Mr. Rugved Bahadure, Ms. Riya Khasare, Ms. Sakshi Mahure, Mr. Lakhan Rathod · 6 authors
Abstract: Blockchain has the potential to shake the foundation of e-commerce by enabling exchange relations that are trustless and operate without dedicated intermediaries or even central authorities in the case of permissionless blockchains. Furthermore, the exchange of information and value between companies and consumers might change considerably by enabling unified access to immutable data along the entire supply chain. In this paper, we build a Dapp called Thr3ebay which offers buyers and sellers a secure and transparent platform where transactions are conducted directly between participants, without the need for intermediaries. The platform also provides a userfriendly interface for managing wallets and identities, making it easy for users to buy and sell products on the blockchain. We then examine the potential benefits of building a Web3 e-commerce platform, such as increased security, transparency, and trust, as well as the challenges in terms of scalability, user adoption, and interoperability. Key feature of the Thr3ebay Dapp is its integration with various web3 technologies, including IPFS for decentralized file storage, and the Third-web SDK for user authentication and wallet management. The P2P Decentralized app has also developed a custom front-end for the platform using React, making it easy for users to interact with the marketplace. The purpose of building a Web3 e-commerce app is to create a more secure, transparent, and democratic platform for buying and selling goods and services online, while also providing greater trust and confidence for buyers and sellers
Blockchain technology constitutes a paradigm shift in the way we conceive distributed architectures. A Blockchain system lets us build platforms where data are immutable and tamper-proof, with some constraints on the throughput and the amount of memory required to store the ledger. This paper aims to solve the issue of memory and performance requirements developing a multiple Blockchain architecture that mixes the benefits deriving from a public and a private Blockchain. This kind of approach enables small sensors - with memory and performance constraints - to join the network without worrying about the amount of data to store. The development is proposed following a context-aware approach, to make the architecture scalable and easy to use in different scenarios.
Some of the well-known signature techniques like Winternitz and Lamport are not considered to be very appropriate for the usage of hashing or smart contracts in Blockchains security because of their size O(n2), which is prominently too high. Although in Blockchain, the security concern is on the top priority because of its distributed P2P design still, the security enhancement is required to sign and verify the documents forwarded to the peers, especially in Hyperledger Fabric. Here, this paper presents a new signature technique “Block-Hash” to enhance Blockchain security by using it in smart contracts as well as hashing with size 3Xn bits (n=256, generally for SHA-256 Hashing) and which can score 112 bits security. The proposed signature can be used appropriately for signing a smart contract by the endorser or committer node. Also, it can be used with a hash algorithm in forming a Merkle tree. Apart from the description and implementation of Block-Hash Signature, this paper has covered the analysis of its security and correctness measures with a table for result comparison.
We investigate the recent fee mechanism EIP1559 of the Ethereum network. Whereas previous studies have focused on myopic miners, we here focus on strategic miners in the sense of miners being able to reason about the future blocks. We derive expressions for optimal miner behavior (in terms of setting block sizes) in the case of 2-block foresight and varying degrees of hashing power. Results indicate that a sufficiently large mining pool will have enough hashing power to gain by strategic foresight. We further use a simulation study to examine the impact of both 2-block and 3-block foresight. In particular, the simulation study indicates that for realistic levels of hashing power, mining pools do not gain from being able to reason more than 2 blocks ahead. Moreover, even though the presence of strategic miners increase the variation in block sizes and potentially empty blocks, overall system throughput tend to increase slightly compared to myopic mining.
The Bitcoin system uses a fully replicated data storage mechanism in which each node keeps a full copy of the blockchain. As the number of nodes in the system increases and transactions get more complex, more and more storage space are needed to store block data. The scalability of storage has become a bottleneck, limiting the practical application of blockchain. This paper proposes a node storage scheme, called RESS, to integrate erasure coding technology into the blockchain to encode multiple blocks. Under the proposed block grouping method, nodes can reduce the times of coded block decoding. In addition, the coding scheme based on Raptor codes proposed in this paper has linear coding and decoding complexity. The rateless feature of Raptor code helps to achieve high decentralization and scalability of the Bitcoin network. RESS ensures data availability, efficiency and blockchain robustness based on achieving storage space scalability. Experimental results show that the proposed scheme reduces the storage requirements of nodes by nearly an order of magnitude.
