Everyone should have the right to expression and opinion without interference. Nevertheless, Internet censorship is often misused to block freedom of speech. The distributed ledger technology provides a globally shared database that is geographically distributed and that cannot be controlled by a central authority. Blockchain is an emerging technology that enabled distributed ledgers and has recently been employed for building various types of applications. This paper demonstrates a unique application of blockchain technologies to create a platform that supports the freedom of expression. The paper adapts permissionless and public blockchains in order to leverage their advantages of providing an immutable and tamper-proof digital ledger. The study shows the blockchain potential for providing censorship-resistant publication platform. The paper presents and evaluates possible methods for building such system using the Bitcoin and Ethereum blockchain networks. Our results demonstrate that the Ethereum blockchain is much more beneficial for our system as it requires much lower cost than Bitcoin. to use as a platform to allow freedom of speech.
Open access
Blockchain Technology Applications and Security
Internet Traffic Analysis and Secure E-voting
Advanced Steganography and Watermarking Techniques
Amit Dua, Siddharth Sekhar Barpanda, Neeraj Kumar, Sudeep Tanwar
Modern Internet TCP uses Secure Sockets Layers (SSL)/Transport Layer Security (TLS) for secure communication, which relies on Public Key Infrastructure (PKIs) to authenticate public keys. Conventional PKI is done by Certification Authorities (CAs), issuing and storing Digital Certificates, which are public keys of users with the users identity. This leads to centralization of authority with the CAs and the storage of CAs being vulnerable and imposes a security concern. There have been instances in the past where CAs have issued rogue certificates or the CAs have been hacked to issue malicious certificates. Motivated from these facts, in this paper, we propose a method (named as Trustful), which aims to build a decentralized PKI using blockchain. Blockchains provide immutable storage in a decentralized manner and allows us to write smart contracts. Ethereum blockchain can be used to build a web of trust model where users can publish attributes, validate attributes about other users by signing them and creating a trust store of users that they trust. Trustful works on the Web-of-Trust (WoT) model and allows for any entity on the network to verify attributes about any other entity through a trusted network. This provides an alternative to the conventional CA-based identity verification model. The proposed model has been implemented and tested for efficacy and known major security attacks.
Mobile health applications connect to wearable devices with inbuilt sensors to monitor critical human body parameters such as heart rate, pulse rate, body temperatures ,and others. This paper will introduce our system, Health Record Chain HRC, to investigate how to design and implement secure mobile health systems that leverage the smart mobile devices' new authentication and geo-location mechanism. HRC introduces an enhancing framework to ensure the users' security and privacy and conform to the related regulations ( General Data Protection Regulation GDPR, Health Insurance Portability and Accountability Act HIPPA) using blockchain. The immutability of blockchain conflicts with GDPR’ "Right to be forgotten" when the user can delete all of his/her data. This work implements a blockchain system with a mobile application and a web interface to address this conflict by hashing the Electronic health record EHR to Ethereum based blockchain.
The rise of cryptocurrencies like Bitcoin and Ethereum, along with the underlying blockchain technology, is fundamentally transforming the global financial system. This technological advancement offers significant opportunities for innovation but also presents complex legal challenges. The primary issue is the absence of a uniform global regulatory framework, leading to diverse and sometimes conflicting regulatory approaches among different countries. This regulatory inconsistency creates uncertainty for investors and users. Key concerns include the anonymity provided by cryptocurrencies, which raises issues related to money laundering and terrorist financing, as well as consumer protection and the enforceability of smart contracts. Regulatory authorities have begun implementing measures such as "Know Your Customer" (KYC) policies and transaction monitoring to address these issues, yet the effectiveness of these measures is debated, particularly in jurisdictions with lenient regulations. Blockchain’s decentralized nature poses additional challenges for consumer protection, as there is no central authority to reverse fraudulent transactions. Emerging regulations are focusing on ensuring that cryptocurrency platforms adhere to strict cybersecurity standards. Moreover, blockchain technology introduces new questions regarding property rights and the legal status of smart contracts. The technology’s ability to provide a tamper-resistant record system offers potential benefits for various sectors, including finance, healthcare, and entertainment. However, achieving these benefits requires a strategic, market-wide approach and international cooperation to address jurisdictional and regulatory challenges. The studies by Guadamuz and Marsden (2015), Savelyev (2017), Dierksmeier and Seele (2018), Conti et al. (2017), and Morini (2016) highlight these issues and opportunities, offering insights into the legitimacy, regulation, security, privacy, and business applications of cryptocurrencies and blockchain technology. Collaborative efforts are essential to develop a cohesive regulatory framework that balances innovation with protection and integrity.
