Visible to the public Biblio

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2023-09-08
Chen, Xuan, Li, Fei.  2022.  Research on the Algorithm of Situational Element Extraction of Internet of Vehicles Security based on Optimized-FOA-PNN. 2022 7th International Conference on Cyber Security and Information Engineering (ICCSIE). :109–112.

The scale of the intelligent networked vehicle market is expanding rapidly, and network security issues also follow. A Situational Awareness (SA) system can detect, identify, and respond to security risks from a global perspective. In view of the discrete and weak correlation characteristics of perceptual data, this paper uses the Fly Optimization Algorithm (FOA) based on dynamic adjustment of the optimization step size to improve the convergence speed, and optimizes the extraction model of security situation element of the Internet of Vehicles (IoV), based on Probabilistic Neural Network (PNN), to improve the accuracy of element extraction. Through the comparison of experimental algorithms, it is verified that the algorithm has fast convergence speed, high precision and good stability.

2023-01-20
Khan, Rashid, Saxena, Neetesh, Rana, Omer, Gope, Prosanta.  2022.  ATVSA: Vehicle Driver Profiling for Situational Awareness. 2022 IEEE European Symposium on Security and Privacy Workshops (EuroS&PW). :348–357.

Increasing connectivity and automation in vehicles leads to a greater potential attack surface. Such vulnerabilities within vehicles can also be used for auto-theft, increasing the potential for attackers to disable anti-theft mechanisms implemented by vehicle manufacturers. We utilize patterns derived from Controller Area Network (CAN) bus traffic to verify driver “behavior”, as a basis to prevent vehicle theft. Our proposed model uses semi-supervised learning that continuously profiles a driver, using features extracted from CAN bus traffic. We have selected 15 key features and obtained an accuracy of 99% using a dataset comprising a total of 51 features across 10 different drivers. We use a number of data analysis algorithms, such as J48, Random Forest, JRip and clustering, using 94K records. Our results show that J48 is the best performing algorithm in terms of training and testing (1.95 seconds and 0.44 seconds recorded, respectively). We also analyze the effect of using a sliding window on algorithm performance, altering the size of the window to identify the impact on prediction accuracy.

Leak, Matthew Haslett, Venayagamoorthy, Ganesh Kumar.  2022.  Situational Awareness of De-energized Lines During Loss of SCADA Communication in Electric Power Distribution Systems. 2022 IEEE/PES Transmission and Distribution Conference and Exposition (T&D). :1–5.

With the electric power distribution grid facing ever increasing complexity and new threats from cyber-attacks, situational awareness for system operators is quickly becoming indispensable. Identifying de-energized lines on the distribution system during a SCADA communication failure is a prime example where operators need to act quickly to deal with an emergent loss of service. Loss of cellular towers, poor signal strength, and even cyber-attacks can impact SCADA visibility of line devices on the distribution system. Neural Networks (NNs) provide a unique approach to learn the characteristics of normal system behavior, identify when abnormal conditions occur, and flag these conditions for system operators. This study applies a 24-hour load forecast for distribution line devices given the weather forecast and day of the week, then determines the current state of distribution devices based on changes in SCADA analogs from communicating line devices. A neural network-based algorithm is applied to historical events on Alabama Power's distribution system to identify de-energized sections of line when a significant amount of SCADA information is hidden.

Milov, Oleksandr, Khvostenko, Vladyslav, Natalia, Voropay, Korol, Olha, Zviertseva, Nataliia.  2022.  Situational Control of Cyber Security in Socio-Cyber-Physical Systems. 2022 International Congress on Human-Computer Interaction, Optimization and Robotic Applications (HORA). :1–6.

The features of socio-cyber-physical systems are presented, which dictate the need to revise traditional management methods and transform the management system in such a way that it takes into account the presence of a person both in the control object and in the control loop. The use of situational control mechanisms is proposed. The features of this approach and its comparison with existing methods of situational awareness are presented. The comparison has demonstrated wider possibilities and scope for managing socio-cyber-physical systems. It is recommended to consider a wider class of types of relations that exist in socio-cyber-physical systems. It is indicated that such consideration can be based on the use of pseudo-physical logics considered in situational control. It is pointed out that it is necessary to design a classifier of situations (primarily in cyberspace), instead of traditional classifiers of threats and intruders.

