Risk analysis for accessions of digital objects

Our goal is to maintain the availability of the digital objects we collect for a long time to come. The use of digital objects can be affected by various risk factors. Sources of risk include certain attributes of the digital objects themselves as well as the systems with which we process and use them. We have derived a set of test criteria from the known risk factors that help us assess the long-term availability of the files received.

Since the end of 2012, we have been checking all objects received according to several technical criteria. First we check whether the digital object is complete and free from defects. We use checksums to guarantee and perform regular checks of completeness. When storing a digital object in the long term, it must be possible to access it at any time; for this reason, we do not accept encrypted data.

All data is checked automatically by means of a test procedure encompassing several steps. The more criteria are fulfilled, the higher the ingest level of the digital object. The higher the ingest level, the higher the probability that the digital object can be preserved for long-term use.

The ingest level established is recorded in a file format policy for every registered supplier after the first delivery. This check is applied to all digital objects, also to works digitized during the course of collection preservation measures, for example. As soon as an object falls below the fixed ingest level, it is rejected and not taken into storage.

Risk management facilitates the implementation of measures to prepare digital objects for long-term storage and preserve them in the event of damage.

Which quality criteria do we apply?

The format policy uses examples to explain the quality criteria and recognised file formats.

File format and ingest level policy