In recent years, Blockchain-based Online Social Media (BOSM) platforms have evolved fast due to the advancement of blockchain technology. BOSM can effectively overcome the problems of traditional social media platforms, such as a single point of trust and insufficient incentives for users, by combining a decentralized governance structure and a cryptocurrency-based incentive model, thereby attracting a large number of users and making it a crucial component of Web3. BOSM allows users to downvote low-quality content and aims to decrease the visibility of low-quality content by sorting and filtering it through downvoting. However, this feature may be maliciously exploited by some users to undermine the fairness of the incentive, reduce the quality of highly visible content, and further reduce users' enthusiasm for content creation and the attractiveness of the platform. In this paper, we study and analyze the downvoting behavior using four years of data collected from Steemit, the largest BOSM platform. We discovered that a significant number of bot accounts were actively downvoting content. In addition, we discovered that roughly 9% of the downvoting activity might be retaliatory. We did not detect any significant instances of downvoting on content for a specific topic. We believe that the findings in this paper will facilitate the future development of user behavior analysis and incentive pattern design in BOSM and Web3.
Bing-Yang Lin, Daria Dziubałtowska, Piotr Macek, Andreas Penzkofer · 5 authors
DAG-based DLTs allow for parallel, asynchronous writing access to a ledger. Consequently, the perception of the most recent blocks may differ considerably between nodes, and the underlying network properties of the P2P layer have a direct impact on the performance of the protocol. Moreover, the stronger inter-dependencies of several core components demand a more complex and complete approach to studying such DLTs. This paper presents an agent-based, open-sourced simulator for large-scale networks that implement the leaderless Tangle 2.0 consensus protocol. Its scope includes modelling the underlying peer-to-peer communication with network topology, package loss, heterogeneous latency, the gossip protocol with reliable broadcast qualities, the underlying DAG-based data structure, and the consensus protocol. The simulator allows us to explore the performance of the protocol in different network environments, as well as different attack scenarios.
Web3, the next generation of the Internet, represents a decentralized and democratized web. Although it has garnered significant public interest and found numerous real-world applications, there is a limited understanding of people's perceptions and experiences with Web3. In this study, we conducted an empirical study to investigate the categories of Web3 application and their popularity, as well as the potential challenges and opportunities within this emerging landscape. Our research was carried out in two phases. In the first phase, we analyzed 200 popular Web3 projects associated with 10 leading Web3 venture capital firms. In the second phase, we collected and examined code-related data from GitHub and market-related data from blockchain browsers (e.g., Etherscan) for these projects. Our analysis revealed that the Web3 ecosystem can be categorized into two groups, i.e., Web3 infrastructure and Web3 applications, with each consisting of several subcategories or subdomains. We also gained insights into the popularity of these Web3 projects at both the code and market levels and pointed out the challenges in the Web3 ecosystem at the system, developer, and user levels, as well as the opportunities it presents. Our findings contribute to a better understanding of Web3 for researchers and developers, promoting further exploration and advancement in this innovative field.
A donation-based system using blockchain technology can provide transparency and accountability in charitable giving, addressing concerns about the misuse of donated funds. The system would allow donors to contribute directly to specific causes or organizations, with each transaction recorded on a public blockchain ledger, ensuring that funds are used as intended. Smart contracts could be used to automate the distribution of funds according to predetermined rules and conditions, reducing administrative overhead and ensuring that funds are distributed fairly. In addition, the use of cryptocurrency could eliminate the need for intermediaries such as banks, reducing transaction fees and increasing the speed of transfers. The system would also allow for real-time tracking of donations and impact, providing donors with greater visibility into how their contributions are being used and the overall effectiveness of the charitable organizations they support. Overall, a blockchain-based donation system has the potential to improve transparency, efficiency, and accountability in charitable giving, ultimately helping to create a more equitable and sustainable world.
