G. Ravikumar, K. Venkatachalam, Mehedi Masud, Mohamed Abouhawwash
Recently internet of medical things (IoMT) act as a smart doctor using sensor wearable’s device in human body. This smart doctor device senses necessary medical data from human and transfer via network immediately to physician. It is important to transfer sensitive data very securely. Blockchain becomes trending technology to provide high security to both end users in the network. Traditionally security structure is relying on cryptographic techniques which is very expensive and takes more time in securely transmitting data. To overcome this issue, this paper builds a cost effective, blockchain with IoMT using fog-cloud computing. The aim of research is to provide cost effective healthcare services in the present system. This study develops an IoMT systems using fusion of scheduling techniques in blockchain. We propose a Smart Contract with Function Based Cost Efficient Task Scheduling (FTS-SCON) algorithm in blockchain framework. The proposed algorithm uses functions to schedule the task in the blockchain which is cost effective. With the help of cryptography based Blockchain schemes with smart contracts enables consistency and validation of data with symmetric cryptography. Simulation results shows the proposed outperform all existing elements regarding data security, validation by 10%, and cost of application execution by 30% in IoMT.
Farhana Akter Sunny, Petr Hájek, Michal Munk, Mohammad Zoynul Abedin · 7 authors
For this study, the researchers conducted a systematic literature review to answer complex questions about the field of blockchain technology. We used an unbiased systematic review process to find works on blockchain-based applications and developed a Python code that searched various online databases. This paper provides an overview of the characteristics, mode of operation, and applications of blockchains in various domains such as transportation, commerce and industry, privacy and security, the financial sector, government, education, healthcare, and the Internet of Things (IoT). The aim was to identify the key research themes addressed in existing articles within each application domain and suggest future research directions for these domains. We analyzed a set of 750 articles published between 2015 and 2021 that dealt with blockchain applications. We found that financial management and security issues have been the main research focus since 2015. However, the use of blockchain in education has become a central research theme in 2021. Healthcare, IoT, and government applications have also grown in popularity. We furthermore analyzed some of the implementations of privacy mechanisms, as well as the challenges and future directions that need to be addressed for effective blockchain deployment. This study contributes to existing research by providing a comprehensive overview of blockchain application themes and their emerging areas for stakeholders in diverse sectors.
Abdullah Ayub Khan, Asif Ali Wagan, Asif Ali Laghari, Abdul Rehman Gilal · 6 authors
Owing to the sensitive nature of healthcare data, the aforementioned approach to transferring patient data to central servers creates serious security and privacy issues. In addition, blockchain distributed ledger technology has introduced immutable storage and decentralized data management capability, which handles a large number of distributed nodes of E-Healthcare transactions via a serverless network, but in a limited manner because of blockchain-enabled resources. In this scenario, the medical industries are concerned about constituting an innovation in health information preservation and exchanging service delivery protocols without the connectivity of an untrusted third-party infrastructure. In this study, we proposed a blockchain hyperledger fabric-enabled consortium architecture called BIoMT, which provides security, integrity, transparency, and provenance to health-related transactions and exchanges sensitive clinical information in a serverless peer-to-peer (P2P) secure network environment. A consensus is designed and created to reduce the rate of blockchain resource constraints on the Internet of Medical Things (IoMT). The privacy of individual health transactions before sharing is protected using the NuCypher Re-Encryption mechanism, which increases security and provides medical ledger integrity and transparency. Smart contracts are created and deployed to automate device registration, exchange transactions, and ledger preservation in immutable storage (filecoin) after cross verification and validation. The experimental results show that the proposed BIoMT reduces the computational cost by 26.13%, and the robust medical node generation increases to 60.37%. Thus, only 31.79% and 74.21% of IoMT-related information and serverless P2P network usage are maintained and saved, respectively.
