Ikram Ud Din, Kamran Ahmad Awan, Ahmad Almogren, Joel J. P. C. Rodrigues
Summary This manuscript provides an inâdepth exploration of metaverses, charting their historical development, technological foundations, and potential multifarious applications. It critically assesses the prevailing challenges and explores potential pathways for the evolution of these expansive, virtual environments. In shedding light on the wideâranging implications of metaverses, it navigates societal, cultural, regulatory, and economic landscapes. It further elucidates the symbiosis between the Internet of Things (IoT) and metaverses, presenting empirical evidence derived from purposeâbuilt IoT frameworks for metaverse applications. A series of experiments were conducted to affirm the hypothesis that the integration of IoT into metaverse utilities, including advanced concepts such as smart buildings, the intricate task of power grid management, and the precisionâcentric domain of agriculture, can drive significant progress. Quantitative findings provide compelling evidence of marked improvements in energy conservation, costâefficiency, and operational effectiveness arising from the incorporation of IoT into metaverse use cases. With observed mean improvements of 25% in energy conservation, 17% in cost reduction, and an impressive 22% increase in operational efficiency, specifically in the realms of smart building applications and power grid management, this study underscores the pressing need for sustained research and development initiatives in this emerging.
The Internet of Things (IoT) refers to the network of interconnected devices that can communicate and share data over the Internet. The widespread adoption of smart devices within Internet of Things (IoT) networks poses considerable security challenges for their communication. To address these issues, blockchain technology, known for its decentralized and distributed nature, offers potential solutions within consensus-based authentication in IoT networks. This paper presents a novel approach called the local and global layer blockchain model, which aims to enhance security while simplifying implementation. The model leverages the concept of clustering to establish a local-global architecture, with cluster heads assuming responsibility for local authentication and authorization. Implementing a local private blockchain facilitates seamless communication between cluster heads and relevant base stations. This blockchain implementation enhances credibility assurance, strengthens security, and provides an effective network authentication mechanism. Simulation results indicate that the proposed algorithm outperforms previously reported methods. The proposed model achieved an average coverage per node of 0.9, which is superior to baseline models. Additionally, the lightweight blockchain model proposed in this paper demonstrates superior capabilities in achieving balanced network latency and throughput compared to traditional global blockchain approaches.
The widespread adoption of distributed energy resources (DERs) and the progress made in internet of things (IoT) and cloud computing technologies have enabled and facilitated the development of various smart grid applications and services. This study aims to develop and implement a peer-to-peer (P2P) energy trading platform that allows local energy trading between consumers and prosumers within a microgrid which combines IoT and blockchain technologies. The proposed platform comprises an IoT-cloud home energy management system (HEMS) responsible for gathering and storing energy consumption data and incorporates a blockchain framework that ensures secure and transparent energy trading. The proposed IoTâblockchain architecture utilizes a Chainlink oracle network and a private Ethereum blockchain. Through the use of smart contracts, consumers and prosumers can participate in an open auction to trade energy, while the settlement process involves acquiring external energy data from an API through the oracle network. The performance of the platform is evaluated through a testbed scenario using real-world energy data from a real house in Valparaiso, Chile, while storing those measurements in AWS cloud, validating the feasibility of the proposed architecture in enabling local energy trading. This work contributes to the development of energy management systems by providing a real-world implementation of an IoTâblockchain architecture for local energy trading. The integration of these technologies will allow for a more efficient and secure energy trading system that can benefit prosumers, consumers, and utilities.
A tracking system capable of storing high volume data, such as mobility indicators, agent and cargo statuses, is of interest to both companies and consumers. Such a system enables the checking of information, such as the locations visited in a shopping center, the duration of employees' stays in certain parts of an office building or factory, whether a bus stopped at each bus stop on a route, the route of a delivery driver, or whether a security team is performing the specified patrol in a neighborhood. This dissertation aims to investigate the efficiency of identifying the current position of a mobile entity and propose a solution for transmitting, adding, and retrieving information like this. The proposed solution is a framework called ARTIIMoR, which stores data securely, immutably, and transparently using a multilayer Distributed Ledger Technology (DLT) system. Three layers of DLT are used to store location information at different levels of abstraction and aggregation. The system aims to allow companies and consumers to record position and movement information with reliability, scalability, and traceability.
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.
