Improving Security for SCADA Control Systems

The continuous growth of cyber security threats and attacks including the increasing sophistica-tion of malware is impacting the security of critical infrastructure, industrial control systems, and Supervisory Control and Data Acquisition (SCADA) control systems. The reliable operation of modern infrastructures depends on computerized systems and SCADA systems. Since the emer-gence of Internet and World Wide Web technologies, these systems were integrated with business systems and became more exposed to cyber threats. There is a growing concern about the security and safety of the SCADA control systems. The Presidential Decision Directive 63 document es-tablished the framework to protect the critical infrastructure and the Presidential document of 2003, the National Strategy to Secure Cyberspace stated that securing SCADA systems is a na-tional priority. The critical infrastructure includes telecommunication, transportation, energy, banking, finance, water supply, emergency services, government services, agriculture, and other fundamental systems and services that are critical to the security, economic prosperity, and social well-being of the public. The critical infrastructure is characterized by interdependencies (physi-cal, cyber, geographic, and logical) and complexity (collections of interacting components). Therefore, information security management principles and processes need to be applied to SCADA systems without exception. Critical infrastructure disruptions can directly and indirectly affect other infrastructures, impact large geographic regions, and send ripples throughout the na-tional and global economy. For example, under normal operating conditions, the electric power infrastructure requires fuels (natural gas and petroleum), transportation, water, banking and fi-nance, telecommunication, and SCADA systems for monitoring and control. In this paper, we provide an analysis of key developments, architecture, potential vulnerabilities, and security concerns including recommendations toward improving security for SCADA control systems. We discuss the most important issues concerning the security of SCADA systems in-cluding a perspective on enhancing security of these systems. We briefly describe the SCADA architecture, and identify the attributes that increase the complexity of these systems including the key developments that mark the evolution of the SCADA control systems along with the growth of potential vulnerabilities and security concerns. Then, we provide recommendations toward an enhanced security for SCADA control systems. More efforts should be planned on reducing the vulnerabilities and improving the security operations of these systems. It is necessary to address not only the individual vulnerabiltiies, but the breadth of risks that can interfere with critical operations. We describe key requirements and fea-tures needed to improve the security of the current SCADA control systems. For example, in assessing the risk for SCADA systems, use of general meth-ods for risk analysis including specific conditions and characteristics of a con-