ISO 18445:2013 specifies extensions to the API needed for support of the Command Link Transmission Unit (CLTU) service defined in CCSDS 912.1-B-2.
ISO 18445:2013 defines extensions to the SLE API in terms of:
- the CLTU-specific functionality provided by API components;
- the CLTU-specific interfaces provided by API components; and
- the externally visible behavior associated with the CLTU interfaces exported by the components.
It does not specify
- individual implementations or products;
- the internal design of the components; and
- the technology used for communications.
ISO 18445:2013 defines only interfaces and behavior that must be provided by implementations supporting the forward CLTU service in addition to the specification in CCSDS 914.0-M-1.