Djeachandrane, Abhishek, Hoceini, Said, Delmas, Serge, Duquerrois, Jean-Michel, Mellouk, Abdelhamid.  2022.  QoE-based Situational Awareness-Centric Decision Support for Network Video Surveillance. ICC 2022 - IEEE International Conference on Communications. :335–340.

Control room video surveillance is an important source of information for ensuring public safety. To facilitate the process, a Decision-Support System (DSS) designed for the security task force is vital and necessary to take decisions rapidly using a sea of information. In case of mission critical operation, Situational Awareness (SA) which consists of knowing what is going on around you at any given time plays a crucial role across a variety of industries and should be placed at the center of our DSS. In our approach, SA system will take advantage of the human factor thanks to the reinforcement signal whereas previous work on this field focus on improving knowledge level of DSS at first and then, uses the human factor only for decision-making. In this paper, we propose a situational awareness-centric decision-support system framework for mission-critical operations driven by Quality of Experience (QoE). Our idea is inspired by the reinforcement learning feedback process which updates the environment understanding of our DSS. The feedback is injected by a QoE built on user perception. Our approach will allow our DSS to evolve according to the context with an up-to-date SA.

Kim, Yeongwoo, Dán, György.  2022.  An Active Learning Approach to Dynamic Alert Prioritization for Real-time Situational Awareness. 2022 IEEE Conference on Communications and Network Security (CNS). :154–162.

Real-time situational awareness (SA) plays an essential role in accurate and timely incident response. Maintaining SA is, however, extremely costly due to excessive false alerts generated by intrusion detection systems, which require prioritization and manual investigation by security analysts. In this paper, we propose a novel approach to prioritizing alerts so as to maximize SA, by formulating the problem as that of active learning in a hidden Markov model (HMM). We propose to use the entropy of the belief of the security state as a proxy for the mean squared error (MSE) of the belief, and we develop two computationally tractable policies for choosing alerts to investigate that minimize the entropy, taking into account the potential uncertainty of the investigations' results. We use simulations to compare our policies to a variety of baseline policies. We find that our policies reduce the MSE of the belief of the security state by up to 50% compared to static baseline policies, and they are robust to high false alert rates and to the investigation errors.

Yong, Li, Mu, Chen, ZaoJian, Dai, Lu, Chen.  2022.  Security situation awareness method of power mobile application based on big data architecture. 2022 5th International Conference on Data Science and Information Technology (DSIT). :1–6.

According to the characteristics of security threats and massive users in power mobile applications, a mobile application security situational awareness method based on big data architecture is proposed. The method uses open-source big data technology frameworks such as Kafka, Flink, Elasticsearch, etc. to complete the collection, analysis, storage and visual display of massive power mobile application data, and improve the throughput of data processing. The security situation awareness method of power mobile application takes the mobile terminal threat index as the core, divides the risk level for the mobile terminal, and predicts the terminal threat index through support vector machine regression algorithm (SVR), so as to construct the security profile of the mobile application operation terminal. Finally, through visualization services, various data such as power mobile applications and terminal assets, security operation statistics, security strategies, and alarm analysis are displayed to guide security operation and maintenance personnel to carry out power mobile application security monitoring and early warning, banning disposal and traceability analysis and other decision-making work. The experimental analysis results show that the method can meet the requirements of security situation awareness for threat assessment accuracy and response speed, and the related results have been well applied in a power company.

