ISO 22670:2013 defines the space link extension (SLE) return-channel-frames (RCF) service in accordance with the SLE Reference Model (ISO 15396:2007). The RCF service is an SLE transfer service that delivers to a mission user all telemetry frames from one master channel or one virtual channel.

ISO 22670:2013 defines the RCF service in terms of

1. the operations necessary to provide the service,
2. the parameter data associated with each operation,
3. the behaviors that result from the invocation of each operation, and
4. the relationship between, and the valid sequence of, the operations and resulting behaviors.

It does not specify

1. individual implementations or products,
2. the implementation of entities or interfaces within real systems,
3. the methods or technologies required to acquire telemetry frames from signals received from a spacecraft,
4. the methods or technologies required to provide a suitable environment for communications, or
5. the management activities required to schedule, configure, and control the RCF service.