Control Channel Research Articles

Control of Nonlinear Systems with Input Delay

An algorithm for control of nonlinear systems with sector nonlinearity and a constant known time-delay in the control channel is proposed. To design the control law, a predictor of the controlled variable by the time-delay value is used. Unlike the predictor of O. Smith, the predictor under consideration can be applied to unstable systems, and differently from the predictor of A. Manitius and A. Olbrot, the proposed predictor does not contain an integral component, which requires accurate implementation to predict the regulated signal. Next, based on the proposed predictors, subpredictors are built, which are a sequential connection of a series of similar predictors, but with a shorter time-delay. As a result, the use of a subpredictor allows one to control plants with a larger time-delay, which is reflected in the closed-loop system, where the time-delay is as many times less than the original one as the number of predictors used in the prediction scheme of the controlled variable. Using the method of Lyapunov-Krasovsky functionals and the S-procedure, sufficient conditions for the stability of the closed-loop system are obtained in the form of solvability of linear matrix inequalities. The asymptotic convergence to zero of the state vector and the uniformly boundedness of all signals in the closed-loop system are proven. It is shown that the resulting linear matrix inequalities depend on the parameters of the plant, sector boundaries for nonlinearity and time-delay, which makes it possible to calculate their upper values when the closed-loop system remains stable. These problems may be relevant when calculating the upper value of the sector of the nonlinearity under consideration or the upper value of the time-delay during remote control. The results of computer modeling are presented, which illustrate the efficiency of the proposed approaches and demonstrate an increase in the possible time-delay in the system when using a subpredictor scheme. The example shows that when using a serial connection of two subpredictors instead of one, the maximum time-delay in the control channel can be doubled. Moreover, in contrast to the predictor of A. Manitius and A. Olbrot, the subpredictor scheme is simple due to the lack of implementation of the integral component.

Research of Options for Constructing Information Management Systems Based on Network Models of Queuing Systems

The use of information management systems (IMSs) for the management of technical facilities is currently one of the directions for further improvement and increase in the effectiveness of the use of technical facilities in solving their target tasks. The existing modern IMSs are a set of hardware and software tools designed for collecting, processing and storing information and management. In the presence of a large amount of information and contradictory factors affecting the quality of management, making informed and timely decisions in the management process is impossible without the use of IMSs. The IMSs currently being developed are, for the most part, specialized systems and are designed to solve specific tasks. In this regard, the development and design of IMSs should be carried out taking into account the relationship with the target indicators and features of the management facilities, the results of a comprehensive analysis of information about the IMS elements in the process of functioning, and structural and algorithmic parameters that affect performance indicators. The use of mathematical models for the study of options for the construction of an IMS is the basis for the design and development of devices and subsystems of an IMS. The IMS models currently being developed make it possible to conduct research for single-stage management processes with the presence of similar service facilities in the system. At the same time, modern technical facilities and control systems are complex complexes with cyclically repeating control processes of various types of means. As a rule, such complexes have a set of parallel operating devices (control channels) that provide control of different types of objects at various stages of information processing. In this case, the structure of the IMS must be represented as a multiphase multichannel technical system in which the process of simultaneous management of several objects of various types takes place. In this regard, the purpose of the article is to develop a mathematical model of an IMS with two phases of management and the presence of an arbitrary number of serviced different types of management facilities. The basis of the model is a multiphase CFR network model with a limited waiting time for an application in the service queue. The study on the model allows choosing an option for building an IMS, in particular, choosing the optimal number of control channels for various types of objects according to the criterion of optimality and restrictions on the cost and time of management. An algorithm for selecting an option for building an IMS has been developed, and an example of calculating the number of control channels for managing three types of objects is given.

Role of Point Defects and Ion Intercalation in Two-Dimensional Multilayer Transition Metal Dichalcogenide Memristors.

