I. Introduction
Over the last few years, with the rapid advances of sensing technologies and wireless communications, industrial Internet of Things (IoT) has made a great progress [1]. Industrial IoT is created by embedding smart electronics into production systems via a dynamic global information network. It is improving the effectiveness and efficiency of modern industrial production and applications. For example, industrial IoT enables condition monitoring, structural health monitoring, remote diagnosis, and remote control of production systems in real time. Furthermore, industrial IoT makes smart factories become possible for dynamically organizing and optimizing production processes [2].