This document specifies a part of the application, the application layer, and the presentation layer.

The application covers the

— device model,

— registry management,

— connection management for streaming data,

— diagnosis, and

— error handling.

The application layer covers the structure of MOST messages consisting of

— addressing,

— function block identifiers,

— instance identifiers,

— function identifiers,

— operation types, and

— timing definitions.

The presentation layer covers the definition of data, basic data types and function classes.