Federated Learning (FL) is a promising solution for training using data collected from heterogeneous sources (e.g., mobile devices) while avoiding the transmission of large amounts of raw data and preserving privacy. Current FL approaches operate in an iterative manner by selecting a subset of participants each round, asking them to training using their latest local data over the most recent version of the global model, before collecting these local model updates and aggregating them to form the next iteration of the global model, and so forth until convergence is reached. Unfortunately, existing FL approaches typically select randomly the set of clients to use each round, which can negatively impact the quality of the model trained, as well the training round time due to the straggler problem. Moreover, clients, especially mobile devices with limited resources, should be incentivized to participate as federated learning is essentially a form of crowdsourcing for AI which requires monetization. We argue that integrating blockchain and smart contract technologies into FL can solve the two aforementioned issues. In this paper, we present Block-RACS (Blockchain-based Reputation Aware Client Selection), a mechanism for FL operating in a smart contract which rewards clients for their participation using cryptocurrencies. Block-RACS employs a multidimensional auction mechanism for selecting users based on the compute and network resources offered by each client, as well as the quality of their local data. This auction is realized in a reliable and auditable manner through a smart contract. This allows Block-RACS to measure the relative contribution of each client by calculating a Shapley value and allocating rewards accordingly. Moreover, a blockchain-based reputation mechanism enables audibility and non-repudiation. The security analysis of the system is also presented to check the security vulnerabilities. We have implemented Block-RACS using Solidity and tested on the Ethereum blockchain with various popular datasets. Our results show that Block-RACS outperforms existing baseline schemes by improving accuracy and reducing the number of FL rounds.
Abstract In this letter, we propose the use of a blockchainâbased solution for interâprovider agreements in 6G networks, utilizing smart contracts and Chainlink for monitoring and assessing Service Level Agreements (SLAs), including penalty calculations. We evaluate the proposed solution by deploying it on two public blockchains, Ethereum and Polygon, and find that Polygon provides a costâeffective option for creating interâprovider agreements. This is particularly important for use cases involving numerous transactions. Additionally, Chainlink enables secure and transparent access to offâchain SLA data, and we observe lower transaction latency in Polygon. This suggests that utilizing blockchainâbased solutions such as smart contracts can aid the process of creating interâprovider agreements for leasing and selling resources in 6G networks, with Chainlink oracle providing support for their SLA management. However, factors such as transaction cost and latency need to be considered.
Utilizing blockchain technology for different applications has seen a growing interest in recent years. Academic institutions can consider implementing a student information system (SIS) based on blockchain technology as a promising area. This research paper explores in detail the design and execution aspects of an SIS powered by blockchain technology implemented through ASP.net, C#, Ethereum, Solidity, Ganache and IPFS. The main goal of the proposed system is to tackle important problems concerning data security and accessibility in conventional paper-based or centralized systems. In the proposed SIS system based on blockchain technology there are five distinct user categories: students, stage managers, department managers, college managers, and super administrators. Every user possesses specific functionalities like accessing grades, attendance, subjects, schedules, and profiles. Data integrity and privacy are ensured by the system's design using cryptographic techniques and smart contracts implemented in Solidity. The paper also addresses the technical implementation aspects, involving using ASP.net and C# to develop both the user interface and backend logic. To store decentralized data, the Ethereum blockchain is utilized. The proposed system is evaluated through a series of experiments and performance tests. The assessment of the blockchain-based SIS includes evaluating its efficiency, security, and usability through these tests. The paper highlights the effectiveness of the system in enhancing data security, accessibility, and transparency by providing detailed results and findings.
Since the Merge update upon which Ethereum transitioned to Proof of Stake, it has been touted that it resulted in lower power consumption and increased security. However, even if that is the case, can this state be sustained? In this paper, we focus on the potential impact of competition with other smart contract platforms on the price of Ethereumâs native currency, Ether (ETH), thereby raising questions about the safety and sustainability purportedly brought about by the design of Proof of Stake.
