Software Defined Networks based Smart Grid Communication: A Comprehensive Survey

The current power grid is no longer a feasible solution due to ever-increasing user demand of electricity, old infrastructure, and reliability issues and thus require transformation to a better grid a.k.a., smart grid (SG). The key features that distinguish SG from the conventional electrical power grid are its capability to perform two-way communication, demand side management, and real time pricing. Despite all these advantages that SG will bring, there are certain issues which are specific to SG communication system. For instance, network management of current SG systems is complex, time consuming, and done manually. Moreover, SG communication (SGC) system is built on different vendor specific devices and protocols. Therefore, the current SG systems are not protocol independent, thus leading to interoperability issue. Software defined network (SDN) has been proposed to monitor and manage the communication networks globally. This article serves as a comprehensive survey on SDN-based SGC. In this article, we first discuss taxonomy of advantages of SDNbased SGC.We then discuss SDN-based SGC architectures, along with case studies. Our article provides an in-depth discussion on routing schemes for SDN-based SGC. We also provide detailed survey of security and privacy schemes applied to SDN-based SGC. We furthermore present challenges, open issues, and future research directions related to SDN-based SGC.Comment: Accepte

Electric Vehicles Charging Control based on Future Internet Generic Enablers

In this paper a rationale for the deployment of Future Internet based applications in the field of Electric Vehicles (EVs) smart charging is presented. The focus is on the Connected Device Interface (CDI) Generic Enabler (GE) and the Network Information and Controller (NetIC) GE, which are recognized to have a potential impact on the charging control problem and the configuration of communications networks within reconfigurable clusters of charging points. The CDI GE can be used for capturing the driver feedback in terms of Quality of Experience (QoE) in those situations where the charging power is abruptly limited as a consequence of short term grid needs, like the shedding action asked by the Transmission System Operator to the Distribution System Operator aimed at clearing networks contingencies due to the loss of a transmission line or large wind power fluctuations. The NetIC GE can be used when a master Electric Vehicle Supply Equipment (EVSE) hosts the Load Area Controller, responsible for managing simultaneous charging sessions within a given Load Area (LA); the reconfiguration of distribution grid topology results in shift of EVSEs among LAs, then reallocation of slave EVSEs is needed. Involved actors, equipment, communications and processes are identified through the standardized framework provided by the Smart Grid Architecture Model (SGAM).Comment: To appear in IEEE International Electric Vehicle Conference (IEEE IEVC 2014

