
Boundary Diagrams That Satisfy a NIST 800-171 Assessment
Assessors accept boundary diagrams that show the true system boundary, key internal boundaries, and CUI flows, supported by evidence that matches the SSP and CMMC scoping.

Assessors accept boundary diagrams that show the true system boundary, key internal boundaries, and CUI flows, supported by evidence that matches the SSP and CMMC scoping.

NIST published SP 800-171 Revision 3 in May 2024, but DoD contracts and CMMC assessments still point to Revision 2; use Rev 2 for assessments now and prepare your program to absorb Rev 3’s structure, alignment with SP 800-53 Rev 5, and organization-defined parameters.

NIST expanded and reshaped assessment objectives in SP 800-171A Rev. 3, which changes evidence planning, sampling, and scoring for contractors that handle CUI.

Continuous monitoring under NIST SP 800-171 means you operate, measure, and improve control performance with automation and human review on a defined cadence, then produce evidence that shows that operation over time.

NIST SP 800-171 Rev 3 turns many requirements into organization-defined parameters that you must set, document, and defend, and DoD now assigns specific values for a subset that contractors must use.

Mobile endpoints enter the CUI boundary as soon as users access or store CUI on them, so you need clear scope, NIST SP 800-171 controls applied to iOS and Android, and enforceable MDM or MAM policies before you allow mobile access.