Over the past few years, the Internet of Things (IoT) is one of the most significant technologies ever used, as everything is connected to the Internet. Integrating IoT technologies with the cloud improves the performance, activity, and innovation of such a system. However, one of the major problems which cannot be ignored in such integration is the security of the data that are transferred between the client (IoT) and the server (cloud). Solving that problem leads to the use the of IoT technologies in more critical applications and fields. This paper proposes a new security framework by combining blockchain technology with the AES algorithm. Blockchain technology is used and modified to protect data integrity and generate unique device identification within minimal power consumption and best performance. The AES algorithm is used to improve the data confidentiality when being transmitted to the server. The outcomes demonstrated that the proposed solution improves the security system of the IoT healthcare data and proved its efficiency and power consumption compared to other methods.
With the onset of the COVID-19 pandemic and the succession of its waves, the transmission of this disease and the number of deaths caused by it have been increasing. Despite the various vaccines, the COVID-19 virus is still contagious and dangerous for affected people. One of the remedies to this is precaution, and particularly social distancing. In the same vein, this paper proposes a remote voting system, which has to be secure, anonymous, irreversible, accessible, and simple to use. It therefore allows voters to have the possibility to vote for their candidate without having to perform the operation on site. This system will be used for university elections and particularly for student elections. We propose a platform based on a decentralized system. This system will use two blockchains communicating with each other: the public Ethereum blockchain and the private Quorum blockchain. The private blockchain will be institution-specific. All these blockchains send the necessary data to the public blockchain which manages different data related to the universities and the ministry. This system enables using encrypted data with the SHA-256 algorithm to have both security and information security. Motivated by the high energy consumption of blockchain and by the performance improvements in low-power, a test is performed on a low-power embedded platform Raspberry PI4 showing the possibility to use the Blockchain with limited resources.
Real-time tracking and surveillance of patients' health has become ubiquitous in the healthcare sector as a result of the development of fog, cloud computing, and Internet of Things (IoT) technologies. Medical IoT (MIoT) equipment often transfers health data to a pharmaceutical data center, where it is saved, evaluated, and made available to relevant stakeholders or users. Fog layers have been utilized to increase the scalability and flexibility of IoT-based healthcare services, by providing quick response times and low latency. Our proposed solution focuses on an electronic healthcare system that manages both critical and non-critical patients simultaneously. Fog layer is distributed into two halves: critical fog cluster and non-critical fog cluster. Critical patients are handled at critical fog clusters for quick response, while non-critical patients are handled using blockchain technology at non-critical fog cluster, which protects the privacy of patient health records. The suggested solution requires little modification to the current IoT ecosystem while decrease the response time for critical messages and offloading the cloud infrastructure. Reduced storage requirements for cloud data centers benefit users in addition to saving money on construction and operating expenses. In addition, we examined the proposed work for recall, accuracy, precision, and F-score. The results show that the suggested approach is successful in protecting privacy while retaining standard network settings. Moreover, suggested system and benchmark are evaluated in terms of system response time, drop rate, throughput, fog, and cloud utilization. Evaluated results clearly indicate the performance of proposed system is better than benchmark.
With the growing utility of blockchain technology, the desire for reciprocal interactions among different blockchains is growing. However, most operational blockchain networks currently operate in a standalone setting. This fragmentation in the form of isolated blockchains creates interoperability difficulties, inhibiting the adoption of blockchains in various ecosystems. Interoperability is a key factor in the healthcare domain for sharing EHRs of patients registered in independent blockchain networks. Each blockchain network could have its own rules and regulations, obstructing the exchange of EHRs for improving diagnosis and treatments. Examples include patients being treated by healthcare providers in different countries or regions, or within one country but with a different set of rules per state or emirate. By contrast, a federation of blockchain networks can provide better communication and service to stakeholders in healthcare. Thus, solutions for facilitating inter-blockchain communication in such a blockchain federation are needed. However, this possibility has not been fully explored, and further investigations are still being conducted. Hence, the present study proposes a transaction-based smart contract triggering system for inter-blockchain communication, enabling EHR sharing among independent blockchains. We use local and global smart contracts that will be executed once a transaction is created in the blockchain. Local smart contracts are used for EHR sharing within the blockchain, whereas global smart contracts are used for EHR sharing among independent blockchains. The experimental setup is conducted using the Hyperledger Fabric blockchain platform. Inter-blockchain communication between two independent fabric networks is conducted through a global smart contract using Hyperledger Cactus for EHR sharing in a health federation setup. To the best of our knowledge, our study is the first to implement an inter-blockchain communication model in the healthcare domain.