With the dramatic increase of the Internet of Medical Things devices, self and remote health data monitoring is consistently receiving more attention. However, medical devices are usually challenging to deploy due to privacy regulations, and they generally leverage a centralized third party. Enabling data sharing would enhance new medical studies, formulate new treatments, and deliver new digital health technologies. Solving the issue will have a triple impact: we will handle sensitive information easily, contribute to international medical advancements, and enable personalized care. A possible solution is to exploit decentralization distributing privacy concerns directly to users. Solutions enabling this vision are closely linked to Distributed Ledger Technologies. Through its characteristics of immutability and transparency, this technology would allow privacy-compliant solutions in contexts where privacy is the first need. This paper envisions the InterPlanetary Health Layer and related real-world implementations in the Internet of Medical Things domain. The main idea of the proposed solution is to handle sensitive data by preserving privacy and guaranteeing data availability. Specifically, users can build their private network, collaboratively authorize operations among their data and manage their privacy conditions without relying on a third party. The results of several stress tests conducted on a real case study confirmed the feasibility of the proposed solution, which shows good scalability and a modest impact on the application performance measured during the decentralized data access.
M.D. Khan, Dirk Schaefer, Jelena Milisavljevic-Syed
Blockchain Technology has gained prominence since 2008 with trust, reliability, speed, and transparency becoming major advantages. It has also been applied and researched within a multitude of industry applications ranging from manufacturing to financial transactions through to real estate. In addition to Artificial Intelligence (AI) and Internet of Things (IoT), Distributed Ledger Technology (DLT) such as blockchain serves as the backbone to the Machine Economy, which is a relatively recent concept in which machines can communicate and exchange data with each other autonomously, allowing manufacturing companies to become more competitive. However, using blockchain for exchanging large volumes of data requires significant fees and energy due to its use of miners to validate transactions which is a barrier for manufacturing companies to implement. Directed Acyclic Graph (DAG), which is a different type of DLT is an example of an alternative to blockchain which aims to overcome most of the problems currently on the blockchain and promises to enable fee-less transactions with much lower power requirements than blockchain. In this paper, the authors explore the DLT aspect of the machine economy within the manufacturing context. Firstly, the enabling DLT technical attributes of the machine economy are analysed. This is followed by an evaluation of all DLT’s, focusing on the challenges and benefits of each alternative. Following on from this, a cross comparison of each DLT type is done which leads into a discussion and future directions to be drawn.
Blockchain is the next generation of secure data management that creates near-immutable decentralized storage. Secure cryptography created a niche for blockchain to provide alternatives to well-known security compromises. However, design bottlenecks with traditional blockchain data structures scale poorly with increased network usage and are extremely computation-intensive. This made the technology difficult to combine with limited devices, like those in Internet of Things networks. In protocols like IOTA, replacement of blockchain’s linked-list queue processing with a lightweight dynamic ledger showed remarkable throughput performance increase. However, current stochastic algorithms for ledger construction suffer distinct trade-offs between efficiency and security. This work proposed a machine-learning approach with a multi-arm bandit that resolved these issues and was designed for auditing on limited devices. This algorithm was tested in a reinforcement-learning environment simulating the IOTA ledger’s construction with a decision tree. This study showed through regret analysis and experimentation that this approach was secure against impulse manipulation attacks while remaining energy-efficient. Although the IOTA protocol was a pioneer for lightweight distributed ledgers, it is expected that future blockchain protocols will adopt techniques similar to those presented in this work.
Network slicing is one of the fundamental tenets of Fifth Generation (5G)/Sixth Generation (6G) networks. Deploying slices requires end-to-end (E2E) control of services and the underlying resources in a network substrate featuring an increasing number of stakeholders. Beyond the technical difficulties this entails, there is a long list of administrative negotiations among parties that do not necessarily trust each other, which often requires costly manual processes, including the legal construction of neutral entities. In this context, Blockchain comes to the rescue by bringing its decentralized yet immutable and auditable lemdger, which has a high potential in the telco arena. In this sense, it may help to automate some of the above costly processes. There have been some proposals in this direction that are applied to various problems among different stakeholders. This paper aims at structuring this field of knowledge by, first, providing introductions to network slicing and blockchain technologies. Then, state-of-the-art is presented through a global architecture that aggregates the various proposals into a coherent whole while showing the motivation behind applying Blockchain and smart contracts to network slicing. And finally, some limitations of current work, future challenges and research directions are also presented.