2022-02-07
Yifan, Zhao.  2021.  Application of Machine Learning in Network Security Situational Awareness. 2021 World Conference on Computing and Communication Technologies (WCCCT). :39–46.
Along with the advance of science and technology, informationization society construction is gradually perfect. The development of modern information technology has driven the growth of the entire network spatial data, and network security is a matter of national security. There are several countries included in the national security strategy, with the increase of network space connected point, traditional network security space processing way already cannot adapt to the demand. Machine learning can effectively solve the problem of network security. Around the machine learning technology applied in the field of network security research results, this paper introduces the basic concept of network security situational awareness system, the basic model, and system framework. Based on machine learning, this paper elaborates the network security situation awareness technology, including data mining technology, feature extraction technology and situation prediction technology. Recursive feature elimination, decision tree algorithm, support vector machine, and future research direction in the field of network security situational awareness are also discussed.
2021-11-29
Silva-Saravia, Horacio, Singh, Iknoor, Chynoweth, Joshua, Mateo, Norbo, Mejia, Manuel, Amadis, Simon, Alvarez, Rufino.  2020.  Islanding Detection and Resynchronization Based upon Wide-Area Monitoring and Situational Awareness in the Dominican Republic. 2020 IEEE PES Transmission Distribution Conference and Exhibition - Latin America (T D LA). :1–6.
This paper shows the benefits of synchrophasor technology for islanding detection and resynchronization in the control room at Empresa de Transmisión Eléctrica Dominicana (ETED) in the Dominican Republic. EPG's Real Time Dynamics Monitoring System (RTDMS®) deployed at ETED was tested during operator training with the event data after an islanding event occurred on October 26, 2019, which caused the ETED System to split into two islands. RTDMS's islanding detection algorithm quickly detected and identified the event. The islanding situation was not clear for operators during the time of the event with the use of traditional SCADA tools. The use of synchophasor technology also provides valuable information for a quick and safe resynchronization. By monitoring the system frequency in each island and voltage angle differences between islands, operators can know the exact time of circuit breaker closure for a successful resynchronization. Synchrophasors allow the resynchronization in a relatively short time, avoiding the risk of additional load loss, generator outages or even a wider system blackout.
Wang, Yixuan, Li, Yujun, Chen, Xiang, Luo, Yeni.  2020.  Implementing Network Attack Detection with a Novel NSSA Model Based on Knowledge Graphs. 2020 IEEE 19th International Conference on Trust, Security and Privacy in Computing and Communications (TrustCom). :1727–1732.
With the rapid development of networks, cyberspace security is facing increasingly severe challenges. Traditional alert aggregation process and alert correlation analysis process are susceptible to a large amount of redundancy and false alerts. To tackle the challenge, this paper proposes a network security situational awareness model KG-NSSA (Knowledge-Graph-based NSSA) based on knowledge graphs. This model provides an asset-based network security knowledge graph construction scheme. Based on the network security knowledge graph, a solution is provided for the classic problem in the field of network security situational awareness - network attack scenario discovery. The asset-based network security knowledge graph combines the asset information of the monitored network and fully considers the monitoring of network traffic. The attack scenario discovery according to the KG-NSSA model is to complete attack discovery and attack association through attribute graph mining and similarity calculation, which can effectively reflect specific network attack behaviors and mining attack scenarios. The effectiveness of the proposed method is verified on the MIT DARPA2000 data set. Our work provides a new approach for network security situational awareness.
Li, Jingyi, Yi, Xiaoyin, Wei, Shi.  2020.  A Study of Network Security Situational Awareness in Internet of Things. 2020 International Wireless Communications and Mobile Computing (IWCMC). :1624–1629.
As the application of Internet of Things technology becomes more common, the security problems derived from it became more and more serious. Different from the traditional Internet, the security of the Internet of Things presented new features. This paper introduced the current situation of Internet of Things security, generalized the definitions of situation awareness and network security situation awareness, and finally discussed the methods of establishing security situational awareness of Internet of Things which provided some tentative solutions to the new DDoS attack caused by Internet of Things terminals.
Alavi, S. A., Rahimian, A., Mehran, K..  2020.  Statistical Estimation Framework for State Awareness in Microgrids Based on IoT Data Streams. The 10th International Conference on Power Electronics, Machines and Drives (PEMD 2020). 2020:855–860.
