Standard Object Types

The BaseObjectType is the base type and all other object types shall either directly or indirectly inherit from it.

Typically, the components of an ObjectType are fixed and can be extended by subtyping. However, since each Object of an ObjectType can be extended with additional components, the OPC Unified Architecture specification allows extending the standard object types with additional components. Thereby, it is possible to express the additional information in the type definition that would already be contained in each Object. Some object types already provide entry points for server specific extensions. However, it is not allowed to restrict the components of the standard object types defined in the specyfication. An example of extending the ObjectType is putting the standard property NodeVersion defined in section Standard Node Classes into the BaseObjectType, stating that each Object of the server will provide a NodeVersion.

In This Section

There are defined tree groups of types derived from the BaseObjectType. They are dedicated to support management and information organisation of the:

Types supporting management of the Address Space - providing general information about organization, modelling and coding - are described in the topic Address Space Management. This group includes the following types derived from the BaseObjectType:

ModellingRuleType: This ObjectType is used as the type for the modelling rules.
FolderType: Instances of this ObjectType are used to organise the Address Space into a hierarchy of nodes.
DataTypeEncodingType: This ObjectType is used as type for the data type encodings.
DataTypeSystemType: This ObjectType is used as type for the data type systems.

Objects of types supporting management and organisation of the server related information provide runtime diagnostic and capabilities information are described in the topic Server Management. This group includes the following types derived from the BaseObjectType:

ServerType: This ObjectType defines the capabilities, diagnostic and redundancy supported by the OPC Unified Architecture server.
ServerCapabilitiesType: This ObjectType defines the capabilities supported by the OPC Unified Architecture server.
ServerDiagnosticsType: This ObjectType defines diagnostic information about the OPC Unified Architecture server.
SessionsDiagnosticsSummaryType: This ObjectType defines diagnostic information about the sessions of the OPC Unified Architecture server.
SessionDiagnosticsObjectType: This ObjectType defines diagnostic information about a session of the OPC Unified Architecture server.
VendorServerInfoType: This ObjectType defines a placeholder Object for vendor-specific information about the OPC Unified Architecture server.
ServerRedundancyType: This ObjectType defines the redundancy capabilities supported by the OPC Unified Architecture server.

All types supporting management of events are derived from BaseEventType - this is base event type. These types are described in the topic: Events Management.

Related Sections

BaseObjectType

This ObjectType is the base type and all other object types shall either directly or indirectly inherit from it.

Address Space Management

This topic describes types supporting management of the Address Space and providing general information about organization, modelling and coding.

Server Management

This topic describes types represented by the ObjectType node used to create objects exposed by the server Address Space providing runtime diagnostic and capabilities information.

Events Management

This section defines standard event types, i.e. types of the nodes providing events. They are represented in the Address Space as ObjectType nodes.