Two-dimensional materials, in particular transition metal dichalcogenides (TMDs), have attracted a nascent interest in the implementation of memristive architectures. In addition to being functionally similar to synapses, their nanoscale footprint promises to achieve the high density of a biological neural network in the context of neuromorphic computing. However, in order to advance from the current exploratory phase and reach reliable and sound memristive performances, an understanding of the underlying physical mechanisms in TMD memristors seems imperative. Despite the distinctive transport medium inherent to multilayer TMDs, the memristance is routinely attributed to defects or metal atoms present in the system, with their precise contribution remaining elusive. Specifically, the role of intrinsic point defects in the formation of conductive channels, although shown for monolayer TMDs, is not conclusively studied for multilayer samples. In this work, using density functional theory (DFT) and nonequilibrium Green's function (NEGF) formalism, a systematic study is carried out to analyze the impact that defects and metal atoms produce on the out-of-plane conductivity of multilayer TMDs. MoS2, a representative of the 2H structural configuration, and PtS2, a representative of the 1T structure, the most common crystal arrangements among TMDs, are used for this analysis. It is found that the intrinsic sulfur vacancies, which are the dominant defects present in both TMDs, appear to be insufficient in causing resistive switching on the application of an external bias. The claim that the intrinsic point defects on their own can realize a valence change memory-type device by providing a controllable conductive channel through the van der Waals structure seems, according to our study, improbable. The presence of metallic atoms is demonstrated to be essential to trigger the memristive mechanism, emphasizing the proper choice of a metal electrode as being critical in the fabrication and optimization of memristors using TMDs.

Bioremediation of nitrate in agricultural drainage ditches: Impacts of low-grade weirs on microbiomes and nitrogen cycle gene abundance

Artificial drainage is essential for the success of modern agriculture, but it can also accelerate the movement of nutrients, especially nitrate, from soil to surrounding and downstream water bodies. Removal of nitrate from agricultural drainage by using controlled drainage systems, such as ditches installed with low-grade weirs, has been shown to help reduce nutrient loading into watersheds. However, the effect of low-grade weirs varies greatly, likely due to the differences in climate, system designs (e.g., hydraulic characteristics), and the resulting variation in microbial structures and functions in the ditch. In this study, we analyzed the temporal and spatial dynamics of microbiomes in a paired ditch system with weir-installed and uninstalled (control) channels over two years by using the 16S rRNA gene amplicon sequencing and the high-throughput quantitative PCR targeting various N cycle-associated genes [the Nitrogen Cycle Evaluation (NiCE) chip]. The installation of the low-grade weir had a significant impact on the microbiome structure and the distribution of denitrifiers. Microbiome structures also differed significantly between the ditch inlets and the outlets. Denitrification functional genes were more abundant in the inlets than in the other locations and in the channel installed with a low-grade weir. Additionally, oxygenic denitrifiers that utilize nitric oxide dismutase (nod) to produce N2 and O2 gases from nitric oxide were detected in the ditch channels, suggesting the occurrence of nitrate removal process that bypasses the production of nitrous oxide (N2O). The ditch microbiomes sampled during high-flow seasons (i.e., spring and fall) exhibited greater similarity to each other than microbiomes sampled during low-flow seasons (i.e., summer). Taken together, this study indicates that the low-grade weirs have the potential to foster a more favorable environment for denitrifiers, resulting in an increase in the abundance of denitrification functional genes. These findings could offer valuable insights into system management and optimization strategies.

КЕРУВАННЯ ДИНАМІКОЮ ІМПУЛЬСНОГО ПЕРЕТВОРЮВАЧА З М’ЯКИМ ПЕРЕМИКАННЯМ, ЩО ПРАЦЮЄ НА ДУГОВЕ НАВАНТАЖЕННЯ

Issues of design and research of energy-efficient and reliable semiconductor DC voltage converters for wide application in power supply devices of arc plasmatrons used in plasma metal cutting installations are considered. An estimated structural dynamic model of a soft-switching DC converter with a closed-loop control system combining the power part and the control system, intended for use as part of the latter as a digital module, was built. A technique is proposed and methods of controlling the converter are found, which provide the specified duration of transient processes, the permissible value of load current pulsations in a quasi-steady mode and the astatism of the output current, which confirms the correctness of the proposed technique. A prototype of a pulse stabilizer with digital control was made. The results of experimental studies of the sample confirm the effectiveness of the developed control device, namely the achievement of the specified duration of transient processes caused by a step change in the load current, close to 10-12 periods of conversion and astatism of the output current. It is shown that the application of a pulse stabilizer, in which a digital control loop is used, has significant advantages compared to analog options and has the advantages of a strategic plan. The use of combined control allows you to significantly reduce the requirements for the overall gain of the main control channel, which greatly facilitates the choice of sequential digital correction. Research results may be of interest to specialists in the field of power electronics, power supply systems of autonomous objects and control systems. References 14, figures 11. Key words: automatic control system, digital controller, external disturbance, plasma, robustness, optimization.