This paper presents an event-triggered statistical estimation strategy and a data collection architecture for situational awareness (SA) in microgrids. An estimation agent structure based on the event-triggered Kalman filter is proposed and implemented for state estimation layer of the SA using long range wide area network (LoRAWAN) protocol. A setup has been developed which provides enormous data collection capabilities from smart meters in order to realize an adequate level of SA in microgrids. Thingsboard Internet of things (IoT) platform is used for the SA visualization with a customized dashboard. It is shown that by using the developed estimation strategy, an adequate level of SA can be achieved with a minimum installation and communication cost to have an accurate average state estimation of the microgrid.
Imanimehr, Fatemeh, Gharaee, Hossein, Enayati, Alireza.  2020.  An Architecture for National Information Sharing and Alerting System. 2020 10th International Symposium onTelecommunications (IST). :217–221.
Protecting critical infrastructure from cyber threats is one of the most important obligations of governments to ensure the national and social security of the society. Developing national cyber situational awareness platform provides a protection of critical infrastructures. In such a way, each infrastructure, independently, generates its own situational awareness and shares it with other infrastructures through a national sharing and alerting center. The national information sharing and alerting center collects cyber information of infrastructures and draws a picture of national situational awareness by examining the potential effects of received threats on other infrastructures and predicting the national cyber status in near future. This paper represents the conceptual architecture for such national sharing system and suggests some brief description of its implementation.
Carroll, Fiona, Legg, Phil, Bønkel, Bastian.  2020.  The Visual Design of Network Data to Enhance Cyber Security Awareness of the Everyday Internet User. 2020 International Conference on Cyber Situational Awareness, Data Analytics and Assessment (CyberSA). :1–7.
Technology and the use of online services are very prevalent across much of our everyday lives. As our digital interactions continue to grow, there is a need to improve public awareness of the risks to our personal online privacy and security. Designing for cyber security awareness has never been so important. In this work, we consider people's current impressions towards their privacy and security online. We also explore how abnormal network activity data can be visually conveyed to afford a heightened cyber security awareness. In detail, the paper documents the different effects of visual variables in an edge and node DoS visualisation to depict abnormally high volumes of traffic. The results from two studies show that people are generally becoming more concerned about their privacy and security online. Moreover, we have found that the more focus based visual techniques (i.e. blur) and geometry-based techniques (i.e. jaggedness and sketchiness) afford stronger impressions of uncertainty from abnormally high volumes of network traffic. In terms of security, these impressions and feelings alert in the end-user that something is not quite as it should be and hence develop a heightened cyber security awareness.
Shahsavari, Alireza, Farajollahi, Mohammad, Stewart, Emma, Rad, Hamed Mohsenian.  2020.  Situational Awareness in Distribution Grid Using Micro-PMU Data: A Machine Learning Approach. 2020 IEEE Power Energy Society General Meeting (PESGM). :1–1.
The recent development of distribution-level phasor measurement units, a.k.a. micro-PMUs, has been an important step towards achieving situational awareness in power distribution networks. The challenge however is to transform the large amount of data that is generated by micro-PMUs to actionable information and then match the information to use cases with practical value to system operators. This open problem is addressed in this paper. First, we introduce a novel data-driven event detection technique to pick out valuable portion of data from extremely large raw micro-PMU data. Subsequently, a datadriven event classifier is developed to effectively classify power quality events. Importantly, we use field expert knowledge and utility records to conduct an extensive data-driven event labeling. Moreover, certain aspects from event detection analysis are adopted as additional features to be fed into the classifier model. In this regard, a multi-class support vector machine (multi-SVM) classifier is trained and tested over 15 days of real-world data from two micro-PMUs on a distribution feeder in Riverside, CA. In total, we analyze 1.2 billion measurement points, and 10,700 events. The effectiveness of the developed event classifier is compared with prevalent multi-class classification methods, including k-nearest neighbor method as well as decision-tree method. Importantly, two real-world use-cases are presented for the proposed data analytics tools, including remote asset monitoring and distribution-level oscillation analysis.
Arunagirinathan, Paranietharan, Venayagamoorthy, Ganesh K..  2020.  Situational Awareness of Power System Stabilizers’ Performance in Energy Control Centers. 2020 IEEE International Conference on Fuzzy Systems (FUZZ-IEEE). :1–8.
