Biblio

Implementation of self-healing control system in smart grid is a persisting challenge. Self-Healing control strategy is the important guarantee to implement the smart grid. In addition, it is the support of achieving the secure operation, improving the reliability and security of distribution grid, and realizing the smart distribution grid. Although self-healing control system concept is presented in smart grid context, but the complexity of distribution network structure recommended to choose advanced control and protection system using a self-healing, this system must be able to heal any disturbance in the distribution system of smart grid to improve efficiency, resiliency, continuity, and reliability of the smart grid. This review focuses mostly on the key technology of self-healing control, gives an insight into the role of self-healing in distribution system advantages, study challenges and opportunities in the prospect of utilities. The main contribution of this paper is demonstrating proposed architecture, control strategy for self-healing control system includes fault detection, fault localization, faulted area isolation, and power restoration in the electrical distribution system.

Technological developments in the energy sector while offering new business insights, also produces complex data. In this study, the relationship between smart grid and big data approaches have been investigated. After analyzing where the big data techniques and technologies are used in which areas of smart grid systems, the big data technologies used to detect attacks on smart grids have been focused on. Big data analytics produces efficient solutions, but it is more critical to choose which algorithm and metric. For this reason, an application prototype has been proposed using big data approaches to detect attacks on smart grids. The algorithms with high accuracy were determined as 92% with Random Forest and 87% with Decision Tree.

Combining conventional power networks and information communication technologies forms smart grid concept. Researches on the evolution of conventional power grid system into smart grid continue thanks to the development of communication and information technologies hopefully. Testing of smart grid systems is usually performed in simulation environments. However, achieving more effective real-world implementations, a smart grid application needs a real-world test environment, called testbed. Smart grid, which is the combination of conventional electricity line with information communication technologies, is vulnerable to cyber-attacks and this is a key challenge improving the smart grid. The vulnerabilities to cyber-attacks in smart grid arise from information communication technologies' nature inherently. Testbeds, which cyber-security researches and studies can be performed, are needed to find effective solutions against cyber-attacks capabilities in smart grid practices. In this paper, an evaluation of existing smart grid testbeds with the capability of cyber security is presented. First, background, domains, research areas and security issues in smart grid are introduced briefly. Then smart grid testbeds and features are explained. Also, existing security-oriented testbeds and cyber-attack testing capabilities of testbeds are evaluated. Finally, we conclude the study and give some recommendations for security-oriented testbed implementations.

This paper presents a review on how to benefit from software-defined networking (SDN) to enhance smart grid security. For this purpose, the attacks threatening traditional smart grid systems are classified according to availability, integrity, and confidentiality, which are the main cyber-security objectives. The traditional smart grid architecture is redefined with SDN and a conceptual model for SDN-based smart grid systems is proposed. SDN based solutions to the mentioned security threats are also classified and evaluated. Our conclusions suggest that SDN helps to improve smart grid security by providing real-time monitoring, programmability, wide-area security management, fast recovery from failures, distributed security and smart decision making based on big data analytics.

Smart grid utilizes cloud service to realize reliable, efficient, secured, and cost-effective power management, but there are a number of security risks in the cloud service of smart grid. The security risks are particularly problematic to operators of power information infrastructure who want to leverage the benefits of cloud. In this paper, security risk of cloud service in the smart grid are categorized and analyzed characteristics, and multi-layered index system of general technical risks is established, which applies to different patterns of cloud service. Cloud service risk of smart grid can evaluate according indexes.

The rapid evolution of the power grid into a smart one calls for innovative and compelling means to experiment with the upcoming expansions, and analyze their behavioral response under normal circumstances and when targeted by attacks. Such analysis is fundamental to setting up solid foundations for the smart grid. Smart grid Hardware-In-the-Loop (HIL) co-simulation environments serve as a key approach to answer questions on the systems components, functionality, security concerns along with analysis of the system outcome and expected behavior. In this paper, we introduce a HIL co-simulation framework capable of simulating the smart grid actions and responses to attacks targeting its power and communication components. Our testbed is equipped with a real-time power grid simulator, and an associated OpenStack-based communication network. Through the utilized communication network, we can emulate a multitude of attacks targeting the power system, and evaluating the grid response to those attacks. Moreover, we present different illustrative cyber attacks use cases, and analyze the smart grid behavior in the presence of those attacks.

