ConfigurationData describes a collection of Variables within a FunctionalEntity that are used to set up and configure its functionality. As part of establishing a Connection between FunctionalEntities, some configuration might be required. This configuration is separate from the configuration required for the actual communication. The EstablishConnections Method allows any of the FunctionalEntity’s ConfigurationData to be set.

ConfigurationData can contain Variables that have the AccessLevelEx Attribute NonVolatile bit set to TRUE(see OPC 10000-3). After a power cycle, such Variables are initialised to the last value written before the power cycle.

OPC UA FX defines the concept of the storage of Variables (see 6.4.6). Variables that do not have the AccessLevelEx Attribute NonVolatile bit set can be configured to be part of the storage and are initialised to the stored value following a power cycle.

Variables that are not stored and do not have the AccessLevelEx Attribute NonVolatile bit set have an unspecified value (e.g., vendor-specific value) after a power cycle.

It is up to the provider of the FunctionalEntity whether to provide NonVolatile ConfigurationData or to support storage of Variables.