A cryptographic boundary is
|“||an explicitly defined contiguous perimeter that establishes the physical bounds of a cryptographic module and contains all the hardware, software, and/or firmware components of a cryptographic module.||”|
|“||a logical container where all the relevant security components of a control system that employ cryptography reside. It includes the processing hardware, data, and memory as well as other critical components.||”|
- Unified Capabilities, Framework 2013, App. C, at C-10 (full-text). See also NIST, FIPS 140-1, at 13.
- Catalog of Control Systems Security: Recommendations for Standards Developers (Apr. 2011 version), at 162.