scope:

This Recommendation I International Standard defines in an abstract way the externally visible service provided by the OS1 Transport Layer in terms of: a) the primitive actions and events of the service; b) the parameter data associated with each primitive action and event; c) the relationship between, and the valid sequences of, these actions and events. The service defined in this Recommendation I International Standard is that which is provided by all OS1 Transport Protocols (in conjunction with the Network Service) and which may be used by any OS1 Session Protocol.