Home delivery (B2C) experienced rapid growth during the COVID-19 pandemic, especially food delivery. Nonrepudiation is a problem in security and affects delivery. Blockchain technology is a new technology that addresses this issue. This paper proposes preventing nonrepudiation in home delivery through blockchain technology. We also design a data structure and smart contract for distributed application. In addition, we evaluate the performance of the proposed framework in terms of transaction fees and response times. We experimented on the blockchain emulator, stored data in RDBMS, and implemented a client with a mobile application. The data in the smart contract were directly impacted by the gas used and the response time. Primarily, the function processes the large data size and involves high transaction fees and long response times. The gas used accounts for 9061 times of data length, while the response time accounts for 2.84 times of data length. Finally, we propose a security policy for the proposed framework.
BACKGROUND Wearable devices have limited ability to store and process such data. Currently, individual users or data aggregators are unable to monetize or contribute such data to wider analytics use cases. When combined with clinical health data, such data can improve the predictive power of data-driven analytics and can proffer many benefits to improve the quality of care. We propose and provide a marketplace mechanism to make these data available while benefiting data providers. OBJECTIVE We aimed to propose the concept of a decentralized marketplace for patient-generated health data that can improve provenance, data accuracy, security, and privacy. Using a proof-of-concept prototype with an interplanetary file system (IPFS) and Ethereum smart contracts, we aimed to demonstrate decentralized marketplace functionality with the blockchain. We also aimed to illustrate and demonstrate the benefits of such a marketplace. METHODS We used a design science research methodology to define and prototype our decentralized marketplace and used the Ethereum blockchain, solidity smart-contract programming language, the web3.js library, and node.js with the MetaMask application to prototype our system. RESULTS We designed and implemented a prototype of a decentralized health care marketplace catering to health data. We used an IPFS to store data, provide an encryption scheme for the data, and provide smart contracts to communicate with users on the Ethereum blockchain. We met the design goals we set out to accomplish in this study. CONCLUSIONS A decentralized marketplace for trading patient-generated health data can be created using smart-contract technology and IPFS-based data storage. Such a marketplace can improve quality, availability, and provenance and satisfy data privacy, access, auditability, and security needs for such data when compared with centralized systems.
Sanjeev Kumar Dwivedi, Ruhul Amin, L. Jegatha Deborah, Pandi Vijayakumar
The blockchain is a peer-to-peer distributed ledger technology that works on the precept of “write-once-read-only.” In a blockchain, pieces of information are arranged in the form of blocks, and these blocks are linked together using the hash value of previous blocks. The blocks in a blockchain mechanism are appended only, which means that once information is stored in a block and it cannot be changed; no one tampers the block’s content. The traditional electronic medical records (EMRs) based system stores the patients’ information in a local database or server, which provides centralization of information, and traditional EMRs are more centric on the health providers. So, security and sharing of patients’ information are difficult tasks in the traditional EMR system. The blockchain mechanism has the potential to resolve these existing problems. Due to the appended-only-ledger principle and decentralization of blocks between the network participants, blockchain technology is suited to the EMR system. In this article, first, we discuss all the existing EMR systems and discuss their drawbacks. Keeping all the drawbacks in our mind, we propose a blockchain-based medical record system that utilizes clouding technology for storage purposes. Furthermore, we have designed a smart contract and consensus algorithm for our proposed EMR. Our system only uses a permissioned blockchain model so that only verified and authenticated users can generate their data and participate in the data-sharing system.
