This Recommendation | International Standard defines in an abstract way the externally visible service provided by the OS1 Session Layer in terms of
- the primitive actions and events of the service;
- the parameter data associated with each primitive action and event;
- the relationship between, and the valid sequence of these actions and events.
The service defined in this Recommendation | International Standard is that which is provided by the OS1 session protocol (in conjunction with the transport service) and which may be used by the OS1 presentation protocol.