Ahmet Kurt, Abdulhadi Sahin, Ricardo Harrilal-Parchment, Kemal Akkaya
Bitcoin is undoubtedly a great alternative to today's existing digital payment systems. Even though Bitcoin's scalability has been debated for a long time, we see that it is no longer a concern thanks to its layer-2 solution Lightning Network (LN). LN has been growing non-stop since its creation and enabled fast, cheap, anonymous, censorship-resistant Bitcoin transactions. However, as known, LN nodes need an active Internet connection to operate securely which may not be always possible. For example, in the aftermath of natural disasters or power outages, users may not have Internet access for a while. Thus, in this paper, we propose LNMesh which enables offline LN payments on top of wireless mesh networks. Users of a neighborhood or a community can establish a wireless mesh network to use it as an infrastructure to enable offline LN payments when they do not have any Internet connection. As such, we first present proof-of-concept implementations where we successfully perform offline LN payments utilizing Bluetooth Low Energy and WiFi. For larger networks with more users where users can also move around, channel assignments in the network need to be made strategically and thus, we propose 1) minimum connected dominating set; and 2) uniform spanning tree based channel assignment approaches. Finally, to test these approaches, we implemented a simulator in Python along with the support of BonnMotion mobility tool. We then extensively tested the performance metrics of large-scale realistic offline LN payments on mobile wireless mesh networks. Our simulation results show that, success rates up to %95 are achievable with the proposed channel assignment approaches when channels have enough liquidity.
Wenrui Zuo, Aravindh Raman, Raúl J. Mondragón, Gareth Tyson
There has been growing interest in the so-called “Web3” movement. This loosely refers to a mix of decentralized technologies, often underpinned by blockchain technologies. Among these, Web3 social media platforms have begun to emerge. These store all social interaction data (e.g., posts) on a public ledger, removing the need for centralized data ownership and management. But this comes at a cost, which some argue is prohibitively expensive. As an exemplar within this growing ecosytem, we explore memo.cash, a microblogging service built on the Bitcoin Cash (BCH) blockchain. We gather data for 24K users, 317K posts, 2.57M user actions, which have facilitated $6.75M worth of transactions. A particularly unique feature is that users must pay BCH tokens for each interaction (e.g., posting, following). We study how this may impact the social makeup of the platform. We therefore study memo.cash as both a social network and a transaction platform.
Blockchain interoperability promotes value delivery, application expansion, and ecological compatibility across heterogeneous blockchain systems. However, the contract framework and virtual machine construction in these systems are significantly different, and crosschaining becomes a challenging issue for system universality and compatibility. Starting from this problem, in this study, we propose VM-Studio, a crosschain smart contract verification and execution scheme to migrate the virtual machines (VMs) from the origin blockchain to the target blockchain. In our scheme, the migrated VMs are loaded as independent components enclosed in containers. We also design a unified system schedule to enable VM-Studio to allocate transactions into different containers. Loaded with origin blockchain VMs, these containers can accordingly solve crosschain transaction execution and smart contract verification. We implement VM-Studio and evaluate the transaction execution performance in the origin environment with multiple blockchains and the container environment. Experiment results demonstrate that VM-Studio achieves broad universality without compromising the execution performance of original blockchain transactions.
Jie Xu, Qingyuan Xie, Sen Peng, Cong Wang · 5 authors
Although existing schemes improve blockchain throughput by allowing concurrent blocks to be appended to the blockchain, little attention has been devoted to adjusting blockchain throughput dynamically and deduplicating transactions between concurrent blocks. In this article, we propose AdaptChain, an adaptive scaling blockchain with transaction deduplication. When the transaction demand of users in the network is high, the blockchain expands to meet the demand; when the transaction demand is low, the blockchain shrinks to save communication and storage costs. Our transaction deduplication mechanism ensures that no duplicate transactions are added to the blockchain, thereby improving bandwidth utilization and achieving higher effective throughput. Besides, we randomly split the mining power of the system to achieve mining power load balancing and resist attacks. We formally analyze the blockchain security and implement the proposed prototype on Amazon EC2. Experimental results show that AdaptChain achieves dynamic and higher effective blockchain throughput.
