Project Record

Security diagram index

An archival format for threat models, trust boundaries, assumptions, and revision history.

The security diagram index treats diagrams as documents with provenance. Each drawing records not only the current model, but the assumptions and revisions that shaped it.

Boundary

Every boundary in the diagram needs a reason to exist. Where the reason is weak, the drawing becomes useful: it reveals the part of the system that deserves closer attention.

Revision

The index keeps older assumptions visible. That history helps separate intentional design from inherited convenience.