The Attributes of Nodes, their DataTypes and descriptions are defined in OPC 10000-3. Attributes not marked as optional are mandatory and shall be provided by a Server. The following tables define if the Attribute value is defined by this specification or if it is server-specific.
For all Nodes specified in this specification, the Attributes named in Table 4 shall be set as specified in the table.
Table 4 − Common Node Attributes
|
Attribute |
Value |
|
DisplayName |
The DisplayName is a 0:LocalizedText. Each server shall provide the DisplayName identical to the BrowseName of the Node for the LocaleId “en”. Whether the server provides translated names for other LocaleIds is server-specific. |
|
Description |
Optionally a server-specific description is provided. |
|
NodeClass |
Shall reflect the NodeClass of the Node. |
|
NodeId |
The NodeId is described by BrowseNames as defined in 4.4.2.1. |
|
WriteMask |
Optionally the WriteMask Attribute can be provided. If the WriteMask Attribute is provided, it shall set all non-server-specific Attributes to not writeable. For example, the Description Attribute may be set to writeable since a Server may provide a server-specific description for the Node. The NodeId shall not be writeable, because it is defined for each Node in this specification. |
|
UserWriteMask |
Optionally the UserWriteMask Attribute can be provided. The same rules as for the WriteMask Attribute apply. |
|
RolePermissions |
Optionally server-specific role permissions can be provided. |
|
UserRolePermissions |
Optionally the role permissions of the current Session can be provided. The value is server-specific and depend on the RolePermissions Attribute (if provided) and the current Session. |
|
AccessRestrictions |
Optionally server-specific access restrictions can be provided. |