Soft X-ray spectromicroscopic proof of a reversible oxidation/reduction of microbial biofilm structures using a novel microfluidic in situ electrochemical device

In situ electrochemistry on micron and submicron-sized individual particles and thin layers is a valuable, emerging tool for process understanding and optimization in a variety of scientific and technological fields such as material science, process technology, analytical chemistry, and environmental sciences. Electrochemical characterization and manipulation coupled with soft X-ray spectromicroscopy helps identify, quantify, and optimize processes in complex systems such as those with high heterogeneity in the spatial and/or temporal domain. Here we present a novel platform optimized for in situ electrochemistry with variable liquid electrolyte flow in soft X-ray scanning transmission X-ray microscopes (STXM). With four channels for fluid control and a modular design, it is suited for a wealth of experimental conditions. We demonstrate its capabilities by proving the reversible oxidation and reduction of individual microbial biofilm structures formed by microaerophilic Fe(II)-oxidizing bacteria, also known as twisted stalks. We show spectromicroscopically the heterogeneity of the redox activity on the submicron scale. Examples are also provided of electrochemical modification of liquid electrolyte species (Fe(II) and Fe(III) cyanides), and in situ studies of electrodeposited copper nanoparticles as CO2 reduction electrocatalysts under reaction conditions.

METHOD OF RECOGNITION OF FPV-UAV RADIO SIGNALS FORMED ACCORDING TO CROSSFIRE AND EXPRESSLRS STANDARDS

Unmanned aerial vehicles (UAVs) with the First Person View (FPV) system are the most common type of attack UAVs used at the tactical level by the armed forces of the russian federation. Timely detection of facts of their using by the enemy and countering them are important tasks solved by units of the Ukrainian Defense Forces. An effective countermeasure way for FPV-UAVs is to create interference in their radio control channels frequency bands. To increase the radio suppression range, it is necessary to use interference matched in frequency and structure, the necessary condition for the formation of which is the presence of a priori information about the structure of the radio signal. Analysis of the available information on the construction of enemy FPV-UAVs shows that their radio control and telemetry channels are usually combined, have time division multiple access, the signals are formed according to CrossFire and ExpressLRS standards and have fixed sets of parameter values that can be used as features in recognition. The proposed FPV-UAV radio signal recognition technique is based on decision tree and minimum metric methods and uses a priori information on frequency, time and modulation parameters of radio signals. The combination of the two decision-making methods made it possible to reduce the computational complexity by eliminating operations for determining the parameters of radio signals that do not correspond to the decisions taken at the previous stages, and provides the possibility of adding new time parameters without changing the developed recognition technique. The method consists of a sequence of operations for estimation radio signal parameters, comparing them with known values, making decisions about the type of standard and command- telemetry radio line operation mode. Only one fragment with a duration of one frequency element is sufficient to recognize the FPV-UAV radio signal, which reduces the technical requirements for detection means in which the method can be used.

Accurate and efficient elephant-flow classification based on co-trained models in evolved software-defined networks

Accurate early classification of elephant flows (elephants) is important for network management and resource optimization. Elephant models, mainly based on the byte count of flows, can always achieve high accuracy, but not in a time-efficient manner. The time efficiency becomes even worse when the flows to be classified are sampled by flow entry timeout over Software-Defined Networks (SDNs) to achieve a better resource efficiency. This paper addresses this situation by combining co-training and Reinforcement Learning (RL) to enable a closed-loop classification approach that divides the entire classification process into episodes, each involving two elephant models. One predicts elephants and is retrained by a selection of flows automatically labeled online by the other. RL is used to formulate a reward function that estimates the values of the possible actions based on the current states of both models and further adjusts the ratio of flows to be labeled in each phase. Extensive evaluation based on real traffic traces shows that the proposed approach can stably predict elephants using the packets received in the first 10% of their lifetime with an accuracy of over 80%, and using only about 10% more control channel bandwidth than the baseline over the evolved SDNs.

