System Interconnections | Restrictions On External System Connections, v1.0

Defines conformance and assessment criteria for verifying that an organization employs a defined access policy for allowing organization-defined information systems to connect to external information systems.
If an assessment step references organization-defined elements (E.g. <organization-defined personnel or roles>, <organization-defined frequency>, etc.), corresponding citations/excerpts must be provided to confirm that the organization has established and documented these values and that they apply as referenced in the conformance criteria.

Similarly, if a "Selection" among multiple options (e.g. [Selection (one or more): as needed; ]) is specified, evidence must be provided to establish that the option(s) implemented by the organization have been defined and documented.

The assessment step shall not be marked as satisfied without this evidence.

Assessment Step

1
System Interconnections | Restrictions On External System Connections (SystemInterconnectionsRestrictionsOnExternalSystemConnections)
Does the organization employ [Selection: allow-all, deny-by-exception; deny-all, permit-by-exception] policy for allowing [Assignment: organization-defined information systems] to connect to external information systems?
Artifact
A1
Provide evidence (e.g. organizational policies, procedures, compliance/assessment reports, etc.) that support the assessor's response to this assessment step.
Parameter
Access Policy Typerequired
ENUM_MULTI : Select the access policy types provided
  • allow-all
  • deny-by-exception; deny-all
  • permit-by-exception
If conformance criteria reference organization-defined elements (e.g. <organization-defined personnel or roles>, <organization-defined frequency>, etc.), these values must be defined and documented by the organization.

Similarly, if the criteria specify a "Selection" among multiple options (e.g. [Selection (one or more): as needed; ]), the option(s) implemented by the organization must also be defined and documented.

Conformance Criteria (1)

C1
The organization employs [Selection: allow-all, deny-by-exception; deny-all, permit-by-exception] policy for allowing [Assignment: organization-defined information systems] to connect to external information systems.
Citation
SP800-53R4
Appendix F, CA-3 (5)