Introduction

It is well known that the existing power grid represents a critical asset essential for the functioning and welfare of modern society. A movement to a smarter power grid promises to enable greater energy delivery, reliability, and efficiency. It also represents a critical foundation for reducing greenhouse gas emissions and transitioning to a lowcarbon economy. The evolution from today's power grid to a smarter grid is only possible through greater dependency on information technology.

There are currently many working definitions for a smart grid. The North American Reliability Corporation (NERC) has defined the smart grid as ‘the integration of realtime monitoring, advanced sensing, and communications, utilizing analytics and control, enabling the dynamic flow of both energy and information to accommodate existing and new forms of supply, delivery, and use in a secure and reliable electric power system, from generation source to end-user’. The movement towards cyber-enabled power systems increases the risk of attacks on information devices and communications systems for several reasons.

From an engineering perspective, there is increased opportunity for cyber attack in a smart grid because of the greater reliance on distributed advanced metering infrastructure (AMI), intelligent electronic devices (IEDs), and wireless and/or off-the-shelf communications components and systems. Such cyber infrastructure increases system connectivity and autonomous decision-making by employing standardized information protocols that often have (or will have in the future) publicly documented vulnerabilities. Motivations for attack also abound.