Priority-based band sharing for secondary users in cognitive radio networks

To improve wireless spectrum utilization, cognitive radio networks (CRNs) allow secondary users (SUs) opportunistic access to the frequency bands owned by primary users (PUs), when such PUs are inactive. A fully distributed CRN architecture is quite favorable, as it does not require any centralized scheduling, nor does it require coordination between SUs via a common control channel. This can reduce cost and avoid single point-of-failure issues. However, uncoordinated access to the spectrum by competing SUs, if not done judiciously, can cause excessive collisions and limit performance, which can be detrimental to the usefulness of CRNs, especially if some SUs have urgent traffic to send. Hence, we present a novel protocol to support traffic with multiple classes of priority within a fully distributed CRN. In such protocol, competing SUs attempt to access the spectrum autonomously, but rationally, based on their priority level, opting to transmit their packets when it is beneficial to both the SU itself and also to the overall system performance. Simulations confirm that the proposed protocol achieves excellent overall network performance, while ensuring that higher priority packets experience higher throughput and smaller delay compared to lower priority packets.

Electrochemical Impedance Spectroscopy-Based Microfluidic Biosensor Using Cell-Imprinted Polymers for Bacteria Detection.

The rapid and sensitive detection of bacterial contaminants using low-cost and portable point-of-need (PoN) biosensors has gained significant interest in water quality monitoring. Cell-imprinted polymers (CIPs) are emerging as effective and inexpensive materials for bacterial detection as they provide specific binding sites designed to capture whole bacterial cells, especially when integrated into PoN microfluidic devices. However, improving the sensitivity and detection limits of these sensors remains challenging. In this study, we integrated CIP-functionalized stainless steel microwires (CIP-MWs) into a microfluidic device for the impedimetric detection of E. coli bacteria. The sensor featured two parallel microchannels with three-electrode configurations that allowed simultaneous control and electrochemical impedance spectroscopy (EIS) measurements. A CIP-MW and a non-imprinted polymer (NIP)-MW suspended perpendicular to the microchannels served as the working electrodes in the test and control channels, respectively. Electrochemical spectra were fitted with equivalent electrical circuits, and the charge transfer resistances of both cells were measured before and after incubation with target bacteria. The charge transfer resistance of the CIP-MWs after 30 min of incubation with bacteria was increased. By normalizing the change in charge transfer resistance and analyzing the dose-response curve for bacterial concentrations ranging from 0 to 107 CFU/mL, we determined the limits of detection and quantification as 2 × 102 CFU/mL and 1.4 × 104 CFU/mL, respectively. The sensor demonstrated a dynamic range of 102 to 107 CFU/mL, where bacterial counts were statistically distinguishable. The proposed sensor offers a sensitive, cost-effective, durable, and rapid solution for on-site identification of waterborne pathogens.

Rainfall in California: Special Reference to 2023 Rains That Caused Floods

After years of crippling drought, California experienced a barrage of intense atmospheric river storms starting from late 2022 and continuing into early 2023 after so many years of extensive drought. This resulted in extensive flooding across the northern and central parts of the state. Major urban centers like San Francisco and Sacramento saw their wettest January on record, with damage to infrastructure and thousands evacuated in flooded areas. Southern California also saw higher than average rainfall. The extensive rainfall provided much-needed relief from the recent drought, helping to replenish reservoirs and groundwater basins, but also causing lot of catastrophic events due to California’s insufficient flood control infrastructure. Decades of underfunding and lack of coordination have left dams, levees, and urban flood control channels unable to handle increased precipitation, putting communities at risk. Historically, California has experienced periodic droughts, where precipitation falls well below average for multiple seasons or years. Significant droughts were observed in the past century such as in the years 1976–1977, 1987–1992, and 2012–2016. The most recent drought from 2012–2022 ranked as one of the most severe and most prolonged droughts on record in California. Although the 2023 storms helped in recovery from drought conditions, California must bolster its flood control systems and water storage capabilities. The state must prepare for a future where climate change drives intense precipitation alongside more intense droughts. Sustainable infrastructure and coordinated management will be vital for withstanding increased hydrological extremes. This article examines the rainfall extremes of 2023 within the context of California’s drought history and makes recommendations for long-term water security to overcome increased climate variability.

Asynchronous event‐triggered control for switched T–S fuzzy systems under dual‐channel hybrid cyber attacks

AbstractThis article presents an asynchronous event‐triggered scheme for switched Takagi–Sugeno (T–S) fuzzy systems against dual‐channel hybrid cyber attacks. Different from existing results, both sensor and controller channels are subjected to aperiodic denial‐of‐service attacks and random false data injection attacks. To efficiently utilize dual‐channel network communication resources while resisting hybrid attacks, two resilient event‐triggered mechanisms (ETMs) are constructed. Considering asynchronous ETMs and hybrid cyber attacks, the time‐delay switched T–S fuzzy system is derived by utilizing model transformation methods. Thereby, the stability conditions are derived by utilizing multiple Lyapunov functions technique, and slack matrices are introduced to further relax the conditions. Finally, two examples are given to demonstrate the effectiveness of the developed event‐based security control strategy.

