Blockchain based energy transactions for a prosumer community

PhD thesis in Information technologyIntegration of solar micro-generation capabilities in domestic contexts is on the rise, leading to the creation of prosumer communities who generate part of the energy they consume. Prosumer communities require a decentralized, transparent and immutable transaction system in order to extract value from their surplus energy generation and usage flexibility. The aim of this study is to develop frameworks and methods to create such a prosumer transaction system with self enforcing smart contracts to facilitate trading of energy assets such as electricity units, energy flexibility incentives and storage credits. Blockchain is a transparent, distributed ledger for consensus based transaction processing maintained by a network of peer nodes. Hyperledger Fabric is a blockchain platform that offers the added benefits of lower operating cost, faster transaction processing, user authentication based access control and support for self enforcing smart contracts. This thesis investigates the applicability of Hyperledger Fabric to tokenize and transact energy assets in a unified transaction system. Data driven approaches to implement an incentive based energy flexibility system for peak mitigation on the blockchain are also investigated. To this end, the stakeholders for such a transaction management system were identified and their business relationships and interactions were described. Energy assets were encapsulated into blockchain tokens and algorithms were developed and encoded into self enforcing smart contracts based on the stakeholder relationships. A unified transaction framework was proposed that would bring on board all the stakeholders, their trading relationships and the assets being transacted. Tokens and methods in the transaction system were implemented in fungible and non fungible versions and the versions were critically compared in terms of application area, design, algorithmic complexity, performance, advantages and disadvantages. Further, with a focus on energy flexibility applications, a prosumer research dataset was analysed to gain insights into the production and consumption behaviors. Based on these insights, a data driven approach for peak mitigation was proposed and implemented on the Hyperledger Fabric blockchain. The thesis thus addresses different aspects of a blockchain based prosumer transaction system, and shows the feasibility of proposed approaches through implementation and performance testing of proofs of concept

Framework for Client-Server Distributed Database System for an Integrated Pay Roll System

A pay roll is a list of companies’ employees and the amount of money that they are to be paid at the end of each work schedule, hourly, weekly or monthly. In a company, pay roll is the sum of all financial records of salaries of an employee, wages, bonuses and deductions.A nominal roll is a list containing employee details in a particular organization. An integrated pay roll system is an automated (computer based) pay roll system where individual autonomous pay roll system of an organizations are networked together to form a distributed pay roll system. This is initiated to ease pay roll transaction processing, improve transparency in pay roll processing and to reduce duplication of pay roll processing functions.The research work is to create a distributed pay roll system for local government areas in Bayelsa Sate. The system consists of a relational database of pay roll variables which could be shared by the various Local Government Areas of Bayelsa State. Each LGA will form a site. The database will be hosted by the server at the local government Service Commission office. All LGAs will access the database via a distributed network. The client/server distributed network architecture is used in the design and implementation of the system. The system is capable of monitoring an employee’s nominal roll and pay roll records from the day of resumption of duty to the day of retirement, detection of an employee working in more than one local government, generation of reports concerning an employee or set of employees for promotion, demotion or retirement as the case may be, and automatic monthly pay roll computation.

Using distributed OLTP technology in a high performance storage system

The design of scaleable mass storage systems requires various system components to be distributed across multiple processors. Most of these processes maintain persistent database-type information (i.e., metadata) on the resources they are responsible for managing (e.g., bitfiles, bitfile segments, physical volumes, virtual volumes, cartridges, etc.). These processes all participate in fulfilling end-user requests and updating metadata information. A number of challenges arise when distributed processes attempt to maintain separate metadata resources with production-level integrity and consistency. For example, when requests fail, metadata changes made by the various processes must be aborted or rolled back. When requests are successful, all metadata changes must be committed together. If all metadata changes cannot be committed together for some reason, then all metadata changes must be rolled back to the previous consistent state. Lack of metadata consistency jeopardizes storage system integrity. Distributed on-line transaction processing (OLTP) technology can be applied to distributed mass storage systems as the mechanism for managing the consistency of distributed metadata. OLTP concepts are familiar to manN, industries such as banking and financial services but are less well known and understood in scientific and technical computing. As mass storage systems and other products are designed using distributed processing and data-management strategies for performance, scalability, and/or availability reasons, distributed OLTP technology can be applied to solve the inherent challenges raised by such environments. This paper discusses the benefits in using distributed transaction processing products. Design and implementation experiences using the Encina OLTP product from Transarc in the High Performance Storage System are presented in more detail as a case study for how this technology can be applied to mass storage systems designed for distributed environments

