Issues and Challenges associated with Blockchain in Smart Cities

Blockchain technology now has applications in many areas, such as cryptocurrencies and smart contracts. For example, in an IoT system, sensors from different devices transfer data collected in cloud computing on a central server. The issues that arise relate to security and privacy matters that occur mainly due to difficulties in upgrading the software of millions of smart devices and the management of servers in the cloud by other third-party companies. By enabling the blockchain, various security options are offered by storing transactions in a decentralized and transparent system. However, a lot of effort is needed to integrate blockchain systems and their application in smart cities. In this work, we review how blockchain systems can be integrated into smart cities.