Purdue model
IT/OT layering model underlying segmentation design.
The reference layering enterprise (Level 4–5) through operations (Level 3), supervision (Level 2), control (Level 1), and physical process (Level 0), with a DMZ between IT and OT. A starting sketch for segmentation, per ISA-95 concepts.
See also: ISA-95 · Industrial DMZ · Zones and conduits