A Secure IoT-Fog-Cloud Framework Using Blockchain Based on DAT for Mobile IoT

Internet of Things (IoT) devices are becoming important and familiar products in our everyday lives. Yet, many of these IoT devices have a multitude of vulnerabilities that create a security risk, despite being products that bring a lot of convenience to our lives. Blockchain (BC) technology is gaining popularity these days due to the importance of data security. However, this BC technology is not suitable for IoT devices, because it requires a lot of computing power also IoT devices uses a limited amount of memory and has a lower performing CPU for cost reasons. Also, IoT devices collect a large amount of data and transmit that data every hour and every day to a cloud system to analyze or process the collected data. For this reason, network latency is an important factor in a cloud computing system. In this paper, we propose a secure and distributed IoTFog-Cloud Framework using BC to compensate for the security weaknesses of IoT nodes, the delay aware tree construction (DATC) algorithm that considers the service delay for fog-cloud computing, and the mobility of mobile IoT nodes for BC to deal with the triangular routing problem. To verify this proposed framework, we performed security analysis and experiments for the effectiveness of the algorithm through simulation and confirmed that the overall service delay was reduced by choosing the minimum delay path by the DATC algorithm.