Royal Danish Library’s Policy for Digital Preservation

Find out more about our policy for the preservation of the library's collections of digital cultural heritage material.

The policy describes the general framework for the library's work with the preservation of our collections of digital cultural heritage material.

Contents

Introduction

The following constitutes the policy for the preservation of digital collections at Royal Danish Library. The policy outlines the framework and principles for the digital preservation work involving those parts of the cultural heritage for which Royal Danish Library is responsible.

Relationship to other policies

This policy is a single element in a complex of policies, strategies and guidelines concerned with digital material. The complex embraces all active policies concerning collections, including policies for acquisition, access, digitisation, and preservation of analogue material. Furthermore, the policy is linked to active strategies in the aforementioned areas.

What is covered by this policy

The policy covers all of Royal Danish Library's digital collections of cultural heritage, that is the policy includes both statutory and non-statutory collections of cultural heritage, as well as born-digital and digitised cultural heritage collections. Generally speaking, all the library’s digital cultural heritage collections are preserved.

The options for carrying out digital preservation are defined by conditions that apply based on external factors such as legislation, finance, international technological, methodological and organisational development within the field and the nature of the digital material. These conditions are described in the policy.

The policy also describes the principles adopted for the performance of activities in connection with digital preservation, which Royal Danish Library will endeavour to follow within the existing framework.

In order to ensure implementation of the policy, the overall organisation of the work involving digital preservation in the form of roles and responsibilities is defined in the policy.

Purpose and vision

Under the conditions that apply at the time in question (described in the section entitled ‘Framework for implementation of the policy‘), Royal Danish Library’s policy for digital preservation shall ensure the best possible conditions for long-term preservation of that part of the digital cultural heritage for which the library is responsible.

The policy thus lays down the framework on a general level, as well as the library’s principles for working with digital preservation. It is developed in order to ensure that digital preservation is carried out the best way possible both in the short term and the long term.

This means

  • that the library’s digital collections maintain their authenticity over time
  • that preserved data can be accessed in accordance with applicable legislation and agreements reached
  • that the preserved data can be interpreted in a contemporary manner

Digital preservation is a field in which

  • international collaboration is necessary in order to solve the resource-demanding and challenging tasks
  • surveillance and adaptation is necessary as change is a constant factor in terms of technology, methodology and organisation, both nationally and internationally
  • a sustained high level of competence is required

Royal Danish Library’s vision is thus to

  • prioritise the necessary organisation and financing to solve the task
  • follow and contribute to developing international standards and best practice
  • collaborate with other national and international organisations to the extent that this can help to achieve the best possible digital preservation
  • be one of the instigators of digital preservation in Denmark and contribute to the development of systems and infrastructure to support digital preservation 
  • promote knowledge of digital preservation and its importance at all levels
  • live up to the principles of a "Trustworthy Digital Repository" (see reference)

Background

One of the responsibilities of Royal Danish Library is the long-term preservation of digital material. Seen in relation to preservation institutions’ traditional preservation of analogue material, the long-term preservation of digital material constitutes an area with its own challenges. Some of the key challenges particular to digital material are that

  • the quantity of digital material is growing
  • the complexity of digital material is growing (formats, structures, et cetera)
  • digital material cannot be set aside in a passive manner until needed, as is the case for books, for example, since systems, storage media, data formats and programs are in a constant state of change. A failure to act – also during the early phases – will therefore result in a loss of ability to provide access to the preserved data
  • complete methods and solutions to these issues do not exist, but work is being carried out internationally to develop strategies and techniques that can handle some of the problems for subgroups of the material
  • there are no ready-to-use models in terms of the cost of activities, neither annually nor in terms of the total cost during the lifetime of the material, but work is being carried out internationally on establishing such cost models
  • legislation concerning storage and access to these types of material is more restrictive than for analogue material.

The nature of the material means that it is necessary to begin preservation activities during the acquisition process and subsequently on an ongoing basis in order to ensure access to the preserved digital material over time.

Ongoing long-term preservation consists of two main activities: bit preservation and functional preservation. In order for Royal Danish Library to be able to perform these preservation tasks, the institution must be in a position to continuously handle changes in the conditions for preservation, whilst also ensuring preservation within the applicable current framework conditions.

Framework for implementation of the policy

This chapter describes the framework conditions that are significant in terms of the policy and thereby the performance of activities in connection with digital preservation. Royal Danish Library must be able to continuously handle changes in the conditions for preservation, whilst also ensuring preservation within the current framework conditions. If the framework conditions change, the strategy must therefore be adjusted with respect to the new conditions and in relation to risk management and applicable principles.

