IEC 61158-3-19:2014 defines the services provided to the Type 19 fieldbus application layer at the boundary between the application and data-link layers of the fieldbus reference model and systems management at the boundary between the data-link layer and systems management of the fieldbus reference model. This third edition cancels and replaces the second edition published in 2010. It constitutes a technical revision. The main changes are: - introducing connections based on a producer-consumer model; - introducing additional mechanisms to realize features such as timestamping and oversampling; - improving the hotplug and redundancy features; - improving the phase switching and the error handling; - editorial improvements.