Security Control Method Research Articles

Adaptive event-triggered security control for networked teleoperation systems.

An adaptive event-triggered security control method is proposed for networked robotic teleoperation systems subject to time-varying delays and false data injection (FDI) attacks. An event-triggered scheme is designed via the position and velocity signals of the master and slave robots, where the triggering thresholds can change adaptively with the system states. The position and velocity triggered signals and the feedback error between the operator and the environment forces are utilized to detect whether the transmitted signals suffered from FDI attacks. Then, a switching controller is designed, which is able to adopt the corresponding control strategy according to the corresponding detection result. The stability of the system and the convergence of the tracking errors are proved through Lyapunov functions, and the proposed method is validated through practical experiments. The proposed method is able to adaptively adjust the triggering frequency and effectively reduce the transmitted data, thus saving the network resources. Meanwhile, it can ensure the stability of networked teleoperation systems under time-varying delays and FDI attacks, as well as the position and force tracking performance.

Secure intermittent impulsive consensus control for fractional-order multiagent systems under denial-of-service and deception attacks

This article addresses the secure consensus problem of fractional-order multiagent systems (FOMASs) under denial-of-service (DoS) and deception attacks in the intermittent impulsive control framework. Unlike previous cyber attack models, the multiple attacks are considered, which the agent-to-agent communication channels and the controller-to-actuator channels are randomly subjected to deception and DoS attacks, respectively. Some random variables that follow the Bernoulli distribution are proposed, which are related to the communication channels between adjacent agents to describe deceptive attack behavior. To reduce control costs and resist cyber attacks, a novel intermittent impulsive control strategy is designed to make the FOMASs achieve consensus faster, when DoS attacks are sleeping. The designed intermittent impulsive control includes the advantages of discrete sampling control and intermittent control, which means that it can reduce the injection of erroneous data by constraining the frequency of information transmission. Furthermore, some sufficient criteria including the parameters of multiple attacks are yielded to ensure mean-square quasi-consensus of FOMASs. Finally, two examples are provided to validate the rationality for the presented security control method in this study from the perspective of numerical simulation experiments.

Event-Triggered Data-Driven Security Formation Control for Quadrotors Under Denial-of-Service Attacks and Communication Faults.

In this article, the security formation control problem is investigated for underactuated quadrotors involving nonlinear coupled dynamics, subject to denial-of-service (DoS) attacks and uncertain communication faults. A security formation control method is proposed, including a distributed resilient observer and a hierarchical data-driven controller. The observer with an adaptive event-triggered mechanism is developed to restrain the influence of DoS and communication faults on interaction information among quadrotors, and Zeno behavior of all observers can be avoided. The optimal control laws are learned iteratively based on observation data and system data by utilizing reinforcement learning without knowledge of system dynamics. The stability of the constructed closed-loop control system is proven, and sufficient conditions are established for the unreliable network. Simulation results demonstrate the advantages of the proposed security control method.

Retracted: Sensor Network Security Risk Prediction and Control Method Based on Big Data Analysis

Retracted: Sensor Network Security Risk Prediction and Control Method Based on Big Data Analysis

Resilient Distributed Event-Triggered Platooning Control of Connected Vehicles Under Denial-of-Service Attacks

The security control of a vehicle platoon depends on the network topology and communication quality. Denial of service (DoS) attacks force vehicle formations to destabilize by disrupting digital communications between vehicles. To this end, this paper develops a resilient distributed event-triggered security control strategy to resist the malicious impact of DoS attacks on connected vehicles. By designing a distributed event-triggered mechanism based on sampled data, the controller updating frequency is reduced, thereby promoting utilization rate of network resources. Since the end of the attack is not the sampling instant, this may prolong the duration of the attack. To overcome this problem, a switched sampled-data scheme is proposed to ensure that the control signal acts on the system immediately when the attack ends. Then, a switched system model with artificial delay is established to capture the sampling period, event triggering mechanism and DoS attack purpose. With the analysis methods of switched system and time-delay system, sufficient conditions are obtained to guarantee the same safe distance and speed between vehicles, so that the connected vehicle system can achieve the desired tracking effect. A co-design approach is given with respect to controller gains and triggering parameter. Finally, simulation and experimental studies are provided to demonstrate the effectiveness of the proposed security control method.

Probabilistic Security-Constrained Preventive Control under Forecast Uncertainties Including Volt/Var Constraints

The continuous increase in generation from renewable energy sources, marked by correlated forecast uncertainties, requires specific methodologies to support power system operators in security management. This paper proposes a probabilistic preventive control to ensure N-1 security in presence of correlated uncertainties of renewable sources and loads. By adopting a decoupled linear formulation of the AC load flow equations, the preventive control is decomposed into two subsequent linear programming problems, the former concerning the active power and the latter the voltage/reactive power-related issues. In particular, in the active control problem, the algorithm combines Third Order Polynomial Normal Transformation, Point Estimate Method, and Cornish–Fisher expansion to model the forecast uncertainties and characterize the chance constraints in the problem. The goal is to find the optimal phase shifting transformer tap setting, conventional generation redispatching, and renewable curtailment at the minimum cost to assure the probabilistic fulfillment of N and N-1 security constraints on branch active power flows. The second stage solves another linear programming problem, which aims to minimize the adjustments to generators’ set-point voltages to avoid violations at node voltages and branch-rated limits due to reactive power flows while meeting generator reactive power constraints. Simulations performed on an IEEE test system demonstrate the effectiveness of the proposed security control method in limiting the probability of violating security limits in N and N-1 state, including voltage/reactive power constraints, in presence of correlated uncertainties.

