Blockchain Papers

Michael Kerr

This research explores Law Enforcement Agency (LEA) applications for digital watermarking performed on the camera in real time, combining this with Distributed Ledger Technology (DLT) to suggest workable systems for data cataloguing and image integrity. Reference implementations of both technologies are developed and evaluated for their effectiveness and suitability for these purposes.

Gaurav Deep, Rajni Mohana, Anand Nayyar, Sanjeevikumar Padmanaban · 5 authors

Cloud computing has made the software development process fast and flexible but on the other hand it has contributed to increasing security attacks. Employees who manage the data in cloud companies may face insider attack, affecting their reputation. They have the advantage of accessing the user data by interacting with the authentication mechanism. The primary aim of this research paper is to provide a novel secure authentication mechanism by using Blockchain technology for cloud databases. Blockchain makes it difficult to change user login credentials details in the user authentication process by an insider. The insider is not able to access the user authentication data due to the distributed ledger-based authentication scheme. Activity of insider can be traced and cannot be changed. Both insider and outsider user's are authenticated using individual IDs and signatures. Furthermore, the user access control on the cloud database is also authenticated. The algorithm and theorem of the proposed mechanism have been given to demonstrate the applicability and correctness.The proposed mechanism is tested on the Scyther formal system tool against denial of service, impersonation, offline guessing, and no replay attacks. Scyther results show that the proposed methodology is secure cum robust.

Hsin‐Te Wu, Chun‐Wei Tsai

Countries around the world are nowadays actively promoting development in intelligent agriculture. Each of them must develop a specific plan tailored to environmental farming indices of each individual farm, and such information would be both important and sensitive. This is why information in intelligent agriculture requires protection from network security to ensure data privacy and integrity. This study proposes applying dark web technology to ensure the privacy of blockchains and servers. The study will monitor packet transmission frequency in intelligent agriculture to prevent distributed denial-of-service (DDOS) attacks. The main features of system include: (1) An identity authentication mechanism, (2) secure transmission of information, (3) establishment of private blockchains, (4) a faster, improved authentication system for blockchain information, and (5) resistance against DDOS attacks. The proposed scheme can safeguard network security for the IoT as well as the servers by way of applying dark web technology, which can avoid exposure of blockchains and server ID addresses and thus in turn lower the risks of DDOS attack damages. Experiment results indicate that the application of lightweight encryption of proposed scheme does indeed improve the authentication speed while also satisfying requirements of network security.

V. Suma

Block chain being a foundational technology impacting and attracting a wide range of applications has become predominant in solving the problem of privacy preserving and security in multitude sectors that is under the control of the government and the private. The paper also presents the security and the privacy mechanism using the block chain to prevent the misuse and the corruption in the sharing of huge set of data generated from the judiciary, security, legislature, commercial code registries etc. The proposed system enables reliability and the trust in the data sharing in the communication channels utilizing the block chain with the RSA digital signature. The proposed system is simulated as a java programming version to evince the enhancement in the latency in the sharing of the information's along with the privacy and the security

Scott Ruoti, Benjamin Kaiser, Arkady Yerukhimovich, Jeremy Clark · 5 authors

Bitcoin's success has led to significant interest in its underlying components, particularly Blockchain technology. Over 10 years after Bitcoin's initial release, the community still suffers from a lack of clarity regarding what properties defines Blockchain technology, its relationship to similar technologies, and which of its proposed use-cases are tenable and which are little more than hype. In this paper we answer four common questions regarding Blockchain technology: (1) what exactly is Blockchain technology, (2) what capabilities does it provide, and (3) what are good applications for Blockchain technology, and (4) how does it relate to other approache distributed technologies (e.g., distributed databases). We accomplish this goal by using grounded theory (a structured approach to gathering and analyzing qualitative data) to thoroughly analyze a large corpus of literature on Blockchain technology. This method enables us to answer the above questions while limiting researcher bias, separating thought leadership from peddled hype and identifying open research questions related to Blockchain technology. The audience for this paper is broad as it aims to help researchers in a variety of areas come to a better understanding of Blockchain technology and identify whether it may be of use in their own research.