The communication security issue brought by Smart Grid is of great importance and should not be ignored in backbone optical networks. With the aim to solve this problem, this paper firstly conducts deep analysis into the security challenge of optical network under smart power grid environment and proposes a so-called lightweight security signaling mechanism of multi-domain optical network for Energy Internet. The proposed scheme makes full advantage of current signaling protocol with some necessary extensions and security improvement. Thus, this lightweight security signaling protocol is designed to make sure the end-to-end trusted connection. Under the multi-domain communication services of smart power grid, evaluation simulation for the signaling interaction is conducted. Simulation results show that this proposed approach can greatly improve the security level of large-scale multi-domain optical network for smart power grid with better performance in term of connection success rate performance.

Modern critical infrastructures such as Smart Grids (SGs) rely heavily on Information and Communication Technology (ICT) systems to monitor and control operations and states within large-scale facilities. The potential offered by SGs includes an effective integration of renewables, a demand-response action and a dynamic pricing system. The increasing use of ICT for the communication infrastructure of modern power systems offers advantages but can give rise to cyber attacks that compromise the security of the SG. To deal efficiently with the security concerns of SGs, a survey of the different attacks that consider the physical as well as the cyber characteristics of modern power grids is required. In the present paper, first the specific differences between SGs with respect to both Information Technology (IT) systems and conventional energy grids are discussed. Thereafter, the specific security requirements of SGs are presented in order to raise awareness of the new security challenges. Finally, a new classification of cyber attacks, based on the architecture of the SG, is proposed and details for each category are provided. The new classification is distinguished by its focus on the cyber-physical security of the SG in particular, which gives a comprehensive overview of the different threats. Thus, this new classification forms the necessary knowledge-basis for the design of respective countermeasures.

Power systems domain has generally been very conservative in terms of conducting digital forensic investigations, especially so since the advent of smart grids. This lack of research due to a multitude of challenges has resulted in absence of knowledge base and resources to facilitate such an investigation. Digitalization in the form of smart grids is upon us but in case of cyber-attacks, attribution to such attacks is challenging and difficult if not impossible. In this research, we have identified digital forensic artifacts resulting from a cyber-attack on Wide Area Monitoring, Protection and Control (WAMPAC) systems, which will help an investigator attribute an attack using the identified evidences. The research also shows the usage of sandboxing for digital forensics along with hardware-in-the-loop (HIL) setup. This is first of its kind effort to identify and acquire all the digital forensic evidences for WAMPAC systems which will ultimately help in building a body of knowledge and taxonomy for power system forensics.

The existing radial topology makes the power system less reliable since any part in the system failure will disrupt electrical power delivery in the network. The increasing security concerns, electrical energy theft, and present advancement in Information and Communication Technologies are some factors that led to modernization of power system. In a smart grid, a network of smart sensors offers numerous opportunities that may include monitoring of power, consumer-side energy management, synchronization of dispersed power storage, and integrating sources of renewable energy. Smart sensor networks are low cost and are ease to deploy hence they are favorable contestants for deployment smart power grids at a larger scale. These networks will result in a colossal volume of dissimilar range of data that require an efficient processing and analyzing process in order to realize an efficient smart grid. The existing technology can be used to collect data but dealing with the collected information proficiently as well as mining valuable material out of it remains challenging. The paper investigates communication technologies that maybe deployed in a smart grid. In this paper simulations results for the Additive White Gaussian Noise (AWGN) channel are illustrated. We propose a model and a communication network domain riding on the power system domain. The model was interrogated by simulation in MATLAB.

