Biblio

Modern cyberattacks are the most powerful disturbance factor for computer networks, as they have a complex and devastating impact. The impact of cyberattacks is primarily aimed at disrupting the performance of computer network protection means. Therefore, managing this defense system in the face of cyberattacks is an important task. The paper examines a technique for constructing an effective control system for a computer network security system operating in real time in the context of cyber attacks. It is supposed that it is built on the basis of constructing a system state space and a stack of control decisions. The probability of finding the security system in certain state at each control step is calculated using a finite Markov chain. The technique makes it possible to predict the number of iterations for managing the security system when exposed to cyber attacks, depending on the segment of the space of its states and the selected number of transitions, as well as automatically generate control decisions. An algorithm has been developed for situational control of a computer network security system in conditions of cyber attacks. The experimental results obtained using the generated dataset demonstrated the high efficiency of the developed technique and the ability to use it to determine the parameters that are most susceptible to abnormal deviations during the impact of cyber attacks.

This paper studies event-triggered output-based security control of nonlinear system under deception attacks obeying a Bernoulli distribution. Firstly, to save system resources of a T-S fuzzy system, an output-based discrete event-triggered mechanism (ETM) is introduced, which excludes Zeno behavior absolutely. Secondly, a closed-loop T-S fuzzy system model is built, which integrates parameters of the nonlinear plant, the ETM, stochastic attacks, fuzzy dynamic output feedback controller and network-induced delays in a unified framework. Thirdly, sufficient conditions for asymptotic stability of the T-S fuzzy sys$łnot$tem are derived, and the design method of a fuzzy output-based security controller is presented. Finally, an example illustrates effectiveness of the proposed method.

The cluster-featured conurbation cyber-physical power system (CPPS) interconnected with tie-lines facing the hazards from catastrophic cascading failures. To achieve better real-time performance, enhance the autonomous ability and improve resilience for the clustered conurbation CPPS, the decentralized cyber structure and the corresponding distributed security control strategy is proposed. Facing failures, the real-time security control is incorporated to mitigate cascading failures. The distributed security control problem is solved reliably based on alternating direction method of multipliers (ADMM). The system overall resilience degradation index(SORDI) adopted reflects the influence of cascading failures on both the topological integrity and operational security. The case study illustrates the decentralized cyber layer and distributed control will decrease the data congestion and enhance the autonomous ability for clusters, thus perform better effectiveness in mitigating the cascading failures, especially in topological perspective. With the proposed distributed security control strategy, curves of SORDI show more characteristics of second-order percolation transition and the cascading failure threshold increase, which is more efficient when the initial failure size is near the threshold values or step-type inflection point. Because of the feature of geological aggregation under cluster-based attack, the efficiency of the cluster-focused distributed security control strategy is more obvious than other nodes attack circumstances.

In a centralized Networked Control System (NCS), all agents share local data with a central processing unit that generates control commands for agents. The use of a communication network between the agents gives NCSs a distinct advantage in efficiency, design cost, and simplicity. However, this benefit comes at the expense of vulnerability to a range of cyber-physical attacks. Recently, novel defense mechanisms to counteract false data injection (FDI) attacks on NCSs have been developed for agents with linear dynamics but have not been thoroughly investigated for NCSs with nonlinear dynamics. This paper proposes an FDI attack mitigation strategy for NCSs composed of agents with nonlinear dynamics under disturbances and measurement noises. The proposed algorithm uses both learning and model-based approaches to estimate agents'states for FDI attack mitigation. A neural network is used to model uncertain dynamics and estimate the effect of FDI attacks. The controller and estimator are designed based on Lyapunov stability analysis. A simulation of robots with Euler-Lagrange dynamics is considered to demonstrate the developed controller's performance to respond to FDI attacks in real-time.

Aiming at the problems of single protection, lack of monitoring and unable to be physically isolated in time under abnormal conditions, an industrial control boundary network security protection method is provided. Realize the real-time monitoring and analysis of the network behavior of the industrial control boundary, realize the in-depth defense of the industrial control boundary, and timely block it in the way of logical link and physical link isolation in case of illegal intrusion, so as to comprehensively improve the protection level of the boundary security of the industrial control system.

This paper develops an adaptive neural network (NN) asymptotic tracking control scheme for nonstrict-feedback switched nonlinear systems with unknown nonlinearities. The NNs are used to dispose the unknown nonlinearities. Different from the published results, the asymptotic convergence character is achieved based on the bound estimation method. By combining some smooth functions with the adaptive backstepping scheme, the asymptotic tracking control strategy is presented. It is proved that the fabricated scheme can guarantee that the system output can asymptotically follow the desired signal, and also that all signals of the entire system are bounded. The validity of the devised scheme is evaluated by a simulation example.