Gowtham Ramkumar, Kishori Kasat, Raseem Abdul Khader P, Nawal Muhammed P K · 6 authors
Recently, there has been significant growth in the consumption of the most widely diversified Internet of Things (IoT) technological knowledge, and devices, which has resulted in an impact on not only electrical items and the agricultural and food industries (Agri-Food) supply chain networks. This has sparked intense curiosity about the development of information sharing that is reliable, traceable, and transparent, and also increased significant research and advancement efforts. Existing IoT-based trace & authenticity methods for agri-food distribution networks are constructed on top of centralized architectures, which creates the potential for significant issues such as data security, manipulation, and standard points of weakness. A creative and scraping methodological approach to implementing decentralized trust-free networks is represented by blockchain technologies, the decentralized blockchain technologies that underpin cryptocurrencies. The fault tolerance, data integrity, visibility, and complete tracing of saved transactional data, along with cohesive digital information of property resources and independent transactions implementations, are in fact features built into this digitalization. This study introduces Agri-BlockIoT, a completely decentralized blockchain-based traceable platform for managing a global agro-food distribution network that can seamlessly connect IoT systems that produce and consume digital information all along the distribution chain. We implemented a use caseto achieve transparency and traceability. Lastly, we analyzed and contrasted the implementations' capability in terms of delay, CPU, or network utilization.
Arshad Ahmad Dar, Malik Zaib Alam, Adeel Ahmad, Faheem Ahmad Reegu · 5 authors
COVID-19 pandemic caused global epidemic infections, which is one of the most severe infections in human medical history. In the absence of proper medications and vaccines, handling the pandemic has been challenging for governments and major health facilities. Additionally, tracing COVID-19 cases and handling data generated from the pandemic are also extremely challenging. Data privacy access and collection are also a challenge when handling COVID-19 data. Blockchain technology provides various features such as decentralization, anonymity, cryptographic security, smart contracts, and a distributed framework that allows users and entities to handle COVID-19 data better. Since the outbreak has made the moral crisis in the clinical and administrative centers worse than any other that has resulted in the decline in the supply of the exact information, however, it is vital to provide fast and accurate insight into the situation. As a result of all these concerns, this study emphasizes the need for COVID-19 data processing to acquire aspects such as data security, data integrity, real-time data handling, and data management to provide patients with all benefits from which they had been denied owing to misinformation. Hence, the management of COVID-19 data through the use of the blockchain framework is crucial. Therefore, this paper illustrates how blockchain technology can be implemented in the COVID-19 data handling process. The paper also proposes a framework with three main layers: data collection layer; data access and privacy layer; and data storage layer.
Blockchain technology (BCT) can enable distributed collaboration, enhance data sharing, and automate back-end processes for digital twin (DT) decentralized applications (dApps) in the construction industry (CI) 4.0. The aim of this paper was to propose a software architecture and to develop a framework of smart contracts for blockchain-based digital twin (BCDT) dApps throughout the lifecycle of projects in CI 4.0. This paper leveraged the existing literature and action research interviews to identify and validate the critical industry problems, functional requirements (FRs), and non-functional requirements (NFRs) to be addressed by BCDT dApps in CI 4.0. Basic use cases were developed to design a framework of smart contracts for BCDT dApps throughout the lifecycle of projects. The analysis of an online survey was used to identify the key requirements and enablers to propose a software architecture for BCDT applications and to validate the requirements for developing the framework of a smart contract for BCDTs. The findings were: (1) The identification of key problems in CI 4.0 for each BIM/BCDT dimension (3D, 4D, 5D, 6D, 7D, 8D, and contractual (cD)) and the related FRs and NFRs for BCDT applications. Additionally, key use cases were designed to address the problems identified. (2) The proposed BCDT architecture permitted us to narrow gaps in the literature on blockchain-based decentralized digital twins. Moreover, the proposed BCDT architecture and smart-contract framework addressed the main requirements in the literature on BCDTs. (3) The study leveraged the non-fungible token (NFT) standard to develop a framework for smart contracts that addressed the key use cases and the related industry problems and functional requirements that were identified. The study also considered the contractual dimension (cD) as an overarching dimension in relation to the other BCDT dimensions. (4) We also compared the costs of several public blockchains for executing the proposed smart-contract framework throughout the lifecycle of a medium-sized building project. The cost analysis permitted the development of criteria to evaluate the suitability of blockchain networks for BCDT applications in CI 4.0 depending on the principal blockchain networks’ properties (security, decentralization, scalability, and interoperability). Finally, this study resulted in a novel framework that included software architecture, smart-contract use cases, and selection criteria among blockchain networks for BCDT dApps in CI 4.0.
