Blockchain Papers

Sirine Sayadi, Sonia Ben Rejeb, Zièd Choukair

With the increasing number of connected devices and the number of online transactions today, managing all these transactions and devices and maintaining network security is a research issue. Current solutions are mainly based on cloud computing infrastructures, which require servers high-end and broadband networks to provide data storage and computing services. These solutions have a number of significant disadvantages, such as high maintenance costs of centralized servers, critical weakness of Internet Of Things applications, security and trust issues, etc. The blockchain is seen as a promising technique for addressing the mentioned security issues and design new decentralization frameworks. However, this new technology has a great potential in the most diverse technological fields. In this paper, we focus on presenting an overview of blockchain technology, highlighting its advantages, limitations and areas of application. The originality of this work resides in the comparison between the different blockchain systems and their security schemes and the perspective of integrating this technology into secured systems models for our comfort and our private life.

Aaron Brown

Why Cryptos are more likely than not to succeed.

Irani Acharjamayum, Ripon Patgiri, Dhruwajita Devi

The underlying or core technology of Bitcoin cryptocurrency has become a blessing for human being in this era. Everything is gradually changing to digitization in this today's epoch. Bitcoin creates virtual money using Blockchain that's become popular over the world. Blockchain is a shared public ledger, and it includes all transactions which are confirmed. It is almost impossible to crack the hidden information in the blocks of the Blockchain. However, there are certain security and technical challenges like scalability, privacy leakage, selfish mining, etc. which hampers the wide application of Blockchain. In this paper, we briefly discuss this emerging technology namely Blockchain. In addition, we extrapolate in-depth insight on Blockchain technology.

Alka Vishwa, Farookh Khadeer Hussain

There has been a vast increase in incidents related to multimedia copyright and security breaches in the past few years, compromising users' privacy. One such breach involved the seventh season of the TV series “Game of Thrones”, where episodes were illegally downloaded before the official release date etc. Such security breaches raise questions about the approaches and models that currently apply to data privacy and security, where the user saves and distributes his data personally or depends on a third party or stakeholder to manage the distribution rights of sensitive data. When it comes to multimedia, many companies or multimedia owners rely on third parties, distributors and sales persons to monitor their publicity, maintain their popularity and sell their multimedia content. Blockchain technology, which was originally devised for the digital currency (cryptocurrency), has distinct features such as distributed networking, data privacy, trust less computing etc. This technology attracts great interest from the research community due to its innovative properties which can be applied to many business applications, one being access control over data. In this paper, we present a decentralized data management framework that ensures user data privacy and control. We propose a protocol that uses blockchain technology to take control of the user's data. This protocol enables the user to have full control over his multimedia files and he doesn't need to trust a third party. The framework allows the user to not only store data but also to query and share data as well as auditing. Finally, we discuss possible future extensions of blockchain technology as a medium to ensure privacy, data control, auditing and trust management in different areas.

Michael Kerr, Fengling Han, Ron van Schyndel

Presented here is a functional implementation of Distributed Ledger Technology applied to the task of cataloguing CCTV video evidence. We describe and demonstrate a prototype camera that participates in blockchain creation in real time, and the system designed to manage and coordinate its distribution and use. This application is of specific interest to law enforcement agencies charged with the management of high volumes of CCTV evidence. We discuss applicability and scalability with reference to simulation results and real-world testing. The combination of blockchain technology with a novel digital watermarking application is demonstrated here providing immediate benefit against an existing real-world problem of trustworthy evidence protection in distributed network environments.

Matthew Frederick, Chetan Jaiswal

The growth of technology has brought upon a slew of devices that have the ability to connect to the internet. This has led to much more opportunistic and easier ways to perform tasks but it also opens the doors for new attacks. Blockchaining is a new technology that was introduced with the creation of Bitcoin in 2008. Blockchaining has mostly been implemented in the field of cryptocurrency but there are many other useful applications of blockchaining. It allows for a decentralized ledger of data that can securely keep a network honest and prevent from possible attacks. Blockchains are based on a consensus algorithm and the proof of stake algorithm bases consensus between nodes based on the stake that the nodes have in the system.

