The model provides different mechanism how Clients can transfer results provided by instances of the ResultManagementType. Not all implementations will provide all those possibilities.

The result consists of meta data describing the result, a relatively small amount of result data called ResultContent and optionally a larger amount of result data called ResultFile, transferred via the OPC UA file transfer. In some cases, the result only consists of parts of the meta data, the ResultEvaluation, which indicates whether the result is in a tolerance.

If a result has been successfully created, the Server shall at least provide the ResultContent, the ResultFile or the ResultEvaluation.

The ResultReadyEvents provide the meta data of the result as well as the ResultContent. Clients can either only subscribe to parts of the meta data and access the ResultContent via a different mechanism or get the ResultContent as well with the Event.

The ResultContent as well as the meta data can be transferred by calling the GetResultById Method. This requires knowledge on the ResultId, that can either be retrieved via the ResultReadyEvents or by calling the GetResultIdListFiltered Method. The latest ResultContent and its meta data can also be transferred by calling the GetLatestResult Method.

The ResultContent as well as the meta data is also provided by Variables under the Results folder and can be transferred by reading or subscribing to those Variables.

In Figure 3, the different options are displayed.

In case the result also contains a ResultFile, the ResultTransfer Object may be used to transfer the ResultFile. In order to use the ResultTransfer Object, the ResultId of the result is needed.

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Figure 3 – Transfer ResultContent and Metadata