Jofina Jijin, Boon‐Chong Seet, Peter Han Joo Chong
The opportunistic fog radio access network (OF-RAN) expands its offloading computation capacity on-demand by establishing virtual fog access points (v-FAPs), comprising user devices with idle resources recruited opportunistically to execute the offloaded tasks in a distributed manner. OF-RAN is attractive for providing computation offloading services to resource-limited Internet-of-Things (IoT) devices from vertical industrial applications such as smart transportation, tourism, mobile healthcare, and public safety. However, the current OF-RAN design is lacking a trusted and distributed mechanism for automating its processes such as v-FAP formation and service execution. Motivated by the recent emergence of blockchain, with smart contracts as an enabler of trusted and distributed systems, we propose an automated mechanism for OF-RAN processes using smart contracts. To demonstrate how our smart-contract-based automation for OF-RAN could apply in real life, a federated deep learning (DL) use-case where a resource-limited client offloads the resource-intensive training of its DL model to a v-FAP is implemented and evaluated. The results validate the DL and blockchain performances of the proposed smart-contract-enabled OF-RAN. The appropriate setting of process parameters to meet the often competing requirements is also demonstrated.
Atualmente, existem diversos dispositivos que coletam dados e prestam serviços na Internet. Alguns desses dispositivos colaboram para trocar informacões e usá-las para tomar decisões mais inteligentes em um ambiente chamado Internet das Coisas (IoT). Recentemente, a tecnologia blockchain surgiu como uma possível solução para superar problemas de segurança em IoT. Apesar disso, blockchains tradicionais (como Bitcoin ou Ethereum) nao são adequados para a natureza de capacidade/recursos limitados dos dispositivos IoT. Alem disso, as propostas atuais carecem de uma discussão sobre o comportamento do usuario em diferentes contextos e como ele pode ser adaptado para diferentes algoritmos de consenso. Para superar esses problemas, apresentamos na tese um conjunto de etapas para criar um mecanismo de consenso multinível para diferentes contextos usando uma estrutura blockchain leve chamada appendable-block blockchain. Essa abordagem fornece uma solução que permite usar diferentes configurações ou consensos, de acordo com os requisitos de cada contexto no ambiente IoT. Por fim, a tese mostra que um consenso multinível pode produzir uma alta taxa de transferencia e baixa latência para inserir novas transações em appendable-block blockchains.
IOTA Tangle is a distributed ledger technology (DLT), primarily designed for Internet-of-Things (IoT) networks and applications. IOTA Tangle utilizes a direct acyclic graph (DAG) structure for the ledger, with its protocol offering features attractive to the IoT domain, over most blockchain alternatives, such as feeless transactions, higher achievable transactions per second (TPS), and lower energy consumption. The original IOTA implementation relied on a bootstrap centralized coordinator solution for consensus which limited its degree of decentralization and scalability. This concern, alongside other limitations to its adoption, such as lack of smart contracts, are being addressed with the release of IOTA 2.0. This update brings with it significant changes in order to remove the coordinator and achieve a scalable decentralized solution. To this end, this paper provides a technical overview of the key features of IOTA 2.0 while discussing their relevance and benefits for the wider IoT ecosystem. The paper also provides performance insights and future research directions for IOTA 2.0.