Legislation and agreements

The preservation activities for Royal Danish Library's digital material follow relevant legislation, guidelines and concluded agreements concerning acquisition, administration (including preservation) and access. This applies to the legislation relating to among other things legal deposit, copyrights, data protection and archives. The library responds on an ongoing basis to relevant legislation and guidelines in the area.

Financing

Preservation activities for the library’s digital material are subject to the economic framework and budgets that are in effect at any time.

Royal Danish Library assesses on an ongoing basis whether the necessary resources to cover the costs of digital preservation are available.

Technological, methodological and organisational development

There is ongoing developments in technological, methodological and organisational areas on which digital preservation and solutions for digital preservation depend. Royal Danish Library follows and responds to this development in among other things the following areas:

  • Technology that is used in processes concerning preservation activities (for example in characterisation, validation, planning, formats)
  • Methods for digital preservation (for example preservation strategies, auditing methods)
  • Standards (for example Open Archival Information System, standards for formats, including metadata and compression)
  • International collaboration at an overall level (for example for web harvesting, format catalogues, registration and collecting of operating system software)
  • Collaboration on bit preservation (for example infrastructure in collaboration with foreign national libraries or Danish institutions, national preservation initiatives with other Danish institutions)
  • Research (for example unravelling new initiatives within digital preservation)

Digital materials

Digital materials vary in size and complexity, and both characteristics can affect the possibilities for digital preservation.

Size

Size can be expressed in several ways:

  • Number of files
  • Size of the files
  • The overall need for storage

Complexity

Complexity can be expressed in several ways:

  • Data formats
  • Composition of digital material
  • Context of digital material

Size and complexity may have an impact on digital preservation both technologically and financially.

Organisation

Royal Danish Library ensures performance of this policy by establishing an organisation, which supports the task. The organisation covers roles and responsibilities as described in the chapter 'Responsibility for implementation of the policy' and relevant processes described in the chapter 'Administration of the policy'.

Principles for implementation of the policy

This chapter describes the adopted principles, which are sought to be maintained within the framework conditions described in the previous chapter 'Framework for implementation of the policy'.

Risk management

Preservation activities for digital material at Royal Danish Library are based on principles for risk management with particular focus on risks related to the loss of data and future accessibility.

Trustworthy Digital Repository

Royal Danish Library ensures trustworthy digital preservation to the greatest possible extent. The overall principles for a "Trustworthy Digital Repository" (see reference) are thus followed.

This means, among other things, that the library regularly audits the organisation and technology that constitute the library’s digital archives. Royal Danish Library has no plans to secure formal certification.

Standards

Royal Danish Library keeps abreast of and, if possible, participates in the international collaboration that takes place concerning the development of standards and models for description and construction of the technical and organisational solutions related to the administration and preservation of digital collections. The library uses such standards to the greatest possible extent in the solution and evaluation of preservation-related tasks.

At an overall level, the library uses the OAIS model (ISO 14721) (see reference) as its reference model. The library also uses the principles contained in the OAIS-based auditing and certification standard ISO 16363 (see reference).

Data, metadata and data formats

Royal Danish Library seeks to preserve its digital collections in formats suitable for digital preservation. This will as far as possible involve formats, which are open, standardised and internationally acknowledged – and this applies to both data and metadata.

When choosing data formats, it will be taken into account whether the given formats are expected to be able to support one or more of the preservation strategies that the library chooses to use (for example emulation or migration).

Metadata is designed according to locally described norms that are as close as possible to international standards and best practice.

The decision concerning the use of techniques that can constitute a risk of loss of data, such as encryption or compression, must be based on a risk assessment and involve consultation with the management.

Metadata and its relation to data must be preserved.

The library uses universal, unique and persistent identifiers for identification of preserved digital materials.

Open and proprietary software

Any choice of software for use in digital preservation must be based on a risk assessment. This applies to both proprietary and open software.

In order to ensure openness and reciprocal exchange of experience, Royal Danish Library endeavours to support and practise the use of Free and Open Source Software (FOSS).

Ingest principles

Royal Danish Library endeavours to define requirements to ingested material to the greatest possible extent. This involves, for example, requirements concerning formats and structures for digitised material and born-digital material. In addition relevant policies are followed, cf. section ‘Relationship to other policies’.

All ingested material is assigned a universal, unique and persistent identifier, which can be used for future reference of the material.

Materials in Netarkivet are handled differently, however, as these can be identified universally, uniquely and persistently by specification of the web archive and properties on harvesting which make them uniquely identifiable (as, for example, via a Persistent Web IDentifier (PWID).

Preservation principles

For each digital collection that Royal Danish Library acquires for preservation, a decision has to be made as to what is to be preserved in terms of content, structure, functionality and appearance. For each collection, a decision also has to be made with regard to preservation level, including bit security, the desired functional preservation strategy and encryption, if applicable.