Undamped power system oscillations are detrimental to stable and security of the electric grid. Historically, poorly damped low frequency rotor oscillations have caused system blackouts or brownouts. It is required to monitor the oscillation damping controllers such as power system stabilizers' (PSS) performance at energy control centers as well as at power plant control centers. Phasor measurement units (PMUs) based time response and frequency response information on PSS performance is collected. A fuzzy logic system is developed to combine the time and frequency response information to derive the situational awareness on PSS performance on synchronous generator's oscillation(s). A two-area four-machine benchmark power system is simulated on a real-time digital simulator platform. Fuzzy logic system developed is evaluated for different system disturbances. Situational awareness on PSS performance on synchronous generator's oscillation(s) allows the control center operator to enhance the power system operation more stable and secure.
Ma, Chuang, You, Haisheng, Wang, Li, Zhang, Jiajun.  2020.  Intelligent Cybersecurity Situational Awareness Model Based on Deep Neural Network. 2020 International Conference on Cyber-Enabled Distributed Computing and Knowledge Discovery (CyberC). :76–83.
In recent years, we have faced a series of online threats. The continuous malicious attacks on the network have directly caused a huge threat to the user's spirit and property. In order to deal with the complex security situation in today's network environment, an intelligent network situational awareness model based on deep neural networks is proposed. Use the nonlinear characteristics of the deep neural network to solve the nonlinear fitting problem, establish a network security situation assessment system, take the situation indicators output by the situation assessment system as a guide, and collect on the main data features according to the characteristics of the network attack method, the main data features are collected and the data is preprocessed. This model designs and trains a 4-layer neural network model, and then use the trained deep neural network model to understand and analyze the network situation data, so as to build the network situation perception model based on deep neural network. The deep neural network situational awareness model designed in this paper is used as a network situational awareness simulation attack prediction experiment. At the same time, it is compared with the perception model using gray theory and Support Vector Machine(SVM). The experiments show that this model can make perception according to the changes of state characteristics of network situation data, establish understanding through learning, and finally achieve accurate prediction of network attacks. Through comparison experiments, datatypized neural network deep neural network situation perception model is proved to be effective, accurate and superior.
Chandra, Nungky Awang, Putri Ratna, Anak Agung, Ramli, Kalamullah.  2020.  Development of a Cyber-Situational Awareness Model of Risk Maturity Using Fuzzy FMEA. 2020 International Workshop on Big Data and Information Security (IWBIS). :127–136.
This paper uses Endsley's situational awareness model as a starting point for creating a new cyber-security awareness model for risk maturity. This is used to model the relationship between risk management-based situational awareness and levels of maturity in making decisions to deal with potential cyber-attacks. The risk maturity related to cyber situational awareness using the fuzzy failure mode effect analysis (FMEA) method is needed as a basis for effective risk-based decision making and to measure the level of maturity in decision making using the Software Engineering Institute Capability Maturity Model Integration (SEI CMMI) approach. The novelty of this research is that it builds a model of the relationship between the level of maturity and the level of risk in cyber-situational awareness. Based on the data during the COVID-19 pandemic, there was a decrease in the number of incidents, including the following decreases: from 15-29 cases of malware attacks to 8-12 incidents, from 20-35 phishing cases to 12-15 cases and from 5-10 ransomware cases to 5-6 cases.
2021-09-30
Peng, Cheng, Yongli, Wang, Boyi, Yao, Yuanyuan, Huang, Jiazhong, Lu, Qiao, Peng.  2020.  Cyber Security Situational Awareness Jointly Utilizing Ball K-Means and RBF Neural Networks. 2020 17th International Computer Conference on Wavelet Active Media Technology and Information Processing (ICCWAMTIP). :261–265.
Low accuracy and slow speed of predictions for cyber security situational awareness. This paper proposes a network security situational awareness model based on accelerated accurate k-means radial basis function (RBF) neural network, the model uses the ball k-means clustering algorithm to cluster the input samples, to get the nodes of the hidden layer of the RBF neural network, speeding up the selection of the initial center point of the RBF neural network, and optimize the parameters of the RBF neural network structure. Finally, use the training data set to train the neural network, using the test data set to test the accuracy of this neural network structure, the results show that this method has a greater improvement in training speed and accuracy than other neural networks.
2021-04-09
Lyshevski, S. E., Aved, A., Morrone, P..  2020.  Information-Centric Cyberattack Analysis and Spatiotemporal Networks Applied to Cyber-Physical Systems. 2020 IEEE Microwave Theory and Techniques in Wireless Communications (MTTW). 1:172—177.