Metaverse as the latest buzzword has attracted great attention from both industry and academia. Metaverse seamlessly integrates the real world with the virtual world and allows avatars to carry out rich activities including creation, display, entertainment, social networking, and trading. Thus, it is promising to build an exciting digital world and to transform a better physical world through the exploration of the metaverse. In this survey, we dive into the metaverse by discussing how Blockchain and Artificial Intelligence (AI) fuse with it through investigating the state-of-the-art studies across the metaverse components, digital currencies, AI applications in the virtual world, and blockchain-empowered technologies. Further exploitation and interdisciplinary research on the fusion of AI and Blockchain towards metaverse will definitely require collaboration from both academia and industries. We wish that our survey can help researchers, engineers, and educators build an open, fair, and rational future metaverse.
Nowadays, sharding is deemed as a promising way to save traditional blockchain protocols from their low scalability. However, such technique also brings several potential risks and huge communication overheads. An improper design may give rise to the inconsistent state among different committees. Further, the communication overheads arising from cross-shard transactions unfortunately reduce the system's performance. In this paper, we first summarize five essential issues that all sharding blockchain designers face. For each issue, we discuss its key challenge and propose our suggested solutions. In order to break the performance bottlenecks, we propose a reputation mechanism for selecting leaders. The term of reputation in our design reflects each node's honest computation resources. In addition, we introduce a referee committee and partial sets in each committee, and design a recovery procedure in case the leader is malicious. Under the design, we prove that malicious leaders will not hurt the system and will be evicted. Furthermore, we conduct a series of simulations to evaluate our design. The results show that selecting leaders by the reputation can dramatically improve the system performance.
Iqra Khalil, Omer Aziz, Muhammad Shoaib Farooq, Adnan Abid
The concept of decentralization has gained a lot of focus when it comes to Blockchain. The Blockchain technology is a decentralized peer to peer distributed ledger. Many industries have been using Distributed Ledgers (DTL) before the blockchain technology. But the state of the art technology has overshadow the use of all DTLs due to its immutable nature. With the use of this technology new horizons of innovation has been explored. Bitcoin, the first cyrptocurrency, has used the blockchain technology which has received extensive attentions. In this paper, we have addressed the mechanism of the blockchain technology and a detailed tutorial of how to implement it practically. Specifically we have focused on the practical implementation of how to create a blockchain, mine a block and create a cryptocurrency. Secondly, there is detailed discussion on major platform i.e. bitcoin in which blockchain has been explored a lot. Finally towards the end, the Proof of Work Consensus algorithm is elaborated in detail. Our goal is to help readers easily understand the mechanism along with the important features of the blockchain without having to read all the blockchain specifications and application or the state-of-the-art papers that generally describe the system.
Xiaoyang Shi, Hang Xiao, Weifeng Liu, Xi Chen · 7 authors
The distributed consensus mechanism is the backbone of the rapidly developing blockchain network. Blockchain platforms consume vast amounts of electricity based on the current consensus mechanism of Proof-of-Work (PoW). Here, we point out a different consensus mechanism named Proof-of-Stake (PoS) that can eliminate the extensive energy consumption of the current PoW-based blockchain. We comprehensively elucidate the current and projected energy consumption and carbon footprint of the PoW- and PoS-based Bitcoin and Ethereum blockchain platforms. The model of energy consumption of PoS-based Ethereum blockchain can lead the way toward the prediction of other PoS-based blockchain technologies in the future. With the widespread adoption of blockchain technology, if the current PoW mechanism continues to be employed, the carbon footprint of Bitcoin and Ethereum will push the global temperature above 1.5 °C in this century. However, a PoS-based blockchain can reduce the carbon footprint by 99% compared to the PoW mechanism. The small amount of carbon footprint from PoS-based blockchain could make blockchain an attractive technology in a carbon-constrained future. The study sheds light on the urgency of developing the PoS mechanism to solve the current sustainability problem of blockchain.
