Dimitris Geneiatakis, Yannis Soupionis, Gary Steri, Ioannis Kounelis · 6 authors
With the continuous development of distributed ledger and blockchain technologies, new use cases apart from cryptocurrencies have come into the spotlight. In this article, we evaluate whether an e-government service could be a suitable candidate for a blockchain transformation. We selected as a reference test system an existing cross-border e-government service that is used for supporting goods exchanges across the European Union. We show how such an indicative paradigm can be transformed into a blockchain system. In order to do so, we deployed it in an emulated architecture for evaluating its performance under various realistic conditions. Our results show that the deployed system is able to meet the requirements, both in terms of throughput and transaction speed. Moreover, it shows clear advantages in terms of usability and synchronization between all entities.
Shengjing Sun, Xiaochen Zheng, Javier Villalba-Díez, Joaquín Ordieres‐Meré
Information-intensive transformation is vital to realize the Industry 4.0 paradigm, where processes, systems, and people are in a connected environment. Current factories must combine different sources of knowledge with different technological layers. Taking into account data interconnection and information transparency, it is necessary to enhance the existing frameworks. This paper proposes an extension to an existing framework, which enables access to knowledge about the different data sources available, including data from operators. To develop the interoperability principle, a specific proposal to provide a (public and encrypted) data management solution to ensure information transparency is presented, which enables semantic data treatment and provides an appropriate context to allow data fusion. This proposal is designed also considering the Privacy by Design option. As a proof of application case, an implementation was carried out regarding the logistics of the delivery of industrial components in the construction sector, where different stakeholders may benefit from shared knowledge under the proposed architecture.
Ouns Bouachir, Moayad Aloqaily, Lewis Tseng, Azzedine Boukerche
Blockchain has revolutionized how transactions are conducted by ensuring secure and auditable peer-to-peer coordination. This is due to both the development of decentralization, and the promotion of trust among peers. Blockchain and fog computing are currently being evaluated as potential support for software and a wide spectrum of applications, ranging from banking practices and digital transactions to cyber-physical systems. These systems are designed to work in highly complex, sometimes even adversarial, environments, and to synchronize heterogeneous machines and manufacturing facilities in cyber computational space, and address critical challenges such as computational complexity, security, trust, and data management. Coupling blockchain with fog computing technologies has the potential to identify and overcome these issues. Thus, this paper presents the knowledge of blockchain and fog computing required to improve cyber-physical systems in terms of quality-of-service, data storage, computing and security.
Francesco Girardi, Gaetano De Gennaro, Lucio Colizzi, Vito Nicola Convertini
New types of patient health records aim to help physicians shift from a medical practice, often based on their personal experience, towards one of evidence based medicine, thus improving the communication among patients and care providers and increasing the availability of personal medical information. These new records, allowing patients and care providers to share medical data and clinical information, and access them whenever they need, can be considered enabling Ambient Assisted Living technologies. Furthermore, new personal disease monitoring tools support specialists in their tasks, as an example allowing acquisition, transmission and analysis of medical images. The growing interest around these new technologies poses serious questions regarding data integrity and transaction security. The huge amount of sensitive data stored in these new records surely attracts the interest of malicious hackers, therefore it is necessary to guarantee the integrity and the maximum security of servers and transactions. Blockchain technology can be an important turning point in the development of personal health records. This paper discusses some issues regarding the management and protection of health data exchanged through new medical or diagnostic devices.
Open access
Blockchain Technology Applications and Security
IoT and Edge/Fog Computing
Artificial Intelligence in Healthcare and Education
Due to the rapid development of the internet of Things (ioT), a massive number of devices are connected to the internet. For these distributed devices in ioT networks, how to ensure their security and privacy becomes a significant challenge. Blockchain technology provides a promising solution to protect the data integrity, provenance, privacy, and consistency for ioT networks. in blockchains, communication is a prerequisite for participants, which are distributed in the system, to reach consensus. However, in ioT networks, most of the devices communicate through wireless links, which are not always reliable. Hence, the communication reliability of ioT devices influences the system security. in this article, we rethink the roles of communication and computing in blockchains by accounting for communication reliability. We analyze the trade-off between communication reliability and computing power in blockchain security, and present a lower bound to the computing power that is needed to conduct an attack with a given communication reliability. Simulation results show that adversarial nodes can succeed in tampering with a block with less computing power by hindering the propagation of blocks from other nodes.
