Renewable energy sources were introduced as an alternative to fossil fuel sources to make electricity generation cleaner. However, today's renewable energy markets face a number of limitations, such as inflexible pricing models and inaccurate consumption information. These limitations can be addressed with a decentralized marketplace architecture. Such architecture requires a mechanism to guarantee that all marketplace operations are executed according to predefined rules and regulations. One of the ways to establish such a mechanism is blockchain technology. This work defines a decentralized blockchain-based peer-to-peer (P2P) energy marketplace which addresses actors' privacy and the performance of consensus mechanisms. The defined marketplace utilizes private permissioned Ethereum-based blockchain client Hyperledger Besu (HB) and its smart contracts to automate the P2P trade settlement process. Also, to make the marketplace compliant with energy trade regulations, it includes the regulator actor, which manages the issue and consumption of guarantees of origin and certifies the renewable energy sources used to generate traded electricity. Finally, the proposed marketplace incorporates privacy-preserving features, allowing it to generate private transactions and store them within a designated group of actors. Performance evaluation results of HB-based marketplace with three main consensus mechanisms for private networks, i.e., Clique, IBFT 2.0, and QBFT, demonstrate a lower throughput than another popular private permissioned blockchain platform Hyperledger Fabric (HF). However, the lower throughput is a side effect of the Byzantine Fault Tolerant characteristics of HB's consensus mechanisms, i.e., IBFT 2.0 and QBFT, which provide increased security compared to HF's Crash Fault Tolerant consensus RAFT.

This paper works towards an initial ontology of assessment techniques for building AI-enriched human-centered XR systems, denoted Intelligent Realities (IRs). Rather than connecting technologies, our work analyses the characteristics and requirements of IRs of being 'human-centered' and creates an ontology of techniques to assess and measure these features. To achieve this, we use an approach based on Formal Concept Analysis (FCA) to establish a concept hierarchy from a set of critical concepts in the area and their properties. The novel concept defines a metrology, i.e., a set of concepts and units of measurement that can be used to shape the architecture of human-centered XR and metaverse systems. Our work focuses particularly on the ethical and privacy needs of system design. 

During the last decade, we have witnessed a rapiddevelopment of extended reality (XR) technologies such asaugmented reality (AR) and virtual reality (VR). Further, therehave been tremendous advancements in artificial intelligence(AI) and machine learning (ML). These two trends will havea significant impact on future digital societies. The vision ofan immersive, ubiquitous, and intelligent virtual space opensup new opportunities for creating an enhanced digital world inwhich the users are at the center of the development process,so-calledintelligent realities(IRs).The “Human-Centered Intelligent Realities” (HINTS) profileproject will develop concepts, principles, methods, algorithms,and tools for human-centered IRs, thus leading the wayfor future immersive, user-aware, and intelligent interactivedigital environments. The HINTS project is centered aroundan ecosystem combining XR and communication paradigms toform novel intelligent digital systems.HINTS will provide users with new ways to understand,collaborate with, and control digital systems. These novelways will be based on visual and data-driven platforms whichenable tangible, immersive cognitive interactions within realand virtual realities. Thus, exploiting digital systems in a moreefficient, effective, engaging, and resource-aware condition.Moreover, the systems will be equipped with cognitive featuresbased on AI and ML, which allow users to engage with digitalrealities and data in novel forms. This paper describes theHINTS profile project and its initial results. ©2023, Copyright held by the authors   

This work defines a decentralized blockchain-based peer-to-peer (P2P) energy marketplace which addresses actors' privacy and the performance of consensus mechanisms. The defined marketplace utilizes private permissioned Ethereum-based blockchain client Hyperledger Besu (HB) and its smart contracts to automate the P2P trade settlement process. Also, to make the marketplace compliant with energy trade regulations, it includes the regulator actor, which manages the issue and generation of guarantees of origin and certifies the renewable energy sources used to generate traded electricity. Finally, the proposed marketplace incorporates privacy-preserving features, allowing it to generate private transactions and store them within a designated group of actors. Performance evaluation results of HB-based marketplace with three main consensus mechanisms for private networks, i. e., Clique, IBFT 2.0, and QBFT, demonstrate a lower throughput than another popular private permissioned blockchain platform Hyperledger Fabric (HF). However, the lower throughput is a side effect of the Byzantine Fault Tolerant characteristics of HB's consensus mechanisms, i. e., IBFT 2.0 and QBFT, which provide increased security compared to HF's Crash Fault Tolerant consensus RAFT. © 2023 IEEE.

Renewable energy sources are becoming increasingly important as a substitute for fossil energy production. However, distributed renewable energy production faces several challenges regarding trading and management, such as inflexible pricing models and inaccurate green consumption information. A decentralized peer-to-peer (P2P) electricity marketplace may address these challenges. It enables prosumers to market their self-produced electricity. However, such a marketplace needs to guarantee that the transactions follow market rules and government regulations, cannot be manipulated, and are consistent with the generated electricity. One of the ways to provide these guarantees is to leverage blockchain technology.