There has been a rise in the demand for blockchain-based smart contract development platforms and language implementations. On the other hand, smart contracts and blockchain applications are generated using non-standard software life cycles, which means that, for example, distributed applications are rarely updated, or bugs are fully addressed by releasing a newer version, leading to security flaws and challenges for users to adopt the technology. Smart contracts have gained significant attention due to their potential to automate and secure various transactions in diverse domains. However, the increasing adoption of smart contracts has also raised concerns about security vulnerabilities and potential risks. In this paper, an overview of smart contracts was discussed in detail. It further distinguished and compared smart contracts security with conventional security regarding security, privacy, communication channel, etc. Different platforms for smart contracts, such as Bitcoin, Ethereum, Counterparty, Stellar, Monax, and Lisk, are also discussed in this paper. Some proposed techniques are used in different areas for handling security threats in smart contracts. In addition, a taxonomy of the smart contracts security application was proposed, which attempts to solve some of the flaws and inadequacies in smart contracts. The study also provides a comprehensive smart contracts security scenario with different techniques. Lastly, the possible attacks posed by threats and vulnerabilities of the smart contracts are provided. The security threats and vulnerabilities addressed in this study are unique to smart contracts.
Smart contracts are self-executing programs that run on blockchain platforms. While smart contracts offer a range of benefits, such as immutability and transparency, they are not immune to vulnerabilities. Malicious actors can exploit smart contract vulnerabilities to execute unintended actions or access sensitive data[1]. One approach to mitigating smart contract vulnerabilities is formal verification. Formal verification is a method of verifying the correctness of software using mathematical techniques. It involves mathematically proving that a program conforms to a set of specifications. Formal verification can help detect and eliminate vulnerabilities in smart contracts before they are deployed on the blockchain. KEVM (K Framework-based EVM) is a framework that allows for formal verification of smart contracts on the Ethereum Virtual Machine (EVM). KEVM uses the K Framework, a formal semantics framework, to specify the behavior of the EVM. With KEVM, smart contract developers can verify the correctness of their contracts before deployment, reducing the risk of vulnerabilities. In this paper, we have studied smart contract vulnerabilities such as Over usage of Gas, Signature Replay attack, and misuse of fallback function. We have also written the formal specification for these vulnerabilities and executed it using KEVM.
BRC-20 (short for Bitcoin Request for Comment 20) token mania was a key storyline in the middle of 2023. Setting it apart from conventional ERC-20 token standards on Ethereum, BRC-20 introduces non-fungibility to Bitcoin through an editable field in each satoshi (0.00000001 Bitcoin, the smallest unit), making them unique. In this paper, we pioneer the exploration of this concept, covering its intricate mechanisms, features, and state-of-the-art applications. By analyzing the multi-dimensional data spanning over months with factual investigations, we conservatively comment that while BRC-20 expands Bitcoin's functionality and applicability, it may still not match Ethereum's abundance of decentralized applications and similar ecosystems.
The Ponzi scheme, an old-fashioned fraud, is now popular on the Ethereum blockchain, causing considerable financial losses to many crypto investors. A few Ponzi detection methods have been proposed in the literature, most of which detect a Ponzi scheme based on its smart contract source code. This contract-code-based approach, while achieving very high accuracy, is not robust because a Ponzi developer can fool a detection model by obfuscating the opcode or inventing a new profit distribution logic that cannot be detected. On the contrary, a transaction-based approach could improve the robustness of detection because transactions, unlike smart contracts, are harder to be manipulated. However, the current transaction-based detection models achieve fairly low accuracy. In this paper, we aim to improve the accuracy of the transaction-based models by employing time-series features, which turn out to be crucial in capturing the life-time behaviour a Ponzi application but were completely overlooked in previous works. We propose a new set of 85 features (22 known account-based and 63 new time-series features), which allows off-the-shelf machine learning algorithms to achieve up to 30% higher F1-scores compared to existing works.
Motivated by proof-of-stake (PoS) blockchains such as Ethereum, two key desiderata have recently been studied for Byzantine-fault tolerant (BFT) state-machine replication (SMR) consensus protocols: Finality means that the protocol retains consistency, as long as less than a certain fraction of validators are malicious, even in partially-synchronous environments that allow for temporary violations of assumed network delay bounds. Accountable safety means that in any case of inconsistency, a certain fraction of validators can be identified to have provably violated the protocol. Earlier works have developed impossibility results and protocol constructions for these properties separately. We show that accountable safety implies finality, thereby unifying earlier results.
