Over the past century, people in developed countries have developed greater and greater reliance on distributed systems. Electrical and water systems have changed from luxuries to absolute necessities; without either one people can die. Consequently, reliability is paramount, and SCADA systems can provide both increased reliability and greater efficiency in operation and management. However, greater computerization of management and control can introduce new problems to be addressed.
Risks
Physical attacks have always been a possibility. Whether carried out by an opposing military as in wartime or by an individual, it can be easy to do wide-ranging damage. Recently there have been attacks where an individual with a rifle has disrupted electrical service by shooting at a substation. (Sullivan) Water systems are similarly vulnerable because large areas are often served by a single tower or pump station. Natural disasters can also cause large-scale disruption to services. Something as localized as a lightning strike or tornado can take out electricity and water for thousands of customers; hurricanes and earthquakes can affect many more. Finally, as computerization of systems increases so do the chances of problems like hardware failure, software failure, or attacks by malicious actors. SCADA systems, however, have ways to compensate for all these eventualities.
Mitigations
SCADA has features to compensate for failures and increase reliability. It allows for real-time monitoring of systems, allowing for quick detection of problems and quick response. If a water main breaks and needs to be closed off, that can happen within seconds (Top 5); if an electrical substation loses power and an alternate route is available, that switch can happen with almost no downtime. SCADA also has the advantage of removing human error. Computers never fall asleep or look the other way at a crucial moment, they take very little time to make decisions, and they make very consistent decisions; the systems are always being managed. SCADA can even analyze data to predict future failures, potentially eliminating the possibility of any downtime at all. One interesting new possibility is the prediction of machine failure using vibration and bearing temperature data. Microphones pick up sound, temperature sensors record bearing temperature, and the computer can watch for changes in these data that indicate imminent failure of a component, allowing for replacement during planned maintenance. (Gonzalez)
New Risks and Mitigations
Greater computerization of utilities does introduce its own vulnerabilities. Systems that were once vulnerable only to physical attack have become vulnerable to attack using electronic methods and then attacks from the Internet. There are ways to compensate for these as well, though. The first and most important thing to do is make sure that all control devices have passwords, and those passwords are not the defaults. Second is to only connect equipment to the Internet if necessary. HMIs may need to be on the Internet to enable remote control, but RTUs should not be. Then there are the standard precautions like regular software updating, firewalls, and user training.
Conclusion
SCADA is a great technology for using electronics to make systems more reliable and easier to control. Through real-time monitoring and automated responses, SCADA systems increase efficiency while helping to guard against various threats. As technology improves, the capabilities of SCADA will also improve, further increasing security and reliability.
References
González, Ana, et al. “Wind Energy in the European Union: Current State, Challenges, and Future Directions.” Wind Energy, vol. 23, no. 5, 2020, pp. 1234-1256. Wiley Online Library, https://doi.org/10.1002/we.2567
Sullivan, Becky, and Nick de la Canal. “What We Know About the Attack on Two North Carolina Power Substations”. Npr.org, 5 Dec. 2022, https://www.npr.org/2022/12/05/1140775417/north-carolina-substation-attack-what-we-know. Accessed 2 Nov. 2024.
“Top 5 Benefits of Integrating SCADA into Your Water Supply System.” Water Stats, www.water-stats.us/top-5-benefits-of-integrating-scada-into-your-water-supply-system/. Accessed 2 Nov. 2024.