ABSTRACT
Obsolescence in industrial control systems 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 three-to five-year lifecycle. An industrial control system has a 15-30-year lifecycle. Even today with Microsoft Windows 7 as an aging operating system, Windows 8 will be out within the next 12 months, a large segment of the currently operating industrial control systems are running Microsoft Windows 2000, 2003, or XP. Some industries continue to use much older systems.
