AC-4(27) Redundant/Independent Filtering Mechanisms
Control enhancement of AC-4 Information Flow Enforcement
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.
Need AC-4(27) implemented and evidenced?
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