Amie Corso

Blockchains are distributed ledgers that use a tamper-sensitive, append-only data structure in conjunction with a consensus protocol to enable mutually distrusting parties to maintain a global set of states. A primary barrier to adoption of blockchain technology by industry is the current performance and scalability limitations of these systems, which lag far behind incumbent database systems. Of particular interest are “lottery-style” consensus algorithms, which are relatively scalable to many participants but suffer from low throughput (performance). Proof-of-Elapsed-Time (PoET) is one such algorithm with great promise for use in industry, though the parameters that govern its performance have not been well studied. This thesis explores, through simulation, key performance outcomes in PoET blockchain networks implemented with the Hyperledger Sawtooth framework. A better quantitative understanding of the interactions among these system parameters will be crucial for efficiently optimizing real world blockchain networks and facilitating adoption by industry.

Spurthi Anjan, Johnson P Sequeira

With the current rise in the demand and usage of the blockchain technology for a variety of purposes, ranging from finance, medical, identification amongst others, major focus has been dedicated towards its legal implications rather than leveraging on the practical applications in administration. In this paper, we discuss the concepts of blockchain and how it can be implemented as an efficient solution towards public voting while aiming to destroy the disadvantages of the current voting system in India, at the same time providing a better, more reliable, secure and transparent means of public governance. We also aim to provide an exemplified voting solution for India with the integration of the current Aadhaar identification system as implemented by UIDAI.

Zhimin Gao, Lei Xu, Keshav Kasichainula, Lin Chen · 6 authors

Bitcoin brings a new type of digital currency that does not rely on a central\nsystem to maintain transactions. By benefiting from the concept of\ndecentralized ledger, users who do not know or trust each other can still\nconduct transactions in a peer-to-peer manner. Inspired by Bitcoin, other\ncryptocurrencies were invented in recent years such as Ethereum, Dash, Zcash,\nMonero, Grin, etc. Some of these focus on enhancing privacy for instance crypto\nnote or systems that apply the similar concept of encrypted notes used for\ntransactions to enhance privacy (e.g., Zcash, Monero). However, there are few\nmechanisms to support the exchange of privacy-enhanced notes or assets on the\nchain, and at the same time preserving the privacy of the exchange operations.\nExisting approaches for fair exchanges of assets with privacy mostly rely on\noff-chain/side-chain, escrow or centralized services. Thus, we propose a\nsolution that supports oblivious and privacy-protected fair exchange of crypto\nnotes or privacy enhanced crypto assets. The technology is demonstrated by\nextending zero-knowledge based crypto notes. To address "privacy" and\n"multi-currency", we build a new zero-knowledge proving system and extend note\nformat with new property to represent various types of tokenized assets or\ncryptocurrencies. By extending the payment protocol, exchange operations are\nrealized through privacy enhanced transactions (e.g., shielded transactions).\nBased on the possible scenarios during the exchange operation, we add new\nconstraints and conditions to the zero-knowledge proving system used for\nvalidating transactions publicly.\n

Weizhao Tang, Weina Wang, Giulia Fanti, Sewoong Oh

Payment channel networks (PCNs) are viewed as one of the most promising scalability solutions for cryptocurrencies today. Roughly, PCNs are networks where each node represents a user and each directed, weighted edge represents funds escrowed on a blockchain; these funds can be transacted only between the endpoints of the edge. Users efficiently transmit funds from node A to B by relaying them over a path connecting A to B, as long as each edge in the path contains enough balance (escrowed funds) to support the transaction. Whenever a transaction succeeds, the edge weights are updated accordingly. In deployed PCNs, channel balances (i.e., edge weights) are not revealed to users for privacy reasons; users know only the initial weights at time 0. Hence, when routing transactions, users typically first guess a path, then check if it supports the transaction. This guess-and-check process dramatically reduces the success rate of transactions. At the other extreme, knowing full channel balances can give substantial improvements in transaction success rate at the expense of privacy. In this work, we ask whether a network can reveal noisy channel balances to trade off privacy for utility. We show fundamental limits on such a tradeoff, and propose noise mechanisms that achieve the fundamental limit for a general class of graph topologies. Our results suggest that in practice, PCNs should operate either in the low-privacy or low-utility regime; it is not possible to get large gains in utility by giving up a little privacy, or large gains in privacy by sacrificing a little utility.

