. OPC Unified Architecture Part 8: Data Access. Release 1.05.00. 2021-10-12. , OPC Foundation, 2021.

This document is part of the OPC Unified Architecture (OPC UA) standards series and defines the information model related to Data Access (DA). It provides a detailed explanation of the representation of automation data on servers, new structured variable types (such as AnalogItem, BaseAnalogType, DiscreteItem, ArrayItem, etc.), the Address Space model, and engineering units, as well as the mapping and bridging mechanisms between legacy OPC COM DA systems and OPC UA.