The Internet of Things, which connects users (devices) from various fields, has attracted great attention of the public nowadays. It is predicted that IoT will play an increasingly important role in people's daily life. The rapid expansion and extensive applications of IoT pose a significant challenge of authentication due to huge amount of IoT devices. Blockchain offers a promising approach for decentralized authentication in IoT networks with its inherent characteristics. To provide an efficient decentralized mutual authentication and privacy protection for IoT users, this paper presents a blockchain based authentication framework for IoT applications. We conduct security analysis and show that the proposed framework achieves sufficient security provision such as identity anonymity, perfect secrecy, traceability, and resistance to common attacks, etc. In addition, the framework is deployed to the Ethereum to verify its efficiency in terms of storage cost, computational and communication overheads.
Blockchain technology has emerged to provide immense security solutions and create trust between the stakeholders. In a multi-application scenario, fair resource allocation is complex and challenging. Various Resource Allocation Schemes (RAS) have been proposed by the researchers across the globe, but these solutions are not sufficient to handle the security, trust, latency, and bandwidth issues in the network, which introduces vulnerabilities in the system. Motivated from the aforementioned issues, this paper proposes Block-RAS, a blockchain-based RAS to manage the demand-supply of resources between the users and resource providing companies (RPC) in a secured and trusted environment. Block-RAS provides a highly reliable, low-latency, and bandwidth optimum communication between users and RPC with embedded 6G network infrastructure. In Block-RAS, the security, trust, and transparency are achieved using ethereum blockchain, whereas the cost-effective and optimum bandwidth utilization is achieved using the Interplanetary File System (IPFS). Finally, the performance evaluation of Block-RAS is done by a comparative analysis of the proposed approach with traditional approaches that are dependent on centralized 5G based schemes where the Block-RAS outperforms in terms of delay, packet-loss, blockchain block-size, scalability, and network bandwidth utilization.
Evaluating Blockchain performance is not an easy task. It is difficult to compare different systems, since the evaluation is often incomprehensible and conducted in different environments with distinct workloads. Only a handful of prior tools were proposed, e.g., BLOCKBENCH and HFBench. Unfortunately, these tools have several limitations. We first identify these limitations. Second, motivated by our observations, we then present a benchmarking tool, Boston Blockchain Benchmarking (BBB). BBB is configurable, extensible, and easy-touse. In particular, BBB can be used to test Blockchain from a networking perspective, a feature that we have not observed in prior tools. Similar to BLOCKBENCH, we focus on the private Blockchain. Concretely, we integrate our tool with Mininet, and provide a simple mechanism to test how network properties (e.g., latency, bandwidth, package loss rate) affect the performance of the chosen Blockchain. We present our preliminary result of evaluating Ethereum. We stress that the architecture of BBB is general, and could be extended to other Blockchain systems. BBB is extremely lightweight and can be used on your laptop to test a small network. Such a feature allows quick evaluation of the Blockchain and speeds up innovation and development.
Collaborative intrusion detection system (CIDS) shares the critical detection-control information across the nodes for improved and coordinated defense. Software-defined network (SDN) introduces the controllers for the networking control, including for the networks spanning across multiple autonomous systems, and therefore provides a prime platform for CIDS application. Although previous research studies have focused on CIDS in SDN, the real-time secure exchange of the detection-relevant information (e.g., the detection signature) remains a critical challenge. In particular, the CIDS research still lacks robust trust management of the SDN controllers and the integrity protection of the collaborative defense information to resist against the insider attacks transmitting untruthful and malicious detection signatures to other participating controllers. In this paper, we propose a blockchain-enabled collaborative intrusion detection in SDN, taking advantage of the blockchain's security properties. Our scheme achieves three important security goals: to establish the trust of the participating controllers by using the permissioned blockchain to register the controller and manage digital certificates, to protect the integrity of the detection signatures against malicious detection signature injection, and to attest the delivery/update of the detection signature to other controllers. Our experiments in CloudLab based on a prototype built on Ethereum, Smart Contract, and IPFS demonstrates that our approach efficiently shares and distributes detection signatures in real-time through the trustworthy distributed platform.