Srđan Vujičić, Nermin Hasanspahić, Maro Car, Leo Čampara
In recent years, many industries have adopted technology and digital systems to automate, expedite and secure specific processes. Stakeholders in maritime transport continue to exchange physical documents in order to conduct business. The monitoring of supply chain goods, communication among employees, environmental sustainability and longevity control, along with time framing, all create challenges to many industries. Everyday onboard work, such as cargo operations, navigation and various types of inspections in shipping, still requires paper documents and logs that need to be signed (and stamped). The conversion of traditional paper contracts into smart contracts, which can be digitalized and read through automation, provides a new wave of collaboration between eco systems across the shipping industry. Various data collected and stored on board ships could be used for scientific purposes. Distributed ledger technology (DLT) could be used to collect all those data and improve shipping operations by process expediting. It could eliminate the need to fill in various documents and logs and make operations safer and more environmentally friendly. Information about various important procedures onboard ships could be shared among all interested stakeholders. This paper considers the possible application of distributed ledger technology as an aid for the control of overboard discharge of wastewater from commercial ships. The intended outcome is that it could help protect the environment by sending data to relevant stakeholders in real time, thus providing information regarding the best discharge areas. The use of a structured communal data transference would ensure a consistent and accurate way to transmit data to all interested parties, and would eliminate the need to fill in various paper forms and logs. Wastewater overboard discharges would be properly monitored, recorded and measured, as distributed ledger technology would prevent any possibility of illegal actions and falsification of documents, thus ensuring environmental sustainability.
One of the alternatives to proof-of-work (PoW) consensus protocols is proof-of- stake (PoS) protocols, which address its energy and cost related issues. But they suffer from the nothing-at-stake problem; validators (PoS miners) are bound to lose nothing if they support multiple blockchain forks. Tendermint, a PoS protocol, handles this problem by forcing validators to bond their stake and then seizing a cheater’s stake when caught signing multiple competing blocks. The seized stake is then evenly distributed amongst the rest of validators. However, as the number of validators increases, the benefit in finding a cheater compared to the cost of monitoring validators reduces, weakening the system’s defense against the problem. Previous work on TontineCoin addresses this problem by utilizing the concept of tontines. A tontine is an investment scheme in which each participant receives a portion of benefits based on their share. As the number of participants in a tontine decreases, individual benefit increases, which acts as a motivation for participants to eliminate each other. Utilizing this feature in TontineCoin ensures that validators (participants of a tontine) are highly motivated to monitor each other, thus strengthening the system against the nothing-at-stake problem. This project implements a prototype of Tendermint using the Spartan Gold codebase and develops TontineCoin based on it. This implementation is the first implementation of the protocol, and simulates and contrasts five different normal operations in both the Tendermint and TontineCoin models. It also simulates and discusses how a nothing-at-stake attack is handled in TontineCoin compared to Tendermint.
Today, the entire world is facing incredible health and economic challenges due to the rapid spread of the life threatening novel Coronavirus Disease - 2019 (COVID-19). In the prevailing situation when a vaccine is many months away, the way forward seems to be a controlled exit from the lockdown - where, infected/exposed people are strictly quarantined and recovered/unexposed people are allowed to carry on with their day to day business activities. However, appropriate physical distancing norms will have to be strictly followed for such relaxations. Therefore, mechanisms are required that will assist people in following the social and physical distancing norms in public places. In this paper, we propose an anonymity preserving blockchain based framework that allows people, through use of their smart phones and other communication devices, to protect themselves from infections as they conduct their daily business activities.
Edge computing draws a lot of recent research interests because of the performance improvement by offloading many workloads from the remote data center to nearby edge nodes. Nonetheless, one open challenge of this emerging paradigm lies in the potential security issues on edge nodes and end devices, e.g., sensors and controllers. This paper proposes a cooperative protocol, namely DEAN, across edge nodes to prevent data manipulation, and to allow fair data sharing with quick recovery under resource constraints of limited storage, computing, and network capacity. Specifically, DEAN leverages a parallel mechanism equipped with three independent core components, effectively achieving low resource consumption while allowing secured parallel block processing on edge nodes. We have implemented a system prototype based on DEAN and experimentally verified its effectiveness with a comparison with three popular blockchain implementations: Ethereum, Parity, and Hyperledger Fabric. Experimental results show that the system prototype exhibits high resilience to arbitrary failures: the percentile of trusty nodes is much higher than the required 50\% in most cases. Performance-wise, DEAN-based blockchain implementation outperforms the state-of-the-art blockchain systems with up to $25\times$ higher throughput and $18\times$ lower latency on 1,000 nodes.
