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AC-04(27) Redundant/Independent Filtering Mechanisms

NIST SP 800-53 (controls) 5.2.0 against 5.2.0
All changes in this version
unchanged AC part of AC-4

Title

Redundant/Independent Filtering Mechanisms

Control

When transferring information between different security domains, implement content filtering solutions that provide redundant and independent filtering mechanisms for each data type.

Discussion

Content filtering is the process of inspecting information as it traverses a cross-domain solution and determines if the information meets a predefined policy. Redundant and independent content filtering eliminates a single point of failure filtering system. Independence is defined as the implementation of a content filter that uses a different code base and supporting libraries (e.g., two JPEG filters using different vendors’ JPEG libraries) and multiple, independent system processes.

Assessment objective

AC-04(27) when transferring information between security domains, implemented content filtering solutions provide redundant and independent filtering mechanisms for each data type.

STIG rules that implement this control 0

No followed STIG rule cites a CCI indexed to this control (CCI list 2026-07-14).