Historical
IEC 61158-4-4 Ed. 1.0 en:2007
Industrial communication networks - Fieldbus specifications - Part 4-4: Data-link layer protocol specification - Type 4 elements
"It basic time-critical messaging communications between devices in an automation environment. This protocol provides a means of connecting devices through a partial mesh network, such that most failures of an interconnection between two devices can be circumvented. In common practice the devices are interconnected in a non-redundant hierarchical manner reflecting application needs. It includes the following significant changes with respect to the previous edition deletion of the former Type 6 fieldbus, and the placeholder for a Type 5 fieldbus data-link layer, for lack of market relevance; addition of new types of fieldbuses; division of this part into multiple parts numbered."
CONTENT PROVIDER
International Electrotechnical Commission [iec]
International Electrotechnical Commission [iec]