The industrial internet and Industrie 4.0 are driving the transformation of industrial assets into cyber-physical entities. The erstwhile air-gapped devices and operational domains are now being connected to business application systems over IP-based network infrastructure (Figure 5.3):
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Figure 5.3: Transition of industrial systems from unconnected to converged IT/OT model
Ubiquitous connectivity introduces new operational dynamics in OT environments. To adequately protect OT connectivity, we need to consider its key distinguishing aspects, as discussed in this section.