ISO 21459:2015 defines synchronization and channel coding schemes for Proximity-1 links in terms of:

a) the services provided to the users of this specification;

b) data formats; and

c) the procedures performed to generate and process the data formats.

It does not specify:

a) individual implementations or products;

b) the methods or technologies required to perform the procedures; or

c) the management activities required to configure and control the protocol.

The Coding and Synchronization Sublayer is part of the Data Link Layer. The rest of the Data Link Layer is defined in the separate CCSDS Recommended Standard entitled, Proximity-1 Space Link Protocol-Data Link Layer (reference [3]). The Physical Layer is defined in the separate CCSDS Recommended Standard entitled, Proximity-1 Space Link Protocol-Physical Layer (reference [4]).