This work describes a decentralized blockchain-based P2P energy marketplace addressing privacy, trust, and governance issues. It uses a private permissioned blockchain Hyperledger Fabric (HF) and its smart contracts to perform energy trading settlements. The suggested P2P marketplace includes a particular regulator actor acting as a governmental representative overseeing marketplace operations. In this way, the suggested P2P marketplace can address the governance issues needed in electricity marketplaces. Further, the proposed marketplace ensures actors’ data privacy by employing HF’s private data collections while preserving the integrity and auditability of all operations. We present an in-depth performance evaluation and provide insights into the security and privacy challenges emerging from such a marketplace. The results demonstrate that partial centralization by the applied regulator does not limit the P2P energy trade settlement execution. Blockchain technology allows for automated marketplace operations enabling better incentives for prosumer electricity production. Finally, the suggested marketplace preserves the user’s privacy when P2P energy trade settlements are conducted.

The fifth generation (5G) mobile network brings significant new capacity and opportunity to network operators while also creating new challenges and additional pressure to build and operate networks differently. The transformation to 5G mobile networks creates the opportunity to virtualize significant portions of the radio access (RAN) and network core, allowing operators to better compete with over-the-top and hyperscaler offerings. This book covers the business and technical areas of virtualization that enable the transformation and innovation that today’s operators are seeking. It identifies forward-looking gaps where the technology continues to develop, specifically packet acceleration and timing requirements, which today are still not fully virtualized. The book shows you the operational and support considerations, development and lifecycle management, business implications, and vendor-team dynamics involved in deploying a virtualized network. Packed with key concepts of virtualization that solve a broad array of problems, this is an essential reference for those entering this technical domain, those that are going to build and operate these networks, and those that are seeking to learn more about the telecom network. It illustrates why you just can’t do it all in the cloud today.

The demand for large-scale diverse datasets is rapidly increasing due to the advancements in AI services impacting day-to-day life. However, gathering such massive datasets still remains a critical challenge in the AI service engineering pipeline, especially in the computer vision domain where labeled data is scarce. Rather than isolated data collection, crowdsourcing techniques have shown promising potential to achieve the data collection task in a time and cost-efficient manner. In the existing crowdsourcing marketplaces, the crowd works to fulfill consumer-defined requirements where in the end consumer gains the data ownership and the crowd is compensated with task-based payment. On the contrary, this work proposes a blockchain-based decentralized marketplace named Vision Sovereignty Data Marketplace (ViSDM), in which the crowd works to fulfill global requirements & holds data ownership, the consumers pay a certain data price to perform a computing task (model training/testing), the data price is distributed among the crowd in a one-to-many manner through smart contracts, thus allowing the crowd to gain profit from each consumer transaction occurring on their data. The marketplace is implemented as multiple smart contracts and is evaluated based on blockchain-transaction gas fees for the stakeholder interaction & by running scenarios-based simulations. Furthermore, discussions address the challenges included in maintaining data quality and the future milestones towards deployment. © 2023 Owner/Author.

The size and diversity of the training datasets directly influences the decision-making process of AI models. Therefore, there is an immense need for massive and diverse datasets to enhance the deployment process of AI applications. Crowdsourcing marketplaces provide a fast and reliable alternative to the laborious data collection process. However, the existing crowdsourcing marketplaces are either centralized or do not fully provide data sovereignty. By contrast, this work proposes a decentralized crowdsourcing platform through prototypical implementation along with active involvement of business entities, that grants the users sovereignty over their collected data, named as Vision-Sovereignty Data Marketplace (ViSDM). This work contributes to the data marketplaces landscape by introducing (i) A liquid democracy-based voting system to negotiate prices between a buyer and multiple data owners, (ii) An automated AI-Based per-sample value calculation function to evaluate the data and distribute profit among the data owners. © 2023 Owner/Author.

Digital marketplaces were created recently to accelerate the delivery of applications and services to customers. Their appealing feature is to activate and dynamize the demand, supply, and development of digital goods, applications, or services. By being an intermediary between producer and consumer, the primary business model for a marketplace is to charge the producer with a commission on the amount paid by the consumer. However, most of the time, the commission is dictated by the marketplace facilitator itself and creates an imbalance in value distribution, where producer and consumer sides suffer monetarily. In order to eliminate the need for a centralized entity between the producer and consumer, a blockchain-based decentralized digital marketplace concept was introduced. It provides marketplace actors with the tools to perform business transactions in a trusted manner and without the need for an intermediary. In this work, we provide a survey on Telecommunication Services Marketplaces (TSMs) which employ blockchain technology as the main trust enabling entity in order to avoid any intermediaries. We provide an overview of scientific and industrial proposals on the blockchain-based online digital marketplaces at large, and TSMs in particular. We consider in this study the notion of telecommunication services as any service enabling the capability for information transfer and, increasingly, information processing provided to a group of users by a telecommunications system. We discuss the main standardization activities around the concepts of TSMs and provide particular use-cases for the TSM business transactions such as SLA settlement. Also, we provide insights into the main foundational services provided by the TSM, as well as a survey of the scientific and industrial proposals for such services. Finally, a prospect for future developments is given. Author