Open Architecture Supervisory Control and Data Acquisition System: Security Enhancement with Defense-in-Depth Strategies

Abstract

The function of the Supervisory Control and Data Acquisition (SCADA) System is to monitor and control physical processes in real time in a geographically spread environment. SCADA system is applied in supervision and control of devices action in electricity distribution, transmission; oil and gas pipelines, water distribution, and traffic lights among other critical infrastructure. Deregulation of electricity sector in Nigeria provides private independent power producers' access to the Transmission Company of Nigeria network and hence transforms the closed (isolated) SCADA System of the TCN to an open architecture SCADA System. An open architecture SCADA System is susceptible to threats and attacks within and without with catastrophic impact on the efficiency of the critical infrastructure it is designed to monitor and control. Using empirical method, the type of threats and level of exposure of the TCN SCADA System were examined. The investigation revealed that TCN SCADA System is majorly protected against internal threats. Hence security enhancement through Defense-in-depth strategies that would provide wide arrays of security were proposed and briefly elaborated on for successful implementation.