SA-9(2) External system services | identification of functions, ports, protocols, and services
What the standard requires
Require providers of the following external system services to identify the functions, ports, protocols, and other services required for the use of such services: [external system services].
Quoted verbatim from NIST SP 800-53 Rev 5 (OSCAL catalog), which is in the public domain.
Cross-framework mappings
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