Abstract In a networked microgrid system (NMS), various heterogeneous microgrids are interconnected. A networked microgrid system facilitates a new kind of physical design that provides numerous advantages such as distributed economic optimization, reliability, resiliency, and focusing on distributed generations and customers. Designing the secure and privacyâprotected smart power contract between electricity suppliers and consumers, considered as agents, of different microgrids, is a challenging task in the networkedâ microgrid system. Each microgrid implements a heterogeneous or isomorphic blockchain based platform. The blockchain interoperability, inherently, presents in different blockchains implemented by various microgrids. This paper reviews the interoperability issues and smart contract designs in blockchainâbased systems and proposes new mechanisms to cater blockchain interoperability challenges to facilitate the design of secure and seamless smart contracts among different blockchains of microgrids. A network hub of heterogeneous blockchains of network microgrids has been proposed. A methodology has been developed to transfer tokens between interoperable blockchains. A distributed identityâbased microgrid (DIBM) scheme is incorporated to make the networked microgrid system secure and trustworthy. This paper suggests an effective consensus protocol for crossâchain architecture that improves the tokenization system and smart power contract designs. Asynchronous blockchain based federated learning for peerâtoâpeer smart power exchange has been implemented in learning process of interoperable and heterogeneous blockchain based network hub of microgrid. For simulation purposes, MATLAB and python programming have been used with realâtime data of microgrids.
Summary Small cell networks can fulfill the increasing demandfor the high data rate of wireless applications. Energy efficiency is an important design parameter of the ultra dense small cell network (UDSCN). The sleeping strategy of small base stations (sâBSs) is used to enhance the network's energy efficiency. An efficient sleeping strategy of sâBSs is required while preserving users' quality of service (QoS). The idle sâBSs can be switched to sleep mode. This paper proposes a blockchainâenabled solution for the sleeping strategy of sâBSs. Here, a blockchainâenabled small cell network is created between the sâBSs. The network is decentralized, which eliminates the workload of the macro base station (MBS). The proposed network architecture is enabled as a decentralized network through blockchain. The blockchain provides distributed control over the sâBS operations through a smart contract. Here, smart contracts act as distributed self organizing network features to handle selfâtransactions among small cells for switching off sâBSs in the network. All the software logic required to perform sâBS operations is written in a smart contract using Ethereum. The proposed solution improves energy efficiency and enables the ultra dense small cell network to be decentralized.
Abstract A Blockchain is one distributed ledger system, and keeps the high redundancy of ledger copies to make the assurance of network security. However, the continuously duplicated full copies also impose a tremendous amount of demand on some nodes for data storage. The development of blockchain technologies in the IoT(Internet of Things) application scenario is hampered by the restricted storage capacities of terminal devices used in the IoT edge computing scenario, which makes it difficult to load the full copy with infinite growth. Our paper suggests a collaborative ledger storing model based on Chord Ring to address the issues with lightweight blockchains in data storage. On-chain blocks are split by Chord Ring structure and stored in various node clusters in a decentralized manner, and off-chain blocks at various levels are provided with PoW(Proof of Work) consensus asynchronously and archived centrally to the cloud storage on a regular basis. The theoretical and experimental analysis indicates that this model can reduce the data storage redundancy of blockchains while ensuring the high availability of data and the high decentralization of the network.
Roman-Valentyn Tkachuk, Dragos Ilie, Remi Robert, Victor R. Kebande · 5 authors
Renewable energy sources are becoming increasingly important as a substitute for fossil energy production. However, distributed renewable energy production faces several challenges regarding trading and management, such as inflexible pricing models and inaccurate green consumption information. A decentralized peer-to-peer (P2P) electricity marketplace may address these challenges. It enables prosumers to market their self-produced electricity. However, such a marketplace needs to guarantee that the transactions follow market rules and government regulations, cannot be manipulated, and are consistent with the generated electricity. One of the ways to provide these guarantees is to leverage blockchain technology. This work describes a decentralized blockchain-based P2P energy marketplace addressing privacy, trust, and governance issues. It uses a private permissioned blockchain Hyperledger Fabric (HF) and its smart contracts to perform energy trading settlements. The suggested P2P marketplace includes a particular regulator actor acting as a governmental representative overseeing marketplace operations. In this way, the suggested P2P marketplace can address the governance issues needed in electricity marketplaces. Further, the proposed marketplace ensures actorsâ data privacy by employing HFâs private data collections while preserving the integrity and auditability of all operations. We present an in-depth performance evaluation and provide insights into the security and privacy challenges emerging from such a marketplace. The results demonstrate that partial centralization by the applied regulator does not limit the P2P energy trade settlement execution. Blockchain technology allows for automated marketplace operations enabling better incentives for prosumer electricity production. Finally, the suggested marketplace preserves the userâs privacy when P2P energy trade settlements are conducted.