This paper proposes a game-theoretic approach to analyze the interactions between an attacker and a defender in a cyber-physical system (CPS) and develops effective defense strategies. In a CPS, the attacker launches cyber attacks on a number of nodes in the cyber layer, trying to maximize the potential damage to the underlying physical system while the system operator seeks to defend several nodes in the cyber layer to minimize the physical damage. Given that CPS attacking and defending is often a continual process, a zero-sum Markov game is proposed in this paper to model these interactions subject to underlying uncertainties of real-world events and actions. A novel model is also proposed in this paper to characterize the interdependence between the cyber layer and the physical layer in a CPS and quantify the impact of the cyber attack on the physical damage in the proposed game. To find the Nash equilibrium of the Markov game, we design an efficient algorithm based on value iteration. The proposed general approach is then applied to study the wide-area monitoring and protection issue in smart grid. Extensive simulations are conducted based on real-world data, and results show the effectiveness of the defending strategies derived from the proposed approach.

In this paper, we present a work-in-progress approach to detect integrity attacks to Smart Grids by analyzing the readings from smart meters. Our approach is based on process mining and time-evolving graphs. In particular, process mining is used to discover graphs, from the dataset collecting the readings over a time period, that represent the behaviour of a customer. The time-evolving graphs are then compared in order to detect anomalous behavior of a customer. To evaluate the feasibility of our approach, we have conducted preliminary experiments by using the dataset provided by the Ireland's Commission for Energy Regulation (CER).

Electronic power grid is a distributed network used for transferring electricity and power from power plants to consumers. Based on sensor readings and control system signals, power grid states are measured and estimated. As a result, most conventional attacks, such as denial-of-service attacks and random attacks, could be found by using the Kalman filter. However, false data injection attacks are designed against state estimation models. Currently, distributed Kalman filtering is proved effective in sensor networks for detection and estimation problems. Since meters are distributed in smart power grids, distributed estimation models can be used. Thus in this paper, we propose a diffusion Kalman filter for the power grid to have a good performance in estimating models and to effectively detect false data injection attacks.

Gaussian random attacks that jointly minimize the amount of information obtained by the operator from the grid and the probability of attack detection are presented. The construction of the attack is posed as an optimization problem with a utility function that captures two effects: firstly, minimizing the mutual information between the measurements and the state variables; secondly, minimizing the probability of attack detection via the Kullback-Leibler (KL) divergence between the distribution of the measurements with an attack and the distribution of the measurements without an attack. Additionally, a lower bound on the utility function achieved by the attacks constructed with imperfect knowledge of the second order statistics of the state variables is obtained. The performance of the attack construction using the sample covariance matrix of the state variables is numerically evaluated. The above results are tested in the IEEE 30-Bus test system.

Wireless Sensor Network is the combination of small devices called sensor nodes, gateways and software. These nodes use wireless medium for transmission and are capable to sense and transmit the data to other nodes. Generally, WSN composed of two types of nodes i.e. generic nodes and gateway nodes. Generic nodes having the ability to sense while gateway nodes are used to route that information. IoT now extended to IoET (internet of Everything) to cover all electronics exist around, like a body sensor networks, VANET's, smart grid stations, smartphone, PDA's, autonomous cars, refrigerators and smart toasters that can communicate and share information using existing network technologies. The sensor nodes in WSN have very limited transmission range as well as limited processing speed, storage capacities and low battery power. Despite a wide range of applications using WSN, its resource constrained nature given birth to a number severe security attacks e.g. Selective Forwarding attack, Jamming-attack, Sinkhole attack, Wormhole attack, Sybil attack, hello Flood attacks, Grey Hole, and the most dangerous BlackHole Attacks. Attackers can easily exploit these vulnerabilities to compromise the WSN network.