Lianna Zhao, Andrew Culleny, Müller, Sebastian, Olivia Saay · 5 authors
This paper discusses congestion control and inconsistency problems in DAG-based distributed ledgers and proposes an additional filter to mitigate these issues. Unlike traditional blockchains, DAG-based DLTs use a directed acyclic graph structure to organize transactions, allowing higher scalability and efficiency. However, this also introduces challenges in controlling the rate at which blocks are added to the network and preventing the influence of spam attacks. To address these challenges, we propose a filter to limit the tip pool size and to avoid referencing old blocks. Furthermore, we present experimental results to demonstrate the effectiveness of this filter in reducing the negative impacts of various attacks. Our approach offers a lightweight and efficient solution for managing the flow of blocks in DAG-based DLTs, which can enhance the consistency and reliability of these systems. Index
Kevin Coutinho, NeerajKumari Khairwal, Pornpit Wongthongtham
Blockchain is a revolutionary technology that is constructively transforming many traditional industries, including financial services. Blockchain demonstrates immense potential in bringing substantial benefits to the remittance industry. Although the remittance industry has crossed the mark of USD 600 billion in 2021, remittance cost is still substantially high, around 6% on average, indirectly limiting financial inclusion and promoting de-risking. The involvement of multiple intermediaries in global remittances makes cross-border payments more expensive. Many projects, including Ripple and Stellar, employ blockchain technology to provide alternative infrastructure for cross-border payments. However, the decentralization of blockchain networks in both solutions is debatable. This paper examines the market characteristics impacting remittance cost, a prominent factor driving the evolution of the remittance industry. A truly decentralized blockchain framework viz. LayerOneX, which provides remittance services at a reduced cost, is proposed in this paper. Devices with low computation and memory capacity can act as transaction validators in this solution. A universal wallet across homogeneous and heterogeneous blockchains is proposed to facilitate fast and inexpensive remittance services. Thus, a novel framework for true decentralization of blockchain-based remittance services, resulting in reduced cost and, therefore, better financial inclusion, is proposed in this paper.
Blockchain can effectively deal with the security and trust issues in Internet of Things (IoT) due to its salient features including decentralization, immutability, traceability, openness, and transparency. However, most IoT devices have too limited computing, storage, and bandwidth resources to maintain the complete operation of a blockchain system. To this end, we propose a hierarchical blockchain framework called HLOChain for IoT scenarios. First, according to computing and storage capabilities, the IoT devices are classified into three levels, i.e., high, medium, and low. They are deployed on different layers. In this way, a hierarchical blockchain architecture is designed. Second, we propose a lightweight proof of random (PoR) consensus mechanism to provide low-energy block mining, so that even the medium nodes can participate in the consensus task. Third, in order to reduce the ledger storage overhead, we design a blockchain storage optimization strategy based on the account model. Finally, the security analysis demonstrates that our HLOChain is secure against double-spend attack, Sybil attack, and so on. The experimental evaluation shows that our HLOChain achieves better performance in ledger storage cost, consensus computing cost, throughput, and transaction confirmation latency.
Consensus mechanisms play a critical role in blockchain networks, ensuring that all participants agree on the state of the distributed ledger. However, existing consensus mechanisms have limitations in terms of efficiency, security, and decentralization. In this research paper, we propose a Hybrid Consensus Mechanism (HCM) that combines the advantages of Delegated Proof of Stake (DPoS), Practical Byzantine Fault Tolerance (PBFT), and Proof of Elapsed Time (PoET) to address these limitations. HCM uses a set of trusted validators (delegates) similar to DPoS, who participate in a PBFT-like consensus protocol to reach agreement on the state of the ledger. PoET is used to randomly select the leader for each consensus round, preventing the concentration of power. HCM also introduces a dynamic delegation mechanism and sharding technique to enhance fairness, resilience, and scalability in blockchain networks. We provide detailed technical insights, backed by underlying data, to illustrate the effectiveness of HCM in achieving efficient and secure consensus.
Miguel Pincheira, Elena Donini, Massimo Vecchio, Raffaele Giaffreda
Blockchain is currently a core technology for developing new types of decentralized applications. With the unique properties of blockchain, unique challenges and characteristics are introduced to the system. Among these characteristics, the infrastructure costs and benefits of the system are critical to evaluate the feasibility of any system and have yet to be addressed in the current literature. This work presents a framework for evaluating blockchain applications’ infrastructure costs and benefits. The framework includes a taxonomy to classify the related transactions, a model to evaluate the infrastructure costs and benefits in applications using public or private blockchains, and a methodology to guide the use of the model. The model is based on simple parameters that describe the systems, and the methodology helps to identify and estimate these parameters at any stage of the application life cycle. We quantitatively analyze three real use cases to demonstrate the framework’s merit. The analyses highlight the model’s accuracy by achieving the same results presented in the use cases. Furthermore, the use-case analyses emphasize the framework’s potential to evaluate different scenarios across the entire life cycle of blockchain-based applications.