Deepa Pavithran, Rajesh Thomas

Global payment systems powered by blockchain technology through various cryptocurrencies like Bitcoin, Litecoin, Ethreum are growing rapidly providing public access to its database. The technology eliminates the need for a central authority like bank to control the data. Instead, verification and integrity of data are provided through cryptographic techniques. Bitcoin is not a monetary generated by a government. Analyzing the public dataset and exploring its statistical property can uncover some hidden facts in cryptocurrency and the blockchain protocol. There are two underlying motivations for us to write this survey. First is to provide an up-to-date literature survey on Bitcoin transaction analysis, and second is to understand the hidden facts that could be revealed by analyzing Bitcoin transactions. To provide a comprehensive survey, we categorize existing analysis based on anonymity, user behavior, wealth accumulation and currency rate prediction. Analyzing the Bitcoin transactions can help to understand it from a broader perspective that can help investors in decision making.

Xiaojing Zhang, Rui Qin, Yong Yuan, Fei–Yue Wang

Bitcoin is a decentralized peer-to-peer electronic cash system, and it realizes the circulation and distribution of cryptocurrency via miners contributing their computational power to solve a cryptographic puzzle. With more and more people participating in Bitcoin mining, the continuous growing of the computational power might greatly reduce the time for finding a new valid block. To keep the stability of the Bitcoin system, the difficulty of the Bitcoin network will be adjusted every 2016 blocks. This paper aims to study the principles of the difficulty adjustment of the whole Bitcoin blockchain network in Bitcoin mining. We first describe the computing process of the target and thus the difficulty of a block, and then study its influence factors and their effect on the difficulty. After that, we study the adjustment of the difficulty, and propose a framework for the adjustment of the difficulty that can be easily used in practice. Our work can help researchers better understand the principles of Bitcoin mining.

I Gusti Ayu Kusdiah Gemeliarana, Riri Fitri Sari

Bitcoin is one of the first implementations of cryptocurrency or digital currency. It uses has increased in recent years along with the increasing volume of online transactions that require digital currency A blockchain is a digital ledger that allows parties to transact without use of a central authority as a trusted intermediary. In blockchain, there are a number of consensus protocols proposed including Proof of Stake, Proof of Elapsed Time, but most of the existing blockchain utilizes the computed Proof of Work (PoW) mechanism. Transaction security is secured in Bitcoin by using blocks with a hash-based Proof of Work (PoW) mechanism. PoW is a functional protocol that validates every incoming data to overcome spam attacks and Distributed Denial of Service (DDoS) attacks. Blockchain technology can store historically decentralized transaction data where each connected computer will store exactly the same data. To be able to perform an optimal transaction process, it is necessary to evaluate performance of the POW blockchain and find out what influences the transaction process. In this study, we compare simulation result of different block size and block interval to Block Propagation Time, time setup, and Average upload/download with selfish mining attack using NS3. The experimental results show that the smaller the block interval and block size, the smaller the Block Propagation time. It means that faster transactions are confirmed to peers on the network, and this affects the upload/download speeds.

Puneet Puneet, Aman Chaudhary, Nitin Singh Chauhan, Abhishek Kumar

In centralized environments, the results of voting events have always been questionable and perceived differently by voters. Most existing E-Voting systems are based on centralized servers where the voters must trust the organizing authority for the integrity of the results. In this paper we propose a novel approach for a decentralized trustless voting platform that relies on Blockchain technology to solve the trust issues. The main features of this system include ensuring data integrity and transparency, and enforcing one vote per mobile phone number for every poll with ensured privacy. To accomplish this, the Ethereum Virtual Machine (EVM) is used as the Blockchain runtime environment, on which transparent, consistent and deterministic smart contracts will be deployed by organizers for each voting event to run the voting rules. Users are authenticated through their mobile phone numbers without the need of a third party server. Results showed that the system is feasible and may offer a step towards ideal environments for such experience.

