A qualitative identification method for information assets of substation automation systems

Information security risk assessment combined with power control process is not a properly resolve problem, the lack of asset identification method accord with characteristics of power information systems is one of the main factors. Network-based substation automation systems (SAS) are typical power information systems, based on the analysis of difficulties on asset identification, a complete information asset identification method is introduced from three aspects, includes asset classification, task identification, and asset valuation. In the asset classification, combined with the IEC 61850 standard, a structured asset model is defined based on association of actual intelligent electronic devices and virtual logical nodes. In the task identification, take functions of substation automation as the object of task, the concept of function graph is defined to reflect the logical relations between functions and assets, as well as the logical relation between the assets. In the asset valuation, two levels of asset value include function level and substation level, are defined to quantify the information security properties of assets and the effects of possible accidents. Finally, an evaluation instance is constructed from IEC 61850 standard, the proposed method is applicable to asset identification of network-based SAS.