Fahed Alkhabbas, Mohammed Alsadi, Sadi Alawadi, Feras M. Awaysheh · 6 authors
Internet of Things (IoT) systems are complex systems that can manage mission-critical, costly operations or the collection, storage, and processing of sensitive data. Therefore, security represents a primary concern that should be considered when engineering IoT systems. Additionally, several challenges need to be addressed, including the following ones. IoT systems' environments are dynamic and uncertain. For instance, IoT devices can be mobile or might run out of batteries, so they can become suddenly unavailable. To cope with such environments, IoT systems can be engineered as goal-driven and self-adaptive systems. A goal-driven IoT system is composed of a dynamic set of IoT devices and services that temporarily connect and cooperate to achieve a specific goal. Several approaches have been proposed to engineer goal-driven and self-adaptive IoT systems. However, none of the existing approaches enable goal-driven IoT systems to automatically detect security threats and autonomously adapt to mitigate them. Toward bridging these gaps, this paper proposes a distributed architectural Approach for engineering goal-driven IoT Systems that can autonomously SElf-adapt to secuRity Threats in their environments (ASSERT). ASSERT exploits techniques and adopts notions, such as agents, federated learning, feedback loops, and blockchain, for maintaining the systems' security and enhancing the trustworthiness of the adaptations they perform. The results of the experiments that we conducted to validate the approach's feasibility show that it performs and scales well when detecting security threats, performing autonomous security adaptations to mitigate the threats and enabling systems' constituents to learn about security threats in their environments collaboratively.
May Altulyan, Lina Yao, Salil S. Kanhere, Chaoran Huang
Abstract Recommender system for the IoT (RSIoT) has attracted considerable attention. By leveraging emerging technologies such as the Internet of Things (IoT), artificial intelligence, and blockchain, RSIoT improves various indicators of residents' life. However, data integrity threats may affect the accuracy and consistency of the data particularly in the IoT environment where most devices are inherently dynamic and have limited resources that could fail in ensuring the quality of data transmission. Prior work has focused on processing big data and ensuring their integrity by considering cloud storage service as the popular way. In this article, we address integrity of data leveraging blockchain capabilities to ensure the integrity of the critical data. We adapted the Ethereum blockchain to our RCS for ensuring integrity of data during sharing them between doctor and patient without handling their data by third party. We build four smart contracts that enable our system of gaining more advantage of blockchain. We evaluated the performance of our smart contracts in Kovan and Rinkeby test networks. The preliminary results show the feasibility and effectiveness of the proposed solution.
In this paper, the authors have amplified the concept that EHRs need to be patient-centric and patient-driven, that is the patient should be the real owner as well as the manager of his medical records. The authors propose patient-centric multichain healthcare record (PCMHR) that implements health records using smart contracts on ethereum blockchain and also utilizes the multichain framework - Polygon. PCMHR can concurrently implement blockchain functionality while addressing the concerns of interoperability among authorized hospitals and patient health information confidentiality that damages our healthcare system. The authors propose a solution to fully decentralize the current medical healthcare system by storing PCMHR on IPFS (InterPlanetary File System) to resolve the limitation of blockchain-based applications in scalability and high cost. The authors have depicted the cost and time analysis of transactions on the polygon framework to give a clear view of this multichain framework and its advantages over the ethereum blockchain.