The End of a Myth: Distributed Transactions Can Scale

The common wisdom is that distributed transactions do not scale. But what if distributed transactions could be made scalable using the next generation of networks and a redesign of distributed databases? There would be no need for developers anymore to worry about co-partitioning schemes to achieve decent performance. Application development would become easier as data placement would no longer determine how scalable an application is. Hardware provisioning would be simplified as the system administrator can expect a linear scale-out when adding more machines rather than some complex sub-linear function, which is highly application specific. In this paper, we present the design of our novel scalable database system NAM-DB and show that distributed transactions with the very common Snapshot Isolation guarantee can indeed scale using the next generation of RDMA-enabled network technology without any inherent bottlenecks. Our experiments with the TPC-C benchmark show that our system scales linearly to over 6.5 million new-order (14.5 million total) distributed transactions per second on 56 machines.Comment: 12 page

Designing Software Architectures As a Composition of Specializations of Knowledge Domains

This paper summarizes our experimental research and software development activities in designing robust, adaptable and reusable software architectures. Several years ago, based on our previous experiences in object-oriented software development, we made the following assumption: ‘A software architecture should be a composition of specializations of knowledge domains’. To verify this assumption we carried out three pilot projects. In addition to the application of some popular domain analysis techniques such as use cases, we identified the invariant compositional structures of the software architectures and the related knowledge domains. Knowledge domains define the boundaries of the adaptability and reusability capabilities of software systems. Next, knowledge domains were mapped to object-oriented concepts. We experienced that some aspects of knowledge could not be directly modeled in terms of object-oriented concepts. In this paper we describe our approach, the pilot projects, the experienced problems and the adopted solutions for realizing the software architectures. We conclude the paper with the lessons that we learned from this experience

Chainspace: A Sharded Smart Contracts Platform

Chainspace is a decentralized infrastructure, known as a distributed ledger, that supports user defined smart contracts and executes user-supplied transactions on their objects. The correct execution of smart contract transactions is verifiable by all. The system is scalable, by sharding state and the execution of transactions, and using S-BAC, a distributed commit protocol, to guarantee consistency. Chainspace is secure against subsets of nodes trying to compromise its integrity or availability properties through Byzantine Fault Tolerance (BFT), and extremely high-auditability, non-repudiation and `blockchain' techniques. Even when BFT fails, auditing mechanisms are in place to trace malicious participants. We present the design, rationale, and details of Chainspace; we argue through evaluating an implementation of the system about its scaling and other features; we illustrate a number of privacy-friendly smart contracts for smart metering, polling and banking and measure their performance

The End of Slow Networks: It's Time for a Redesign

Next generation high-performance RDMA-capable networks will require a fundamental rethinking of the design and architecture of modern distributed DBMSs. These systems are commonly designed and optimized under the assumption that the network is the bottleneck: the network is slow and "thin", and thus needs to be avoided as much as possible. Yet this assumption no longer holds true. With InfiniBand FDR 4x, the bandwidth available to transfer data across network is in the same ballpark as the bandwidth of one memory channel, and it increases even further with the most recent EDR standard. Moreover, with the increasing advances of RDMA, the latency improves similarly fast. In this paper, we first argue that the "old" distributed database design is not capable of taking full advantage of the network. Second, we propose architectural redesigns for OLTP, OLAP and advanced analytical frameworks to take better advantage of the improved bandwidth, latency and RDMA capabilities. Finally, for each of the workload categories, we show that remarkable performance improvements can be achieved