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 communi-
cation protocols and architectures in the Smart Grid. We aim to provide a deep understand-
ing of security vulnerabilities and solutions in the Smart Grid and shed light on future
research directions for Smart Grid security.