Advanced Metering Infrastructure (AMI) forms a communication network for the collection of power data from smart meters in Smart Grid. As the communication within an AMI needs to be secure, key management becomes an issue due to overhead and limited resources. While using public-keys eliminate some of the overhead of key management, there is still challenges regarding certificates that store and certify the public-keys. In particular, distribution and storage of certificate revocation list (CRL) is major a challenge due to cost of distribution and storage in AMI networks which typically consist of wireless multi-hop networks. Motivated by the need of keeping the CRL distribution and storage cost effective and scalable, in this paper, we present a distributed CRL management model utilizing the idea of distributed hash trees (DHTs) from peer-to-peer (P2P) networks. The basic idea is to share the burden of storage of CRLs among all the smart meters by exploiting the meshing capability of the smart meters among each other. Thus, using DHTs not only reduces the space requirements for CRLs but also makes the CRL updates more convenient. We implemented this structure on ns-3 using IEEE 802.11s mesh standard as a model for AMI and demonstrated its superior performance with respect to traditional methods of CRL management through extensive simulations.

Smart grid is the cornerstone of the modern urban construction, leading the development trend of the urban power industry. Wireless sensor network (WSN) is widely used in smart power grid. It mainly covers two routing methods, the plane routing protocol and the clustering routing protocol. Since the plane routing protocol needs to maintain a large routing table and works with a poor scalability, it will increase the overall cost of the system in practical use. Therefore, in this paper, the clustering routing protocol is selected to achieve a better operation performance of the wireless sensor network. In order to enhance the reliability of the routing security, the data fusion technology is also utilized. Based on this method, the rationality of the topology structure of the smart grid and the security of the node information can be effectively improved.

Smart Grid cybersecurity is one of the key ingredients for successful and wide scale adaptation of the Smart Grid by utilities and governments around the world. The implementation of the Smart Grid relies mainly on the highly distributed sensing and communication functionalities of its components such as Wireless Sensor Networks (WSNs), Phasor Measurement Units (PMUs) and other protection devices. This distributed nature and the high number of connected devices are the main challenges for implementing cybersecurity in the smart grid. As an example, the North American Electric Reliability Corporation (NERC) issued the Critical Infrastructure Protection (CIP) standards (CIP-002 through CIP-009) to define cybersecurity requirements for critical power grid infrastructure. However, NERC CIP standards do not specify cybersecurity for different communication technologies such as WSNs, fiber networks and other network types. Implementing security mechanisms in WSNs is a challenging task due to the limited resources of the sensor devices. WSN security mechanisms should not only focus on reducing the power consumption of the sensor devices, but they should also maintain high reliability and throughput needed by Smart Grid applications. In this paper, we present a WSN cybersecurity mechanism suitable for smart grid monitoring application. Our mechanism can detect and isolate various attacks in a smart grid environment, such as denial of sleep, forge and replay attacks in an energy efficient way. Simulation results show that our mechanism can outperform existing techniques while meeting the NERC CIP requirements.

Traditional security measures for large-scale critical infrastructure systems have focused on keeping adversaries out of the system. As the Internet of Things (IoT) extends into millions of homes, with tens or hundreds of devices each, the threat landscape is complicated. IoT devices have unknown access capabilities with unknown reach into other systems. This paper presents ongoing work on how techniques in sensor verification and cyber-physical modeling and analysis on bulk power systems can be applied to identify malevolent IoT devices and secure smart and connected communities against the most impactful threats.

False data injection attacks (FDIA) on state estimators are a kind of imminent cyber-physical security issue. Fortunately, it has been proved that if a set of measurements is strategically selected and protected, no FDIA will remain undetectable. In this paper, the metric Return on Investment (ROI) is introduced to evaluate the overall returns of the alternative measurement protection schemes (MPS). By setting maximum total ROI as the optimization objective, the previously ignored cost-benefit issue is taken into account to derive a realistic MPS for power utilities. The optimization problem is transformed into the Steiner tree problem in graph theory, where a tree pruning based algorithm is used to reduce the computational complexity and find a quasi-optimal solution with acceptable approximations. The correctness and efficiency of the algorithm are verified by case studies.