Industrial Symbiosis can evolve from a simple concept to a revolutionary practical approach where prosumer companies produce goods and provide services through automated negotiation of Smart Contracts by means of new technologies like Internet-of-Things (IoTs) and Blockchain in a Peer-to-Peer (P2P) Market. However, a symbiotic scheme of prosumers exchanging utility surpluses and industrial services gives rise to a great challenge: each company will only participate in the market if the motivation of increasing its own profits exists. I n t his work, each prosumer company is represented by a software agent that resorts to previously learned context-aware strategies for defining prior distributions. Then, strategies are adapted to different opponents when negotiating utility contracts by properly accounting for opponents’ preferences (private) and key contextual (public) information. Agents negotiating Smart Contracts can be readily implemented using Distributed Applications (dApps) over Ethereum/Solidity and digital currencies as the Ether.
This paper explores the taxonomies of stable crypto-assets and discusses the standards associated with Ethereum tokens, including how these compare with certain features of the ISO 20022 industry standard. A brief exploration of simple selected credit transfer features shows that ERC standards are sufficiently flexible to be adapted to ISO 20022 requirements.
Transactions (TX) sent and executed by a public Blockchain (BC) need to pay a TX fee. The fee is relative to the resources consumed when including the TX into a block. The sender of the TX pays for the fee in the native currency of the BC used. Such a fee protects the network from Denial-of-Service (DoS) attacks and provides incentives for TXs inclusion. BCs that support Smart Contracts (SC), thus, TXs can execute user-provided code, require a mechanism for fee calculation depending on the resources consumed by the code executed. Ethereum uses an elaborated mechanism compared to Bitcoin, leading to an increase in the attack surface of their SCs. The mechanism that makes the Bitcoin script - a limited version of SCs - more secure is the ability to compute, independent of the BC's state, an upperbound on resources needed to execute this TX. Thus, this work proposes a new approach enabling security benefits by defining an upper-bound on resource usage for general SCs. Furthermore, the approach allows for the payment of fees in any currency and not just the native currency of the BC.
Like most programs, smart contracts offer their functionality via entry points that constitute the interface. Interface standards, e.g. for tokens contracts, foster interoperability. Ethereum is the most prominent platform for smart contracts. The number of contract deployments approaches 30 million, corresponding to roughly 300 000 distinct contract codes. In view of these numbers, it is necessary to develop automated methods for classifying contracts regarding their purpose, if one aims at a qualitative and quantitative understanding of what blockchain applications are used for at large. We approach the task by considering contracts as similar if their interfaces are. We encode interfaces and their interrelationships as graphs and explore several algorithms regarding their ability to find clusters of functionally similar contracts. Our evaluation of the quality of clustering relies on a ground truth of token and wallet contracts identified in earlier work. Our analysis is based on the bytecodes deployed on the main chain of Ethereum up to block 10.5 million, mined on July 21, 2020.
Rahma Mukta, James Martens, Hye-Young Paik, Qinghua Lu · 5 authors
Sharing credentials could raise privacy concerns. For digital credentials to be widely accepted, there is a need for an end-to-end system that provides (i) secure verification of the participant identities and credentials to increase trust, and (ii) a data minimisation mechanism to reduce the risk of oversharing the credential data. This paper proposes CredChain, a blockchain-based Self-Sovereign Identity (SSI) platform architecture that allows secure creation, sharing and verification of credentials. Beyond the verification of identities and credentials, a flexible selective disclosure solution is proposed using redactable signatures. The credentials are managed through a decentralised application/wallet which allows users to store their credential data privately under their full control and re-use as necessary. Our evaluation results show that CredChain architecture is feasible, secure and exhibits the level of performance that is within the expected benchmarks of the well-known blockchain platform, Parity Ethereum.
The last decade has witnessed fast development of blockchain techniques. However, the high cost of storage space and network bandwidth caused by data synchronization prevents many nodes from joining the network, and becomes a bottleneck impeding the development of blockchain. Traditional schemes typically attempt to transfer most of the storage and computation tasks from a light client to a full node. Nevertheless, they remain susceptible to privacy attacks because light clients need to query and retrieve blockchain data. In this paper, we first describe the privacy issues and challenges for Ethereum data retrieval and then propose a privacy-preserving scheme based on private information retrieval (PIR) to secure retrieval of blockchain data. The main idea is to achieve pointer based PIR search by keywords and introduce differential privacy to mitigate PIR's performance barrier. Hence we achieve a tradeoff between privacy and performance. The evaluations on the Ethereum dataset and analysis show that our scheme is both effective and practical in protecting blockchain access privacy.
