AC-20 - Use of External Systems

a. [Selection (one or more): Establish [Assignment: organization-defined terms and conditions] ; Identify [Assignment: organization-defined controls asserted to be implemented on external systems] ], consistent with the trust relationships established with other organizations owning, operating, and/or maintaining external systems, allowing authorized individuals to: 1. Access the system from external systems; and 2. Process, store, or transmit organization-controlled information using external systems; or b. Prohibit the use of [Assignment: organizationally-defined types of external systems].


ID: AC-20
Enhancements:  1 | 2 | 3 | 4 | 5

Space Segment Guidance

External interconnections may include partner ground stations, relay services, or science processing environments. Consider strict separation of TT&C from other networks; documented, minimal interfaces with defined protocols and formats; and interconnection agreements that reflect pass scheduling, key management, audit exchange, and incident coordination. Testing these boundaries in a twin/flatsat environment can surface assumptions before flight.