Oğuzhan TAŞ, Farzad Kiani

Son zamanlarda; blok zinciri tabanlı kripto para ödeme sistemleri(bitcoin, ethereum) oldukça popüler olmuştur. Merkezi olmayan eşler arası(P2P) ağ yapısına sahip olan bu sistemde tüm işlemler, sadece ekleme yapılabilen bir ana defterde(ledger) tutulmaktadır. Madenciler ise bu ağ yapısındaki düğümleri oluşturmaktadır, her madenci defterin yerel kopyasına sahiptir. Blok zincirinde, PoW uzlaşma protokolü işlemi onaylamakta ve zincire yeni blok eklenmesine izin vermektedir. Ödülü almak için, madenciler eşler arası ağda işlemi tamamlamak için birbirleriyle yarışırlar. Ödül sistemi, blok zinciri kullanan bitcoin’i popülerleştirmiş, fakat aynı zamanda saldırganların blok zincirine ilgisini artırmıştır. Saldırganlar tarafından blok zincirinin madenci havuzuna ve ağ yapısının güvenliğine farklı saldırılar yapılmıştır. Bu makalede, blok zinciri alt yapısına karşı mevcut saldırılar sunulmuştur. İlk bölümlerde, P2P mimarisine, uzlaşma protokolüne ve işlemlere yönelik saldırı tipleri araştırılmıştır. Bu bölümde, %51 saldırısı, Çift harcama, Finney, Vector76, Kaba Kuvvet, Sybil, Eclipse, Denge gibi saldırılar açıklanmış ve çözümler önerilmiştir. Daha sonra, Bencil madencilik ve Blok Atma, Blok Tutma(BWH), Blok Tutma Sonrası Çatallanma(FAW), Havuz sıçrama saldırısı, Cezalandırıcı Çatallanma ile Kara Listeye Alma, Köpük saldırısı ve Rüşvet Saldırısı gibi madencilik havuzuna karşı saldırılar incelenmiş ve savunma stratejileri sunulmuştur. Son bölümde de blok zinciri altyapısında kullanılan kriptografi’nin geleceği üzerinde tartışılmış ve Post Kuantum Kriptografi’nin etkilerinden bahsedilmiştir

Yong Yu, Yujie Ding, Yanqi Zhao, Yannan Li · 7 authors

Currently, the number of Internet of Thing (IoT) devices making up the IoT is more than 11 billion and this number has been continuously increasing. The prevalence of these devices leads to an emerging IoT business model called Device-as-a-service(DaaS), which enables sensor devices to collect data disseminated to all interested devices. The devices sharing data with other devices could receive some financial reward such as Bitcoin. However, side-channel attacks, which aim to exploit some information leaked from the IoT devices during data trade execution, are possible since most of the IoT devices are vulnerable to be hacked or compromised. Thus, it is challenging to securely realize data trading in IoT environment due to the information leakage such as leaking the private key for signing a Bitcoin transaction in Bitcoin system. In this paper, we propose LRCoin, a kind of leakage-resilient cryptocurrency based on bitcoin in which the signature algorithm used for authenticating bitcoin transactions is leakage-resilient. LRCoin is suitable for the scenarios where information leakage is inevitable such as IoT applications. Our core contribution is proposing an efficient bilinear-based continual-leakage-resilient ECDSA signature. We prove the proposed signature algorithm is unforgeable against adaptively chosen messages attack in the generic bilinear group model under the continual leakage setting. Both the theoretical analysis and the implementation demonstrate the practicability of the proposed scheme.

Siamak Solat

A blockchain is a decentralized ledger where all transactions are recorded. For having a reliable blockchain and double-spending prevention, we need a decentralized consensus and agreement on a blockchain. Bitcoin uses proof-of-work (PoW). It is a cryptographic puzzle that is difficult to solve but easy to verify. However, because of significant latency of proof-of-work for transactions confirmation, this consensus mechanism is vulnerable against double-spending. On the other hand, PoW consumes a significant amount of energy that by growing the network, it becomes a major problematic of this consensus mechanism. In this paper, we introduce an alternative to PoW, because of all its major problems and security issues that may lead to collapsing decentralization of the blockchain, while a full decentralized system is the main purpose of using blockchain technology. The approach we introduce is based on a distributed voting process and called "RDV: Register, Deposit, Vote". Since in RDV algorithm, there is no mining process, so it is appropriate for low-level energy devices and Internet of Things (IoT).

Hiroki Watanabe, Shigenori Ohashi, Shigeru Fujimura, Atsushi Nakadaira · 6 authors

Bitcoin's enormous success has inspired the development of alternative blockchains, such as consortium chains. Several cross-chain protocols have been proposed as ways of connecting these universes of individual blockchains in a distributed and secure manner. In this paper, we present Niji, a new cross-chain protocol that allows parties to perform virtual Bitcoin payment securely on a consortium chain, without any trusted third-party or mediators. Our work focuses on the issue that it is difficult for a consortium chain's token to hold a stable market value, and Niji makes it possible for smart contract services to acquire means of payment in the consortium chain. With the Bitcoin payment channel built on the consortium chain, the process from payment to service provision runs autonomously without any interaction between parties. Niji introduces the concept of a transaction template to validate Bitcoin payments efficiently on different blockchains, and it allows a service provider to delegate all of its tasks for verifying state updates to a smart contract on the consortium chain. We also propose a novel bi-directional payment channel adapted for design of the Niji protocol, which can update payments non-interactively between parties. We implemented a prototype of the Niji protocol and conducted an experiment measuring the computational cost and latency that demonstrates the protocol's feasibility on practical platforms.

