FOCUS: A fog computing-based security system for the Internet of Things

As the Internet of Things (IoT) continues to grow, there arises concerns and challenges with regard to the security and privacy of the IoT. Cyber attacks such as man-in-the-middle and distributed denial of service (DDoS) are typical threats to the IoT. In this paper, we propose a FOg CompUting-based Security (FOCUS) system to protect the IoT against malware cyber attacks. The proposed FOCUS system leverages the virtual private network (VPN) to secure the communication channels to the IoT devices. In addition, FOCUS adopts a challenge-response authentication to protect the VPN server against potential DDoS attacks, which can further enhance the security of the IoT system. Such a double protection scheme is effective in mitigating various malicious attacks and can provide a high standard security for the IoT system. Furthermore, FOCUS is implemented in fog computing that is close to the end users, thus achieving a fast response and an efficient network consumption. We demonstrate FOCUS in a proof-of-concept prototype, and conduct experiments to evaluate its performance. The results show that FOCUS can effectively filter out malicious attacks with a low response time and a small amount of network bandwidth consumption.