The firewall must be configured to implement physically or logically separate subnetworks to isolate organization-defined critical system components and functions.

Separating critical system components and functions from other noncritical system components and functions through separate subnetworks may be necessary to reduce susceptibility to a catastrophic or debilitating breach or compromise that results in system failure. For example, physically separating the command and control function from the in-flight entertainment function through separate subnetworks in a commercial aircraft provides an increased level of assurance in the trustworthiness of critical system functions.

This requirement also applies to Zero Trust initiatives.

Verify the firewall is configured to implement physically or logically separate subnetworks to isolate organization-defined critical system components and functions.

If the firewall is not configured to implement physically or logically separate subnetworks to isolate organization-defined critical system components and functions, this is a finding.

Configure the firewall to implement physically or logically separate subnetworks to isolate organization-defined critical system components and functions.