Workbook on Digital Private Papers > Digital preservation strategies > Selecting the right preservation strategy
Selecting the right preservation strategy
There are various theories on the best way to preserve digital material, and a number of different approaches have been developed, which in turn have variants. They range from preserving the original technology on which the archival digital objects ran, to preserving only the significant properties of an object, which are defined independently of any specific hardware or software platform. Each approach has advantages and disadvantages.
Thibodeau suggests that a digital archive should take the following four criteria into consideration when selecting a preservation strategy:
- Feasibility: possession of hardware and software capable of implementing the chosen method.
- Sustainability: the method should be capable of being applied indefinitely into the future; or there should be another path which will offer a sequel to the method if it ceases being sustainable.
- Practicality: implementation should be within reasonable limits of difficulty and expense.
- Appropriateness: the chosen approach should be appropriate for the particular types of digital objects to be preserved and the objectives of their preservation.
In particular he emphasises appropriateness and applicability as important factors in deciding on an approach:
- Decisions about appropriateness should be based on an informed evaluation of the significant properties of the object(s) to be preserved.
- Some preservation methods only apply to specific hardware or software platforms, some to individual data types or formats, while others are very general. Depending on the range and variety of digital objects to be preserved by a repository, selection of approach might be limited to methods that are optimal for this range, or (if very wide ranging) a method with broad applicability should be chosen.
The two principal competing strategies are migration and emulation. These two approaches and some of their variants are considered here.
