2.1 Why is the National Archives introducing these standards?
Most digital file formats become obsolete over time because they rely on software and hardware to view and use the record. This means that many digital records will become inaccessible without intervention.
Technologies change rapidly and format obsolescence can happen quickly. However, planning and managing the risk of format obsolescence helps ensure that records remain accessible. It also preserves their authenticity and integrity for future use and reuse, in line with the Australian Government’s Public Data Policy. Agencies play a critical role in realising this policy.
The National Archives’ Building trust in the public record policy recommends that agencies create digital information assets in sustainable digital formats (action 13). It also recommends agencies implement strategies, including storage and preservation strategies, for the management of all information assets (action 12), and plan ways of addressing gaps in their interoperability maturity (action 11).
2.2 Why did the National Archives choose these formats?
We chose the formats listed in these standards because they have a low risk of becoming obsolete.
According to the Australasian Digital Recordkeeping Initiative (ADRI), a file format has a low risk of becoming obsolete if meets the following criteria:
- Widely adopted: The format is widely used and supported around the world.
- Unrestricted: The format is free from patents and legal encumbrance. It preferably uses open-source principles.
- Well documented: The format is identifiable and the specification is publicly available. The specification is detailed enough that people with the right skills can create software to display it correctly.
- Stable: The file format is stable and new versions are only released rarely. The format is backwards and forwards compatible or has a clear migration path.
- Platform independent: The format is supported by a wide range of software or is platform-independent.
- Uncompressed: The format is uncompressed or uses lossless compression.
- Supported: Technical support is readily available from vendors, the community or third parties.
- Metadata friendly: The file format supports metadata.
Not all file formats used for preservation meet all of these criteria. However, they have a combination of these characteristics while still remaining fit for purpose for business use. In general, the more of these criteria a format satisfies, the lower the risk of obsolescence.
These standards are based on international best practice. They contain many formats commonly used by Australian Government agencies and they will be regularly reviewed and updated to include additional file formats that are suitable for preservation.
3. Want to know more?
Please contact the Agency Service Centre if you would like more information on these file format standards or advice on implementing them in your organisation.