking, there is only one distributed ledger in which data is stored, since many of the centers in the blockchain network limit enough records for these records. This document proposes a decision-making framework based on innovation to create a secure, unjustifiable, accurate and transparent framework for voter privacy. In addition, it is voted and declared in this context that the race has a short period of time, since it is automatically registered in the table. This framework also gives society confidence in its legislation when applying this technique. In this framework, an administrator can add a candidate and a voter to the block. In different hands, a voter can log into the framework and then decide in favor of a candidate that the details of the vote should be stored in the block. In addition, each square in the blockchain innovation that relates to the previous square contains the hash of the previous square, and each square contains explicit data based on the square footage. The hub is connected by a peer network in this framework, with all the hubs in the block site network that have a complete duplicate block.

Angelica Lo Duca, Clara Bacciu, Andrea Marchetti

Negli ultimi anni la tecnologia blockchain si sta diffondendo sempre più su larga scala in diversi settori di ricerca, inclusi i Beni Culturali. Esistono diverse tipologie di blockchain, che possono essere classificate sia in base al tipo di utenti che possono accedervi, sia in base alle funzionalità che offrono. Questo articolo descrive uno studio teorico in cui si confrontano due blockchain molto diverse tra di loro: Ethereum e Hyperledger, al fine di definire quale delle due è maggiormente indicata per la memorizzazione di beni culturali tangibili contenuti in archivi digitali. Dopo una breve descrizione delle due tecnologie, verrà descritto un possibile scenario di applicazione abbastanza generico per poter capire quale delle due tecnologie meglio soddisfa i requisiti. Verrà quindi effettuato il confronto tra le due blockchain sulla base di problematiche generali, requisiti architetturali e considerazioni varie. Come risultato del confronto, emergerà che Hyperledger Fabric è più adatta nel contesto degli archivi digitali.

Kazi Sadia, Md Masuduzzaman, Rajib Kumar Paul, Anik Islam

Voting is a very important issue which can be beneficial in term of choosing the right leader in an election. A good leader can bring prosperity to a country and also can lead the country in the right direction every time. However, elections are surrounds with ballot forgery, coercion and multiple voting issues. Moreover, while giving votes, a person has to wait in a long queue and it is a very time consuming process. Blockchain is a distributed database in which data are shared with the participant of the node and each participant holds the same copy of the data. Blockchain has properties like distributed, pseudonymous, data integrity etc. In the paper, a fully decentralized evoting system based on blockchain technology is proposed. This protocol utilizes smart contract into the evoting system to deal with security issues, accuracy and voters privacy during the vote. The protocol results in a transparent, non editable and independently verifiable procedure that discards all the intended fraudulent activities occurring during the election process by removing the least participation of the third party and enabling voters right during the election. Both transparency and coercion are obtained at the same time.