# Edge Computing for IoT-Enabled Smart Grid: The Future of Energy
## 4 EC-IoT SCADA Application  
In recent years, IoT has been applied in various areas of energy management systems, including power generation systems, distribution systems, advanced metering systems, intelligent energy management systems for smart homes, smart buildings and smart cities, etc. [2,4]. Combining edge computing and IoT provides huge possibilities for optimizing and managing the energy transmission systems. In this section, we discuss one of the important applications of smart grids based on IoT and EC, the well-known SCADA (Supervisory Control and Data Acquisition) system [48]. The detailed information is presented as follows. The SCADA system collects data and information from sensors, cameras and IoT devices from the power grid system and supervises automation procedures to monitor and control and regulate different system parameters for the optimal energy grids. The SCADA system is formed with the integration of computing and IoT technologies [49]. The SCADA architecture consists of three layers, presented in Figure 5.  
The Things layer consists of terminal devices such as sensors, IoT devices, actuators and appliances. These IoT devices are interconnected with each other based on different efficient communication technologies, including Wi-Fi, Bluetooth, ZigBee, NB-IoT, LTE-A, NFC, etc. To enhance the ability of IoT-enabled SCADA systems, the EC layer is added to its architecture. In this model, the EC layer includes various network devices such as gateway, access points, switches, routers, and local SCADA servers to analyze, process, compute and storage [50]. The SCADA system shortens the distance between the database and terminal devices, reducing service response time. On the other hand, it brings the capabilities of the cloud closer to the user and realizes real-time SGs. The cloud layer consists of cloud SCADA data servers that are responsible for analytics and aggregating whole statistics and obtained information from the edge layer of SCADA. Thanks to these results, an autonomous process or electric personnel making-decision to monitor, control, and adjust parameters to optimize SGs. The overall architecture of the SCADA system is presented in Figure 5.  
Although there are many advantages, SCADA systems have still existed some limitations in aspects of cybersecurity. At the Things layer, attacks can focus on IoT and PLC devices to collect or fake information. Furthermore, SCADA applications often operate on Windows operating systems, and attacks are possibly employed through vulnerabilities of Windows operating systems [51]. On the other hand, with the limited capacities of IoT devices, it is infeasible to implement complex security and encryption protocols. Therefore, lightweight encryption algorithms need to be researched. In [52], the authors have introduced a multi-layerlightweight cryptography architecture that relies on both symmetric and asymmetric key cryptographic algorithms for real-time SCADA systems. At the network layer, the variety of communication protocols led to facing a series of potential cyberattack risks of SCADA systems. In [53], the authors have presented a series of communication protocols used in SCADA systems and attack types and solutions, respectively. On the one hand, adding the edge layer to the traditional SCADA architecture enables the realization of the real-time computing concept. On the other hand, EC systems require network expansion, including IoT devices and edge servers relying on autonomous distributed computing. This leads to the cybersecurity threats. DoS attacks can target edge computing centers, as presented in [54]. The above analyses have shown that the security issue of EC-based SCADA systems needs further research. The cloud layer provides powerful computing and storage capabilities for cloud-based SCADA systems. However, the authors [55] have presented a variety of security issues in the cloud, such as attacks on user interfaces through the SICADD-MTU Web portal or communication channels to the RTUs.