As more law libraries are developing independent digital
collections it is important to take into consideration the preservation of those
documents for the future. One main component of this is to ensure that the
files and corresponding metadata have not been corrupted. While many of us are fortunate
enough to have a third-party system hosting our content that we can rely on to
maintain the integrity of our documents, this isn’t something that is
universally true.
If you aren’t relying on a third-party system, and in many
cases even if you are, you will want to maintain independent copies of your
data. A good guideline to follow is the NDSA’s
Levels
of Digital Preservation. This tiered set of recommendations provides
solutions for institutions of all sizes and allows you to start small and build
up. Bear in mind that the goal is to develop these guidelines over time, so it’s
a good idea to check back occasionally to see if they have been updated.
One of the central concepts of these guidelines is the idea
of fixity, or stability, of digital documents. In essence fixity is information
that can be used to confirm that unauthorized changes have not been made to digital
content. NDSA has recently released a draft version of a Fact Sheet,
Checking
Your Digital Content: How, What and When to Check Fixity?, that helps
identify the reasons behind identifying and then checking fixity, as well as
several ways to go about doing so and where to store fixity data once it has been obtained.