Traditionally, power grid architectures were standalone systems that consisted of proprietary protocols traversing legacy hardware and software systems (Li et al., 2012). Power grid automation systems using this type of architecture carried high operating costs that power companies found to be inefficient over time (Kuder et al., 2010). Due to this inefficiency, power companies began to integrate the operation of power grid automation systems into public networks. This integration served its purpose of reducing operating cost, but significantly increased the power grids exposure to cyber-attacks (Kuder et al., 2010). Recent discoveries that hackers have inserted software into the US electrical grid, allowing the grid to be disrupted at a later date from a remote location, clearly demonstrates the fact that the utility infrastructure is quite vulnerable and that its overall mission of serving the population could be severely compromised as a result of a cyber-attack (Li et al., 2012). The power grid uses dedicated lines with Inter Control Center Protocols (ICCP) and IP based LAN protocols to communicate between corporate and control centers (Kuder et al., 2010). Communication between the control center and substations is generally performed using the distributed network protocol (DNP) as well as wireless technology. This complicated means of communication between links makes power grid automation systems vulnerable to cyber-attacks. The vulnerabilities can be broken down into