In recent years, music streaming has emerged as the primary method for users to enjoy their favorite songs. Music Streaming Services (MSS) have risen to become influential entities in the music industry, exemplified by Spotifyâs impressive 406 million monthly active users by the end of 2021. However, many artists express concerns that the current MSS model fails to adequately compensate them for their music, raising questions about fairness. To tackle this issue, this paper proposes the implementation of IOTA-MSS, a Pay-per-Play Music Streaming System that leverages the secure and scalable IOTA distributed ledger technology (DLT). By harnessing the capabilities of IOTAâs DLT, IOTA-MSS offers a platform that enables seamless microtransactions. This innovative system empowers users to play and distribute music in real-time while ensuring that rights holders receive corresponding payments. Through the utilization of IOTAâs DLT, IOTA-MSS addresses the challenges faced by artists, providing a more equitable solution for music compensation. By adopting a Pay-per-Play model, this system aligns artist remuneration with the actual usage and popularity of their music. Furthermore, IOTA-MSS enhances the user experience, offering a secure and efficient platform for music enthusiasts to engage with their favorite tunes.
Open access
Blockchain Technology Applications and Security
Advanced Steganography and Watermarking Techniques
Joachim Neu, Srivatsan Sridhar, Lei Yang, David Tse
Classic BFT consensus protocols guarantee safety and liveness for all clients if fewer than one-third of replicas are faulty. However, in applications such as high-value payments, some clients may want to prioritize safety over liveness. Flexible consensus allows each client to opt for a higher safety resilience, albeit at the expense of reduced liveness resilience. We present the first construction that allows optimal safety--liveness tradeoff for every client simultaneously. This construction is modular and is realized as an add-on applied on top of an existing consensus protocol. The add-on consists of an additional round of voting and permanent locking done by the replicas, to sidestep a sub-optimal quorum-intersection-based constraint present in previous solutions. We adapt our construction to the existing Ethereum protocol to derive optimal flexible confirmation rules that clients can adopt unilaterally without requiring system-wide changes. This is possible because existing Ethereum protocol features can double as the extra voting and locking. We demonstrate an implementation using Ethereum's consensus API.
Lorenzo Gigli, Ivan Zyrianoff, Federico Montori, Cristiano Aguzzi · 6 authors
The Internet of Things (IoT) envisions a global market in which it would be possible to easily get data from IoT devices across the globe. However, the potential of this idea still needs to be unlocked. Centralized architectures fall short due to their lack of transparency and tendency to create silos. On the other hand, blockchain technology enables the creation of distributed and trustworthy systems, but its integration with the IoT is still a matter of research. IoT-based scenarios often employ numerous devices for the same sensing task, which may be heterogeneous and unreliable by purpose. In our vision, IoT applications should rely on data and its quality rather than on single providers. For this purpose, we propose an architecture that enables a decentralized IoT global market in which clients pay for data and device owners are rewarded for providing it. Our solution employs a distributed oracle layer on top of smart contracts powered by a distributed global network of IoT devices. The system supports IoT data source decoupling since the end-user can perform semantic queries bounded to specific locations and data types without specifying the target devices. In addition, it features automatic discovery, interoperability mechanisms, and reputation algorithms for the selection of trustworthy data sources. Our results show that the proposed system is robust and consistently provides quality data, even with multiple malicious data sources.
