The control system must be able to separate, logically, its own networks from networks that are not part of it, and its critical networks from its other networks. RE 1 requires the same separation to be physical; RE 2 requires independence from networks outside the control system, so network services keep working without them; RE 3 requires critical networks to be isolated both logically and physically.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.