Cyber-physical systems (CPS) depend on cybersecurity to ensure functionality, data quality, cyberattack resilience, etc. There are known and unknown cyber threats and attacks that pose significant risks. Information assurance and information security are critical. Many systems are vulnerable to intelligence exploitation and cyberattacks. By investigating cybersecurity risks and formal representation of CPS using spatiotemporal dynamic graphs and networks, this paper investigates topics and solutions aimed to examine and empower: (1) Cybersecurity capabilities; (2) Information assurance and system vulnerabilities; (3) Detection of cyber threat and attacks; (4) Situational awareness; etc. We introduce statistically-characterized dynamic graphs, novel entropy-centric algorithms and calculi which promise to ensure near-real-time capabilities.

2021-02-08
Nikouei, S. Y., Chen, Y., Faughnan, T. R..  2018.  Smart Surveillance as an Edge Service for Real-Time Human Detection and Tracking. 2018 IEEE/ACM Symposium on Edge Computing (SEC). :336—337.

Monitoring for security and well-being in highly populated areas is a critical issue for city administrators, policy makers and urban planners. As an essential part of many dynamic and critical data-driven tasks, situational awareness (SAW) provides decision-makers a deeper insight of the meaning of urban surveillance. Thus, surveillance measures are increasingly needed. However, traditional surveillance platforms are not scalable when more cameras are added to the network. In this work, a smart surveillance as an edge service has been proposed. To accomplish the object detection, identification, and tracking tasks at the edge-fog layers, two novel lightweight algorithms are proposed for detection and tracking respectively. A prototype has been built to validate the feasibility of the idea, and the test results are very encouraging.

2020-12-15
Reardon, C., Lee, K., Fink, J..  2018.  Come See This! Augmented Reality to Enable Human-Robot Cooperative Search. 2018 IEEE International Symposium on Safety, Security, and Rescue Robotics (SSRR). :1—7.

Robots operating alongside humans in field environments have the potential to greatly increase the situational awareness of their human teammates. A significant challenge, however, is the efficient conveyance of what the robot perceives to the human in order to achieve improved situational awareness. We believe augmented reality (AR), which allows a human to simultaneously perceive the real world and digital information situated virtually in the real world, has the potential to address this issue. Motivated by the emerging prevalence of practical human-wearable AR devices, we present a system that enables a robot to perform cooperative search with a human teammate, where the robot can both share search results and assist the human teammate in navigation to the search target. We demonstrate this ability in a search task in an uninstrumented environment where the robot identifies and localizes targets and provides navigation direction via AR to bring the human to the correct target.

2020-12-07
Allig, C., Leinmüller, T., Mittal, P., Wanielik, G..  2019.  Trustworthiness Estimation of Entities within Collective Perception. 2019 IEEE Vehicular Networking Conference (VNC). :1–8.
The idea behind collective perception is to improve vehicles' awareness about their surroundings. Every vehicle shares information describing its perceived environment by means of V2X communication. Similar to other information shared using V2X communication, collective perception information is potentially safety relevant, which means there is a need to assess the reliability and quality of received information before further processing. Transmitted information may have been forged by attackers or contain inconsistencies e.g. caused by malfunctions. This paper introduces a novel approach for estimating a belief that a pair of entities, e.g. two remote vehicles or the host vehicle and a remote vehicle, within a Vehicular ad hoc Network (VANET) are both trustworthy. The method updates the belief based on the consistency of the data that both entities provide. The evaluation shows that the proposed method is able to identify forged information.
2020-08-17
Małowidzki, Marek, Hermanowski, Damian, Bereziński, Przemysław.  2019.  TAG: Topological Attack Graph Analysis Tool. 2019 3rd Cyber Security in Networking Conference (CSNet). :158–160.
Attack graphs are a relatively new - at least, from the point of view of a practical usage - method for modeling multistage cyber-attacks. They allow to understand how seemingly unrelated vulnerabilities may be combined together by an attacker to form a chain of hostile actions that enable to compromise a key resource. An attack graph is also the starting point for providing recommendations for corrective actions that would fix or mask security problems and prevent the attacks. In the paper, we propose TAG, a topological attack graph analysis tool designed to support a user in a security evaluation and countermeasure selection. TAG employs an improved version of MulVAL inference engine, estimates a security level on the basis of attack graph and attack paths scoring, and recommends remedial actions that improve the security of the analyzed system.
2020-03-16
Ren, Wenyu, Yu, Tuo, Yardley, Timothy, Nahrstedt, Klara.  2019.  CAPTAR: Causal-Polytree-based Anomaly Reasoning for SCADA Networks. 2019 IEEE International Conference on Communications, Control, and Computing Technologies for Smart Grids (SmartGridComm). :1–7.
The Supervisory Control and Data Acquisition (SCADA) system is the most commonly used industrial control system but is subject to a wide range of serious threats. Intrusion detection systems are deployed to promote the security of SCADA systems, but they continuously generate tremendous number of alerts without further comprehending them. There is a need for an efficient system to correlate alerts and discover attack strategies to provide explainable situational awareness to SCADA operators. In this paper, we present a causal-polytree-based anomaly reasoning framework for SCADA networks, named CAPTAR. CAPTAR takes the meta-alerts from our previous anomaly detection framework EDMAND, correlates the them using a naive Bayes classifier, and matches them to predefined causal polytrees. Utilizing Bayesian inference on the causal polytrees, CAPTAR can produces a high-level view of the security state of the protected SCADA network. Experiments on a prototype of CAPTAR proves its anomaly reasoning ability and its capabilities of satisfying the real-time reasoning requirement.