Publishers and Subscribers may be configurable through vendor-specific engineering tools or with the configuration Methods and parameters described in this standard. This allows a standard OPC UA Client based configuration tool to configure an OPC UA Server that is a Publisher and/or Subscriber.
Configuration parameters are exposed as Variables of the configurable Objects. Methods for creation of Objects have input arguments for mandatory Variables. Optional Variables are not contained in the input arguments of Methods for Object creation. Optional Variables are created with a default value if they are supported for the Object or required for the current configuration. The default value can be changed by writing to the Variable after creation. Newly created Objects shall have the Status Disabled_0 if they are created with the standard Methods.
Variables that can be configured shall have the CurrentWrite flag set in the AccessLevel Attribute. The UserAccessLevel may be limited based on the rights of the user of the OPC UA Client.
Configuration changes shall be applied in a batch to avoid inconsistencies between different configuration parameters. The mechanism to apply changes in a batch operation is to allow changes only when the related Object has the Status Disabled_0 and to apply the new configuration settings when the Status is changed to Operational_2. Therefore write operations to configuration parameters shall be rejected with Bad_InvalidState if the Status is not Disabled_0. Changes to PublishedDataSet configurations shall be rejected with Bad_InvalidState if not all related DataSetWriters have the Status Disabled_0.