Committed to building and maintaining collections for the use of students, faculty, scholars, and the public long into the future, the University of Illinois at Urbana-Champaign assumes an obligation to ensure long-term access to the materials deposited into IDEALS and their intellectual content, but also acknowledges the inherent challenges involved in preserving digital content.
To this end, the IDEALS Digital Preservation Support Policy defines the categories of preservation support available and provides specific information about where different file formats fit within these categories. This policy is subject to change as new and emerging technologies impact our ability to preserve deposited content.
Please note that IDEALS content is now being preserved in our Medusa repository, and is governed by the digital preservation support policies found there.
Our ability to preserve digital objects deposited in IDEALS is dependent, among other things, on whether the file format used:
All digital objects deposited to IDEALS will receive basic, "bit-level" preservation. Basic preservation means that IDEALS will preserve the viability of the original object through:
Basic preservation does not ensure that a digital object may be opened by a computer program or is understandable by a human in the future. For example, in 2006 a faculty member deposits a conference presentation in the Microsoft PowerPoint format (.ppt), a proprietary format. In 2030, a graduate student would like to view that conference presentation, but the software program - Microsoft PowerPoint - used to open and read .ppt files has been discontinued since 2020. Old versions of the software program are difficult to find, and, because the .ppt file format had never been publicly documented, there exist no other software programs to open the file. Even though the original digital object (the conference presentation in .ppt) is still technically viable, it is no longer renderable (able to be opened by a computer program), and thus not understandable by the graduate student in 2030.
Therefore, for digital objects that meet certain criteria (see below), IDEALS will strive to preserve not only the viability of the object but also the renderability and the understandability of the content of the digital object, as well as the original file itself. In the case of some objects in proprietary formats, this will mean that in addition to the original digital object, IDEALS will also save a copy of the object transformed into a file format that is more preservable than the original. For example, the conference presentation in .ppt might also be saved as a .pdf/a object (an open, publicly documented standard). The .pdf/a object is a more preservable format than the .ppt format. What may be lost is the full functionality of the original digital object. For example, the graduate student in our example may not be able to view the conference presentation as a slide show as the Microsoft PowerPoint software program allows. However, the content of the conference presentation will be preserved.
IDEALS also recognizes that in some cases an access copy of a digital object is necessary due to the proprietary nature or cost of the software used to render it. For example, a Microsoft Word document is reliant on the Microsoft Word program to render it; IDEALS will also provide a .pdf version of the document because .pdf readers are freely and readily available. In some cases, the access copy and the preservable copy may be the one and the same - a .pdf/a version, for example.
IDEALS categorizes digital objects into three categories of preservation support. These categories are defined below. Any format not yet reviewed and evaluated by IDEALS will receive Category 3 support on deposit. A different category may be assigned after format review takes place.
Most confidence in ability to provide long term preservation to content and functionality
Highest level of preservation support in effort to maintain viability, renderability, and understandability as well as functionality of original digital object.
Moderate confidence level in ability to provide long term preservation to content of file
Intermediate level of preservation support in effort to maintain maintain viability, renderability, and understandability (but not functionality) of original digital object.
OR
NOTE: Files with embedded content (for example, a PowerPoint (.ppt) with a AVI video file (.avi) inserted into it) are more preservable if the files are deposited as separate files within the same item in IDEALS. If the content remains embedded, it will likely not remain intact when the file is transformed to a more preservable format.
NOTE: Files with dynamic content (for example, an Excel spreadsheet (.xls) with dynamic functions - even simple ones!) are more preservable if the dynamic content is either documented (for example, a note in an Excel spreadsheet explaining the functions that are included) or the document is saved as a static document (for example, a cell in an Excel spreadsheet that is the sum of a column is saved as the sum, not the function of adding the multiple cells).
Low confidence level in ability to provide long term preservation to content of file
Basic level of preservation support in effort to maintain maintain viability of original digital object only.
| Preservation Action | Category 1 | Category 2 | Category 3 |
|---|---|---|---|
| Provision of persistent identifier for object and/or its metadata | X | X | X |
| Creation of preservation metadata | X | X | X |
| Secure storage and backup | X | X | X |
| Regular fixity checks | X | X | X |
| Regular virus checks | X | X | X |
| Periodic refreshment to new storage media | X | X | X |
| Storage of original digital object | X | X | X |
| Transformation to a more preservable format | N/A | X | |
| Strategic monitoring of format for changes | X | X | |
| Migration to successive format upon obsolescence | X |