BS EN 61158-4-4:2014 - Page 2

Industrial communication networks. Fieldbus specifications. Data-link layer protocol specification. Type 4 elements | Status: Superseded, Withdrawn

1 Scope

1.1 General

The data-link layer provides 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