Andrew Cullen, Pietro Ferraro, William H. Sanders, Luigi Vigneri · 5 authors
In the Internet of Things (IoT) domain, devices need a platform to transact\nseamlessly without a trusted intermediary. Although Distributed Ledger\nTechnologies (DLTs) could provide such a platform, blockchains, such as\nBitcoin, were not designed with IoT networks in mind, hence are often\nunsuitable for such applications: they offer poor transaction throughput and\nconfirmation times, put stress on constrained computing and storage resources,\nand require high transaction fees. In this work, we consider a class of\nIoT-friendly DLTs based on directed acyclic graphs, rather than a blockchain,\nand with a reputation system in the place of Proof of Work (PoW). However,\nwithout PoW, implementation of these DLTs requires an access control algorithm\nto manage the rate at which nodes can add new transactions to the ledger. We\nmodel the access control problem and present an algorithm that is fair,\nefficient and secure. Our algorithm represents a new design paradigm for DLTs\nin which concepts from networking are applied to the DLT setting for the first\ntime. For example, our algorithm uses distributed rate setting which is similar\nin nature to transmission control used in the Internet. However, our solution\nfeatures novel adaptations to cope with the adversarial environment of DLTs in\nwhich no individual agent can be trusted. Our algorithm guarantees utilisation\nof resources, consistency, fairness, and resilience against attackers. All of\nthis is achieved efficiently and with regard for the limitations of IoT\ndevices. We perform extensive simulations to validate these claims.\n
In 2015, the United Nations (UN) member states identified 17 Sustainable Development Goals (SDGs) to be fulfilled by 2030. SDGs are an urgent global call for action to provide a blueprint for shared prosperity in a sustainable world. At a European level, in December 2019, the European Green Deal was presented, a roadmap to implement the UN 2030 agenda with a commitment to a growth strategy that will turn environmental challenges into opportunities across all policy areas. To achieve these SDGs, blockchain is one of the key enabling technologies that can help to create sustainable and secure solutions, since it is able to deliver accountability, transparency, traceability, and cyber-resilience, as well as to provide a higher operational efficiency in global partnerships. This chapter overviews the potential of blockchain to face sustainability challenges by describing several relevant applications. Finally, different open challenges and recommendations are enumerated with the aim of guiding all the stakeholders committed to the development of cyber-resilient and high-impact sustainable solutions.
Alma E. Guerrero-Sánchez, Edgar A. Rivas-Araiza, Jose L. Gonzalez-Cordoba, Manuel Toledano‐Ayala · 5 authors
The Internet of Things (IoT) paradigm allows the connection and exchange of information between millions of smart devices. This paradigm grows and develops exponentially as do the risks and attacks on IoT infrastructures. Security, privacy, reliability, and autonomy are the most important requirements in IoT Systems. If these issues are not guaranteed, the IoT system could be susceptible to malicious users and malicious use. In centralized IoT systems, attacks and risks are greater, especially when data is transmitted between devices and shared with other organizations. To avoid these types of situations, this work presents a decentralized system that guarantees the autonomy and security of an IoT system. The proposed methodology helps to protect data integrity and availability based on the security advantages provided by blockchain and the use of cryptographic tools. The accuracy of the proposed methodology was measured on a temperature and humidity sensing IoT-based Wireless Sensor Network (WSN). The obtained results prove that the proposal fulfils the main requirements of an IoT system. It is autonomous, secure to share and send information between devices and users, has privacy, it is reliable, and the information is available in the infrastructure. Furthermore, this research demonstrates that the proposal is less susceptible to the most frequent attacks against IoT systems, such as linking attack, man in the middle, and Distributed Denial of Service (DDoS) attack.
