Digital Preservation Policy

Preserving Archival Digital Records Transferred from Commonwealth Agencies

July 2009

1,2, July 2011

1. Policy statement

The National Archives of Australia (the Archives) undertakes to ensure the long-term preservation and accessibility of the archival resources of the Commonwealth which were created or managed in a digital format.

2. What is digital preservation?

Digital preservation is the process of active management by which the National Archives ensures that a digital object will be accessible in the future.

3. Objectives of digital preservation at the National Archives

The National Archives aims to preserve any type of digital record that is:

  • created using any type of application;
  • created on any computing platform;
  • delivered on any digital media;
  • from any Commonwealth agency or approved Personal Records depositor (Personal Records are the records of current and former prime ministers, ministers and others involved with the Commonwealth government); and
  • provide discovery and access for current and future generations.

4. Challenges to the preservation of digital records

The preservation of digital records represents a significant challenge for both government agencies and archival institutions. Factors affecting the level of risk include:

  • The carriers used to store digital records are usually unstable and deteriorate within a few years or decades at most.
  • The use of digital records requires specific combinations of hardware and software that typically become obsolete after a few years, rendering the digital records inaccessible.
  • File formats change over time, which can mean that the digital records are inaccessible using current software.
  • File formats are sometimes unable to be determined, especially for older software.
  • Digital records may be lost in the event of disasters such as fire, flood, equipment failure, or virus or direct attack that disables stored data and operating systems.
  • Access barriers such as password protection, encryption and security devices may prevent ongoing access beyond the circumstances for which they were designed.
  • The digital records may be well protected, but so poorly identified and described that potential users cannot find them.
  • So much contextual information may be lost that the records themselves are unintelligible or not trusted.

The inherent instability and vulnerability of digital records affects the ways in which the Archives secures, manages and preserves digital records.

5. Scope

Under the Archives Act 1983 the National Archives is responsible for preserving Commonwealth records that form the archival resources of the Commonwealth. These include born-digital records and digital preservation master copies of analog originals.

The Archives only accepts records from government agencies that have been sentenced Retain as National Archives (that is, for permanent retention) under a records authority. ('Sentencing' is a process of using a records authority or other instrument to decide whether to retain, destroy or transfer a record. Records authorities are issued to individual agencies by the National Archives and cover agency-specific core business.) In exceptional circumstances the Archives will accept records whose value has not been identified, for example records that are at risk or are considered a significant resource.

The Archives does not preserve the means used to create, manage or present digital records, for example records management software. The Archives accepts exports of digital records and their metadata from systems, not exports of the systems themselves.

6. Digital preservation principles

The Archives' digital preservation capability:

  • addresses the root causes of digital obsolescence by deploying software tools to ensure that proprietary file formats are accessible in the long-term, and reducing the frequency and complexity of digital preservation treatments;
  • adheres to existing community-based, open standards in developing the technical and organisational capability for digital preservation;
  • ensures long-term independence from information technology vendors and providers;
  • ensures interoperability and the opportunity for cooperation and collaboration by employing open source software solutions;
  • develops processes and procedures to ensure the authenticity, integrity and security of digital records; and
  • develops processes and procedures to ensure that archival requirements of provenance and original order are met.

7. Digital preservation approach

The Archives converts digital records to fully-specified, standards-based open formats (that is, formats whose specification is fully and openly published). The conversion occurs when the records are ingested into the Digital Archive. This is a 'migration' approach to digital preservation that limits the number of preservation treatments applied to each digital record, thereby minimising the risk of altering or damaging the record.

This approach is referred to as ‘normalisation’ because the Archives converts digital records to a small number of open ‘preservation’ formats. The Archives also retains a copy of the original digital record to return to if a chosen preservation format is superseded, or if a better approach is developed. In this way the Archives ensures sustainability and flexibility.

8. Preservation formats

The Archives uses preservation formats selected through a rigorous research and testing regime. The Archives assesses potential preservation formats against the following criteria:

  1. The full specification of the format must be openly available.
    As the specification of an open format is publicly available, anyone with sufficient skills and incentive can build software to read it accurately. It also means that it is easier to understand the underlying file format, which is important for long-term preservation.
  2. No patent, intellectual property rights or other rights attach to the format.
    Some file formats have been patented by their creators. That means that it is only possible to create software to read or write it if you license the format from the patent holder. This creates a problem for the long-term preservation of, and access to, the digital record.

9. Records which cannot be converted to an open format

In some cases, documents are unable to be converted into an open format. Reasons for this include:

  • The file format specification for the existing document is not available.
  • Software is not available to read the document.
  • Suitable conversion software for certain types of document does not exist.
  • A suitable open format for that type of document does not exist.

The Archives stores these documents in their existing format and reprocesses them when the appropriate ‘normaliser’ is available.

10. Essential characteristics of digital records

The Archives cannot guarantee that the conversion process results in an absolutely identical document. For example, not all of the fonts in an original word processing document may be available on the system used to view the normalised version.

However, the Archives endeavours to capture those characteristics of the original record that are essential to preserve its meaning. For example, for documents the Archives will preserve the content and enough of the appearance, structure and context of the original record to convey the originator's intentions. By preserving the essential characteristics of digital records, the Archives ensures that records retain their value as evidence.

The Archives uses the best conversion technology available at the time of conversion. It also has the capability to convert either the original or normalised versions again if better conversion methods are developed.

11. Cooperation / collaboration

The Archives is committed to collaborating with other Commonwealth agencies, archival institutions with an interest in digital preservation, and other stakeholders to advance the development of digital preservation tools and processes, share lessons learned and develop expertise in digital preservation domestically and internationally.

Copyright National Archives of Australia 2018