Secret Smart Contracts in Hierarchical Blockchains

This article presents the results of an implementation of a new platform based on swarm communication and executable choreographies. In our research of executable choreographies, we have come up with a more general model to implement smart contracts and a generic architecture of systems using hierarchical blockchain architecture. The novel concepts of secret smart contract and near-chain are introduced. The near-chain approach presents a new method to extend the hierarchical blockchain architecture and to improve performance, security and privacy characteristics of general blockchain-based systems. As such, we are subsequently defining and explaining why any extension of blockchain architectures should revolve around three essential dimensions: trustlessness, non-repudiation and tamper resistance. The hierarchical blockchain approach provides a novel perspective, as well as establishing off-chain storages (near-chains) as special types of hierarchical blockchains stored in a distributed file system. Furthermore, we are providing solutions to the difficult blockchain concerns regarding scalability, performance and privacy issues

Data trading based on seller preferences within blockchain smart contract

This thesis was submitted for the award of Master of Philosophy and was awarded by Brunel University LondonOnline data trading has not focused on the necessary control of data selling by the data seller preferences (DSP) using blockchain technology. This research aims to explore the DSP using smart contract over blockchain within the domain of online data trading. Data trading has been carried out for several decades, but cutting-edge technologies and cloud services have grown dramatically worldwide. Industries are gaining benefits from accessing the data that enabled them to perform mission-critical tasks by performing data analysis on the massively available data and getting a higher return on investment (ROI). This research aims to make online data trading possible only if the buyer can satisfy the conditions predefined by the seller. For example, DSP can restrict the data purchase if the participating buyer is doing business from a specific geographic location, or it can further restrict a particular type and size of business. So, data trading will be controlled by smart contract validation based on DSP hence the novel DSP artefact has been achieved and evaluated via a personal blockchain Ganache, which is always set to automatics mining. Even though the DSP Dapp artefact has been explored with a limited scope of seller preferences and data volume, future researchers may evolve the DSP Dapp artefact framework to achieve complex seller preferences such as ethical selling (e.g., green credentials). The smart contract serves as an automated contract depending on DSP, between seller and buyer, without the involvement of any broker or third party. After the first chapter's introduction has set up the context for chapter two to review the literature, present the research question, and set the aims and objectives. Chapter three selected the DSR methodology for this research and analysed the requirements to set the building block for chapters four and five. Chapters four and five fulfilled objective two by designing and developing the DSP artefact using a smart contract to control data trading. Chapter 6 validated the DSP trading system to confirm the novelty of this research, and finally, chapter 7 summarised the contribution and future research. The research proposes a new approach to online data trading that controls the data selling depending on DSP within smart contract over blockchain and opens new doors for the researchers for future work in this area

Blockchain-Based Services Implemented in a Microservices Architecture Using a Trusted Platform Module Applied to Electric Vehicle Charging Stations

Microservice architectures exploit container-based virtualized services, which rarely use hardware-based cryptography. A trusted platform module (TPM) offers a hardware root for trust in services that makes use of cryptographic operations. The virtualization of this hardware module offers high usability for other types of service that require TPM functionalities. This paper proposes the design of TPM virtualization in a container. To ensure integrity, different mechanisms, such as attestation and sealing, have been developed for the binaries and libraries stored in the container volumes. Through a REST API, the container offers the functionalities of a TPM, such as key generation and signing. To prevent unauthorized access to the container, this article proposes an authentication mechanism based on tokens issued by the Cognito Amazon Web Service. As a proof of concept and applicability in industry, a use case for electric vehicle charging stations using a microservice-based architecture is proposed. Using the EOS.IO blockchain to maintain a copy of the data, the virtualized TPM microservice provides the cryptographic operations necessary for blockchain transactions. Through a two-factor authentication mechanism, users can access the data. This scenario shows the potential of using blockchain technologies in microservice-based architectures, where microservices such as the virtualized TPM fill a security gap in these architectures.Infineon TechnologiesProgram “Digitalisierung der EnergiewendeBundesministeriums für Wirtschaft und EnergieTrusted Blockchains fur das offene, intelligente Energienetz der Zukunft (tbiEnergy)FKZ 03EI6029DEuropean Health and Digital Executive Agency (HaDEA) program under Grant Agreement No 101092950 (EDGELESS project)FEDER/Junta de Andalucia-Consejeria de Transformacion Economica, Industria, Conocimiento y Universidades under Project B-TIC-588-UGR20

Report from GI-Dagstuhl Seminar 16394: Software Performance Engineering in the DevOps World

This report documents the program and the outcomes of GI-Dagstuhl Seminar 16394 "Software Performance Engineering in the DevOps World". The seminar addressed the problem of performance-aware DevOps. Both, DevOps and performance engineering have been growing trends over the past one to two years, in no small part due to the rise in importance of identifying performance anomalies in the operations (Ops) of cloud and big data systems and feeding these back to the development (Dev). However, so far, the research community has treated software engineering, performance engineering, and cloud computing mostly as individual research areas. We aimed to identify cross-community collaboration, and to set the path for long-lasting collaborations towards performance-aware DevOps. The main goal of the seminar was to bring together young researchers (PhD students in a later stage of their PhD, as well as PostDocs or Junior Professors) in the areas of (i) software engineering, (ii) performance engineering, and (iii) cloud computing and big data to present their current research projects, to exchange experience and expertise, to discuss research challenges, and to develop ideas for future collaborations

Blockchain Support for Collaborative Business Processes

Blockchain technology provides basic building blocks to support the execution of collaborative business processes involving mutually untrusted parties in a decentralized environment. Several research proposals have demonstrated the feasibility of designing blockchain-based collaborative business processes using a high-level notation, such as the Business Process Model and Notation (BPMN), and thereon automatically generating the code artifacts required to execute these processes on a blockchain platform. In this paper, we present the conceptual foundations of model-driven approaches for blockchain-based collaborative process execution and we compare two concrete approaches, namely Caterpillar and Lorikeet