Entitlement-Based Access Control for Smart Cities Using Blockchain

Smart cities use the Internet of Things (IoT) devices such as connected sensors, lights, and meters to collect and analyze data to improve infrastructure, public utilities, and services. However, the true potential of smart cities cannot be leveraged without addressing many security concerns. In particular, there is a significant challenge for provisioning a reliable access control solution to share IoT data among various users across organizations. We present a novel entitlement-based blockchain-enabled access control architecture that can be used for smart cities (and for any ap-plication domains that require large-scale IoT deployments). Our proposed entitlement-based access control model is flexible as it facilitates a resource owner to safely delegate access rights to any entities beyond the trust boundary of an organization. The detailed design and implementation on Ethereum blockchain along with a qualitative evaluation of the security and access control aspects of the proposed scheme are presented in the paper. The experimental results from private Ethereum test networks demonstrate that our proposal can be easily implemented with low latency. This validates that our proposal is applicable to use in the real world IoT environments.

Towards the integrated assessment of New Zealand pastoral farm systems

Land use and management change is a feature of New Zealand farm systems, driven by a range of factors including volatile markets and exchange rates, variable weather and climate patterns, continuous policy evolution and the inherent innovation of New Zealand farmers. Yet the common indicators used to evaluate the impact of change appear to be limited to the link between productivity (of land/labour/capital) and profitability. However, if farm system "owners" seek truly sustainable systems they should consider a wider set of indicators to guide investment. Sustainability is considered in terms of the ability of the pastoral farm system to fulfil its primary purpose in the long-term, i.e. "to derive value from the natural capital of a land and water resource that is sufficient to support the objectives of the resource owner" and fulfil secondary objectives considered important by other stakeholders (e.g., product and environmental quality). The objective of this study was to develop an integrated assessment framework for sustainability indicators that was useful for guiding change decisions at the farm system scale, a key determinant of regional economic, environmental and social outcomes. The approach is based on the fundamental properties of a complex adaptive system: existence, effectiveness, freedom of action, security, adaptability and coexistence, applied to six key system drivers (financial, environmental, social, cultural, technological and regulatory). This framework could support decision-making in terms of the investment of human, natural and financial capital at the farm system scale and contribute to larger scale information imperatives (e.g., value chains, catchments). Keywords: integrated assessment, pastoral farm systems, sustainability, systems properties

Intergenerational transfers, lifetime welfare, and resource preservation

ABSTRACTThis paper analyzes overlapping-generations models where natural capital is owned by selfish agents. Transfers in favor of young agents reduce the rate of depletion and increase output growth. It is shown that intergenerational transfers may be preferred to laissez-faire by an indefinite sequence of generations: if the resource share in production is sufficiently high, the welfare gain induced by preservation compensates for the loss due to taxation. This conclusion is reinforced when other assets are available, e.g. man-made capital, claims on monopoly rents, and R&D investment. Transfers raise the welfare of all generations, except that of the first resource owner: if resource endowments are taxed at time zero, all successive generations support resource-saving policies for purely selfish reasons.

Motivating Wealth-Constrained Actors

We examine how owners of productive resources (e.g., public enterprises or financial capital) optimally allocate their resources among wealth-constrained operators of unknown ability. Optimal allocations exhibit: (1) shared enterprise profit—the resource owner always shares the operator's profit; (2) dispersed enterprise ownership—resources are widely distributed among operators of varying ability; (3) limited benefits of competition—the owner may not benefit from increased competition for the resource; and, sometimes, (4) diluted incentives for the most capable—more capable operators receive smaller shares of the returns they generate. Implications for privatizations and venture capital arrangements are explored. (JEL D82, D44, D20)