Hajar Moudoud, Soumaya Cherkaoui, Lyes Khoukhi

The blockchain is a distributed technology which allows establishing trust among unreliable users who interact and perform transactions with each other. While blockchain technology has been mainly used for crypto-currency, it has emerged as an enabling technology for establishing trust in the realm of the Internet of Things (IoT). Nevertheless, a naive usage of the blockchain for IoT leads to high delays and extensive computational power. In this paper, we propose a blockchain architecture dedicated to being used in a supply chain which comprises different distributed IoT entities. We propose a lightweight consensus for this architecture, called LC4IoT. The consensus is evaluated through extensive simulations. The results show that the proposed consensus uses low computational power, storage capability and latency.

Mohamad Hafizat Zainal Abidin, Saravid Suchaad, Koichiro Mashiko, Nordinah Ismail

Internet of things (IoT) is becoming increasingly important and ubiquitous in home and industries. It makes object a part of the Internet and fuses the digital and physical world together. However, if not properly secured, IoT device can be vulnerable to tampering that can change the content of the data stored in the network. Blockchain, a technology used in cryptocurrency, can be used for addressing the security and privacy challenges in IoT. Blockchain can be beneficial to IoT by adding more security layer and reducing dependency on a central authority. This paper proposed to develop a blockchain based platform for IoT application. Blockchain technology can be utilized to provide a decentralized network, creating a more secured IoT system. The proposed blockchain network will be based on Ethereum blockchain network allowing the use smart contract application for management of IoT devices. Experiment is conducted to show the feasibility of the blockchain based platform. The proposed blockchain based platform is capable of managing several IoT devices connected to the network.

Konstantinos Sgantzos, Ian Grigg

An exemplary paradigm of how an AI can be a disruptive technological paragon via the utilization of blockchain comes straight from the world of deep learning. Data scientists have long struggled to maintain the quality of a dataset for machine learning by an AI entity. Datasets can be very expensive to purchase, as, depending on both the proper selection of the elements and the homogeneity of the data contained within, constructing and maintaining the integrity of a dataset is difficult. Blockchain as a highly secure storage medium presents a technological quantum leap in maintaining data integrity. Furthermore, blockchain’s immutability constructs a fruitful environment for creating high quality, permanent and growing datasets for deep learning. The combination of AI and blockchain could impact fields like Internet of things (IoT), identity, financial markets, civil governance, smart cities, small communities, supply chains, personalized medicine and other fields, and thereby deliver benefits to many people.

Fengkie Junis, Faisal Malik Widya Prasetya, Farouq Ibrahim Lubay, Anny Kartika Sari

Blockchain-based smart contract has become a growing field in the blockchain technology. What was once a technology used to solve digital transaction issues turns out to have some wider usage, including smart contract. The development of smart contract can be traced from the numerous platforms facilitating it, however the issue on how well each platform works as oppose to each other has yet been fully explored. The usage of smart contract can be seen from the applications that are built on top of the smart contract platform, such as the tokenization of real world to virtual world assets. However smart contract contains several issues concerning security and codifying which could be solved by various tools that are proposed by existing research. This paper aims to revisit the blockchain-based smart contract technology in order to understand and discuss the research gaps gathered from existing research and to provide guidance for future research.

Pieter Hartel, Mark van Staalduinen

The Ethereum blockchain is essentially a globally replicated public database.\nPrograms called smart contracts can access this database. Over 10 million smart\ncontracts have been deployed on the Ethereum blockchain. Executing a method of\na smart contract generates a transaction that is also stored on the blockchain.\nThere are over 1 billion Ethereum transactions to date. Smart contracts that\nare transparent about their function are more successful than opaque contracts.\nWe have therefore developed a tool (ContractVis) to explore the transparency of\nsmart contracts. The tool generates a replay script for the historic\ntransactions of a smart contract. The script executes the transactions with the\nsame arguments as recorded on the blockchain, but in a minimal test\nenvironment. Running a replay script provides insights into the contract, and\ninsights into the blockchain explorer that was used to retrieve the contract\nand its history. We provide five concrete recommendations for blockchain\nexplorers like Etherscan to improve the transparency of smart contracts.\n

Yuhang Yao, Xiaoqin Zeng, Tianyue Cao, Luoyi Fu · 5 authors

Due to little attention given to anonymous protection against eavesdropping attacks in Bitcoin network, this paper initiatively proposes a solution to Bitcoin anonymization based on network structure. We first present a general adversarial network model for formulizing deanonymization attack, then present a novel propagation method APRP(Adaptive PageRank Propagation) that adopts PageRank as propagation delay factor and constantly adjusts PR-value of nodes to adapt to network dynamics. Experiments on both simulated and real Bitcoin networks confirm the superiority of APRP in terms of 20-50% performance enhancement under various deanonymization attacks.

