Deep Blue Documents Preservation

Overview

Deep Blue Documents follows the U-M Library’s Digital Preservation Policy to ensure the long-term accessibility and usability of deposited materials. File formats are classified into three levels based on their preservation support, as outlined in the U-M Library Registered Formats and Support Levels Document. For more information on ensuring your documents are accessible, see Creating Accessible Works.

Preservation Services

For all content you deposit, Deep Blue Documents will provide secure storage, backup, management, fixity checks, and periodic refreshment by copying Works to new storage media. We will also undertake appropriate format monitoring and provide adequate staffing and other resources to support the services offered. Further, Deep Blue Documents provides a permanent, unique Digital Object Identifier (DOI) for all Works.

Different Levels of Format Support

You may deposit a Work in any digital format in Deep Blue Documents, but not all formats can receive the same level of preservation commitment. Deep Blue Documents has designated three levels of support we can offer, based on criteria such as the wide deployment of the format, availability of publicly-documented specifications, and the expectation that tools will be available to undertake controlled transformation or migration. They are described in detail in the U-M Library Registered Formats and Support Levels Document.

Below are examples of common file formats for each of the levels of support offered:

  • Level 1
    • Example file format: TIFF (.tiff, .tif)
      • Why is this file format Level 1? It’s widely used and an open standard.
    • Example file format: PDF/A (“A" stands for archive)
      • Why is this file format Level 1? This file format has been developed as an international preservation standard, ISO 19005-1 for PDF/A-1.
  • Level 2
    • Example file format: Microsoft Word Document (.doc, .docx)
      • Why is this file format Level 2? Microsoft owns and controls the specifications for this format, but doesn't publish them. Some features like macros may not operate between versions, regardless of our best preservation efforts.
    • Example file format: PDF
      • Why is this file format Level 2? Adobe Systems, Inc. owns and controls the specifications for this format, but doesn't publish them.
  • Level 3
    • Example file format: Windows Media Audio (.wma)
      • Why is this file format Level 3? Microsoft owns and controls the specifications for this format, but doesn't publish them. It’s also far less common than other audio formats (such as MP3 and WAV). We can only commit to preserving Level 3 file formats at the bit level. In other words, in the future you will be able to download an exact copy of the deposited file, but it may be difficult to open and use it without legacy hardware and/or software.

For a list of all recognized Deep Blue Documents formats and their current support levels, see Creating Accessible Works. We expect to add to and revise the support levels as standards emerge for digital preservation of additional formats.

Preserving Relationships in Works with Multiple Files

At present, the three levels of preservation commitment are made at the individual file level. We will need to evaluate complex content -- Works composed of files in various formats that interact with each other -- to determine whether the operational relationships between the files can be maintained.

For example, when preserving a website in Deep Blue Documents, you must consolidate all web pages into a single directory and update any internal links to reflect this new, flattened structure. This includes renaming files and adjusting link references to ensure the website functions properly as a self-contained entity.

Executables and some files that rely on a specific hardware/software environment will also require additional evaluation because not only the format but the access environment must be considered in determining preservation issues. Please Contact Us if you wish to deposit any of these content types.

Digitizing Print Documents for Deposit

Deep Blue Documents focuses on new digital materials.

That said, we encourage Collection Administrators and individuals (including Library selectors and departmental liaisons) to continue to identify historical materials, both in digital and non-digital form. Members of the U-M community have produced a tremendous amount of interesting Works, and that will require prioritization, especially when each Work must be digitized to make it available through Deep Blue Documents. Please Contact Us if you have Works of this nature and we will work with you to make them available.

The Deep Blue Documents staff, in collaboration with the Library’s Digital Conversion Unit, may be able to help you digitize print documents and deposit them into Deep Blue Documents, making them accessible in a digital format. The Library doesn’t have the capacity to digitize microfilm.

FFor smaller batches of print documents (fewer than 100 items or 12 linear feet), the turnaround time is typically 6–8 weeks. Larger batches may be sent to a vendor and could take 6–9 months for scanning and quality review. Processing times may vary depending on batch size and current capacity.

If you're interested or have any questions about the process, please Contact Us.