Improving operational security for web-based distributed control systems in wastewater management

Traditional industrial systems have been designed to ne intrinsically safe by isolating their monitoring and control network. Considering the possible impact of a security attack, many plants today still choose to use this method to ensure maximum protection. At the same time, a separate trend observed in highly distributed applications like water management systems, is to centralize more local SCADA sites, into a Regional Control Center (RCC). This allows more efficient operation of existing resources and even integration with high level applications like water network modelling and simulation tools. Typical network include Ethernet and GSM communication. In order to benefit most from the implementation of plant-wide applications with reduced operating costs, increased flexibility and availability we need to address correctly the security aspects. This paper presents a methodology for improving operational security in a wastewater treatment plant and exemplifies its implementation in a specific application.