Supported Data Access Services

Data access by the BMENUA0100 module embedded OPC UA server stack is enabled by its support of the following facets and related services:

  • Data Access Server Facet

  • ComplexType 2017 Server Facet

  • Core 2017 Server Facet

NOTE: In the following facet descriptions, italicized text indicates a direct quote of the OPC Foundation source material. Click on the links below and use the OPC Foundation Unified Architecture Profile Reporting Visualization Tool to access a description of each facet.

Core 2017 Server Facet

The Core 2017 Server Facet defines the core functionality required for any UA Server implementation. The core functionality includes the ability to discover endpoints, establish secure communication channels, create Sessions, browse the AddressSpace and read and/or write to Attributes of Nodes. The key requirements are: support for a single Session, support for the Server and Server Capabilities Object, all mandatory Attributes for Nodes in the AddressSpace, and authentication with UserName and Password. For broad applicability, it is recommended that Servers support multiple transport and security Profiles. For a full description of this facet, refer to http://opcfoundation.org/UA-Profile/Server/Core2017Facet.

The BMENUA0100 module embedded OPC UA server stack supports the following conformance units in the Core 2017 Server Facet:

  • View Service Set, includes the following groups and services:

    • View Basic: includes the Browse and the BrowseNext services.

    • View TranslateBrowsePath: includes the TranslateBrowsePathsToNodeIds service.

    • View Register Nodes: includes the RegisterNodes and UnregisterNodes services as a way to optimize access to repeatedly used Nodes in the Server's OPC UA AddressSpace.

  • Attribute Service Set, includes the following groups and services:

    • Attribute read: includes the Read service, which supports reading one or more attributes of one or more Nodes, including support of the IndexRange parameter to read a single element or a range of elements when the Attribute value is an array.

    • Attribute Write values: includes the Write Value service, which supports writing one or more values to one or more Attributes of one or more Nodes.

    • Attribute Write Index: includes the Write Index service, which supports the IndexRange for writing to a single element or a range of elements when the Attribute value is an array and partial updates is allowed for this array.

Data Access Server Facet

The Data Access Server Facet specifies the support for an Information Model used to provide industrial automation data. This model defines standard structures for analog and discrete data items and their quality of service. This Facet extends the Core Server Facet which includes support of the basic AddressSpace behaviour. For a full description of this facet, refer to http://opcfoundation.org/UA-Profile/Server/DataAccess.

ComplexType 2017 Server Facet

The ComplexType 2017 Server Facet extends the Core Server Facet to include Variables with structured data, i.e. data that are composed of multiple elements such as a structure and where the individual elements are exposed as component variables. Support of this Facet requires the implementation of structured DataTypes and Variables that make use of these DataTypes. The Read, Write and Subscriptions service set shall support the encoding and decoding of these structured DataTypes. As an option the Server can also support alternate encodings, such as an XML encoding when the binary protocol is currently used and vice-versa. For a full description of this facet, refer to http://opcfoundation.org/UA-Profile/Server/ComplexTypes2017.