We present a novel game-theoretic, Bayesian reinforcement learning (RL) and deep learning (DL) framework to represent interactions of miners in public and consortium blockchains with mobile edge computing (MEC). Within the framework, we formulate a stochastic game played by miners under incomplete information. Each miner can offload its block operations to one of the base stations (BSs) equipped with the MEC server. The miners select their offloading BSs and block processing rates simultaneously and independently, without informing other miners about their actions. As such, no miner knows the past and current actions of others and, hence, constructs its belief about these actions. Accordingly, we devise a Bayesian RL algorithm based on the partially-observable Markov decision process for miner's decision making that allows each miner to dynamically adjust its strategy and update its beliefs through repeated interactions with each other and with the mobile environment. We also propose a novel unsupervised Bayesian deep learning algorithm where the uncertainties about unobservable states are approximated with Bayesian neural networks. We show that the proposed Bayesian RL and DL algorithms converge to the stable states where the miners' actions and beliefs form the perfect Bayesian equilibrium (PBE) and myopic PBE, respectively.
BACKGROUND: Blockchain offers a promising new distributed technology to address the challenges of data standardization, system interoperability, security, privacy, and accessibility of medical records. OBJECTIVE: The purpose of this review is to assess the research on the use of blockchain technology for patient care and the associated challenges and to provide a research agenda for future research. METHODS: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. We queried the Cumulative Index of Nursing and Allied Health Literature (CINAHL), PubMed, Excerpta Medica dataBASE (EMBASE), and Web of Science databases for peer-reviewed research articles published up to December 2019 that examined the implementation of blockchain technology in health care settings. We identified 800 articles from which we selected 70 empirical research articles for a detailed review. RESULTS: Blockchain-based patient care applications include medical information systems, personal health records, mobile health and telemedicine, data preservation systems and social networks, health information exchanges and remote monitoring systems, and medical research systems. These blockchain-based health care applications may improve patient engagement and empowerment, improve health care provider access to information, and enhance the use of health care information for medical research. CONCLUSIONS: Blockchain health information technology (HIT) provides benefits such as ensuring data privacy and security of health data, facilitating interoperability of heterogeneous HIT systems, and improving the quality of health care outcomes. However, barriers to using blockchain technology to build HIT include security and privacy vulnerabilities, user resistance, high computing power requirements and implementation costs, inefficient consensus algorithms, and challenges of integrating blockchain with existing HIT. With 51% of the research focused on medical information systems such as electronic health record and electronic medical record, and 53% of the research focused on data security and privacy issues, this review shows that HIT research is primarily focused on the use of blockchain technologies to address the current challenges HIT faces. Although Blockchain presents significant potential for disrupting health care, most ideas are in their infancy.
Blockchain technologies have drawn massive attention to the world these past few years mostly because of the burst of cryptocurrencies like Bitcoin, Etherium, Ripple and many others. A Blockchain, also known as distributed ledger technology, has demonstrated huge potential in saving time and costs. This open-source technology which generates a decentralized public ledger of transactions is widely appreciated for ensuring a high level of privacy through encryption and thus sharing the transaction details only amongst the participants involved in the transactions. The Blockchain is used not only for cryptocurrency but also by various companies to meet their business ends, such as efficient management of supply chains and logistics. The rise and fall of numerous crypto-currencies based on blockchain technology have generated debate among tech-giants and regulatory bodies. There are various groups which are working on standardizing the blockchain technology. At the same time, numerous groups are actively working, developing and fine-tuning their own blockchain platforms. Platforms such as etherium, hyperledger, parity, etc. have their own pros and cons. This research is focused on the performance analysis of blockchain platforms which gives a comparative understanding of these platforms.
Internet of Things (IoT) is a set of technologies that enable network-connected devices to perform an action or share data among several connected devices or to a shared database. The actions can be anything from switching on an Air Conditioning device remotely to turning on the ignition of a car through a command issued from a remote location or asking Alexa or Google Assistant to search for weather conditions in an area. IoT has proved to be game-changing for many industries such as Supply Chain, Shipping and Transportation providing updates on the status of shipments in real time. This has resulted in a huge amount of data created by a lot of these devices all of which need to be processed in real time. In this thesis, we propose a method to collect sensor data from IoT devices and use blockchain to store and retrieve the collected data in a secure and decentralized fashion within a closed system, suitable for a single enterprise or a group of companies in industries like shipping where sharing data with each other is required. Much like blockchain, we envision a future where IoT devices can connect and disconnect to distributed systems without causing downtime for the data collection or storage or relying on a cloud-based storage system for synchronizing data between devices. We also look at how the performance of some of these distributed systems like Inter Planetary File System (IPFS) and Ethereum Swarm compare on low-powered devices like the raspberry pi.