Fog Radio Access Network (F-RAN) has been regarded as a promising solution to the alleviation of the ever-increasing traffic burden on current and future wireless networks, for it shifts the caching and computing resources from remote cloud to the network edge. However, it makes wireless networks more vulnerable to security attacks as well. To resolve this issue, in this article, we propose a secure yet trustless Blockchain-based F-RAN (BF-RAN), which allows a massive number of trustless devices to form a large-scale trusted cooperative network by leveraging the key features of blockchain, such as decentralization, tamper-proof, and traceability. The architecture of BF-RAN is first presented. Then, the key technologies, including access control, dynamic resource management, and network deployment are discussed. Finally, challenges and open problems in the BF-RAN are identified.
Blockchain is one of the technologies provided by the global distribution of computing power. Simply put, the blockchain is the digital ledger in which transactions are recorded. It all started with a desire to see a new form of security system for transferring confidential files. It aims to achieve many goals like decreasing the process time for transferring files to the other party, and reducing the overall expenses as the files are only transferred across the blockchain network with no need for the files to be uploaded and downloaded to the drive. More effective applications have the ability to share files via the technology of Blockchain. The great challenge is to build a private blockchain environment to send files and distribute them securely between parties, such as military institutions and others. In this paper, a private blockchain is built to overcome the side of the security through a secured file-sharing network. This private Blockchain can be utilized at various institutions. A high scale of security is obtained through using an important algorithm that takes into consideration a critical part of the field of cryptography to robustly encrypt the files. The latter ensures that no individual except for the receiver has the ability to access the files. As well, a sufficient speed was obtained when transferring the files, as compared to Ethereum with FTP. Finally, smart contracts have been designed to suit the transfer of files between nodes.
The oil and gas industry involves a high level of operational expenditure and often faces high risks of asset safety and operational failures. It has never been so important to monitor and control the oil field operations remotely in real-time to ensure safety and efficiency. The traditional monitoring and control systems for oil field operations are typically centralized, prone to failure, and lack efficiency. Blockchain technology mitigates the centralization problem by creating a decentralized, immutable and transparent control environment for automatic monitoring and control of industrial operations. In this study, we propose a blockchain-based IoT framework for real-time monitoring and control to increase oil field operation and asset efficiency and safety. We present the key components of the framework, including the system architecture, operation flows, algorithms, and smart contracts. As a proof-of-concept modeling, a smart contract is developed and validated on a blockchain test platform. A comparative analysis shows the advantages of using blockchain technology and smart contract to provide trustworthy and automatic monitoring and control for oil field operations.
Cong T. Nguyen, Dinh Thai Hoang, Diep N. Nguyen, Eryk Dutkiewicz
Metaverse has recently attracted paramount attention due to its potential for future Internet. However, to fully realize such potential, Metaverse applications have to overcome various challenges such as massive resource demands, interoperability among applications, and security and privacy concerns. In this paper, we propose MetaChain, a novel blockchain-based framework to address emerging challenges for the development of Metaverse applications. In particular, by utilizing the smart contract mechanism, MetaChain can effectively manage and automate complex interactions among the Metaverse Service Provider (MSP) and the Metaverse users (MUs). In addition, to allow the MSP to efficiently allocate its resources for Metaverse applications and MUs’ demands, we design a novel sharding scheme to improve the underlying blockchain’s scalability. Moreover, to leverage MUs’ resources as well as to attract more MUs to support Metaverse operations, we develop an incentive mechanism using the Stackelberg game theory that rewards MUs’ contributions to the Metaverse. Through numerical experiments, we clearly show the impacts of the MUs’ behaviors and how the incentive mechanism can attract more MUs and resources to the Metaverse.
