A survey of blockchain applications in sustainable and smart cities

Global urbanization has vastly enhanced the quality of people's lives in various domains. Nevertheless, the global rise in urban dwellers is often accompanied by additional difficulties and challenges such as traffic jams, air pollution, greenhouse gas emissions, and waste production. The term 'Smart City' is introduced to address these challenges by pushing residents to concentrate on the innovative solutions for economic growth of their cities as well as enhancing people's standard of living. The distributed ledger technology, also known as Blockchain, is best known for its instrumental role in forming the cryptocurrency space (e.g. Bitcoin and Ethereum). Due to features that include decentralization, transparency, democracy, security, and immutability; the deployment of Blockchain technologies in smart cities drastically improves data integrity, openness in city maintenance, and fosters the execution of reliable, transparent, safe, and democratized services and applications. In this survey, we perform an exhaustive study of research works that include the use of Blockchain technologies for smart city services and applications. First, we will examine the brief history of smart cities and Blockchain. We will then delve into the various ways that Blockchain technologies can be integrated into various smart city domains that include smart governance, smart transportation, smart grids, smart management, trade & finance, smart healthcare, smart home, e-commerce, and others that have a scope of development. Finally, this paper will provide areas of interest where Blockchain can be analyzed further to promote the development of smart cities application and services using Blockchain.