A. A. Talha Talukder, Md. Anisul Islam Mahmud, Arbiya Sultana, Tahmid Hasan Pranto · 6 authors
Food delivery systems are gaining popularity recently due to the expansion of internet connectivity and for the increasing availability of devices. The growing popularity of such systems has raised concerns regarding (i) Information security, (ii) Business to business (B2B) deep discounting race, and (iii) Strict policy enforcement. Sensitive personal data and financial information of the users must be safeguarded. Additionally, in pursuit of gaining profit, the restaurants tend to offer deep discounts resulting in a higher volume of orders than usual. Therefore, the restaurants and the delivery persons fail to maintain the delivery time and often impair the food quality. In this paper, we have proposed a blockchain and smart contract-based food delivery system to address these issues. The main goal is to remove commission schemes and decrease service delays caused by a high volume of orders. The protocols have been deployed and tested on the Ethereum test network. The simulation manifests a successful implementation of our desired system; with the payment being controlled by our system. The actors (restaurant, delivery-person or consumer) are bound to be compliant with the policies or penalized otherwise.
Kangning Zheng, Leven J. Zheng, Jeffrey L. Gauthier, Linyu Zhou · 7 authors
Credit data barriers, such as incomplete credit records, false credit information, and low security of credit data, exist in the supply chain financial credit system, rendering it difficult to support the closure of the whole financing chain's credit system. Emerging blockchain technology can help improve credit-reporting ability through greater integrity, decentralization, transparency, security, and reliability. Aiming to address the problem of extensive credit investigation data and privacy protection, we propose a blockchain-based model to realize access control and management of the shared transaction information in the supply chain. Our model adopts a consensus mechanism to solve the problem of large credit investigation data and privacy protection of credit investigation data and realizes access control and management of the shared data chain. In our model, data are stored on the cloud server and shared with the proxy reencryption method. The model's data structure and workflow are designed to facilitate specific applications in supply chain finance. The embedded blockchain technology helps build the open shared reference architecture and establish the entire life cycle of a monitoring mechanism. The existing blockchain consensus mechanism has low security and a large resource consumption; as such, it is particularly important to design a new consensus mechanism to serve the credit investigation system. In this study, blockchain data sharing and traceability can be realized by improving the consensus mechanism, helping to improve the existing credit investigation service system. Our findings help optimize the existing supply chain financial credit system and enhance the efficiency of supply chain financing.
As society advances, so does the total number of vehicles on the road, creating a massive consumer market for automobiles. According to statistics, a major portion of today's traffic difficulties are caused by accidents caused by subpar cars and auto parts. As a result, each country has, over time, enacted equivalent rules and regulations to prevent such tragedies. However, in the face of profit, some people are desperate enough to employ illegal parts and illegally modified cars, and auto fraud is rampant. As a result, we employ the blockchain of the symmetrical Blockchain's digital ledger and smart contract technology to build a decentralized supply chain system that can identify specific parts. In this study, we design and discuss the proposed system framework by user functions and the flow of parts based on blockchain, and we discuss communication protocols that use the symmetry and asymmetry cryptography, algorithms, properties, and security of the mechanism while providing related analysis and comparing the properties and costs of the system with other studies. Overall, the proposed method has the potential to successfully address the issue of automobile fraud.
The increasing number of security breaches in centralized systems provides the necessity to introduce decentralization in more fields. The Blockchain is a widely utilized decentralization technology that is implemented in various industries. Therefore, this technology can be used to protect sensitive services, such as those associated with the configuration changing of information systems. This article proposes a new protocol operating as a decentralization layer over any configuration scheme. It uses smart contracts—programs existing on the Blockchain—to keep track of configuration proposals and authorize new configurations. The configuration change can be proposed at any time. However, only once it is authorized by appropriate parties can it be introduced to the system. The new protocol provides an additional security layer, ensuring that every action is accounted for and authenticated. Furthermore, it enforces that administrators authorize every change. The protocol was designed to be flexible and easily adaptable to scenarios that did not use distributed ledger technology before. It uses the HTTP protocol with the JSON standard for protocol messages to allow easier adoption and transparency. The features of the proposed protocol were analyzed from a security point of view as well as from the financial perspective related to costs of using Blockchain technology. Security analysis shows that the protocol is resilient to the most common security risks that haunt state-of-the-art IT systems. Additionally, the authors proved that this solution could be implemented in both private and public Blockchains. A reference implementation was shared in a public repository. The proposed protocol was also compared with the most similar state-of-the-art work in the academic research highlighting the key differences and improvements.
