Boundary analysis

Drawing the boundary shows which parts of a device or its environment the manufacturer is responsible for securing. Everything crossing the boundary becomes an interface to analyze in the threat model.

the process of uniquely assigning information resources to an information system, which defines the security boundary for that system.

FDA guidance: Cybersecurity in Medical Devices: Quality Management System Considerations and Content of Premarket Submissions (February 2026), Appendix 5, Terminology