LITMIR.BIZ

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Centralized and distributed generation Decisions driven by cost Decisions driven by cost and sustainability Vulnerable to catastrophic events Contained events Limited energy choices Personalized energy options Vulnerable to new threats Inherently secure against threats

The extensive digital technologies that enable significant improvements to new energy systems also increase the attack surface for cyber intrusion. The increasingly significant role of information systems and growing dependence on managing the power flow (generation, transmission, and distribution), markets, customers, financial, and trade needs call for special efforts to foster confidence in computing systems and information systems for business and industrial applications. Since the emergence of Internet and World Wide Web technologies, the control systems were integrated with the business and IT systems and became more exposed to cyber threats. Although specific threats target control systems and intelligent devices, these systems are also exposed to the same cyberspace threats as any business system because they share the common vulnerabilities with the traditional IT systems.

1.7 Critical Smart Grid Systems

      The availability and reliability of computing and information systems for business and power grid applications are dependent on the secure operations of ICSs and other infrastructures. The following sections include a brief introduction of key systems and security concerns. Any attack on any of these systems can propagate on other systems too.

      1.7.1 Industrial Control Systems

      A control system is a device or set of devices to manage, command, direct, or regulate the behavior of other devices or systems. ICSs are typically used to operate the infrastructure in industries such as electrical, water, oil and gas, and chemical including experimental and research facilities such as nuclear fusion laboratories. SCADA systems, DCS, and other smaller control system configurations including skid‐mounted PLC are often found in the industrial sectors and critical infrastructures. These are also known under a general term, ICS. The reliable operation of modern infrastructures depends on computerized systems and SCADA systems.

      In the past, control systems were isolated from other IT systems. Connection to the Internet is new (early 1990s) and debatable among specialists. Many experts agree that exposing control systems to the public PSTN and Internet carries unacceptable risk. However, even without any connection to the Internet, these systems are still vulnerable to external or internal attackers that can exploit vulnerabilities in private communication network and protocol, software such as operating systems, custom and vendor software, data storage software, databases, and applications.

      Control systems are exposed to the same cyberspace threats like any business system because they share the common vulnerabilities with the traditional IT systems. In complex interactive systems like Smart Grid whose elements are tightly coupled, likelihood of targeted attack as well as failures from erroneous operations and natural disasters and accidents is quite high. Vulnerabilities and attacks could be at different levels – software controlling or controlled device, application, storage, data access, LAN, enterprise, private communication links, and public PSTN and Internet‐based communications.

      1.7.2 SCADA Systems

      SCADA system is a common process automation system that is used to gather data from sensors and instruments located at remote sites and to transmit data at a central site for either control or monitoring purposes. The collected data is usually viewed on one or more SCADA host computers located at the central or master site. Based on information received from remote stations, automated or operator‐driven supervisory commands can be pushed to remote station control devices, which are often referred to as field devices. Generally, a SCADA system includes the following components:

       Instruments that sense process variables.

       Operating equipment connected to instruments.

       Local processors that collect data and communicate with the site’s instruments and operating equipment called PLC, remote terminal unit (RTU), intelligent electronic device (IED), or programmable automation controller (PAC).

       Short‐range communications between local processors, instruments, and operating equipment.

       Host computers as central point of human monitoring and control of the processes, storing databases, and display of statistical control charts and reports. Host computers are also known as master terminal unit (MTU), the SCADA server, or a PC with human–machine interface (HMI).

       Long‐range communications between local processors and host computers using wired and/or wireless network connections.

Figure 1.22 shows a typical SCADA system with HMI installed in a control center and connected via communication network to monitored field sites.

Figure 1.22 SCADA general diagram.

      Source: [NIST SP800‐82r2].

      Public Domain.

      SCADA system is a category of control systems used to monitor or control processes such as chemical, transport, water supply, power generation and distribution, and gas and oil supply. A control system is a device or set of devices to manage, command, direct, or regulate the behavior of other devices or systems. However, SCADA is not a full control system, but rather focuses on the supervisory level. Usually, SCADA systems involve a human‐in‐the‐loop control and decision‐making processes.

      The architecture of a SCADA system consists of one of more MTUs that are used by engineers in a control station to monitor and control a large number of RTUs located in field or industrial plants. An MTU is a general‐purpose computer or server running SCADA utility programs and RTUs are generally small dedicated devices designed for rough field or industrial environment. One or more SCADA MTUs retrieve real‐time analog and status data from RTUs, store to data historian, and analyze the data. MTUs automatically send control commands to the RTUs or enable the engineers to do so manually.

      Vulnerability discovery techniques and appropriate engineering activities are required to ensure security, reliability, and safety of plants that use SCADA control systems.

      These systems evolved from static to dynamic systems. The increased connectivity to Internet and mobile device technology has also a major impact on control system architectures. Modern products are often based on component architectures using commercial off‐the‐shelf (COTS) product elements as units. Security and safety of the SCADA control systems in terms of vulnerabilities, lack of protection, and awareness are discussed in [Hentea 2007]. Information security management principles and processes need to be applied to SCADA systems without exception.

      1.7.3 Energy Management Systems

      Although not unique definition is used for EMS, one definition is more common:

      Computer systems used by operators of electric to monitor, control, and optimize the performance of the power grid (generation, transmission, distribution).

      The functionality of any EMS is supported by a combination of two systems:

       SCADA system for monitoring and control.

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