Internet of Things (IoT)-based Healthcare services, which are becoming more widespread today, continuously generate huge amounts of data which is often called big data. Due to the magnitude and intricacy of the data, it is difficult to find valuable information that can be used for decision-making and prediction. Big data systems take on a significant infrastructure service to better serve the purpose of IoT systems and support critical decision making. On the other hand, privacy preservation, data integrity, and identity verification are essential requirements in healthcare big data service management. To overcome these problems, this article offers a scalable computing system that provides verifiable data access mechanism for IoT-enabled health data analytics in the big data ecosystem. There are two primary sub-architectures in the proposed architecture, namely a big data analytics tracking system and a derived blockchain-based data storage/access system. This approach leverages big data systems and blockchain architecture to analyze, and securely store data from IoT-enabled devices and allow verified access to the stored data. The zero-knowledge protocol is used to ensure that no information is accessible to unauthenticated users alongside avoiding data linkability. The results demonstrate the effectiveness of the our method to solve the problems of big data analytics and privacy issues in healthcare.
Bhaskar B. Gardas, Arash Heidari, Nima Jafari Navimipour, Mehmet Ünal
The broad availability of connected and intelligent devices has increased the demand for Internet of Things (IoT) applications that require more intense data storage and processing. However, cloud-based IoT systems are typically located far from end-users and face several issues, including high cloud server load, slow response times, and a lack of global mobility. Some of these flaws can be addressed with edge computing. In addition, node selection helps avoid common difficulties related to IoT, including network lifespan, allocation of resources, and trust in the acquired data by selecting the correct nodes at a suitable period. On the other hand, the IoT’s interconnection of edge and blockchain technologies gives a fresh perspective on access control framework design. This article provides a novel node selection approach for blockchain-enabled edge IoT that provides a quick and dependable node selection. Moreover, fuzzy logic to approximation logic was used to manage numerical and linguistic data simultaneously. In addition, the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS), a powerful tool for examining Multi-Criteria Decision-Making (MCDM) problems, is used. The suggested fuzzy-based technique employs three input criteria to select the correct IoT node for a given mission in IoT-edge situations. The outcomes of the experiments indicate that the proposed framework enhances the parameters under consideration.
Milan Todorović, Luka Matijević, Dušan Ramljak, Tatjana Davidović · 7 authors
Blockchains (BCs) are distributed database systems, popular for their innovative, unsupervised maintenance process. They use a so-called consensus protocol to prevent inference by any third party of absolute trust. Security, privacy, consistency, and energy consumption have been identified as the main issues involved in BC maintenance. According to the recent literature, some of these issues can be formulated as combinatorial optimization (CO) problems, and this fact motivated us to consider incorporating CO approaches into a BC. In this paper, we propose the new combinatorial optimization consensus protocol (COCP) based on the proof-of-useful-work (PoUW) concept that assumes solving instances of real-life CO problems. Due to the complexity of the underlying CO problems, we have developed various types of heuristic methods, which are utilized in the COCP. Most of these methods are problem-dependent stochastic heuristic or metaheuristic methods. As is the case with the majority of consensus protocols, PoUW exhibits the property of asymmetry. It is difficult to find a solution for the considered CO problem; however, once a solution is found, its verification is straightforward. We present here a BC framework combining the two above-mentioned fields of research: BC and CO. This framework consists of improvements aiming towards developing the COCP of the PoUW type. The main advantage of this consensus protocol is the efficient utilization of computing resources (by exploring them for finding solutions of real-life CO problem instances), and the provision of a broad range of incentives for the various BC participants. We enumerate the potential benefits of the COCP with respect to its practical impacts and savings in power consumption, describing in detail an illustrative example based on part of the real-life BC network. In addition, we identify several challenges that should be resolved in order to implement a useful, secure, and efficient PoUW consensus protocol.