Resilient communications in smart grids

Tese de mestrado, Segurança Informática, Universidade de Lisboa, Faculdade de Ciências, 2018As redes elétricas, algumas já centenárias, foram concebidas para uma realidade bastante diferente da actual. O facto de terem sido desenhadas para transportar e distribuir a energia de forma unidirecional, torna a infraestrutura rígida, causando problemas em termos de escalabilidade e dificulta a sua evolução. Conhecidas questões ambientais têm levado a que a geração de energia baseada em combustíveis fosseis seja substituída pela geração através de fontes de energia renováveis. Esta situação motivou a criação de incentivos ao investimento nas fontes de energia renováveis, o que levou a que cada vez mais consumidores apostem na microgeração. Estas alterações causaram uma mudança na forma como é feita a produção e distribuição de energia elétrica, com uma aposta crescente na interligação entre as várias fontes ao longo da infraestrutura, tornando a gestão destas redes uma tarefa extremamente complexa. Com o crescimento significativo de consumidores que também podem ser produtores, torna-se essencial uma coordenação cuidada na injeção de energia na rede. Este facto, aliado à crescente utilização de energia elétrica, faz com que a manutenção da estabilidade da rede seja um enorme desafio. As redes inteligentes, ou smart grids, propõem resolver muitos dos problemas que surgiram com esta alteração do paradigma de consumo/produção de energia elétrica. Os componentes da rede passam a comunicar uns com os outros, tornando a rede eléctrica bidirecional, facilitando assim a sua manutenção e gestão. A possibilidade de constante troca de informação entre todos os componentes que constituem a smart grid permite uma reação imediata relativamente às ações dos produtores e consumidores de energia elétrica. No entanto, com esta alteração de paradigma surgiram também muitos desafios. Nomeadamente, a necessidade de comunicação entre os equipamentos existentes nas smart grids leva a que as redes de comunicação tenham de cobrir grandes áreas. Essa complexidade aumenta quando a gestão necessita de ser feita ao nível de cada equipamento e não de forma global. Isto ´e devido ao facto de nas redes de comunicação tradicionais, o plano de controlo e o de dados estarem no mesmo equipamento, o que leva a que o seu controlo seja difícil e propício a erros. Este controlo descentralizado dificulta também a reorganização da rede quando ocorrem faltas pelo facto de não existir um dispositivo que tenha o conhecimento completo da rede. A adaptação rápida a faltas de forma a tornar a comunicação resiliente tem grande importância em redes sensíveis a latência como é o caso da smart grid, pelo que mecanismos eficientes de tolerância a faltas devem ser implementados. As redes definidas por software, ou Software Defined Networks (SDN), surgem como uma potencial solução para estes problemas. Através da separação entre o plano de controlo e o plano de dados, permite a centralização lógica do controlo da rede no controlador. Para tal, é necessário adicionar uma camada de comunicação entre o controlador e os dispositivos de rede, através de um protocolo como o Openflow. Esta separação reduz a complexidade da gestão da rede e a centralização lógica torna possível programar a rede de forma global, de modo a aplicar as políticas pretendidas. Estes fatores tornam a SDN uma soluçãoo interessante para utilizar em smart grids. Esta tese investiga formas de tornar a rede de comunicações empregue numa smart grid resiliente a faltas. Pelas vantagens mencionadas anteriormente, é usada uma solução baseada em SDN, sendo propostos dois módulos essenciais. O primeiro tem como objectivo a monitorização segura da rede, permitindo obter em tempo real métricas como largura de banda, latência e taxa de erro. O segundo módulo trata do roteamento e engenharia de tráfego, utilizando a informação fornecida pelo módulo de monitorização de forma a que os componentes da smart grid comuniquem entre si, garantindo que os requisitos das aplicações são cumpridos. Dada a criticidade da rede elétrica e a importância das comunicações na smart grid, os mecanismos desenvolvidos toleram faltas, quer de tipo malicioso, quer de tipo acidental.The evolution on how electricity is produced and consumed has made the management of power grids an extremely complex task. Today’s centenary power grids were not designed to fit a new reality where consumers can also be producers, or the impressive increase in consumption caused by more sophisticated and powerful appliances. Smart Grids have been prepared as a solution to cope with this problem, by supporting more sophisticated communications among all the components, allowing the grid to react quickly to changes in both consumption or production of energy. On the other hand, resorting to information and communication technologies (ICT) brings some challenges, namely, managing network devices at this scale and assuring that the strict communication requirements are fulfilled is a dauting task. Software Defined Networks (SDN) can address some of these problems by separating the control and data planes, and logically centralizing network control in a controller. The centralised control has the ability to observe the current state of the network from a vantage point, and programatically react based on that view, making the management task substantially easier. In this thesis we provide a solution for a resilient communications network for Smart Grids based on SDN. As Smart Grids are very sensitive to network issues, such as latency and packet loss, it is important to detect and react to any fault in a timely manner. To achieve this we propose and develop two core modules, a network monitor and a routing and traffic engineering module. The first is a solution for monitoring with the goal to obtain a global view of the current state of the network. The solution is secure, allowing malicious attempts to subvert this module to be detected in a timely manner. This information is then used by the second module to make routing decisions. The routing and traffic engineering module ensures that the communications among the smart grid components are possible and fulfils the strict requirements of the Smart Grid

A Software Defined Networking Architecture for DDoS-Attack in the storage of Multi-Microgrids

Multi-microgrid systems can improve the resiliency and reliability of the power system network. Secure communication for multi-microgrid operation is a crucial issue that needs to be investigated. This paper proposes a multi-controller software defined networking (SDN) architecture based on fog servers in multi-microgrids to improve the electricity grid security, monitoring and controlling. The proposed architecture defines the support vector machine (SVM) to detect the distributed denial of service (DDoS) attack in the storage of microgrids. The information of local SDN controllers on fog servers is managed and supervised by the master controller placed in the application plane properly. Based on the results of attack detection, the power scheduling problem is solved and send a command to change the status of tie and sectionalize switches. The optimization application on the cloud server implements the modified imperialist competitive algorithm (MICA) to solve this stochastic mixed-integer nonlinear problem. The effective performance of the proposed approach using an SDN-based architecture is evaluated through applying it on a multi-microgrid based on IEEE 33-bus radial distribution system with three microgrids in simulation results

Classifying resilience approaches for protecting smart grids against cyber threats

Smart grids (SG) draw the attention of cyber attackers due to their vulnerabilities, which are caused by the usage of heterogeneous communication technologies and their distributed nature. While preventing or detecting cyber attacks is a well-studied field of research, making SG more resilient against such threats is a challenging task. This paper provides a classification of the proposed cyber resilience methods against cyber attacks for SG. This classification includes a set of studies that propose cyber-resilient approaches to protect SG and related cyber-physical systems against unforeseen anomalies or deliberate attacks. Each study is briefly analyzed and is associated with the proper cyber resilience technique which is given by the National Institute of Standards and Technology in the Special Publication 800-160. These techniques are also linked to the different states of the typical resilience curve. Consequently, this paper highlights the most critical challenges for achieving cyber resilience, reveals significant cyber resilience aspects that have not been sufficiently considered yet and, finally, proposes scientific areas that should be further researched in order to enhance the cyber resilience of SG.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Funding for open access charge: Universidad de Málaga / CBUA