Security control of internet of things node access method using blockchain technology

Due to the problems of high false positive rate and low abnormal detection rate in the current IoT node access security control method, based on this, this paper designs a new IoT node access security control method. Firstly, the information security sharing structure is designed, the data collection work is completed, and the data is preprocessed. The preprocessed data is then shared and backed up through blockchain technology. Finally, take the login time, number of logins, login time, number of query results, query time and number of queries as the access constraints, and complete the security control of the access to the IoT nodes by correctly setting the access authorization conditions. The experimental results show that the false positive rate of IoT access behavior detection is always lower than 0.3%, the detection rate of IoT access anomaly is low, the detection sensitivity is higher than 80%, and the node encryption complexity is low, which has certain application value.

Integrated security control method for industrial cyber-physical system with attack and fault

Integrated security control method for industrial cyber-physical system with attack and fault

Observer-based defense control for networked Takagi-Sugeno fuzzy systems against asynchronous DoS attacks

This article investigates the defense control problem for sampled-data Takagi-Sugeno (T-S) fuzzy systems with multiple transmission channels against asynchronous denial-of-service (DoS) attacks. Firstly, a new switching security control method is proposed to tolerate the asynchronous DoS attacks that act independently on each channel. Then, based on switching strategy, the resulting augmented sampled-data system can be converted into new switched systems including several stable subsystems and one open-loop subsystem. Besides, by applying the piecewise Lyapunov-Krasovskii (L-K) function method, membership functions (MFs) dependent sufficient conditions are derived to ensure the exponential stability of newly constructed switching systems. Moreover, quantitative relations among the sampling period, the exponential decay rate, and the rate of all channels being fully attacked and not being completely attacked are established. Finally, simulation examples show the effectiveness of the developed defense control approach.

Distributed security secondary control for cyber-physical microgrids systems under network DoS attacks

This paper considers the frequency regulation and power-sharing problems for cyber-physical microgrids (MGs) under network denial-of-service (DoS) attacks and time-varying communication delays. Compared to conventional distributed controllers based on a system model with ideal communication, a distributed security control protocol is designed. Benefiting from the developed security control method, the adverse effects of network DoS attacks and communication delays can be resisted. Then, a sufficient condition, which is used to achieve the achieve frequency restoration and power-sharing, is established according to the frequency and duration of DoS attacks. By using the average dwell time method and the Lyapunov stability theory, it is theoretically proved that the proposed control scheme can guarantee the stability of the overall AC microgrid system. In order to illustrate the proposed scheme, simulation studies are carried out based on an islanded AC microgrid system with four distributed generators (DGs) built in the simulation. The results do show its effectiveness and also verify the established theoretical results.

Cooperative control for cyber–physical multi-agent networked control systems with unknown false data-injection and replay cyber-attacks

The paper discusses the cooperative tracking problem of partially known cyber–physical multi-agent networked systems. In this system, there exist two cascaded chances for cyber-attacks. The local agent is of networked system type that is subjected to unknown false data-injection and replay cyber-attacks that are dissimilar in the sensor-controller and the controller-actuator network parts. The communication between any two agents, if they are connected, is accomplished via a communication network that is subjected to false data-injection cyber-attacks. The problem of the existing two cascaded chances for cyber-attacks is solved in three steps. First, with partially known system parameters and unknown false data-injection and replay cyber-attacks, the state estimates of all the local followers are evaluated by designing local adaptive observers. Second, a new technique is designed to compensate for the unmatched terms that result from the use of local adaptive observers. After that, distributed adaptive leader–follower security controllers are proposed based on the local estimated information in addition to the infected arrived information from the neighbors. Meanwhile, it is verified that the suggested security control method guarantees that all states of the followers under the considered cyber-attacks follow the given leader asymptotically. The efficacy of the developed adaptive leader–follower security controllers is verified via an illustrative example.

Security Control Method of Loading for Surcharge Preloading Based on the Stress Path

All the time, security control method of loading is an important research part in the surcharge preloading, which is directly related to safety of the construction process. Starting from the stress path, discussing the variation of excess pore water pressure and relationship between stress path and security, and bringing forward the control method with a safety factor Fs based on the stress path. By measuring the change of excess pore water pressure, the control method with a safety factor Fs can reflect quantitatively the security status of soil and achieve the purpose of the process control, finally the security control method including the safety factor of loading and speed control is put forward to monitor construction safety. The safety factor of loading Fs is verified and back analyzed with the finite-element software, getting the correction factor from 0.90 to 1.20.

Security-control methods for statistical databases: a comparative study

This paper considers the problem of providing security to statistical databases against disclosure of confidential information. Security-control methods suggested in the literature are classified into four general approaches: conceptual, query restriction, data perturbation, and output perturbation. Criteria for evaluating the performance of the various security-control methods are identified. Security-control methods that are based on each of the four approaches are discussed, together with their performance with respect to the identified evaluation criteria. A detailed comparative analysis of the most promising methods for protecting dynamic-online statistical databases is also presented. To date no single security-control method prevents both exact and partial disclosures. There are, however, a few perturbation-based methods that prevent exact disclosure and enable the database administrator to exercise "statistical disclosure control." Some of these methods, however introduce bias into query responses or suffer from the 0/1 query-set-size problem (i.e., partial disclosure is possible in case of null query set or a query set of size 1). We recommend directing future research efforts toward developing new methods that prevent exact disclosure and provide statistical-disclosure control, while at the same time do not suffer from the bias problem and the 0/1 query-set-size problem. Furthermore, efforts directed toward developing a bias-correction mechanism and solving the general problem of small query-set-size would help salvage a few of the current perturbation-based methods.