The Internet of things (IoT) is the key enabler of the smart systems used in many areas, from agriculture to aviation, industrial automation to autonomous vehicles. Most IoT deployments employ cost-efficient lightweight devices with limited resources (e.g., bandwidth, energy, storage). Although an IoT network must be built in its simplest form, engineers include more sophisticated devices like gateways and servers to provide web-based services and benefit from cloud systems. So, although the nodes can be widely distributed geographically or topologically, the system becomes centralized, which causes bottlenecks and single-points-of-failure. Furthermore, providing data integrity, nonrepudiation, and event management becomes tricky. In most IoT scenarios, data usually flow from sensors to storage and processing units, whereas event-driven commands and triggers flow from these units to actuators, if any. Therefore, an attacker who gained access to parts of the centralized systems may leak, alter, or remove critical data and may exploit event handling features. This is where blockchain technology can be extremely useful. Using a decentralized ledger as the data storage unit provides integrity, immutability, and nonrepudiation for any IoT deployment. And a customized smart contract lets the IoT deployment benefit from decentralized and immutable (i.e. nonmanipulatable) event management features, too. Further, decentralization provides resilience against availability attacks to a large extent. With this motivation, we introduced a novel IoT architecture that incorporates an Ethereum-based private (Quorum) blockchain running a unique ad-hoc smart contract and a message queue telemetry transport (MQTT) based communication scheme between sensor and actuator nodes. The scheme, the ledger, and the smart contract have also been implemented with several nodes, a broker, and a server all on a PC using Docker containers, where the server was running a forest fire risk detection algorithm as the use case scenario. The proof-of-concept successfully validates the abovesaid functionality, scalability, and efficiency for the given IoT scenario (and some others). Moreover, performance tests showed that an instance of the system with 1000 nodes could stably process and record incoming (sensor) data up to 12.5 transactions per second (TPS) and distribute commands up to 4 TPS, whereas higher TPS is achievable depending on the network conditions and tolerance to losses. The scheme was shown to have polynomial message and time complexity.
Blockchain-based applications come up with cryptocurrencies, especially Bitcoin, introducing a distributed ledger technologies for peer-to-peer networks and essentially records the transactions in blocks containing hash value of the previous blocks. Block generation constitutes the basis of this technology, and the optimization of such systems is among the most crucial concerns. Determining either the block size or the number of transactions in the block brings out a remarkable problem that has been solved by the miners in recent years. First, higher block size results in higher transaction time, on the other hand, smaller block size has many disadvantages such as security, lower transaction fees, lower transaction numbers in a given time interval, which makes it unable to compete with other currency systems due to this bulky structure and higher block generation time. In this study, multiobjective optimization problem (OP) is proposed by minimizing block generation and transmission time. This multiobjective OP is transformed into a single OP by applying weighted sum method. To determine the optimal block size, particle swarm optimization (PSO) algorithm and whale optimization evolutionary algorithm (WOA) are employed. Although both algorithms have capability to reach optimum block size and corresponding time, WOA achieves better performance than PSO in terms of the convergence speed and output fluctuation. Moreover, analysis of the prediction of optimum block size is carried out under different weights which creates many optimization functions. Experimental results indicate that if higher weight is assigned to the transmission time, then block size decreases sharply. Furthermore, the experimental results reveal that design of the blockchain network and number of nodes in network profoundly affect the block size selection due to the time constraints.
