NIST 800-53 REV 5 • SYSTEM AND COMMUNICATIONS PROTECTION
SC-4(2) — Multilevel or Periods Processing
Prevent unauthorized information transfer via shared resources in accordance with {{ insert: param, sc-04.02_odp }} when system processing explicitly switches between different information classification levels or security categories.
CMMC Practice Mapping
No direct CMMC mapping
NIST 800-171 Mapping
No direct NIST 800-171 mapping
Related Controls
No related controls listed
Supplemental Guidance
Changes in processing levels can occur during multilevel or periods processing with information at different classification levels or security categories. It can also occur during serial reuse of hardware components at different classification levels. Organization-defined procedures can include approved sanitization processes for electronically stored information.
Practitioner Notes
During multilevel or periods processing — where a system switches between handling data at different classification levels — shared resources must be sanitized according to approved procedures before the switch.
Example 1: Before switching a workstation from processing SECRET data to UNCLASSIFIED data, follow your approved sanitization procedure: clear memory, flush caches, and verify no residual classified data remains using approved tools.
Example 2: On shared printers that handle documents at multiple classification levels, configure the device to purge its internal memory and print queue completely between classification level changes, and display the current operating level on the printer console.