Lin Zhong, Qianhong Wu, Jan Xie, Jin Li · 5 authors

No abstract is available for this record.

Mahmoud Al-Rawy, Atilla Elçi

No abstract is available for this record.

Jaehong Ahn, Mingyu Park, Jeongyeup Paek

E-commerce has become an essential part of our life allowing us to buy products, request services, and transfer money easily with a press of a button. In general, people consider various factors of a product like price, quality, etc. before making purchases. When it comes to choosing one of the sellers having a same product with similar price, customers pay attention to each seller's reputation or the degree of trust to the seller. On the existing online payment systems, however, information such as reputation could be manipulated by the malicious (including the advertisers) giving extremely high or low ratings on purpose. Furthermore, as each individual has different criteria on ways to evaluate, the result value of reputation could be non-objective resulting in unreliability of data.In this paper, we propose Reptor, a model for calculation of trust and reputation with the values stored on blockchain-based payment system's ledger. Reptor is applied on blockchain-based online payment system which has a characteristic of immutability. Reptor normalizes the evaluations given by each user based on personal evaluation criteria changing over time. In addition, Reptor derives reputation of users and trust of one to another by applying psychological factors. Simulation results show that our Reptor is able to derive robust and objective values from immutable transactions on blockchain-based online payment system.

ChangHyung Lee, Lewis Nkenyereye, Nak-Myoung Sung, JaeSeung Song

With the growth of Internet-of-Things (IoT), Machine-to-machine (M2M) communications is a key factor to enable the IoT paradigm. Several Standards Development Organizations (SDOs) including oneM2M are working on specifications that will enable interoperability for the M2M within the IoT ecosystem. However, the transactions within the IoT platform are not trustworthy due to its centralized structure. In the meanwhile, blockchain technologies have emerged as a revolutionary technology with a wide range of applications. In this paper, we present an architectural framework that aims at enabling blockchain in IoT platform. We consider a oneM2M-based IoT platform and an existing blockchain system namely Logchain that uses the blind voting algorithm as a consensus rule to ensure the integrity of the blocks. We discuss the proposed framework by highlighting the key points that are achieved through the architecture. We then present the concluding remarks and our future work.

Wanjun Yu, Wu Yuan

Blockchain technology is actually a distributed database technology. It adopts a series of security technologies such as P2P network technology, asymmetric encryption technology and smart contract technology to ensure the security and reliability of transactions. It has advantages of decentralization, anonymity and traceability. In view of the problems existing in the current centralized network transaction mode, this paper creatively proposes the design scheme of “network trading system based on blockchain technology”, and proposes a safe and feasible network transaction system model to ensure the transaction in network data transmission, data processing and other aspects of security. In-depth research and elaboration of some key technologies and principles in the network trading system. Comprehensive application of P2P network technology, asymmetric encryption technology, consensus mechanism, smart contract and other technologies to solve the security problem of network transaction systems. The specific implementation process is given for the transaction system from the aspects of demand analysis, transaction process, interface design, data model design and storage scalability design. Finally, it summarizes the application of blockchain technology in network transactions and points out the future research direction.

Nikita Sanghi, Rupali Bhatnagar, Gaganjot Kaur, Vinay Jain

In this world of digitalization, if you want to deliver digital services of any kind, Cloud Computing has emerged as an invincible technology. It anticipates on shared computing resources instead of setting up local servers to manage, store and process data. It is in preference these days because of its convenience, scalability, low cost, easy accessibility and high availability. There are few security concerns which arise while using Cloud Computing. This paper analyses Cloud Computing using framework of blockchain for different problems faced in Cloud computing. A block chain is an uninterrupted list of records, called blocks that are associated with each other and secured by making the use of cryptography. The risks and difficulties associated with Cloud Computing are manifested so as to explain why block chain is disruptive and justified technology in solving the concern and how electronic wallets which work on principle of blockchain in cloud computing environments preserves user data integrity. A detailed indexing of applications is also being presented, keeping in mind the recent progress in the field of technologies.