Smart Grids (SGs) are Critical Infrastructures (CI), which are responsible for controlling and maintaining the distribution of electricity. To manage this task, modern SGs integrate an Information and Communication Infrastructure (ICT) beside the electrical power grid. Aside from the benefits derived from the increasing control and management capabilities offered by the ICT, unfortunately the introduction of this cyber layer provides an attractive attack surface for hackers. As a consequence, security becomes a fundamental prerequisite to be fulfilled. In this context, the adoption of Systems Engineering (SE) tools combined with Modeling and Simulation (M&S) techniques represent a promising solution to support the evaluation process of a SG during early design stages. In particular, the paper investigates on the identification, modeling and assessment of attacks in SG environments, by proposing a model for representing attack scenarios as a combination of attack types, attack schema and their temporal occurrence. Simulation techniques are exploited to enable the execution of such attack combinations in the SG domain. Specifically, a simulator, which allows to assess the SG behaviour to identify possible flaws and provide preventive actions before its realization, is developed on the basis of the proposed model and exemplified through a case study.

Since the Information Networks are added to the current electricity networks, the security and privacy of individuals is challenged. This combination of technologies creates vulnerabilities in the context of smart grid power which disrupt the consumer energy supply. Methods based on encryption are against the countermeasures attacks that have targeted the integrity and confidentiality factors. Although the cryptography strategies are used in Smart Grid, key management which is different in size from tens to millions of keys (for meters), is considered as the critical processes. The Key mismanagement causes to reveal the secret keys for attacker, a symmetric key distribution method is recently suggested by [7] which is based on a symmetric key distribution, this strategy is very suitable for smart electric meters. The problem with this method is its vulnerability to impersonating respondents attack. The proposed approach to solve this problem is to send the both side identifiers in encrypted form based on hash functions and a random value, the proposed solution is appropriate for devices such as meters that have very little computing power.

Integration of information technologies with the current power infrastructure promises something further than a smart grid: implementation of smart cities. Power efficient cities will be a significant step toward greener cities and a cleaner environment. However, the extensive use of information technologies in smart cities comes at a cost of reduced privacy. In particular, consumers' power profiles will be accessible by third parties seeking information over consumers' personal habits. In this paper, a methodology for enhancing privacy of electricity consumption patterns is proposed and tested. The proposed method exploits digital connectivity and predictive tools offered via smart grids to morph consumption patterns by grouping consumers via an optimization scheme. To that end, load anticipation, correlation and Theil coefficients are utilized synergistically with genetic algorithms to find an optimal assembly of consumers whose aggregated pattern hides individual consumption features. Results highlight the efficiency of the proposed method in enhancing privacy in the environment of smart cities.

The collection of high frequency metering data in the emerging smart grid gives rise to the concern of consumer privacy. Anonymization of metering data is one of the proposed approaches in the literature, which enables transmission of unmasked data while preserving the privacy of the sender. Distributed anonymization methods can reduce the dependency on service providers, thus promising more privacy for the consumers. However, the distributed communication among the end-users introduces overhead and requires methods to prevent external attacks. In this paper, we propose four variants of a distributed anonymization method for smart metering data privacy, referred to as the Collaborative Anonymity Set Formation (CASF) method. The performance overhead analysis and security analysis of the variants are done using NS-3 simulator and the Scyther tool, respectively. It is shown that the proposed scheme enhances the privacy preservation functionality of an existing anonymization scheme, while being robust against external attacks.

With the rapid development of smart grid, smart meters are deployed at energy consumers' premises to collect real-time usage data. Although such a communication model can help the control center of the energy producer to improve the efficiency and reliability of electricity delivery, it also leads to some security issues. For example, this real-time data involves the customers' privacy. Attackers may violate the privacy for house breaking, or they may tamper with the transmitted data for their own benefits. For this purpose, many data aggregation schemes are proposed for privacy preservation. However, rare of them cares about both the data aggregation and fine-grained access control to improve the data utility. In this paper, we proposes a data aggregation scheme based on attribute decision tree. Security analysis illustrates that our scheme can achieve the data integrity, data privacy preservation and fine- grained data access control. Experiment results show that our scheme are more efficient than existing schemes.