Manpreet Kaur, Mohammad Zubair Khan, Shikha Gupta, Abdullah Alsaeedi
It has been proven that Internet of Things (IoT) platforms can improve the performance and efficiency of a wide range of processes. With the acceptance of IoT as a major part of the technology of Industry 4.0, the notion of leveraging the Internet in industries to enable automation and reconfigure existing industrial processes has greatly evolved. By introducing smart technology and intelligent processes, the Industrial Internet of Things (IIoT) is committed to bringing high operational efficiency, enhanced productivity, and effective management to industrial assets. Despite this, the reliance of IIoT on central architecture presents numerous challenges, including the security and maintenance of smart devices, privacy issues owing to third-party participation, and massive computations conducted by a central entity, all of which prevent its widespread adoption in businesses. Emerging blockchain technologies have the potential to transform IIoT platforms and applications. A distributed and decentralized approach followed by blockchain might offer interesting solutions to the challenges raised by IIoT. Furthermore, 5G networks are expected to deliver excellent solutions to meet the demands of decentralized systems, with a focus on application-specific vulnerabilities. Blockchain and IIoT, enabled by 5G, is a viable option to fully explore the potential of contemporary industry. In this context, this article analyzes and examines recent achievements to highlight the major obstacles in blockchain–IIoT convergence and presents a framework for potential solutions. A well-organized literature review by analyzing the existing work in three primary areas: blockchain consensus algorithms used in existing IoT and IIoT applications, blockchain for 5G-enabled IoT networks, and blockchain in industry have been performed, with major findings summarized in each area. Directions for the future are also provided and intend to assist researchers in understanding the full potential of these innovations.
Tooba Faisal, Mischa Döhler, Simone Mangiante, Diego López
It is widely expected that future networks of 6G and beyond will deliver on the unachieved goals set by 5G. Technologies such as Internet of Skills and Industry 4.0 will become stable and viable, as a direct consequence of networks that offer sustained and reliable mobile performance levels. The primary challenges for future technologies are not just low-latency and high-bandwidth. The more critical problem Mobile Service Providers (MSPs) will face will be in balancing the inflated demands of network connections and customers' trust in the network service, that is, being able to interconnect billions of unique devices while adhering to the agreed terms of Service Level Agreements (SLAs). To meet these targets, it is self-evident that MSPs cannot operate in a solitary environment. They must enable cooperation among themselves in a manner that ensures trust, both between themselves as well as with customers. In this study, we present the BEAT (Blockchain-Enabled Accountable and Transparent) Infrastructure Sharing architecture. BEAT exploits the inherent properties of permissioned type of distributed ledger technology (i.e., permissioned distributed ledgers) to deliver on accountability and transparency metrics whenever infrastructure needs to be shared between providers. We also propose a lightweight method that enables device-level accountability. BEAT has been designed to be deployable directly as only minor software upgrades to network devices such as routers. Our simulations on a resource-limited device show that BEAT adds only a few seconds of overhead processing time -- with the latest state-of-the-art network devices, we can reasonably anticipate much lower overheads.
Ensuring a production-ready state of the application under development is the imminent feature of the Continuous Delivery (CD) approach. In a blockchain network, nodes communicate and store data in a distributed manner. Each node executes the same business application but operates in a distinct execution environment. The literature lacks research focusing on continuous practices for blockchain and Distributed Ledger Technology (DLT). Specifically, it lacks such works with support for both design and deployment. The author has proposed a solution that takes into account the continuous delivery of a business application to diverse deployment environments in the DLT network. As a result, two continuous delivery pipelines have been implemented using the Jenkins automation server. The first pipeline prepares a business application whereas the second one generates complete node deployment packages. As a result, the framework ensures the deployment package in the actual version of the business application with the node-specific up-to-date version of deployment configuration files. The Smart Contract Design Pattern has been used when building a business application. The modeling aspect of blockchain network installation has required using Unified Modeling Language (UML) and the UML Profile for Distributed Ledger Deployment. The refined model-to-code transformation generates deployment configurations for nodes. Both the business application and deployment configurations are stored in the GitHub repositories. For the sake of verification, tests have been conducted for the electricity consumption and supply management system designed for prosumers of renewable energy.