Abstract The tokenization of financial assets using blockchain technology is a transformative process that allows for the fractionalization of ownership, thereby creating more accessible investment opportunities compared to traditional financial assets. Recent research has shown that token offerings are subject to moral hazard and fraud. In response to these challenges, we propose a novel token design that is compliant with the legal framework of Switzerland. Our design is characterized by its flexibility and can represent any yield or dividend-bearing asset, such as stocks, bonds, or rental income from real estate. Further enhancing its compatibility, the token conforms to the Ethereum ERC-20 standard, enabling seamless integration with existing decentralized finance solutions. Another contribution of our token design is its innovative approach to dividend distribution. Unlike traditional models that distribute dividends based on ownership at the time of payment, our token design distributes dividends based on holding times. This distinctive approach promotes smoother asset prices between dividend payouts by eliminating the need for compensation payments. Our token prototype represents a potential starting point for future research on leveraging the opportunities of decentralized finance.
Ethereum (ETH) is a popular Layer-1 blockchain platform that has been used to create decentralized applications (dApps) and smart contracts. Ethereum 2.0, or Serenity, is a significant update to the network that intends to address numerous issues with scalability, security, and energy efficiency. The Proof-of-Stake (PoS) consensus method will replace the Proof-of-Work (PoW) mechanism, which is one of the major new features of Ethereum 2.0. Given that PoS doesnât require miners to do intensive mathematical calculations in order to validate transactions, it has the potential to be more energy-efficient than PoW. Additionally, this Ethereum upgrade will also be more secure due to the introduction of a new mechanism called âCasperâ that will ensure that validators are always in agreement on the state of the blockchain. The paper begins by discussing the current issues facing Ethereum, including the limitations of the Proof of Work (PoW) consensus mechanism and the need for more efficient and scalable solutions. In this study, we peered at the major changes introduced by Ethereum 2.0, such as the new consensus method (Proof-of-Stake) and the addition of shard chains (Ethereum 2.0), as well as the associated development timelines, benefits and the community criticism on this upgrade.
Liaqat Ali, M. Imran Azim, Nabin B. Ojha, Jan Peters · 9 authors
The electricity market has increasingly played a significant role in ensuring the smooth operation of the power grid. The latest incarnation of the electricity market follows a bottom-up paradigm, rather than a top-down one, and aims to provide flexibility services to the power grid. The blockchain-based local energy market (LEM) is one such bottom-up market paradigm. It essentially enables consumers and prosumers (those who can generate power locally) within a defined power network topology to trade renewable energy amongst each other in a peer-to-peer (P2P) fashion using blockchain technology. This paper presents the development of such a P2P trading-facilitated LEM and the analysis of the proposed blockchain-based LEM by means of a case study using actual German residential customer data. The performance of the proposed LEM is also compared with that of BAU, in which power is traded via time-of-use (ToU) and feed-in-tariff (FiT) rates. The comparative results demonstrate: (1) the participantsâ bill savings; (2) mitigation of the power gridâs export and import; (3) no/minimal variations in the margins of energy suppliers and system operators; and (4) cost comparison of Ethereum versus Polygon blockchain, thus emphasising the domineering performance of the developed P2P trading-based LEM mechanism.
Tran Viet Khoa, Do Hai Son, Chi-Hieu Nguyen, Dinh Thai Hoang · 11 authors
With the escalating prevalence of malicious activities exploiting vulnerabilities in blockchain systems, there is an urgent requirement for robust attack detection mechanisms. To address this challenge, this paper presents a novel collaborative learning framework designed to detect attacks in blockchain transactions and smart contracts by analyzing transaction features. Our framework exhibits the capability to classify various types of blockchain attacks, including intricate attacks at the machine code level (e.g., injecting malicious codes to withdraw coins from users unlawfully), which typically necessitate significant time and security expertise to detect. To achieve that, the proposed framework incorporates a unique tool that transforms transaction features into visual representations, facilitating efficient analysis and classification of low-level machine codes. Furthermore, we propose an advanced collaborative learning model to enable real-time detection of diverse attack types at distributed mining nodes. Our model can efficiently detect attacks in smart contracts and transactions for blockchain systems without the need to gather all data from mining nodes into a centralized server. In order to evaluate the performance of our proposed framework, we deploy a pilot system based on a private Ethereum network and conduct multiple attack scenarios to generate a novel dataset. To the best of our knowledge, our dataset is the most comprehensive and diverse collection of transactions and smart contracts synthesized in a laboratory for cyberattack detection in blockchain systems. Our framework achieves a detection accuracy of approximately 94% through extensive simulations and 91% in real-time experiments with a throughput of over 2,150 transactions per second.