With the reform of the power market(PM), various power applications based on computer networks have also developed. As a network application system supporting the operation of the PM, the technical support system(TSS) of the PM has become increasingly important for its network information security(NIS). The purpose of this article is to study the security protection of computer network information in power systems. This paper proposes an identity authentication algorithm based on digital signatures to verify the legitimacy of system user identities; on the basis of PMI, according to the characteristics of PM access control, a role-based access control model with time and space constraints is proposed, and a role-based access control model is designed. The access control algorithm based on the attribute certificate is used to manage the user's authority. Finally, according to the characteristics of the electricity market data, the data security transmission algorithm is designed and the feasibility is verified. This paper presents the supporting platform for the security test and evaluation of the network information system, and designs the subsystem and its architecture of the security situation assessment (TSSA) and prediction, and then designs the key technologies in this process in detail. This paper implements the subsystem of security situation assessment and prediction, and uses this subsystem to combine with other subsystems in the support platform to perform experiments, and finally adopts multiple manifestations, and the trend of the system's security status the graph is presented to users intuitively. Experimental studies have shown that the residual risks in the power system after implementing risk measures in virtual mode can reduce the risk value of the power system to a fairly low level by implementing only three reinforcement schemes.

This paper presents an observer-based security control scheme for a Cyber-Physical System (CPS). In the considered system, the feedback channel of the CPS may suffer from Denial-of-Service (DoS). To begin with, a time-delayed switching CPS model is constructed according to two different attack situations. And then, based on the switching model, an observer-based controller is designed in the cyber-layer, Meanwhile, the stability of the closed-loop system is analyzed based on H$ınfty$ stability of switching systems in view of Average Dwell Time (ADT). At last, the performance of the proposed security control scheme is illustrated by an numerical example in Simulation.

The model-free adaptive security tracking control (MFASTC) problem of nonlinear networked control systems is explored in this paper with DoS attacks and delays consideration. In order to alleviate the impact of DoS attack and RTT delays on NCSs performance, an attack compensation mechanism and a networked predictive-based delay compensation mechanism are designed, respectively. The data-based designed method need not the dynamic and structure of the system, The MFASTC algorithm is proposed to ensure the output tracking error being bounded in the mean-square sense. Finally, an example is given to illustrate the effectiveness of the new algorithm by a comparison.

This paper focuses on the typical business scenario of intelligent factory, it includes the manufacturing process, carries out hierarchical security protection, forms a full coverage industrial control security protection network, completes multi-means industrial control security direct protection, at the same time, it utilizes big data analysis, dynamically analyzes the network security situation, completes security early warning, realizes indirect protection, and finally builds a self sensing and self-adjusting industrial network security protection system It provides a reliable reference for the development of intelligent manufacturing industry.

In this research work, an advanced automatic multifunctional compact security system technology is developed using wireless networking system. The security system provides smart security and also alerts the user to avoid the critical circumstances in the daily security issues is held. This system provides a smart solution to the variety of different problems via remote control by the software name Cayenne. This software provides the user to control the system using smart mobile or computer from all over the world and needs to be connected via internet. The system provides general security for essential purposes as the Motion detecting system alerts for any kind of movement inside the area where it is installed, the gas detecting system alerts the user for any type of gas leakage inside the room and also clearing the leaking gas by exhaust fan automatically, the fire detection system detects instantly when a slight fire is emerged also warning the user with alarm, the LDR system is for electrical door lock and it can be controlled by Cayenne using mobile or computer and lastly a home light system which can be turned on/off by the user of Cayenne. Raspberry Pi has been used to connect and control all the necessary equipment. The system provides the most essential security for home and also for corporate world and it is very simple, easy to operate, and consumes small space.

The resilient output feedback control of linear networked control (NCS) system with uncertain dynamics in the presence of Gaussian noise is presented under the denial of service (DoS) attacks on communication networks. The DoS attacks on the sensor-to-controller (S-C) and controller- to-actuator (C-A) networks induce random packet losses. The NCS is viewed as a jump linear system, where the linear NCS matrices are a function of induced losses that are considered unknown. A set of novel correlation detectors is introduced to detect packet drops in the network channels using the property of Gaussian noise. By using an augmented system representation, the output feedback Q-learning based control scheme is designed for the jump linear NCS with uncertain dynamics to cope with the changing values of the mean packet losses. Simulation results are included to support the theoretical claims.