Data is one of the most significant resources. In this digital era, cyber security has become the worldwide issue. Since cyber criminals are getting progressively skilful in their attempts to destroy the valuable data, securing this data has become mandatory. Different procedures have been developed in the past to secure the data, but there are no bounds to security threats, resulting in theft of information from the devices. Currently Blockchain technology is the best tool to secure the data. Blockchain, originally known as Bitcoin, has become very popular technology to digitally create and manage transactions. It is a form of distributed public ledger which analyses and verifies transactions in decentralized manner and data is not under the control of any third party organization. This rapidly evolving technology can possibly change the opinion about digital transactions in various areas such as energy supply, peer-to-peer global payments, financial transactions, agriculture and industry. Regardless, this rising innovation is still in its beginning period of progression. Inspite of several opportunities offered by blockchain, it has limitations such as transaction cost, scalability, consistency security and administration issues which has not yet been addressed and investigated. In spite of the fact that there are a couple of studies on the security and privacy issues of the blockchain, they do not have an efficient assessment of the securing blockchain architectures. This paper presents a detailed architecture of blockchain technology along with systematic study of the security attacks rising in blockchain technology.
is a problem that defines a mechanism for how to safely bring external data to the blockchain. Although there have been various research efforts to solve this problem, existing solutions are limited in that they do not support either data availability or data integrity. Furthermore, no solution has been proposed to minimize the response time when an oracle server is malicious or overloaded. This paper proposes a distributed oracle using Intel Software Guard Extensions (SGX). The proposed approach uses multiple oracle servers to support data availability. It also supports data integrity using Intel SGX and Transport Layer Security (TLS) communication. The reputation system, which favors oracle servers with short response times, minimizes the average response time even if some of the oracle servers are malicious. The benchmarking results show that the response time of the proposed approach with 3 oracle servers is only 14% slower than a centralized oracle called Town-crier and scales well even if the number of oracle servers is increased up to 9. The reputation system is also evaluated, and its feasibility is analyzed using various experiments.
Yu-Tse Lee, Jhan-Jia Lin, Jane Yung-jen Hsu, Ja‐Ling Wu
This paper presents a blockchain-based time bank system on the basis of the Hyperledger Fabric framework, which is one of the permissioned blockchain networks. Most of the services provided by existing Time Bank systems were recorded and conducted manually in the past; furthermore, jobs for matching services with receivers were managed by people. Running a time bank in this way will cost lots of time and human resources and, worse, it lacks security. This work designs and realizes a time bank system enabling all the service-related processes being executed and recorded on a blockchain. The matching between services’ supply-and-demand tasks can directly be done through autonomous smart contracts. Building a time bank system on blockchain benefits the transaction of time credit which plays the role of digital currency on the system. In addition, the proposed time bank also retains a grading system, allowing its members to give each other a grade for reflecting their degrees of satisfaction about the results provided by the system. This grading system will incentivize the members to provide a better quality of service and adopt a nicer attitude for receiving a service, which may positively endorse the development of a worldwide time bank system.
Yan Zhuang, Yin-Wu Chen, Zon‐Yin Shae, Chi‐Ren Shyu
BACKGROUND: Data coordination across multiple health care facilities has become increasingly important for many emerging health care applications. Distrust has been recognized as a key barrier to the success of such applications. Leveraging blockchain technology could provide potential solutions tobuild trust between data providers and receivers by taking advantage of blockchain properties such as security, immutability, anonymity, decentralization, and smart contracts. Many health technologies have empirically proven that blockchain designs fit well with the needs of health care applications with certain degrees of success. However, there is a lack of robust architecture to provide a practical framework for developers to implement applications and test the performance of stability, efficiency, and scalability using standard blockchain designs. A generalized blockchain model is needed for the health care community to adopt blockchain technology and develop applications in a timely fashion. OBJECTIVE: This study aimed at building a generalized blockchain architecture that provides data coordination functions, including data requests, permission granting, data exchange, and usage tracking, for a wide spectrum of health care application developments. METHODS: An augmented, 3-layered blockchain architecture was built on a private blockchain network. The 3 layers, from bottom to top, are as follows: (1) incorporation of fundamental blockchain settings and smart contract design for data collection; (2) interactions between the blockchain and health care application development environment using Node.js and web3.js; and (3) a flexible development platform that supports web technologies such as HTML, https, and various programing languages. Two example applications, health information exchange (HIE) and clinical trial recruitment, were developed in our design to demonstrate the feasibility of the layered architecture. Case studies were conducted to test the performance in terms of stability, efficiency, and scalability of the blockchain system. RESULTS: A total of 331,142 simulated HIE requests from accounts of 40,000 patients were successfully validated through this layered blockchain architecture with an average exchange time of 11.271 (SD 2.208) seconds. We also simulated a clinical trial recruitment scenario with the same set of patients and various recruitment criteria to match potential subjects using the same architecture. Potential subjects successfully received the clinical trial recruitment information and granted permission to the trial sponsors to access their health records with an average time of 3.07 seconds. CONCLUSIONS: This study proposes a generalized layered blockchain architecture that offers health technology community blockchain features for application development without requiring developers to have extensive experience with blockchain technology. The case studies tested the performance of our design and empirically proved the feasibility of the architecture in 2 relevant health application domains.
