Cybersecurity for Industrial Control Systems

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IntroDuCtIon

(air-gapped), and use industrial protocols directly at layer 2 of the net-

work stack, such as Modbus or Probus. Reports from the ICS envi-

ronment used for management purposes would have to be generated

on the ICS devices and manually transported to the corporate net-

work devices. Alternately, raw data could be extracted from the ICS

devices to be input into corporate devices for processing and report-

ing. e safety instrumented systems were also air-gapped from both

the ICS and the corporate networks. e ICS networks have always

had logical connections to the outside world in the form of modem

banks used for remote access by ...