Blockchain establishes security and trust in mobile ad hoc networks (MANETs). Due to the decentralized and opportunistic communication characteristics of MANETs, hashgraph consensus is more applicable to the MANET-based blockchain. Sharding scales the consensus further through disjoint nodes in multiple shards simultaneously updating ledgers. However, the dynamic addition and deletion of nodes in a shard pose challenges regarding robustness and efficiency. Particularly, the shard is vulnerable to Sybil attacks and targeted attacks, and dishonest gossip reduces the efficiency of hashgraph consensus. Therefore, we proposed a behavior-based sharding hashgraph scheme. First, dishonest behaviors of nodes are recorded in a decentralized blacklist. Gossip information is sent to a reliable neighbor, and gossip information from another reliable neighbor is received. Second, a tree-assisted inter-sharding consensus is proposed to prevent Sybil attacks. The combination of shard recovery and reconfiguration based on node state is devised to prevent targeted attacks. Finally, we conducted the performance evaluation including security analysis and experimental evaluation to reveal the security and efficiency of the proposed scheme.
This paper introduces TeleBTC, a fully decentralized protocol designed to wrap Bitcoin (BTC) on programmable blockchains. The creation of a decentralized wrapped BTC presents challenges due to the non-programmable nature of Bitcoin, making it difficult to custody BTCs in a decentralized way. Existing solutions have addressed this challenge by introducing an external layer of validators who take custody of users' BTCs. However, the security and decentralization of this layer are inferior to the underlying blockchains on which wrapped BTC is built. Moreover, the process of joining or leaving for a validator has become overly complex and expensive. To overcome these limitations, we propose a novel approach that eliminates the need for such an external layer by leveraging the light client bridge protocol. Additionally, we employ economic mechanisms such as incentivization and slashing, resulting in a secure and trust-minimized wrapped BTC solution. With TeleBTC, users can seamlessly transfer their BTC to other blockchains and utilize it within decentralized applications. Furthermore, they can unwrap their TeleBTC and reclaim the native BTC. To address the high costs associated with light client bridges, we present an optimistic approach that minimizes the cost. This approach significantly reduces the operational expenses of running the protocol.
Designing the secure and privacy-protected smart power contract between electricity suppliers and consumers, considered agents, of different microgrids, is a challenging task in the networked- microgrid system. A framework is suggested in which each microgrid implements a heterogeneous or isomorphic blockchain based platform. The blockchain interoperability, inherently, is present in different blockchains implemented by various microgrids. This paper reviews the interoperability issues and smart contract designs in blockchain based systems. The paper proposes new mechanisms to cater blockchain interoperability challenges to facilitate the design of secure and seamless smart contracts among different blockchains of microgrids. A network hub of heterogeneous or isomorphic blockchains of network microgrids has been created. A methodology has been developed to transfer tokens between interoperable blockchains. Distributed identity-based microgrid (DIBM) scheme is incorporated to make the networked microgrid system secure and trustworthy. This paper suggests an effective consensus protocol for cross-chain architecture that improves the tokenization system and smart power contract designs. For simulation purposes, MATLAB and python programming have been used with real-time data of microgrids.
The InterPlanetary File System (IPFS) is currently the largest decentralized storage solution in operation, with thousands of active participants and millions of daily content transfers. IPFS is used as remote data storage for numerous blockchain-based smart contracts, Non-Fungible Tokens (NFT), and decentralized applications. We present a content censorship attack that can be executed with minimal effort and cost, and that prevents the retrieval of any chosen content in the IPFS network. The attack exploits a conceptual issue in a core component of IPFS, the Kademlia Distributed Hash Table (DHT), which is used to resolve content IDs to peer addresses. We provide efficient detection and mitigation mechanisms for this vulnerability. Our mechanisms achieve a 99.6\% detection rate and mitigate 100\% of the detected attacks with minimal signaling and computational overhead. We followed responsible disclosure procedures, and our countermeasures are scheduled for deployment in the future versions of IPFS.
This paper proposes a general and interoperable Web of Things (WoT)-oriented architecture to support a distributed storage application. In particular, the focus is on a distributed ledger service dedicated to machine-to-machine (M2M) transactions occurring in an intelligent ecosystem. For this purpose, the basic functional modules have been characterized and integrated into a comprehensive framework relying on an IOTA approach. Furthermore, a general protocol that is built upon an underlying publish-and-subscribe framework is proposed to support all the application phases. The proposed approach has been validated by a simulation campaign targeting the achievable latency and throughput and, further, by a qualitative analysis of high-level metrics, both pointing out several advantages in terms of interoperability, scalability, and mobility support, together with addressing some constraints affecting service availability and security.