With the great development of the information communication technology, power systems have been typical Cyber Physical Systems (CPSs). Although the control function of the grid side is becoming more intelligent, Grid Cyber Physical System (GCPS) brings the risk of potential cyberattacks. In this paper, the impacts of cyber-attacks against GCPS are analyzed based on confusion matrix model firstly, then a double-layer cyber physical collaboration control strategy adjustment methods is proposed considering the status of cyber modules and physical devices infected by cyber-attacks. Finally, the feasibility and effectiveness of the proposed method are verified on the IEEE standard system.

As a new type of complex system, multi delay network in the field of information security undertakes the important responsibility of solving information congestion, balancing network bandwidth and traffic. The problems of data loss, program failure and a large number of system downtime still exist in the conventional multi delay system when dealing with the problem of information jam, which makes the corresponding reliability of the whole system greatly reduced. Based on this, this paper mainly studies and analyzes the stability system and reliability of the corresponding multi delay system in the information security perspective. In this paper, the stability and reliability analysis of multi delay systems based on linear matrix and specific function environment is innovatively proposed. Finally, the sufficient conditions of robust asymptotic stability of multi delay systems are obtained. At the same time, the relevant stability conditions and robust stability conditions of multi delay feedback switched systems are given by simulation. In the experimental part, the corresponding data and conclusions are simulated. The simulation results show that the reliability and stability analysis data of multi delay system proposed in this paper have certain experimental value.

This paper investigates the event-triggered control (ETC) problem for stochastic networked control systems (NCSs) with exogenous disturbances and Denial-of-Service (DoS) attacks. The ETC strategy is proposed to reduce the utilization of network resource while defending the DoS attacks. Based on the introduced ETC strategy, sufficient conditions, which rely on the frequency and duration properties of DoS attacks, are obtained to achieve the stochastic input-to-state stability and Zeno-freeness of the ETC stochastic NCSs. An example of air vehicle system is given to explain the effectiveness of proposed ETC strategy.

The current network security situation of the electric power dispatching and control system is becoming more and more severe. On the basis of the original network security management platform, to increase the collection of network security data information and improve the network security analysis ability, this article proposes the electric power dispatching and control system network security situation awareness analysis module. The perception layer accesses multi-source heterogeneous data sources. Upwards through the top layer, data standardization will be introduced, who realizes data support for security situation analysis, and forms an association mapping with situation awareness elements such as health situation, attack situation, behavior situation, and operation situation. The overall effect is achieving the construction goals of "full control of equipment status, source of security attacks can be traced, operational risks are identifiable, and abnormal behaviors can be found.".

Aiming at the requirements of network access control, illegal outreach control, identity authentication, security monitoring and application system access control of information network, an integrated network access and behavior control model based on security policy is established. In this model, the network access and behavior management control process is implemented through abstract policy configuration, network device and application server, so that management has device-independent abstraction, and management simplification, flexibility and automation are improved. On this basis, a general framework of policy-based access and behavior management control is established. Finally, an example is given to illustrate the method of device connection, data drive and fusion based on policy-based network access and behavior management control.

TV networks are no longer just closed networks. They are increasingly carrying Internet services, integrating and interoperating with home IoT and the Internet. In addition, client devices are becoming intelligent. At the same time, they are facing more security risks. Security incidents such as attacks on TV systems are commonplace, and there are many incidents that cause negative effects. The security protection of TV networks mainly adopts security protection schemes similar to other networks, such as constructing a security perimeter; there are few security researches specifically carried out for client-side devices. This paper focuses on the mainstream architecture of the integration of HFC TV network and the Internet, and conducts a comprehensive security test and analysis for client-side devices including EOC cable bridge gateways and smart TV Set-Top-BoX. Results show that the TV network client devices have severe vulnerabilities such as command injection and system debugging interfaces. Attackers can obtain the system control of TV clients without authorization. In response to the results, we put forward systematic suggestions on the client security protection of smart TV networks in current days.

The security problem of networked control systems (NCSs) suffering denial of service(DoS) attacks with incomplete information is investigated in this paper. Data transmission among different components in NCSs may be blocked due to DoS attacks. We use the concept of security level to describe the degree of security of different components in an NCS. Intrusion detection system (IDS) is used to monitor the invalid data generated by DoS attacks. At each time slot, the defender considers which component to monitor while the attacker considers which place for invasion. A one-shot game between attacker and defender is built and both the complete information case and the incomplete information case are considered. Furthermore, a repeated game model with updating beliefs is also established based on the Bayes' rule. Finally, a numerical example is provided to illustrate the effectiveness of the proposed method.

