CIE Principle 3: Secure information architecture

The secure information architecture principle identifies data elements and command paths that directly control high-consequence physical functions. If an adversary can alter these data values, they can influence or issue commands that change how the system interacts with the physical environment, potentially leading to unsafe states or catastrophic outcomes. This principle recognizes certain safety-critical data elements due to the physical effects they can produce if manipulated and prioritizes architectural protections around them to prevent harmful system behavior.

Once identified, these data flows can be prioritized for additional monitoring, both digitally and through independent sensing (e.g., analog sensors). Validation schemes and heuristics can then be developed to detect anomalous data and limit its ability to cause undesired impacts. Where feasible, engineered controls should prevent out-of-bounds data from being accepted or acted upon by the system.