Smart cities aim to provide smart governance with the emphasis on gaining high transparency and trust in public services and enabling citizen participation in decision making processes.This means on the one hand data generated from urban transactions need to be open and trustworthy. On the other hand, security and privacy of public data needs to be handled at different administrative and geographical levels. In this paper, we investigate the pivotal role of blockchain in providing privacy, self-verification, authentication, and authorization of participatory transactions in open governance. We also investigate up to what extent edge computing can contribute toward management of permissioned sharing at specific administrative levels and enhance privacy and provide an economic approach for resource utilization in a distributed environment. We introduce a novel architecture that is based on distributed hybrid ledger and edge computing model. The architecture provides refined and secure management of data generated and processed in different geographical and administrative units of a city.We implemented a proof of concept of the architecture and applied it on a carefully designed use case, ie, citizen participation in administrative decisions through consensus. This use case highlights the need to keep and process citizen participation data at local level by deploying district chaincodes and only share consensus results through permissioned chaincodes. The results reveal that proposed architecture is scalable and provide secure and privacy protected environment for citizen participatory applications. Our performance test results are promising and show that under control conditions, the average registration time for a citizen transaction is about 42 ms, whilst the validation and result compilation of 100 concurrent citizens' transactions took about 2.4 seconds.
INTRODUCTIONSmart cities are becoming prevalent in urban areas to deal with different societal challenges such as sustainable transport, energy, greenhouse gas emissions and monitoring, public health and quality of life, economic and job growth, etc. 1,2 The ubiquitous nature of smart IT-based solutions provides new services to citizens. As a result, it has become a source of new information for city administrations for smart open governance, based on which city development plans are proposed and strategic decisions are made. Such a smart open governance approach aims to engage with citizens through innovative approaches and deliver highly transparent and trustable public services. 3 The involvement of citizen in city planning through consultation meetings, opinions, polls, and call-for-comments on online proposals is referred as citizen engagement or participation, eg, smarticipate project. 4 This enables city administrators to get to know actual needs of the local community, co-create and transform the city infrastructure and services around citizens' needs and requirements. Berntzen and Johannessen 5 highlighted importance of citizen's role in the participat...