A joint research project in the United Kingdom is investigating the use of blockchain technology to ensure the accuracy of historical documents.

Project ARCHANGEL, a research initiative funded by the National Archives in the United Kingdom and based out of the University of Surrey, is testing blockchain solutions that preserve the long-term integrity of documents saved within digital archives for public institutions.

The ARCHANGEL project is creating a prototype using blockchain technology which aims to enable archives to generate and register hashes of documents (similar to unique digital signatures) into a permissioned blockchain (in other words, one which can only be added to by authorised organisations).

Where the record has been legitimately changed, hashes of the content, alongside hashes of the code used to make the change, can also be registered on the blockchain. This would mean that whenever a digital record is modified, an audit trail is created and users are able to know exactly how a document has been edited.

Alex Green, Digital Preservation Services Manager, writes on The National Archives blog, “Our approach will result in the creation of many copies of a persistent and unchangeable record of the state of a document. This record will be verifiable using the same cryptographic algorithms, many years into the future.

“As this approach matures, we hope that the ledger would be maintained collaboratively by distributing it across many participating archives both in the UK and internationally, as a promise that no individual institution could attempt to rewrite history. This technology could transform the sustainability of digital public archives, enabling archives to share the stewardship of the records and, by sharing, guarantee the integrity of the records they hold.”

ARCHANGEL has a proposed timeframe of 18 months. It is set to prototype a distributed ledger technology (DLT) service that will "collect robust digital signatures derived from digitized physical, and born-digital content," according to Green.

The research is funded by the Engineering and Physical Sciences Research Council, which invests more than £800 million a year in fields such as mathematics, materials science, and information technology.