2.1.1.3 Identifiers, handles, and blobs

   OPC data accesses use both server and client side handles created based on identification texts for nodes and items. To make the translation from identification texts to handles fast and avoid repeated translation in OPC an intermediate server side identifier called the blob exists. In DAIS the server side handles and blobs are replaced by identifiers based on ResourceIDs (both for nodes and items). For a description of ResourceIDs refer to Section 2.2, “Data Access Facility (DAF),? on page 2-4. The OPC client side handles are still kept in DAIS.