Syeda Mariam Muzammal, Raja Kumar Murugesan

In the rapidly growing digital and technological world, Internet of Things (IoT) is becoming very popular and widely implemented. As more and more IoT devices are deployed in an uncontrolled, complex and often hostile environment, securing the IoT devices, systems and data exchange presents numerous unique challenges. With data sensitive IoT applications, there is an utmost need to protect and explore user privacy, access control, third party involvement, and Machine-to-Machine (M2M) information exchange in order to avoid critical security breach and cyberattacks. Most of the security and privacy issues of the interconnected heterogeneous resource constrained smart IoT devices are unable to be solved efficiently by traditional security practices. On the other hand, Blockchain technology is well-thought-out as emerging and revolutionary concept, initiated from cryptocurrency, and now making way to enhance various scenarios in digital paradigm, mainly due to its decentralized nature and transparency. This paper reviews the adoption of IoT in various fields and its applications to automate and improve living conditions, along with security and privacy risks arising from organization and functioning of different IoT components. Moreover, the study is specifically based on how effectively the Blockchain technology can be leveraged for strengthening IoT security and privacy implications, and possible limitations of embedding Blockchain with IoT framework.

Jing Long, Dafang Zhang, Wei Liang, Kuan‐Ching Li

Protection of IPs through watermarking techniques is prevalent to prevent IP infringement. In previous researches, authentication of watermark in IPs easily disclosures sensitive information of real embedded watermarks, where the evidence of identifying IP ownership may be attacked by illegal verifiers. Despite several watermark detection techniques can address the disclosure of sensitive information in detection procedure, the efficiency for such a detection remains relatively low. Besides, it may yield to large communication overhead on multiple authentication rounds. Motivated by the needs of robustness and efficiency, it is proposed in this work a leakage-resilient protocol to authenticate ownership of Field Programmable Gate Array (FPGA) bitfile design using zero-knowledge proof. The prover can convince the verifier that he knows a secret in the suspected bitfile design via only one interaction. Real locations of watermarks are concealed through location anonymity. With the received authentication package from the prover, the verifier cannot obtain other useful information about watermarks. From experiments, we show that the proposed authentication technique achieves high efficiency and robustness on watermark detection.

Bellia Dwi Cahya Putri, Riri Fitri Sari

Bitcoin holds the largest market share among all digital currencies. Transaction security is secured in Bitcoin by using blocks with a hash-based Proof of Work (PoW) mechanism. Bitcoin PoW takes an average of 10- minutes to complete and 6 consecutive blocks are recommended for a single transaction in the system. PoW is a functional protocol that validates every incoming data to overcome spam attacks and DDoS attacks (Distributed Denial of Service). Selfish miner is an attack on the integrity of the Bitcoin network. The selfish miner succeeds because the honest miners are forced to spend part of their computing cycle on blocks that are destined not to be in the public chain. To achieve higher scalability, network latency must be low, that is the time required for the protocol to confirm the transaction should be effectively reduced. In this study, the author will make a simulation of the effect of latency on block receive time on Bitcoin with selfish-miner attack using NS3. The experimental results show the use of the latency variation and the more number of generated blocks, the lower the MBRT value. The average MBRT of each parameter shows the required receive time by the block number of about 15 minutes to 16 minutes. This amount exceeds the PoW's tolerance time limit when making a transaction. This is due of selfish-miner attack and Latency.

Chanhyung Lee, Nak-Myoung Sung, Lewis Nkenyereye, JaeSeung Song

The Internet of things(IoT) is predicted to connect millions of devices. Therefore, standardized IoT technologies play a crucial role connecting massive IoT devices with interoperability. Various Standards Development Organizations (SDO) are working towards a horizontal solution that would fit several vertical platforms including oneM2M global IoT service layer standards initiative. Blockchain is a distributed ledger technology which is being applied in diverse applications such as crypto currency and smart contract. In this demo, we develop a blockchain-enabled IoT service layer platform based on oneM2M IoT standards and an blockchain hybrid application. We use a blockchain system named Logchain that is suitable for IoT due to its consensus algorithm. The hybrid application and oneM2M optional attribute added to the IoT platform enables the IoT users to either store their data in a conventional database or distributed ledger database.