The application of blockchain has moved beyond cryptocurrencies, to applications such as credentialing and smart contracts. The smart contract allows ones to achieve fair exchange for values without relying on a centralized entity. However, as the smart contract can be automatically executed with token transfers, an attacker can seek to exploit vulnerabilities in smart contracts for illicit profits. Thus, this paper proposes a support vector machine (SVM)-based scanning system for vulnerabilities on smart contracts. Our evaluation on Ethereum demonstrate that we achieve a identification rate of over 90% based on several popular attacks.
There has been wide range of applications involving smart home systems for user comfort and accessibility to essential commodities. Users enjoy featured home services supported by the IoT smart devices. These IoT devices are resource-constrained, incapable of securing themselves and can be easily hacked. Edge computing can provide localized computations and storage which can augment such capacity limitations for IoT devices. Furthermore, blockchain has emerged as technology with capabilities to provide secure access and authentication for IoT devices in decentralized manner. In this paper, we propose an authentication scheme which integrate attribute based access control using smart contracts with ERC-20 Token (Ethereum Request For Comments) and edge computing to construct a secure framework for IoT devices in Smart home system. The edge server provide scalability to the system by offloading heavier computation tasks to edge servers. We present system architecture and design and discuss various aspects related to testing and implementation of the smart contracts. We show that our proposed scheme is secure by thoroughly analysing its security goals with respect to confidentiality, integrity and availability. Finally, we conduct a performance evaluation to demonstrate the feasibility and efficiency of the proposed scheme.
Bruno Machado Agostinho, Fellipe Bratti Pasini, Fernanda Oliveira Gomes, Alex Sandro Roschildt Pinto · 5 authors
The interest in blockchain technologies has been growing in the last years. Decentralization, scalability, and data integrity are characteristics that can solve problems in different application fields. However, some issues need to be addressed, aiming to facilitate using these systems. Every day the number of users increases, and the possibility of using multiple cryptocurrencies, with several wallets in each one, also brought an issue: How to manage all these addresses? This work proposes a novel architecture, named Wallet Domain Name System (WDNS), to handle several wallets and contracts in different blockchains. Using the Ethereum network to develop a DNS approach, the WDNS uses smart contracts to store and resolve domains and enable multiple subdomains that are managed by the users. Our work provides an open and free data architecture where any person and system can connect and consume. The initial tests showed an average transaction time of almost 15 seconds and a price of 3.30 USD plus 0.0012 USD per character for the domain requests. Also, the tests showed a fixed cost of 0.71 USD plus 1 USD per each synchronized instruction. Comparing the proposed domain price and the average renewal prices for internet domains makes it possible to ensure our proposal's feasibility.
In this paper, we evaluate and analyze the performance of a local electricity market for energy trading that we implemented on the Ethereum platform. The energy trading is based on a double auction with multiple sellers and multiple buyers, and the matched price and volume are determined by a trade reduction mechanism. We benchmark the performance of Ethereum using a systematic blockchain performance evaluation method, and based on this, we propose and analyze an efficient market operation method. In particular, we relate the limits on the scalability and real-time performance of the market to the throughput and latency of the Ethereum platform. We also identify the minimum resources necessary to operate an Ethereum client.
Abstract: In the contemporary world, Ethereum is a very reliable financial saving among cryptocurrencies. It is also well known as a blockchain platform for creating and launching its own cryptocurrency. The applications run on Ethereum executed by a platform-specific cryptographic token, ether. During 2014, Ethereum had launched a pre-sale for ether, which had received an overwhelming response. Ether is used broadly for two purposes: it is traded as a digital currency exchange like other cryptocurrencies, and it is used inside Ethereum to run applications and even to monetize work. It should be noticed that the smart contract has brought a significant share of the success to Ethereum. The smart contract is a computer programme that independently performs assigned tasks between network participants without the participation of a third trusted party. Smart contracts and their intranet transactions have facilitated the rapid expansion of the Ethereum network. Smart contracts are widely represented on the market, either as electronic transaction payments or as applications for the implementation of logistics supplies, gambling, and other sectors. These transactions are irreversible and fully tracked online. Whereas the electronic records are available in a public distributed ledger and include data about user addresses, whereas the real names are hidden. The article explains the usage of decentralized accounts and their electronic transactions in the Ethereum network. The results are presented through different application sectors. Additionally, a new method for extracting blockchain records through node cluster via IPFS path is implemented in the research.
