## 1 Introduction  
Human life has become increasingly dependent on modern information technology. Recent advances in new information and communication networks have led to a shift toward new emerged paradigms, such as smart grids [1], Internet of Things (IoT) [2], cloud computing [3], big data [4], and edge/fog computing [5, 6]. The Internet of things occurs in cases where many devices are connected to the Internet for specific purposes through various techniques. Cloud computing brings a change in the investment mode and resource exploitation. The big data means of analyzing, extracting and processing complex data and large amounts of information. Edge/fog computing is an approach of pushing computing out of centralized systems for better and more scalable performance. Internet technologies have grown exponentially since the inception of the Internet. Currently, a new trend has emerged owing to future networking paradigms, that is, the fourth industrial revolution (Industry 4.0) [7, 8]. The deployment of the IoT in manufacturing plans to provide optimized autonomous systems and self-configuring operations and make them intelligent is referred to as the industrial IoT (IIoT) [9, 10, 11]. Thus, IoT has become an inherent part of our everyday lives because many of its services are provided through billions of intelligent and autonomous objects around the world that are connected and communicate with each other [12]. This revolutionary paradigm creates a new dimension that eliminates the boundaries between the real and virtual worlds. Cyber Physical System (CPS) [13] environments are industrial control and management systems, generally deployed on a large scale, allowing the monitoring, management and administration of critical infrastructures in various fields: health, transport, nuclear, electricity, gas, water, and so forth. Unlike a traditional corporate IT network, the CPS environment allows business systems to be interconnected: industrial equipment, valves, thermal, chemical or medical sensors, command and control system, Human Machine Interface (HMI) rather than desktop computers. Thus, CPS is a set of digital and physical control systems such as (Industrial Control System/Supervisory Control And Data Acquisition (ICS/SCADA) [14; 15; 16], Distributed Control System (DCS) [15], Programmable Logic controller (PLC) [15], Remote Terminal Unit (RTU) [15] and Intelligent Electronic Device (IED) control machines [15], which enables it to perform monitoring and control (locally or remotely) of manufacturing processes, industrial production and distribution in real time. Therefore, Internet and ubiquitous networks have changed the way in which CPS communicate. In this context, IoT success is attributed to the advancements in hardware and communications technologies. The adoption rate of IoT devices will be extremely high as an increasing number of devices are connected to the Internet. As a pioneer in networked systems, Cisco predicts 4.8 ZB of Internet traffic by 2022, and the IP traffic is expected to triple in two years according to Cisco Visual Networking Index [17]. This growth will be driven by increases in numbers of Internet users and connected intelligent devices. Figure 1 shows the growth trend for the numbers of Internet-connected devices. On 19 November 2020, the number of IoT connections (12 billion) exceeded the number of connections without IoT. By 2025, it is expected that there will be more than 30 billion IoT connections, with almost four IoT devices per person on an average [18]. According to IoT Analytics Research, the latest reports about the state of the IoT Q4 2020 and 2021 indicate that the number of IoT devices is predicated to increase much faster than that of non-IoT devices. Some predications expect 30.9 billion connected IoT devices by 2025 owing to the spread of 5G and 6G technologies. As expected, IoT trends suggest that the global number of connected IoT devices will significantly increase in the near future.