ABSTRACT
Information and communication technology (ICT) has facilitated the revolution of smart cities by advancing information management and communication technologies which in turn enhanced our lives. These great advancements were possible by deploying an enormous number of smart objects everywhere (e.g., smart mobile phones and watches, home appliances, autonomous vehicles) equipped with sensors able to collect and process information and send it to remote servers, mainly in the cloud. The increase in the number of these devices, as well as the amount of processed data, have become a new challenge and difficult for the centralised cloud system to manage. Fog and edge paradigms have emerged as potential solutions to cope with cloud limitation. The concept behind brings part of the computation closer to end-user devices. To this end, these technologies face serious issues in terms of security, privacy, and integrity of collected data. Indeed, in Internet of Things (IoT), diverse types of data are exchanges, some of which are sensitive and confidential and require a high level of security and privacy. Moreover, traditional security solutions may not be good enough in the near future which will require investigating more advanced and sophisticated solutions such as blockchain. Blockchain is used to solve many security issues while dealing with databases and stored data. The alliance among IoT, fog computing, and blockchain leverages the advantages of each of these technologies; however, it may face some other challenges such as scalability. In this chapter, we comprehensively overview these technologies, their advantages and disadvantages, the challenges arising from their integration, and some solutions on how to achieve secure storage in fog computing using blockchain.