Currently, digital certificate systems based on blockchain have been extensively developed and adopted. However, most of them do not take into account the certificate quality. To evaluate the credibility of certificates issued by educational institutions, we propose a novel blockchain-based system with credit self-adjustment (BC-CS). In BC-CS, employers can provide feedback according to the performances of their employees (i.e., students) holding different certificates. Based on the feedback, BC-CS automatically adjusts the certificate credits by using our proposed credit self-adjustment algorithm. To verify the feasibility of our proposed system, a decentralized application prototype has been developed on an Ethereum network. Experimental results demonstrate that the proposed system can fully support multi-step accreditation and automatic adjustment for certificate credit.
Michael G. Xevgenis, Dimitrios G. Kogias, Panagiotis Karkazis, Helen C. Leligou
Undoubtedly, we are witnessing a new era of computer networks that aspire to support modern demanding applications by providing the highest Quality of Experience (QoE) to the end user. Next Generations Networks (NGNs) ensure that characteristics such as ultra-low latency, high availability and wide service coverage can be met across the network regardless of the network infrastructure ownership. To accomplish that, beyond the necessary improvements in the radio propagation field, changes have been made in the core network functions which are now characterized as programmable, and software defined. Software Defined Networks (SDNs) and Network Function Virtualization (NFV) are the keystones of the NGNs flexibility. The high expectations of NGNs’ performance and the continuous changes in the network conditions lead to the development of new network management frameworks that add elasticity and dynamicity and minimize human intervention. ETSI (the European Standards Organization) presents the Zero-touch Service Management (ZSM) framework that uses hyped technologies such as Artificial Intelligence (AI) and Machine Learning (ML) to achieve full end-to-end automation of the network services’ management across one or many different domains. Focusing on multi-domain network service management, there are several security issues identified by the standardization team which mostly derive from the lack of trust among network providers. In the present research, we explore the suitability of blockchain technology adoption for facing these security issues. Blockchain technology inherently addresses security in trustless environments such as the infrastructures defined by the ZSM team. Our contribution is three-fold: (a) we define the architecture of a multi-domain network infrastructure that adopts the ZSM approach and integrates blockchain functionality, (b) we explore the adoption of different blockchain and distributed ledger technologies (DLT) approaches to address ZSM security needs and (c) we provide guidelines to prospective solution designers/implementers on the detailed requirements that this solution has to meet to maximize the offered value.
Closed-circuit television (CCTV) cameras and black boxes are indispensable for road safety and accident management. Visible highway surveillance cameras can promote safe driving habits while discouraging moving violations. According to CCTV laws, footage captured by roadside cameras must be securely stored, and authorized persons can access it. Footages collected by CCTV and Blackbox are usually saved to the camera’s microSD card, the cloud, or hard drives locally but there are concerns about security and data integrity. These issues may be addressed by blockchain technology. The cost of storing data on the blockchain, on the other hand, is prohibitively expensive. We can have decentralized and cost-effective storage with the interplanetary file system (IPFS) project. It is a file-sharing protocol that stores and distributes data in a distributed file system. We propose a decentralized IPFS and blockchain-based application for distributed file storage. It is possible to upload various types of files into our decentralized application (DApp), and hashes of the uploaded files are permanently saved on the Ethereum blockchain with the help of smart contracts. Because it cannot be removed, it is immutable. By clicking on the file description, we can also view the file. DApp also includes a keyword search feature to assist us in quickly locating sensitive information. We used Ethers.js’ smart contract event listener and contract.queryFilter to filter and read data from the blockchain. The smart contract events are then written to a text file for our DApp’s keyword search functionality. Our experiment demonstrates that our DApp is resilient to system failure while preserving the transparency and integrity of data due to the immutability of blockchain.
Joāo Otávio Chervinski, Diego Kreutz, Xiwei Xu, Jiangshan Yu
With the increasing demand for communication between blockchains, improving the performance of cross-chain communication protocols becomes an emerging challenge. We take a first step towards analyzing the limitations of cross-chain communication protocols by comprehensively evaluating Cosmos Network's Inter-Blockchain Communication Protocol. To achieve our goal we introduce a novel framework to guide empirical evaluations of cross-chain communication protocols. We implement an instance of our framework as a tool to evaluate the IBC protocol. Our findings highlight several challenges, such as high transaction confirmation latency, bottlenecks in the blockchain's RPC implementation and concurrency issues that hinder the scalability of the cross-chain message relayer. We also demonstrate how to reduce the time required to complete cross-chain transfers by up to 70% when submitting large amounts of transfers. Finally, we discuss challenges faced during deployment with the objective of contributing to the development and advancement of cross-chain communication.