Cyber-Physical Systems Security—A Survey <s> C. Smart Grids Challenges 1) Two-Way Communication: <s> This article has given a broadbrush description of issues related to smart-grid security. Designing solutions in at this stage, before widespread deployment, would be beneficial; in some cases solutions exist, whereas in others research investments will be needed. Several open questions about goals still require discussion, especially around such topics as how (and how much) privacy can be supported. <s> BIB001 </s> Cyber-Physical Systems Security—A Survey <s> C. Smart Grids Challenges 1) Two-Way Communication: <s> Household smart meters that measure power consumption in real-time at fine granularities are the foundation of a future smart electricity grid. However, the widespread deployment of smart meters has serious privacy implications since they inadvertently leak detailed information about household activities. In this paper, we show that even without a priori knowledge of household activities or prior training, it is possible to extract complex usage patterns from smart meter data using off-the-shelf statistical methods. Our analysis uses two months of data from three homes, which we instrumented to log aggregate household power consumption every second. With the data from our small-scale deployment, we demonstrate the potential for power consumption patterns to reveal a range of information, such as how many people are in the home, sleeping routines, eating routines, etc. We then sketch out the design of a privacy-enhancing smart meter architecture that allows an electric utility to achieve its net metering goals without compromising the privacy of its customers. <s> BIB002 </s> Cyber-Physical Systems Security—A Survey <s> C. Smart Grids Challenges 1) Two-Way Communication: <s> In this paper, we present a distributed incremental data aggregation approach, in which data aggregation is performed at all smart meters involved in routing the data from the source meter to the collector unit. With a carefully constructed aggregation tree, the aggregation route covers the entire local neighborhood or any arbitrary set of designated nodes with minimum overhead. To protect user privacy, homomorphic encryption is used to secure the data en route. Therefore, all the meters participate in the aggregation, without seeing any intermediate or final result. In this way, our approach supports efficient data aggregation in smart grids, while fully protecting user privacy. This approach is especially suitable for smart grids with repetitive routine data aggregation tasks. <s> BIB003 </s> Cyber-Physical Systems Security—A Survey <s> C. Smart Grids Challenges 1) Two-Way Communication: <s> We present a generic yet practical framework for assessing security risks to cyber-physical systems (CPSs). Our framework can be used to benchmark security risks when information is less than perfect, and interdependencies of physical and computational components may result in correlated failures. Such environments are prone to externalities, and can cause huge societal losses. We focus on the risks that arise from interdependent reliability failures (faults) and security failures (attacks). We advocate that a sound assessment of these risks requires explicit modeling of the effects of both technology-based defenses and institutions necessary for supporting them. Thus, we consider technology-based security defenses grounded in information security tools and fault-tolerant control in conjunction with institutional structures. Our game-theoretic approach to estimating security risks facilitates more effective defenses, especially against correlated failures. <s> BIB004 </s> Cyber-Physical Systems Security—A Survey <s> C. Smart Grids Challenges 1) Two-Way Communication: <s> The Smart Grid, generally referred to as the next-generation power system, is considered as a revolutionary and evolutionary regime of existing power grids. More importantly, with the integration of advanced computing and communication technologies, the Smart Grid is expected to greatly enhance efficiency and reliability of future power systems with renewable energy resources, as well as distributed intelligence and demand response. Along with the silent features of the Smart Grid, cyber security emerges to be a critical issue because millions of electronic devices are inter-connected via communication networks throughout critical power facilities, which has an immediate impact on reliability of such a widespread infrastructure. In this paper, we present a comprehensive survey of cyber security issues for the Smart Grid. Specifically, we focus on reviewing and discussing security requirements, network vulnerabilities, attack countermeasures, secure communication protocols and architectures in the Smart Grid. We aim to provide a deep understanding of security vulnerabilities and solutions in the Smart Grid and shed light on future research directions for Smart Grid security. <s> BIB005 </s> Cyber-Physical Systems Security—A Survey <s> C. Smart Grids Challenges 1) Two-Way Communication: <s> The electricity industry is now at the verge of a new era—an era that promises, through the evolution of the existing electrical grids to smart grids, more efficient and effective power management, better reliability, reduced production costs, and more environmentally friendly energy generation. Numerous initiatives across the globe, led by both industry and academia, reflect the mounting interest around not only the enormous benefits but also the great risks introduced by this evolution. This paper focuses on issues related to the security of the smart grid and the smart home, which we present as an integral part of the smart grid. Based on several scenarios, we aim to present some of the most representative threats to the smart home/smart grid environment. The threats detected are categorized according to specific security goals set for the smart home/smart grid environment, and their impact on the overall system security is evaluated. A review of contemporary literature is then conducted with the aim of presenting promising security countermeasures with respect to the identified specific security goals for each presented scenario. An effort to shed light on open issues and future research directions concludes this paper. <s> BIB006
One of the distinguishing features of smart grids is the two-way communication, thanks to the advanced metering infrastructure (AMI). Unlike the power grid, AMI allows smart meters attached to consumers' houses, that are easily accessible by physical attackers, to communicate with utility companies. This raises a new challenge to secure these devices BIB001 . 2) Access Control Mechanisms: Due to smart grids' enormous geographical coverage, in addition to the large number of stakeholders, appropriate access control mechanisms are needed BIB004 . Every possible access to smart grids' network, data, or devices must be controlled and managed. In addition, during emergency, access control mechanisms need to have enough flexibility to give appropriate privileges for the appropriate parties. 3) Privacy Concerns: As consumers' data has become a significant part of the smart grids' traffic, privacy concerns have become a great challenge. Not only should consumers' data be encrypted, but anonymization techniques are also desired to prevent inference and other attacks from deducing patterns from the encrypted data to reveal private information BIB006 , BIB002 . Some cryptographic-based solutions have been proposed. Li et al. BIB003 proposed a homomorphic encryption mechanism to protect consumers' privacy while maintaining low overhead on smart grids' traffic. However, such an approach does not prevent an attacker from participating in the data aggregation as a smart meter by injecting false data or impersonating a legitimate smart meter BIB005 . Therefore, designing mechanisms that both encrypt and aggregate data securely is a pressing challenge BIB005 .