Eugenia Politou, Fran Casino, Efthimios Alepis, Constantinos Patsakis

Abstract—Blockchain’s evolution during the past decade is astonishing: from bitcoin to over 2.000 altcoins, and from decentralised electronic payments to transactions programmable by smart contracts and complex tokens governed bydecentralised organisations. While the new generation of blockchain appli- cations is still evolving, blockchain’s technical characteristics are also advancing. Yet, immutability, a hitherto indisputable property according to which blockchain data cannot be edited nor deleted, remains the cornerstone of blockchain’s security. Nevertheless, blockchain’s immutability is being called into ques- tion lately in the light of the new erasing requirements imposed by the GDPR’s “Right to be Forgotten (RtbF)” provision. As the RtbF obliges blockchain data to be editable in order restricted content redactions, modifications or deletions to be applied when requested, blockchains compliance with the regulation is indeed challenging, if not impracticable. Towards resolving this contradiction, various methods and techniques for mutable blockchains have been proposed in an effort to satisfy regulatory erasing requirements while preserving blockchains’ security. To this end, this work aims to provide a comprehensive review on the state-of-the-art research approaches, technical workarounds and advanced cryptographic techniques that have been put forward to resolve this conflict and to discuss their potentials, constraints and limitations when applied in the wild to either permissioned or permissionless blockchains. Index Terms—Blockchain, immutability, Right to be forgotten, GDPR

Bo Zhao, Liming Fang, Hanyi Zhang, Chunpeng Ge · 7 authors

With the development of information technology, films, music, and other publications are inclined to be distributed in digitalized form. However, the low cost of data replication and dissemination leads to digital rights problems and brings huge economic losses. Up to now, existing digital rights management (DRM) schemes have been powerless to deter attempts of infringing digital rights and recover losses of copyright holders. This paper presents a YODA-based digital watermark management system (Y-DWMS), adopting non-repudiation of smart contract and blockchain, to implement a DRM mechanism to infinitely amplify the cost of infringement and recover losses copyright holders suffered once the infringement is reported. We adopt game analysis to prove that in Y-DWMS, the decision of non-infringement always dominates rational users, so as to fundamentally eradicate the infringement of digital rights, which current mainstream DRM schemes cannot reach.

Xingxiong Zhu, Tao Fan

The signing of electronic contracts and the certification of important documents are realized by utilizing blockchain, identity-based cryptography and electronic signature technology. Blockchain technology can realize the data distributed ledgers through the entire system nodes, the whole processes, and the entire transactions. Identity-based cryptography and electronic signature technology can achieve data integrity, privacy, and nonrepudiation. All data is shared by all participating nodes, the information in the cyberspace is more transparent, and the behavior is more traceable. A complete and compliant contract signing process and data certification is achieved.

Mehmet Aydar, Salih Cemil Cetin, Serkan Ayvaz, Betul Aygun

The disruptive technology of blockchain can deliver secure solutions without the need for a central authority. In blockchain protocols, assets that belong to a participant are controlled through the private key of an asymmetric key pair that is owned by the participant. Although, this lets blockchain network participants to have sovereignty on their assets, it comes with the responsibility of managing their own keys. Currently, there exists two major bottlenecks in managing keys; $a)$ users don't have an efficient and secure way to store their keys, $b)$ no efficient recovery mechanism exists in case the keys are lost. In this study, we propose secure methods to efficiently store and recover keys. For the first, we introduce an efficient encryption mechanism to securely encrypt and decrypt the private key using the owner's biometric signature. For the later, we introduce an efficient recovery mechanism using biometrics and secret sharing scheme. By applying the proposed key encryption and recovery mechanism, asset owners are able to securely store their keys on their devices and recover the keys in case they are lost.