The concept of blockchain has recently gained a lot of popularity because it can be applied to practically every industry and commercial transaction while maintaining sufficient security measures. A comprehensive solution for safe and transparent transactions is offered by the blockchain-based platform TranKrypto. The platform uses Ethereum as its blockchain network and leverages several technologies, such as React, Solidity, Vite, Tailwind, Node.js, and MongoDB, to create a decentralized network of nodes that work together to maintain the ledger. User identification, smart contracts, an admin panel, and a decentralized ledger are just a few of the platform's features that offer a safe and open method to do business transaction. The objective of this research activity is to provide a detailed overview of TranKrypto, which makes use of the technologies node, react, solidity, vite, tailwind, and MetaMask. Our proposed approach includes an admin panel built with React, MUI, and Redux, a server built with Node.js, and user data stored on MongoDB. Additionally, this endeavour provides users with a service that enables them to test Ethereum transactions using the Goerli Ethereum test net on their computer. Key Words: Blockchain, TranKrypto, MongoDB, Node.js, React, Ethereum, MetaMask
<span>Recently, medical records have been stored and shared locally, which creates a risk of data loss or corruption; these records may be stored and shared through cloud-based central data centers; nonetheless, this strategy has disadvantages, such as the need for significant storage space and the privacy concerns associated with network-wide data sharing. Medical records require increased security and confidentiality, furthermore, these records must be protected when transmitted to and shared with doctors of the same specialization, to solve this problem, blockchain technology was used as a decentralized technology that offers a secure and immutable way to store and protect information. In this paper, a website is designed that uses blockchain technology to save medical records and employs smart contract technology in the ethereum blockchain to govern the creation and display of files and sharing. An interplanetary file system was used to offer a mechanism for the decentralized storage of medical images and reports while maintaining their accessibility on a global scale, it is available only for doctors who have the authority to access them, and the proposed system proved efficient in saving and sharing medical records with high security and less cost.</span>
Blockchains are decentralized and immutable databases that are shared among the nodes of the network. Although blockchains have attracted a great scale of attention in the recent years by disrupting the traditional financial systems, the transaction privacy is still a challenging issue that needs to be addressed and analysed. We propose a Private Token Transfer System (PTTS) for the Ethereum public blockchain in the first part of this paper. For the proposed framework, zero-knowledge based protocol has been designed using Zokrates and integrated into our private token smart contract. With the help of web user interface designed, the end users can interact with the smart contract without any third-party setup. In the second part of the paper, we provide security and privacy analysis including the replay attack and the balance range privacy attack which has been modelled as a network flow problem. It is shown that in case some balance ranges are deliberately leaked out to particular organizations or adversial entities, it is possible to extract meaningful information about the user balances by employing minimum cost flow network algorithms that have polynomial complexity. The experimental study reports the Ethereum gas consumption and proof generation times for the proposed framework. It also reports network solution times and goodness rates for a subset of addresses under the balance range privacy attack with respect to number of addresses, number of transactions and ratio of leaked transfer transaction amounts.
Open access
3 source records
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
The privacy-preserving data aggregation is a critical problem for many applications where multiple parties need to collaborate with each other privately to arrive at certain results. Blockchain, as a database shared across the network, provides an underlying platform on which such aggregations can be carried out with a decentralized manner. Therefore, in this paper, we have proposed a scalable privacy-preserving data aggregation protocol for summation on the Ethereum blockchain by integrating several cryptographic primitives including commitment scheme, asymmetric encryption and zero-knowledge proof along with the hypercube network topology. The protocol consists of four stages as contract deployment, user registration, private submission and proof verification. The analysis of the protocol is made with respect to two main perspectives as security and scalability including computational, communicational and storage overheads. In the paper, the zero-knowledge proof, smart contract and web user interface models for the protocol are provided. We have performed an experimental study in order to identify the required gas costs per individual and per system. The general formulation is provided to characterize the changes in gas costs for the increasing number of users. The zero-knowledge proof generation and verification times are also measured.