Ivan Malakhov, Andrea Marin, Sabina Rossi, Daria Smuseva
In permissioned blockchains, a set of identifiable miners validates transactions and creates new blocks. In scholarship, the proposed solution for the consensus protocol is usually inspired by the Byzantine fault tolerance (BFT) based on voting rather than the proof-of-work (PoW). The advantage of PoW with respect to BFT is that it allows the final user to evaluate the cost required to change a confirmed transaction without the need to trust the consortium of miners. In this paper, we analyse the problems that arise from the application of PoW in permissioned blockchains. In standard PoW, it may be easy for colluded miners to temporarily reach 50% of the total hash power (HP). Moreover, since mining rewards are not usually expected in permissioned contexts, the problem of balancing the computational efforts among the miners becomes crucial. We propose a solution based on a sliding window algorithm to address these problems and analyse its effectiveness in terms of fairness and security. Furthermore, we present a quantitative, analytical model in order to assess its capacity to balance the hash power provided by heterogeneous miners. Our study considers the trade-off between the need to trust the entire consortium of miners guaranteed by the global HP invested by the mining process and the need to prevent collusion among malicious miners aimed at reaching 50% of the total HP. As a result, the model can be used to find the optimal parameters for the sliding window protocol.
Sura I. Mohammed Ali, Haitham Farouk, Hussien Sharaf
Blockchain stores a series of transactions in form of a sequence of linked blocks. Hence, the concept of a single decentralized ledger is easily maintained. Transactions and interactions that take place among the participants accessing the distributed and decentralized but cooperative blockchain network are held through a single ledger. A student information system (SIS) can make use of a decentralized, reliable, and highly trusted ledger that stores vital information. Traditional education systems encounter problems such as centralized record keeping where fault tolerance depends on a single cloud provider; not to mention locally hosted databases. The implementation of blockchain in the education sector provides a new horizon for set of non-functional requirements including but not limited to: security, immutability, independence from the institution, immutability of official records and certificates. In addition, total trust in the accuracy and infallibility are all gathered in the decentralized ledgers of blockchain. The proposed models emphasize on the data availability; represented in students' ability to access all of their data at any time. This paper proposes three models for using blockchains to implement fully functional SIS that maintains transactions such as students’ and faculty members’ records, course registration records and student marks. In addition, avoiding the role of a super administrator or a centralized exposed store where data integrity is vulnerable. Using the proposed models pushes towards an electronic community where genuine certificates can be easily issued and published to the interested parties without the need for involving a centralized administration.
Internet of Things (IoT) is the new paradigm to the scaling nature of things and their elements, interconnected, exchanging data over a network supported with nodes. The Ubiquitous use of tiny devices and embedded sensor frameworks has pushed IoT to the forefront of emerging technologies used in many applications like peer-to-peer networks, smart energy grids, home and building automation, vehicle to vehicle communication, and wearable computing devices. This massive growth and extensive use brought forth security risks that could hinder its commencement in many novel applications. The number of interconnected devices leads the way to several entry points for intruders and, along with it, security risks. The sensitive nature of the IoT applications such as health, automation, and energy grids cannot afford security risks. Traditional security mechanisms will not design or develop to secure such an emerging technology as IoT. Existing technologies have to be relied on with the non-existence of security mechanisms for this purpose. Distributed Ledger Technology (DLT) is one such technology that can reduce the security risks in IoT. The central node vulnerability that can compromise the whole system can be mitigated by eliminating the need for a central node by using the distributed ledger. Blockchain, a distributed ledger technology, has attracted tremendous attention and harnessed in itself a real-world value. However, computationally costly with limited scalability is not entirely suited for the IoT environment. IoT Application (IOTA) technology is the distributed ledger technology that can provide unlimited scalability specifically suitable for the IoT industry. This survey provides an in-depth introduction to how blockchain performs and its constraints in its nature as a generic platform for DLT. In contrast, IOTA is introduced as the technology for IoT, the next-generation blockchain overcoming blockchain’s limitations for its use in IoT.