3. Preserve

This workflow describes the process of transferring content to secure storage and preserving it. If there are terms that you are unfamiliar with on this page, please refer to the glossary for the most common terms used in digital preservation.

3.1 Storage

This is an essential step

  • The NDSA Levels of Digital Preservation are useful for planning storage – in particular the sections on ‘storage’ and ‘control’. Think about creating several copies, in different physical locations and using different storage technologies.
  • If you currently have no storage, think about some practical solutions. For example, as an interim approach you could use your organisation’s storage network (see the guidance below for more information).
  • Think carefully about who in your organisation is allowed to access the digital content and the type of access that they have (e.g. read, write, move, delete). Keep a record of who has access.

Further guidance

3.2 Move to storage

This is an essential step

  • Before moving the content to the storage, check that the documentation you created in step 1 and step 2 has been saved in the ‘metadata’ folder.
  • If you use a collection management system, you may wish to add some of this documentation to it (e.g. the accession record or catalogue) or record where it is stored.
  • Some archives will package the content and metadata in a ‘bag’ using software such as Bagger.
  • Move the content to the storage. You could use copying software (see below) to do this to ensure date information and other file attributes are preserved.
  • Some software will also check the copied content to ensure it is identical. If not, use checksum software to check this (see step 1.4).
  • If applicable, you may decide to keep the original storage media or photograph it.

Software

Further guidance

3.3 Check checksums and access

This is an essential step

  • Use checksum software (see below) to carry out regular integrity checks of the content.
  • Keep a record of when you carry these out.
  • If checksums of content do change then investigate. For example, if the content is corrupt or has been accidentally changed, it may need to be replaced.
  • Ideally, you should keep logs of actions performed on content and carry out periodic reviews of these logs.

Software

Further guidance

3.4 Monitor storage

This is an essential step

  • The lifetime of storage can be short – it can fail or corrupt the content.
  • You will need to review your storage every 3-5 years and move content onto new storage.
  • Create multiple copies and use a mix of different types of storage technologies if you can.
  • For hard drives there is software that can help you with this (see below).

Software

Further guidance

3.5 Monitor content

  • You should monitor your content to understand if any of the file formats you hold, or the software/technology needed to access them, are at risk of becoming obsolete (outdated or no longer used).
  • One solution is format migration where a file format is converted into a new file format. However if you do this it is important to also keep the original content.
  • Some archives undertake format migration during step 2 (Ingest) and convert particular types of content into a preferred file format (called normalisation). Others wait until the risk of the content becoming obsolete is high.
  • One low-cost option is to only migrate the content when someone wants to access it.
  • Several types of software can carry out format migration and some are listed below.
  • Emulation is an alternative to format migration and attempts to recreate the functionality of the original software or technology.

Software

Further guidance

For the next stage of the digital preservation workflow, head over to the Access page.