ABSTRACT
Introduction Obsolescence in the industrial control system has a significantly different meaning than in the enterprise network environment. Most newly installed industrial control systems are obsolete by normal IT standards. An enterprise computer system has a 3-5-year life cycle, but industrial control systems previously had a 15-30-year life cycle. Changes in computers and operating systems (OSs) and the impact of cybersecurity threats have forced changes to the industrial control system life cycle.