E. Suresh Babu, Mekala Srinivasa Rao, Gandharba Swain, A. Kousar Nikhath · 5 authors
Abstract The technological integration of the Internet of Things (IoT)âCloud paradigm has enabled intelligent linkages of things, data, processes, and people for efficient decision making without human intervention. However, it poses various challenges for IoT networks that cannot handle large amounts of operation technology (OT) data due to physical storage shortages, excessive latency, higher transfer costs, a lack of context awareness, impractical resiliency, and so on. As a result, the fog network emerged as a new computing model for providing computing capacity closer to IoT edge devices. The IoTâFogâCloud network, on the other hand, is more vulnerable to multiple security flaws, such as missing key management problems, inappropriate access control, inadequate software update mechanism, insecure configuration files and default passwords, missing communication security, and secure key exchange algorithms over unsecured channels. Therefore, these networks cannot make good security decisions, which are significantly easier to hack than to defend the fogâenabled IoT environment. This paper proposes the cooperative flow for securing edge devices in fogâenabled IoT networks using a permissioned blockchain system (pBCS). The proposed fogâenabled IoT network provides efficient security solutions for key management issues, communication security, and secure key exchange mechanism using a blockchain system. To secure the fogâbased IoT network, we proposed a mechanism for identification and authentication among fog, gateway, and edge nodes that should register with the blockchain network. The fog nodes maintain the blockchain system and hold a shared smart contract for validating edge devices. The participating fog nodes serve as validators and maintain a distributed ledger/blockchain to authenticate and validate the request of the edge nodes. The network services can only be accessed by nodes that have been authenticated against the blockchain system. We implemented the proposed pBCS network using the private Ethereum 2.0 that enables secure deviceâtoâdevice communication and demonstrated performance metrics such as throughput, transaction delay, block creation response time, communication, and computation overhead using stateâofâtheâart techniques. Finally, we conducted a security analysis of the communication network to protect the IoT edge devices from unauthorized malicious nodes without data loss.
The real industry is crucial sector of the world wide financial system, with significant economic, social and environmental implications. However, real estate transactions are often slow, complex and costly and can be prone to fraud errors, which can lead to significant financial losses and legal disputes. This paper proposes the adoption of blockchain technology in real estate cadastral systems as a solution to the challenges encountered in managing property ownership and transactions. We have described the implementation of our prototype called REMS (Real Estate Management System) and we have presented the deployment of smart contracts in Ethereum platform. Based on measurement, benchmarks and other observation of the system, we have evaluated the server usage of the blockchain network and decided whether Blockchain-as-a-Service (BaaS) should be involved or not in our system. The study results demonstrate the successful implementation of a real estate management system (REMS) using blockchain technology and Ethereum's smart contracts. This study is important because it confirms that similar solutions can be implemented in other areas of public administration, where the structure of the work is similar, i.e. where we deal with issuing documents to citizens.