Modbus TCP/IP protocol is a commonly used protocol in industrial automation control systems, systems responsible for sensitive operations such as gas turbine operation and refinery control. The protocol was designed decades ago with no security features in mind. Denial of service attack and malicious parameter command injection are examples of attacks that can exploit vulnerabilities in industrial control systems that use Modbus/TCP protocol. This paper discusses and explores the use of intrusion detection and prevention systems (IDPS) with deep packet inspection (DPI) capabilities and DPI industrial firewalls that have capability to detect and stop highly specialized attacks hidden deep in the communication flow. The paper has the following objectives: (i) to develop signatures for IDPS for common attacks on Modbus/TCP based network architectures; (ii) to evaluate performance of three IDPS - Snort, Suricata and Bro - in detecting and preventing common attacks on Modbus/TCP based control systems; and (iii) to illustrate and emphasize that the IDPS and industrial firewalls with DPI capabilities are not preventing but only mitigating likelihood of exploitation of Modbus/TCP vulnerabilities in the industrial and automation control systems. The results presented in the paper illustrate that it might be challenging task to achieve requirements on real-time communication in some industrial and automation control systems in case the DPI is implemented because of the latency and jitter introduced by these IDPS and DPI industrial firewall.

With wide application of networked control systems(N CSs), NCSs security have encountered severe challenges. In this paper, we propose a robust event-triggered controller design method under replay attacks, and the control signal on the plant is updated only when the event-triggering condition is satisfied. We develop a general random replay attack model rather than predetermined specific patterns for the occurrences of replay attacks, which allows to obtain random states to replay. We show that the proposed event-triggered control (ETC) scheme, if well designed, can tolerate some consecutive replay attacks, without affecting the corresponding closed-loop system stability and performance. A numerical examples is finally given to illustrate the effectiveness of our method.

The rapid development of the Cloud Computing Technologies (CCTs) has amended the conventional design of resource-constrained Network Control System (NCS) to the powerful and flexible design of Cloud-Based Networked Control System (CB-NCS) by relocating the processing part to the cloud server. This arrangement has produced many internets based exquisite applications. However, this new arrangement has also raised many network security challenges for the cloud-based control system related to cyber-physical part of the system. In the absence of robust verification methodology, an attacker can launch the modification attack in order to destabilize or take control of NCS. It is desirable that there shall be a solution authentication methodology used to verify whether the incoming solutions are coming from the cloud or not. This paper proposes a methodology used for the verification of the receiving solution to the local control system from the cloud using Karush-Kuhn-Tucker (KKT) conditions, which is then applied to actuator after verification and thus ensure the stability in case of modification attack.

In this paper, security of networked control system (NCS) under denial of service (DoS) attack is considered. Different from the existing literatures from the perspective of control systems, this paper considers a novel method of dynamic allocation of network bandwidth for NCS under DoS attack. Firstly, time-constrained DoS attack and its impact on the communication channel of NCS are introduced. Secondly, details for the proposed dynamic bandwidth allocation structure are presented along with an implementation, which is a bandwidth allocation strategy based on error between current state and equilibrium state and available bandwidth. Finally, a numerical example is given to demonstrate the effectiveness of the proposed bandwidth allocation approach.

Modern vehicles in Intelligent Transportation Systems (ITS) can communicate with each other as well as roadside infrastructure units (RSUs) in order to increase transportation efficiency and road safety. For example, there are techniques to alert drivers in advance about traffic incidents and to help them avoid congestion. Threats to these systems, on the other hand, can limit the benefits of these technologies. Securing ITS itself is an important concern in ITS design and implementation. In this paper, we provide a security model of ITS which extends the classic layered network security model with transportation security and information security, and gives a reference for designing ITS architectures. Based on this security model, we also present a classification of ITS threats for defense. Finally a proof-of-concept example with malicious nodes in an ITS system is also given to demonstrate the impact of attacks. We analyzed the threat of malicious nodes and their effects to commuters, like increasing toll fees, travel distances, and travel times etc. Experimental results from simulations based on Veins shows the threats will bring about 43.40% more total toll fees, 39.45% longer travel distances, and 63.10% more travel times.

Analyzing performance of security and stability control system is of great importance for the safe and stable operation of the power grid. Digital dynamic experimental model is built by real time digital simulation (RTDS) in order to research security and stability system of Inner Mongolia in northern 500kV transmission channel. The whole process is closed-loop dynamic real-time simulation. According to power grid network testing technology standard, all kinds of stability control devices need to be tested in a comprehensive system. Focus on the following items: security and stability control strategy, tripping criterion as well as power system low frequency oscillations. Results of the trial indicated that the simulation test platform based on RTDS have the ability of detecting the safe and stable device. It can reflect the action behavior and control characteristics of the safe and stable device accurately. The device can be used in the case of low frequency oscillation of the system.