# Securing SCADA Energy Management System under DDs Attacks Using Token Verification Approach
## 1 Introduction  
The Industrial Internet of Things (IIoT) or Industry 4.0 has led to constant exploration and development in new industrial control and monitoring, industrial automation, working service process, data analysis of assembly lines, and new commercial models. There are many successful and actual examples available in relevant studies, such as adopting the Supervisory Control and Data Acquisition (SCADA) [1] system and the Programmable Logic Controller (PLC) [2] to establish a reservoir control system [3]. Hence, the Industrial Control System (ICS) [4] is perceived as playing a critical role in technological transitions and national security. Due to the special features of IIoT, damages caused by information security threats can easily go beyond the internet and cause substantial destruction. In the communication platform of the Industrial Internet of Things, Local Operating Networks (LON) is a common automation and monitoring network architecture classical solution. In addition, in the media access control (MAC) layer, how to avoid conflicts and cause unfair sharing of network bandwidth between devices (communication nodes) is an important issue. P-persistent CSMA (Carrier Sense Multiple Access) scheme is usually easy to cause possible bandwidth allocation unfair problem between competing nodes. The authors of [5] analyzed that in most network traffic scenarios, unfairness is the shortcoming ofpredictive p-persistent CSMA operations. It also proves that the average bandwidth available to a node is a linear function of its degradation state and does not depend on the degradation state of other sites. Aiming at the unfairness of random access in the Industrial Internet of Things, the authors of [6] further studied the deviation of the site from the defined competition mechanism in CSMA/CA (Collision Avoidance), and used Bianchi model to estimate that this deviation affected network throughput. It shows that the fairness of the network is seriously affected. Moreover, the dynamic average discounted payoff mechanism of game theory is used to solve the problem of network throughput allocation. It can be seen that the quality of service (QoS) of the network plays an important role in the industrial Internet of Things. When the nodes generate a large amount of data, the media access control (MAC) layer protocol does not perform well in terms of fairness and throughput. Because the MAC layer does not have the capacity to provide QoS for priority or forwarding flows. Therefore, it is not easy to be detected when the device is attacked. The authors of [7] proposed a QoS-IoT architecture and developed an adaptive contention window (CW) algorithm for evaluation of the effectiveness of fairness, throughput and utilization in medium access control. In addition, the attack detection, fairness, throughput and buffer utilization are evaluated through the simulation of Sybil attack. The experiments in [7] show that QoS-IoT has significant performance.In addition, in QoS, attacks on the application layer of the network architecture are also quite common.Among the threats to information security, DoS is an attack specifically designed to paralyze a certain network, device, or source. During one kind of DoS attack, DDoS uses a number of intrusive devices, namely, botnets, to attack a target system and paralyze its network or processor through an intensive operation; for example, the botnet Mirai [8] has paralyzed many famous networks and online services. Though this virus did not impact the industrial sector, it revealed how DDoS attacks could cause possible devastating consequences. Moreover, as the source code of this virus has been published online and the DDoS service is emerging, many other attacks targeting IoT and other basic IoT architectures are expected to be seen in the future. By using the same token, an intruded ICS system would eventually become a member of the botnets, which could be used as a tool for hackers to attack other enterprises.