Search for Time-Dependent CP Violation in D0→π+π−π0 Decays

A measurement of time-dependent CP violation in D0→π+π−π0 decays using a pp collision data sample collected by the LHCb experiment in 2012 and from 2015 to 2018, corresponding to an integrated luminosity of 7.7 fb−1, is presented. The initial flavor of each D0 candidate is determined from the charge of the pion produced in the D*(2010)+→D0π+ decay. The decay D0→K−π+π0 is used as a control channel to validate the measurement procedure. The gradient of the time-dependent CP asymmetry ΔY in D0→π+π−π0 decays is measured to be ΔY=(−1.3±6.3±2.4)×10−4, where the first uncertainty is statistical and the second is systematic, which is compatible with CP conservation. © 2024 CERN, for the LHCb Collaboration 2024 CERN

Fabrication of novel 316L stainless steel scaffolds by combining freeze-casting and 3D-printed gyroid templating techniques

Porous metals have been widely investigated as bioimplants to repair cancellous bone defects. Nevertheless, how to endure extreme stress and strike a balance between load-bearing performance, elastic modulus, and permeability are important issues. Freeze-casting is a novel technique for manufacturing micro-scale open-cellular lamellar porous materials. However, the pore size is relatively small because of the inherent constraints of the ice template. On the other hand, the scaffold with gyroid pore structures has been proven to have higher permeability due to its larger and smoother channels. To combine the advantages of both porous structures, the present study aims to develop dual-scale 316L stainless steel (316L SS) porous structures by incorporating the 3D-printed gyroid templates into the freeze-casting to further improve the lightweight, specific strength, energy absorption, and permeability of the porous structures. The results showed that macro-scale gyroid channels were successfully built into the micro-scale open-cellular lamellar porous scaffolds. The porosity of dual-scale scaffolds was 70.1 %–74.4 %, which was higher than that of 53.1 %–66.5 % in the single-scale scaffolds. The elastic moduli of the single-scale scaffolds were higher than that of the dual-scale scaffolds; both were within the range of human cancellous bone, demonstrating their mechanical compatibility. Furthermore, the dual-scale scaffolds presented a prominent rise in permeability compared to the single-scale scaffolds. Notably, the permeability of the 3G series scaffolds was comparable to human cancellous bone. In summary, the hierarchical 316L SS scaffolds with controllable macro-scale gyroid channels exhibit great potential for biomedical applications.

УТОЧНЕНА МОДЕЛЬ ДВОКАНАЛЬНОГО ЕЛЕКТРОПРИВОДА ПОДАЧІ З ПІДСУМОВУВАННЯМ РУХІВ НА ХОДОВІЙ ГАЙЦІ ДЛЯ ВИСОКОТОЧНИХ МЕТАЛОРІЗАЛЬНИХ ВЕРСТАТІВ

The iterative two-channel feed electric drive (ED) with the summation of movements on the rotating sliding nut (RSN) is designed to increase the speed and accuracy of traditional single-channel ED feed mechanisms (FM) of metal-cutting machines with an inertial working tool (WT). A refined generalized mathematical model of movement of the two-channel ED with RSN was obtained, which was built for WT FM of the high-precision coordinate metal-cutting ma-chine of the 24К60АФ4 model. The model takes into account the main static moments of resistance during metalwork-ing, as well as the nonlinear nature of the sliding friction forces in the machine WT FM. Convenient recurrence rela-tions are obtained for the calculation and modeling of sections of the linearized friction characteristic. The structural-algorithmic diagram of the compensated iterative two-channel feed ED with subordinate configuration of control chan-nels is proposed, which makes it possible to compensate in steady-state conditions the negative impact on the accuracy of WT feed of the main static moments of resistance and nonlinearities of sliding friction forces in the drive load. Ref. 9, fig. 3, table.

