EN 61158-6:2004

This part of EN 61158 is one of a series produced to facilitate the interconnection of automation system components. It is related to other standards in the set as defined by the three-layer Fieldbus Reference Model, which is based in part on the Basic Reference Model for Open Systems Interconnection. Both Reference Models subdivide the area of standardisation for interconnection into a series of layers of specification, each of manageable size. This standard describes the Fieldbus Application Layer (FAL) protocol that defines the information interchange and the interactions between Application Entity invocations (AE-Is) to support the Application Services. The Application Protocol provides the Application Service by making use of the services available from the Data Link Layer or other immediately lower layer.