The derivative of token standard of Ethereum blockchain, termed as Non Fungible Token is distinguishable token. These tokens are bound with digital properties that provide them unique identification which helps in fulfilling the aim of distinguishable tokens. These tokens are used as an evidence of ownership for the digital asset, with which they are bound to. And it is with these non fungible tokens that the problem of proving ownership of digital asset is being solved and with this technique, it is with hope that developers are looking forward to solve many more problems of the real world with it, may it be providing tradability solutions for arts, real estate and many other sectors. During the time of writing this, the NFT has shown unpredictable growth in the recent years and this has caused the stimulation of prosperity of DApps(Decentralized Application).With an unpredictable growth and garnering attention worldwide with many mainstream key people investing in it , the NFT is still in developing stage and is still premature. This paper is an attempt to squeeze the NFT developments systematically, so the aspiring developers can have the resource to start with and aid the development process further
Unlike traditional currencies that rely on centralized such as banks or governments, cryptocurrencies have become popular due to its decentralized transactions. Decentralization takes advantage of no requirement for intermediaries, thus reducing transaction fees and processing times. However, investing in cryptocurrencies incurs risks and uncertainties due to price volatility and rapid changes. The fact that prediction of asset prices is complex due to the influence of multiple factors on price movements. This paper studied the technical factor to analyse the short-term returns of Ethereum (ETH) in the periods of 1-10 days. The historical data containing ETH closing price are collected from CoinGecko. The twenty-two indicators are chosen from Momentum, Volatility, and Sentiment factors as candidates to provide valuable insights in market trends. By calculating various indicators based on past closing prices, this study utilizes XGBoost, a powerful boosted decision trees ensemble, to discover patterns in previous trading. The model performance is evaluated using the multi-class AUC-ROC metric, which measures the accuracy of predicting three types of ETH returns: Downtrend, Sideway, and Uptrend. The results show that the models achieve accuracy scores ranging from 0.65 to 0.67. Moreover, the study emphasizes the importance of considering momentum indicators when making investment decisions in Ethereum. Keywordsâcryptocurrency investment, technical factor, Ethereum, XGBoost, machine learning
A Distributed Concensus System (DCS) is a key component for a distributed system, maintaining and consenting over distributed state, as often required in distributed filesystems, cryptocurrencies and other applications. The prevalent mechanism to distribute the information needed to reach consensus in a DCS is through an iterative diffusion with the goal of distributing the (updated) information to at least the majority of DCS participants. Such diffusion is not just costly in maintaining the needed communication relations but also incurs latency in performing the diffusion itself. When looking closer at the goal of achieving the majority rule, however, one may wonder of the lack of multicast being used for achieving the same goal. This paper thus returns to the original intention of how to distribute information to a large set of users and outlines reasons for why multicast has not been widely used thus far. We evaluate the potential gain in doing so, based on an analytical model for the diffusion latency in an iterative diffusion DCS, bounded through empirical studies in an Ethereum system.
Quality management (QM) of additive manufacturing (AM) processes is currently immature in terms of transparency, traceability and security. In particular, quality-relevant documents are not documented and communicated in a traceable and transparent manner, which often leads to quality deficiencies. However, combining AM with blockchain technology can enable a solution that maps the AM value chain digitally, transparently, traceably and securely in a part record. In this work, a quality assurance (QA) concept for the metal-based material extrusion (MEX) process is developed that enables a digital representation of the value chain in the form of an AM part record. The decentralized solution presented in this work uses an architecture consisting of a web application for data acquisition, a decentralized storage solution for storing larger amounts of data, a smart contract for capturing manufacturing events and the Ethereum blockchain for transparent, secure and traceable storage of blockchain data. The AM part record enables traceable and constantly available digital documentation of quality information. The cost-effectiveness of the solution is also shown in a demonstration study. The research results highlight the benefits of a blockchain-based AM part record for digital manufacturing documentation and represent an efficient alternative or extension to existing QM and QA solutions in AM.
Open access
Additive Manufacturing and 3D Printing Technologies
Yerramsetti Sri Uday Kiran Sai Mahesh, Velagapudi Rohith, Vennam Srinivas Reddy, Mrs. B. Ratnamala · 5 authors
The Student Document Management System based on Ethereum Blockchain is a revolutionary project aimed at improving the efficiency and security of document management in educational institutions. With the increasing digitization of student records and the need for reliable verification and authentication mechanisms, this system harnesses the power of blockchain technology to address these challenges. By leveraging the Ethereum blockchain, the system ensures immutability, transparency, and decentralization of student documents. Each document is securely stored on the blockchain, making it tamper-proof and resistant to unauthorized modifications. Smart contracts are used to automate document verification processes, reducing administrative overhead and eliminating the potential for human error. Furthermore, the system provides students with complete control over their documents, allowing them to securely share them with institutions, potential employers, or any relevant parties. The decentralized nature of the blockchain ensures that documents can be accessed from anywhere, at any time, without reliance on a central authority. In summary, the Student Document Management System based on Ethereum Blockchain revolutionizes the way student records are managed, providing enhanced security, efficiency, and transparency.