State-of-the-art work of evaluating smart contract static analysis tools faces a major problem: most test cases (i.e., labeled buggy contracts) are too simple and lack complexity, which makes the evaluation unable to show the real performance of the analysis tools when complex contracts are analyzed. To fill the gap, we propose a novel source code obfuscation approach for Ethereum smart contracts. We use the buggy contracts in the public dataset11https://github.com/smartbugs/smartbugs/tree/master/dataset to evaluate our approach. The evaluation result shows that our approach can effectively increase the complexity of a contract. Besides, we use obfuscated contracts to evaluate the static analysis tools. The evaluation result shows that the performance of most smart contract static analysis tools decreases in different degree when the original contracts are obfuscated.
Abstract This system is designed by using Lolin D32 as the processor dan MPL3115A2 for the sensors. This system is designed to show that devices that based on Internet of Things (IoT) could be secured by using blockchain technology. The blockchain technology is based on Ethereum which will be tested in Ropsten Testnet network. Processor module connects to Internet through WiFi module which is one of the Lolin D32 features. This WiFi module connects to router which is used for designing and testing the system. This system wants to prove that the data which are acquired from sensor module MPL3115A2 (altitude, temperature and pressure) and positioning data could be sign and verify within the processor Lolin D32. Before sending the data, the data will be formatted. Data will be stored in smart contract. The smart contract is an Ethereum program which is written using Solidity language. This smart contract is delployed into Ropsten network. The numbers of testing that have been carried out are 516 times. These testings proved as success. The data which were sent to Ropsten network could be proved that they were recorded successfully. These are done by checking through etherscan.io.
Xuan Luo, Zehua Wang, Wei Cai, Xiuhua Li · 5 authors
Traditional centralized token exchange (CEX) has been suffering from hacking due to the centralized management of users’ tokens. In contrast, decentralized token exchange (DEX) maintains users’ assets by smart contracts in a decentralized manner, but introduces additional overhead in terms of gas fee and transaction confirmation latency. Hybrid decentralized token exchange (HEX) has been proposed to combine the benefits of CEX and DEX. However, existing HEX is criticized for two issues. First, trading transactions are time-consuming and expensive for frequent token traders. Second, excessive simultaneous transactions might cause the pending transaction congestion in the Ethereum network. In this paper, we propose a payment channel based HEX, which extends existing solutions by adding a new payment channel layer to benefit frequent traders and alleviate the pending transaction congestion. Besides, we propose the very first gas-price vs. transaction-confirmation-latency function to guide Ethereum transaction issuers to choose an optimal gas price that minimizes the overall cost. Extensive simulations are conducted to compare the cost in the proposed HEX with that in the conventional HEX. The results demonstrate the effectiveness of our proposed mechanism in terms of reducing gas fees and transaction confirmation latency for frequent traders as well as the pending transaction congestion in Ethereum.
EIP-1559 is a proposal to make several tightly coupled additions to\nEthereum's transaction fee mechanism, including variable-size blocks and a\nburned base fee that rises and falls with demand. This report assesses the\ngame-theoretic strengths and weaknesses of the proposal and explores some\nalternative designs.\n
The study aims to elaborate on the Shari’ah issues regarding cryptocurrencies. The research found that overall Shari’ah challenges in studying this unprecedent issue can be confined to Bitcoin since it is the first cryptocurrency with its own protocol and laws, and the later versions of the cryptocurrency started using the protocol of Bitcoin. Bitcoin was distinguished being the only cryptocurrency that is classified as decentralized, whereas the subsequent versions of the currencies, which were introduced as an alternative to Bitcoin, such as Ethereum, were centralized by their issuer. Also, the tokens are merely representing the assets which were collected through it. The overall Shari'ah issues were summarized in terms of its asset and monetary consideration, impact of price fluctuations, decentralization, anonymity, and the mechanism of mining which PoW (Proof-of-Work) and PoS (Proof-of-Stake). This study has concluded on the Shari’ ah permissibility of the PoW system which is used in Bitcoin, and PoS system which is used in Ethereum. The contract is based on Ju’alah contract. As a principle, the study could not conclude the Shari’ah non-permissibility of exchanging, trading or investing in Bitcoin, and similar cryptocurrencies. These cryptocurrencies are subjected to all the guidelines related to exchange of currencies (sarf) and rulings of Riba buyu’ (sale on credit) and Riba duyun (interest on debt). Also, it will be subjected to monetary Zakat rulings. However, dealing with mining groups, electronic platforms, as well as investing in these currencies through various websites, may contain executing agreements and contracts that contain conditions not compliant to Shari’ah. These agreements should be examined in the light of the provisions of the Islamic law. Also, users should be cautious against falling into the net of fraudsters on the Internet. The research recommends to hold-up investing in these recent currencies because of the rapid volatility and to avoid exposing the wealth to high risk.