Digital preservation aims at planning, allocating resources and applying the necessary methods and technologies to ensure that digital information remains accessible and usable in perpetuity. However, the long-term preservation of digital information requires trust in the reliability and the ability of the institution to provide the content of the documents consistently unaltered. Ensuring that the information provided has remained unchanged over time is a particular challenge, given the numerous factors that can cause a digital object to be modified. The aim of the paper is to use methods from the field of cryptography for the preservation of digital documents. Specifically, blockchain technology is proposed for the trusted timestamping of documents in a way that cannot be disputed, and moreover without the need for a trusted party to guarantee the accuracy of the data. At the same time, a processed version of the document is stored in such a way that, on the one hand, it can be identified with absolute certainty and, on the other, it is impossible to extract the original information. In this way, possession of a digital document can be proven beyond any doubt without revealing its content. All this constitutes irreplaceable tools for the protection of intellectual property and makes it possible to create a value-added service for the institutions that implement them. Creators of digital content are given an additional incentive to entrust their creations to music libraries and archives, since the copyright in their work will be protected as a matter of course. Finally, the implementation of the method at the Laboratory for the Study of Hellenic Music of the Department of Music Studies of the National and Kapodistrian University of Athens is presented.
Presentation. The paper was presented at the 3rd Conference of Greek Music Libraries of the Greek Branch of the International Association of Music Libraries, Archives and Documentation Centres (IAML), in Thessaloniki, on Saturday 11 May 2019, in Session B (“N. Germanos” conference centre, Thessaloniki International Fair). The text was published in the proceedings of the 2nd, 3rd and 4th Conferences of Music Libraries, Archives and Documentation Centres (Athens 2025).