Rongxin Xu, Qiujun Lan, Shiva Raj Pokhrel, Gang Li
The Internet of Things (IoT) and distributed ledger technology (DLT) have significantly changed our daily lives. Due to their distributed operational environment and naturally decentralized applications, the convergence of these two technologies indicates a more lavish arrangement for the future. This article develops a comprehensive survey to investigate and illustrate state-of-the-art DLT for various IoT use cases, from smart homes to autonomous vehicles and smart cities. We develop a novel framework for conducting a systematic and comprehensive review of DLT over the IoT by extending the knowledge graph approach. With relevant insights from this review, we extract innovative and pragmatic techniques to DLT design that enable high-performance, sustainable, and highly scalable IoT systems. Our findings support designing an end-to-end IoT-native DLT architecture for the future that fully coordinates network-assisted functionalities.
Block production in Bitcoin, often referred to as mining, is becoming increasingly industrialized. Many nodes in the network are represented by registered business entities. The concept of Bitcoin as a Service is also pushing the industry to become more customer oriented. Services such as transaction validation, transaction status query or notification, and blockchain data indexing are in high demand among blockchain application providers and users. As service providers, nodes need to distinguish themselves from others and be identifiable. In this article, we introduce an efficient self-established identity system, called Miner ID, to enable nodes to be publicly identifiable. It is based on economic investment and active participation in the blockchain network. Moreover, Miner ID is optional for nodes, and it does not affect the consensus mechanism of the network. We explore use cases including instant transaction confirmation, blockchain attestation, public key infrastructure, and token recovery. Miner ID can also be used for secure communication with applications, services, users and peers.
Blockchains face many challenges in time, among which the ever-growing storage needs for blockchainsâ data. In particular, Ethereum is quickly approaching the 1 TB storage limit for a node, what may significantly reduce the candidates able to run an Ethereum fullnode. In this paper, we propose a new synchronization and storage strategy for Ethereum that takes full advantage of the Distributed Hash Table implemented in all clients but left unused. By digging into the history of Ethereumâs synchronization and storage strategies, we justify why such distribution of storage duties among peers makes much sense today. We implemented our solution in the official Ethereum client Geth and validated its smooth operation on a private Ethereum instance. Our solution can save around 60% of the storage of a node (360 GB) which represents a total of 12 PB of data at the network scale, while being fully backward compatible with current clients.
Voting mechanisms play a crucial role in decentralized governance of blockchain systems. Liquid democracy, also known as delegative voting, allows voters to vote directly or delegate their voting power to others, thereby contributing to the resolution of problems such as low voter turnout. In recent years, liquid democracy has been widely adopted by Delegated-Proof-of-Stake (DPoS) blockchains and implemented successfully on platforms with millions of users. However, little is known regarding the characteristics and actual effectiveness of liquid democracy in decentralized governance. This paper explored for the first time the practical implementation of liquid democracy in DPoS blockchain systems. Using actual data collected from two major DPoS blockchains, EOS and Steem, our study compared and evaluated the participation of different types of users of DPoS blockchain systems in liquid democracy, as well as extracting and analyzing the delegation chains and networks formed during the process of liquid democracy within the systems. We believe that the findings of this paper will contribute to further studies on the design and implementation of liquid democracy and other voting mechanisms in decentralized governance.
In March 2021, we witnessed a surge in Bitcoin price. The cause seemed to be a tweet by Elon Musk. Are other blockchains as sensitive to social media as Bitcoin? And more precisely, could Ethereum's popularity be explained using social media data? This work aims to explore the determinants of Ethereum's popularity. We use both data from Etherscan to retrieve the relevant historic Ethereum factors, and Twitter data. Our sample consists of data ranging from 2015 to 2022. We use Ordinary Least Squares to assess the relationship between these factors (Ethereum characteristics and Twitter data) and Ethereum's popularity. Our findings show that Ethereum's popularity - translated here by the number of daily new addresses - is related to the following elements: the Ether (ETH) price, the transaction fees, and the polarity of tweets related to Ethereum. The results could have multiple practical implications, for both researchers and practitioners. First of all, we believe that it will enable readers to better understand the technology Ethereum and its stake. Secondly, it will help the community to identify pointers for the anticipation or explanation of the popularity of existing or future platforms. And finally, the results could help in understanding the factors facilitating the design of future platforms.