Yan Zhuang, Lincoln Sheets, Yin-Wu Chen, Zon‐Yin Shae · 6 authors
Health Information Exchange (HIE) exhibits remarkable benefits for patient care such as improving healthcare quality and expediting coordinated care. The Office of the National Coordinator (ONC) for Health Information Technology is seeking patient-centric HIE designs that shift data ownership from providers to patients. There are multiple barriers to patient-centric HIE in the current system, such as security and privacy concerns, data inconsistency, timely access to the right records across multiple healthcare facilities. After investigating the current workflow of HIE, this paper provides a feasible solution to these challenges by utilizing the unique features of blockchain, a distributed ledger technology which is considered "unhackable". Utilizing the smart contract feature, which is a programmable self-executing protocol running on a blockchain, we developed a blockchain model to protect data security and patients' privacy, ensure data provenance, and provide patients full control of their health records. By personalizing data segmentation and an "allowed list" for clinicians to access their data, this design achieves patient-centric HIE. We conducted a large-scale simulation of this patient-centric HIE process and quantitatively evaluated the model's feasibility, stability, security, and robustness.
This paper seeks to use artificial intelligence blockchain algorithms to ensure safe verification of medical institution PHR data and accurate verification of medical data as existing vulnerabilities. Artificial intelligence has recently spread and has led to research on many technologies thanks to the Fourth Industrial Revolution. This is a very important factor in healthcare as well as the healthcare industry’s position. Likewise, blockchain is very safe to apply because it encrypts and verifies these medical data in case they are hacked or leaked. These technologies are considered very important. This study raises the problems of these artificial intelligence blockchains and recognizes blockchain, artificial intelligence, neural networks, healthcare, etc.; these problems clearly exist, so systems like EHR are not being used. In the future, ensuring privacy will be made easier when these EHRs are activated and data transmission and data verification between hospitals are completed. To overcome these shortcomings, we define an information security blockchain artificial intelligence framework and verify blockchain systems for accurate extraction, storage, and verification of data. In addition, various verification and performance evaluation indicators are set to obtain the TPS of medical data and for the implementation of standardization work in the future. This paper seeks to maximize the confidentiality of blockchain and the sensitivity and availability of artificial intelligence.
Jannik Lockl, Vincent Schlatt, André Schweizer, Nils Urbach · 5 authors
The Internet of Things (IoT) describes the concept of physical objects equipped with identifying, sensing, networking, and processing capabilities being connected to the Internet. Architectures for the IoT typically rely on transmitting data to centralized cloud servers for processing. Although cloud services are supposed to enhance the IoT in storage, computation, and communication capabilities, this approach often generates isolated data silos and requires trust in third parties operating the cloud servers, which become single point of failure. In addition, centralized cloud-based applications lack transparency and allow for undetected manipulation and concealment of IoT data. To overcome these downsides, we develop and evaluate a blockchain-based IoT sensor data logging and monitoring system, employing a design science research approach. In this article, we show that such systems should provide modularity, data parsimony, and availability in addition to domain-specific principles. The prototype improves data integrity and availability but uncovers challenges, such as high operating costs through smart contract computation fees. Furthermore, semistructured interviews with practitioners allowed us to derive insights for developing blockchain-based IoT ecosystems and reveal that cooperation with organizations is key for transferring solutions into production. We contribute to the IoT knowledge base by providing design principles as well as managerial and technological recommendations.