# SC-45(2) — Secondary Authoritative Time Source

- **Control ID:** SC-45(2)
- **Family:** [SC](/md/families/SC.md)
- **Baselines:** No content available.
- **Enhancement of:** [SC-45](/md/controls/SC-45.md)

## Description

Identify a secondary authoritative time source that is in a different geographic region than the primary authoritative time source; and Synchronize the internal system clocks to the secondary authoritative time source if the primary authoritative time source is unavailable.

## Discussion

It may be necessary to employ geolocation information to determine that the secondary authoritative time source is in a different geographic region.

## Implementation guidance

No content available.

## CSF 2.0 subcategories

No content available.

## Related controls

No content available.

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Derived from official NIST publications (NIST SP 800-53 Rev 5 and NIST CSF 2.0). nistcontrols.com is not affiliated with NIST.