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DRS uses a 'Content Model' approach to provide the best preservation support for a limited set of file types. Any type of file, however, can be deposited into DRS using a specific Content Model, called an Opaque Object. Files in an Opaque Object are given bit level preservation, but there are limited delivery options. The DRS Content Guide explains which file formats are appropriate for each supported Content Model.
ETDs from ProQuest can have a variety of file types in each submission package. For a given ETD submission package, each file with a currently supported DRS Content Model will be deposited in a separate DRS Object and assigned a 'Role'. All files in a submission package with formats that are not currently supported by a DRS Content Model will be put into one Opaque ObjectObjects. The example in the table below illustrates how file types from a submission would be assigned to a Content Model.
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More rules for OSNs and filenames are in the BatchBuilder User Guide
Gathering information to create ETD Objects
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