Xun Yi, Kwok‐Yan Lam

In this paper, we consider a scenario where a bitcoin liquidity provider sells bitcoins to clients. When a client pays for a bitcoin online, the provider is able to link the client's payment information to the bitcoin sold to that client. To address the privacy concerns of clients, we require that the bitcoin provider cannot tell the relationship between the real identities of clients and the sold bitcoins in the blockchain. This requirement can be effectively achieved by using blind signatures. However, existing blind signature schemes are incompatible with the Elliptic Curve Digital Signature Algorithm (ECDSA) which is used by most of the existing bitcoin protocol, thus cannot be applied directly in Bitcoin. In this paper, we propose a new blind signature scheme that allows generating a blind signature compatible with the standard ECDSA. Afterwards, we make use of the new scheme to achieve bitcoin transaction anonymity. The new scheme is built on a variant of the Paillier cryptosystem and its homomorphic properties. As long as the modified Paillier cryptosystem is semantically secure, the new blind signature scheme has blindness and unforgeability.

Riham AlTawy, Guang Gong

Abstract A major line of research on blockchains is geared towards enhancing the privacy of transactions through anonymity using generic non-interactive proofs. However, there is a good cluster of application scenarios where complete anonymity is not desirable and accountability is in fact required. In this work, we utilize non-interactive proofs of knowledge of elliptic curve discrete logarithms to present membership and verifiable encryption proof, which offers plausible anonymity when combined with the regular signing process of the blockchain transactions. The proof system requires no trusted setup, both its communication and computation complexities are linear in the number of set members, and its security relies on the discrete logarithm assumption. As a use-case for this scenario, we present Mesh which is a blockchain-based framework for supply chain management using RFIDs. Finally, the confidentiality of the transacted information is realized using a lightweight key chaining mechanism implemented on RFIDs. We formally define and prove the main security features of the protocol, and report on experiments for evaluating the performance of the modified transactions for this system.

Alem Fitwi, Yu Chen, Sencun Zhu

Witnessing the increasingly pervasive deployment of security video surveillance systems(VSS), more and more individuals have become concerned with the issues of privacy violations. While the majority of the public have a favorable view of surveillance in terms of crime deterrence, individuals do not accept the invasive monitoring of their private life. To date, however, there is not a lightweight and secure privacy-preserving solution for video surveillance systems. The recent success of blockchain (BC) technologies and their applications in the Internet of Things (IoT) shed a light on this challenging issue. In this paper, we propose a Lightweight, Blockchain-based Privacy protection (Lib-Pri) scheme for surveillance cameras at the edge. It enables the VSS to perform surveillance without compromising the privacy of people captured in the videos. The Lib-Pri system transforms the deployed VSS into a system that functions as a federated blockchain network capable of carrying out integrity checking, blurring keys management, feature sharing, and video access sanctioning. The policy-based enforcement of privacy measures is carried out at the edge devices for real-time video analytics without cluttering the network.

Yatin Trivedi

Let’s put aside the question whether Blockchain is a real technology or a passing fad – a hype. The ups and downs of your fortunes in Bitcoin and similar cryptocurrencies in the last couple of years may have clouded your views. Short-term or long-term success, or failure, of cryptocurrencies may depend on the success, or failure, of Blockchain, but it is important to recognize that Blockchain and the Distributed Ledger Technology (DLT) have far greater uses in wide-ranging applications. One such use of Blockchain is as a key enabling technology of 5G applications. Prof. Chaudhry and Dr. Asad present their research to propose a Blockchain-based Network Slice and Resource Brokerage system to build an open, transparent, and fair 5G ecosystem. They explain the challenges of addressing the massive cooperation required among 5G devices and potential solutions using Blockchain.

Sebastian Henningsen, Daniel Teunis, Martin Florian, Björn Scheuermann

Ethereum is a decentralized Blockchain system that supports the execution of Turing-complete smart contracts. Although the security of the Ethereum ecosystem has been studied in the past, the network layer has been mostly neglected. We show that Go Ethereum (Geth), the most widely used Ethereum implementation, is vulnerable to eclipse attacks, effectively circumventing recently introduced (Geth v1.8.0) security enhancements. We responsibly disclosed the vulnerability to core Ethereum developers; the corresponding countermeasures to our attack where incorporated into the v1.9.0 release of Geth. Our false friends attack exploits the Kademlia-inspired peer discovery logic used by Geth and enables a low-resource eclipsing of long-running, remote victim nodes. An adversary only needs two hosts in distinct /24 subnets to launch the eclipse, which can then be leveraged to filter the victim's view of the Blockchain. We discuss fundamental properties of Geth's node discovery logic that enable the false friends attack, as well as proposed and implemented countermeasures.