Sets out the appropriate requirements for the information security of operational technology (OT), with component-spanning, conceptual and architectural security requirements. In Edition 2023 the Baustein carries 24 requirement numbers, 23 of them live: 4 Basis requirements (B, MUSS, to be fulfilled first and without exception), 13 Standard requirements (S, SOLLTE) and 6 requirements for elevated protection needs (H), with 1 number withdrawn (ENTFALLEN) and kept for stable numbering. It is applied to the information domain as a whole (overarching aspects) in modelling order R2. The requirements property on this node lists every requirement by number, title, level and responsible role, so a requirement is cited as IND.1.A<n>.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.