- In practice this means reliable NTP everywhere, including the appliances and hypervisors whose clocks drift most; domain-joined machines and cloud services largely handle themselves.
- Standardize on UTC in aggregation and let display layers localize — mixed local-time logs are a permanent investigation tax.
- Confirm the granularity platforms actually record; one-second precision is typically available and defensible as the defined parameter.
03.03.07OFFICIAL TITLEPENDING NIST SME REVIEW
03.03.07 — Time Stamps
03.03 Audit and Accountability · NIST SP 800-171 Rev. 3
Independent summary of the official requirement
Requires using internal system clocks to generate time stamps for audit records, recorded to an organization-defined granularity of time measurement and expressed in Coordinated Universal Time, with a fixed local offset from UTC, or with the local offset included in the time stamp.
Rev. 3 requirement text is multi-part and parameterized with organization-defined values, so this site summarizes rather than reproduces it. The summary is independent — read the official publication for the binding wording.
NIST SP 800-171 Rev. 3 — Protecting CUI in Nonfederal Systems ↗NIST SP 800-171A Rev. 3 — Assessing Security Requirements for CUI ↗Independent interpretation
What this requirement is after
Correlating events across systems is arithmetic on timestamps; if clocks disagree, the sequence of an attack cannot be reconstructed. Records carry timestamps at a defined precision, in UTC or with a known offset, from clocks the systems themselves keep.
Across revisions
Reframed from 3.3.7: Rev. 2's compare-and-synchronize-with-an-authoritative-source phrasing becomes internal clocks generating time stamps at an organization-defined granularity, in UTC or with a known local offset.
Mapped practices
Brilliant at the Basics practices that support this requirement
No practice maps to this requirement — deliberately.
The campaign’s twenty practices are a priority list, not a control catalog, and none of them works this requirement’s substance directly. It still applies to you if it is in your contract’s scope: address it through your own implementation and the related artifacts below, and treat the absence of a mapping here as honesty, not permission to skip it.
Doing the work
Implementation considerations and evidence
- Time synchronization configuration across system types, including appliances
- Sampled records from separate sources showing consistent, comparable timestamps
Artifacts
Templates and worksheets with a mapped relationship
No artifact in the library names this requirement yet. The library index groups everything by category and practice.
The other revision
Where this came from in Rev. 2
Provenance
Sources and review status
| Primary sources | NIST SP 800-171 Rev. 3 — Protecting CUI in Nonfederal Systems · NIST SP 800-171A Rev. 3 — Assessing Security Requirements for CUI |
|---|---|
| Review status | Pending NIST SME review |
| Content version | 1.0 |
| Updated |