Self-distillation enhanced adaptive pruning of convolutional neural networks

Convolutional neural networks (CNNs) suffer from issues of large parameter size and high computational complexity. To address this, we propose an adaptive pruning algorithm based on self-distillation. The algorithm introduces a trainable parameter for each channel to control channel pruning and integrates the pruning process into network training, enabling pruning and fine-tuning in a single training iteration to derive the final pruned model. Moreover, this framework requires only a single overall pruning rate to achieve adaptive pruning for each layer, avoiding tedious hyperparameter tuning for a less iterative, simple and efficient pruning process. Additionally, self-distillation is utilized in the pruning algorithm, leveraging the knowledge from the pretrained CNN to guide its own pruning process, facilitating the recovery from performance degradation caused by pruning and achieving higher accuracy. Extensive pruning experiments on various CNN models over different datasets demonstrate that at least 75% of redundant parameters can be reduced without sacrificing model accuracy.

Vascular Function and Ion Channels in Alzheimer's Disease.

This review paper explores the critical role of vascular ion channels in the regulation of cerebral artery function and examines the impact of Alzheimer's disease (AD) on these processes. Vascular ion channels are fundamental in controlling vascular tone, blood flow, and endothelial function in cerebral arteries. Dysfunction of these channels can lead to impaired cerebral autoregulation, contributing to cerebrovascular pathologies. AD, characterized by the accumulation of amyloid beta (Aβ) plaques and neurofibrillary tangles, has been increasingly linked to vascular abnormalities, including altered vascular ion channel activity. Here, we briefly review the role of vascular ion channels in cerebral blood flow control and neurovascular coupling. We then examine the vascular defects in AD, the current understanding of how AD pathology affects vascular ion channel function, and how these changes may lead to compromised cerebral blood flow and neurodegenerative processes. Finally, we provide future perspectives and conclusions. Understanding this topic is important as ion channels may be potential therapeutic targets for improving cerebrovascular health and mitigating AD progression.

Performance Analysis of NR Polar Codes at Short Information Blocks for Control Channels

Performance Analysis of NR Polar Codes at Short Information Blocks for Control Channels

Comprehensively enhancing the security of control with combined homomorphic encryption

Homomorphic encryption is an effective way to address the privacy and security issues of Networked Control Systems (NCSs). Since the control function needs to be redesigned according to the homomorphism to complete encrypted computing, the practical implementation of a perfectly secure and highly efficient NCS is challenging. Previously proposed NCSs based on homomorphic encryption are still subject to the risk of eavesdropping attacks. In this paper, a combined homomorphic encryption scheme is designed to build a secure environment for NCSs. This scheme comprehensively enhances the security of NCSs by eliminating potential security hazards. The risk of eavesdropping attacks on information in the controller and communication channel is avoided. More specifically, the entire control scheme is encrypted and privacy computing within the controller is performed on this basis. Data protection is provided for all transmission channels, including the transmission of the intermediate result and controller state. In particular, the computational efficiency of the encrypted control system is fast and feasible for real-time control. The performance and stability of the closed-loop system are maintained.

DIS-Guard: Enhancing SDN resilience to topology and RCO attacks

SDN controllers employ discovery protocols with LLDP packets to discover the network topology; however, this approach is susceptible to topology attacks due to the static reuse of LLDP packets without proper origin verification or integrity checks. This paper proposes a novel form of topology attack called the Round-trip time Confusion Onslaught (RCO) attack. Our findings showcase the capability of the RCO attack to mislead the discovery service of SDN controllers and bypass the Real-time Link Verification (RLV) defence mechanism, which depends on timing features in Machine Learning (ML) models. The RCO attack significantly reduces the effectiveness of the RLV mechanism in terms of True Positive Rate (TPR), Precision, F1-score, and Cohen’s Kappa and increases the False Positive Rate (FPR). These results underscore the difficulties in achieving dependable ML accuracy in topology attack detection. Accordingly, we propose the DIS-Guard framework, designed to protect and improve the efficiency of discovery protocols within SDN controllers. This framework utilizes the mutual Transport Layer Security (mTLS) protocol to discover hosts proactively. Moreover, it employs a novel combination of a chaos-tent map and the proposed statistical method for link discovery. Through extensive evaluation, we illustrate DIS-Guard’s superior performance and security over the established Ryu (switches.py) controller and the RLV defence mechanism. Notably, DIS-Guard reduces host-to-host access delays, decreases LLDP packet transmission and reception significantly, and improves control channel efficiency. Collectively, these quantifiable benefits manifest the efficacy of DIS-Guard as a significantly optimized solution for SDN security and performance.