Having worked on plenty of industrial and other control systems I can safely say security on the systems is generally very poor. The vulnerabilities have existed for years but are just now getting attention. This is a problem that doesn't really need a bunch of new legislation. It's an education / resource issue. The existing methods that have been used for years with reasonable success in the IT industry can 'fix' this problem.
Industrial Controls systems are normally only replaced when they are so old that parts can no longer be obtained. PC's started to be widely used as operator interfaces about the time Windows 95 came out. A lot of those Win95 boxes are still running and have been connected to the network over the years.
And... if you can destroy a pump by turning it off and on too often then somebody engineered the control and drive system incorrectly. Operators (and processes) do stupid things all the time. As the control systems engineer your supposed to deal with that so that things don't go boom.
-- Mark Radabaugh Amplex
mark@amplex.net 419.837.5015
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There are still industrial control machines out there running MS-DOS. As you said not replaced until you can't get parts anymore. Chuck