- State the rule: whether organizational portable storage may be used on external systems at all, and under what conditions when yes.
- Issue encrypted, organization-owned drives for the permitted cases and prefer managed transfer services over sneakernet wherever a network path exists.
3.1.21OFFICIAL STATEMENT BELOWDERIVED REQUIREMENTPENDING NIST SME REVIEW
3.1.21 — Portable storage on external systems
3.1 Access Control · NIST SP 800-171 Rev. 2 · The heading label is this site's navigational shorthand; the official language is the statement below.
Official requirement statement (verbatim)
Limit use of portable storage devices on external systems.
NIST SP 800-171 Rev. 2 — Protecting CUI in Nonfederal Systems ↗NIST SP 800-171A — Assessing Security Requirements for CUI ↗Independent interpretation
What this requirement is after
Your portable storage plugged into systems you do not control — a company USB drive in a hotel business center or a partner's machine — carries your data into environments with unknown hygiene. Limit when that is allowed at all, and put the data beyond casual reach when it is.
Across revisions
Withdrawn as a standalone slot in Rev. 3 (03.01.21); portable storage on external systems is carried inside Use of External Systems, 03.01.20.
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
- The written portable-storage rule covering use on external systems
- The register of issued encrypted drives, where portable storage is permitted
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 lands in Rev. 3
Provenance
Sources and review status
| Primary sources | NIST SP 800-171 Rev. 2 — Protecting CUI in Nonfederal Systems · NIST SP 800-171A — Assessing Security Requirements for CUI |
|---|---|
| Review status | Pending NIST SME review |
| Content version | 1.0 |
| Updated |