Isolate ICS networks from any untrusted networks, especially the Internet; lock down all unused ports and turn off all unused services. Allow real-time external connectivity only where there is a defined business or control requirement; use one-way optical separation (data diode) where one-way communication suffices, and a single restricted port if bidirectional communication is necessary.
This control maps to 2 controls across 2 other frameworks. If you already hold one of them, the evidence you collected for it is the starting point here rather than new work.
Every mapping shown was judged rather than inferred from wording similarity, and the ones that failed review are published too. See the coverage reports and what was rejected.
The graph holds this control, the 2 it maps to, and the evidence behind each claim, over MCP and REST.