The library aims to do bit preservation of data and metadata in the form it had at the time of acquisition, also when further processing takes place.

Digital preservation must be sufficiently independent of the supporting system portfolio so that it is possible to restore data and metadata under conditions in which (parts of) the system portfolio has been lost.

Internationally recognised standards are used that ensure administration, retrieval and preservation of the digital collections.

Furthermore, an ongoing technological monitoring of relevant tools, formats and standards, et cetera, takes place.

Bit preservation

Royal Danish Library will use risk management for continuous assurance of bit preservation, which for long-term preservation consists of avoiding risks that may lead to data loss. At Royal Danish Library, risk handling is carried out for example by copies of the data being stored in independent environments (geographically, technically and organisationally) and by checking copies actively (unlike backup).

Bit preservation must be carried out as technology and vendor independent as possible to minimise risks related to for example a change in supplier.

The library strives to ensure that bit preservation takes place at different levels so that different demands concerning information security (confidentiality, integrity and accessibility) can be satisfied to the greatest possible extent.

In certain cases, the library’s preservation strategy can – in addition to one or more digital copies that are bit preserved – also include an analogue copy. In these cases risk assessment will include both the analogue and digital copies.

Royal Danish Library aims to collaborate with other organisations in order to achieve the best conditions for bit preservation.

As a general rule, material under bit preservation must not be deleted. Deletion may only be carried out on the basis of a risk assessment and following consultation with the management.

Functional preservation

Continuous monitoring of the composition and volume of the preserved collections is carried out and plans are formulated for the preservation of each collection.

In collaboration with national and international partners, Royal Danish Library will work to develop methods for functional preservation that ensure that as large a part of the library’s collections as possible will be accessible in the future.

If, due to technical or economic reasons, it is not possible to preserve all functionality in digital material in connection with a preservation activity being carried out, the preservation of the digital object’s intellectual content is usually awarded the highest priority.

The library uses risk management for continuous assurance of functional preservation.

Access to preserved digital materials

Royal Danish Library will make preserved collections accessible using a technology and in a format that is chosen on the basis of criteria involving economic considerations and relevance for the users. Access is only granted to digital collections under active preservation.

Technical infrastructure

Royal Danish Library establishes and maintains the necessary technical infrastructure in order to be able to carry out the preservation of its digital collections, in which:

  • the infrastructure supports the necessary monitoring of systems, media and formats in order to ensure a proactive effort
  • the infrastructure supports the necessary preservation activities such as bit preservation, characterisation, validation, migration and emulation
  • the infrastructure includes tools to help support decision-making processes and to monitor the performance of specific preservation activities
  • endeavours are made to standardise the infrastructure for different materials where possible in order to support overview, transparency and operational reliability.

Continuous risk management of the infrastructure is carried out with a view to its support of digital preservation. As a minimum, this includes known deficiencies, known challenges and consequences of changes in the infrastructure or framework for the infrastructure.

The library aims to keep the technical infrastructure for digital preservation as cost-effective as possible within the framework described in this policy, although with particular focus on risk management.

In the actual structuring of digital materials that undergo long-term preservation, the library uses universal, unique and persistent identifiers.

Research, knowledge-sharing and competence development

Royal Danish Library ensures that its personnel always have adequate professional knowledge such that the preservation policy can be maintained and implemented responsibly, irrespective of whether this is carried out in-house or outsourced.

The library aims to ensure that this competence development and maintenance takes place through internal training of personnel and via participation in national and international conferences, collaboration and partnerships with among other things libraries, archives and universities. The library takes part in relevant external research projects in the field, as well as instigating research projects itself.

The library disseminates the knowledge that is acquired on digital preservation to the public domain via relevant channels, for example websites, projects and conferences.

Collaboration on preservation activities

Through strategic collaboration projects or open source projects, Royal Danish Library endeavours to secure a key position in international networks that work with digital preservation, such that legally, politically and in terms of knowledge, methods and tools the library is on a par with comparable institutions in Europe.

Where appropriate, the library contributes to partnerships and joint maintenance operations with Danish or international preservation institutions that possess the necessary expertise.

Responsibility for implementation of the policy

In order to be able to meet the challenges concerning digital preservation, Royal Danish Library, through its organisation and division of responsibilities, must ensure that

  • maintenance of the library’s policy for digital preservation is in accordance with the library’s objectives and responsibilities for digital cultural heritage
  • maintenance of the library’s strategy for digital preservation is in accordance with the current risk status, applicable framework conditions for digital preservation and Royal Danish Library's Digital Preservation Policy
  • implementation of the library’s strategy for digital preservation is in practice

The overall responsibility for digital preservation lies with Royal Danish Library’s management, which

  • prioritises resources for digital preservation at an overall level
  • appoints those responsible for the roles that are related to digital preservation
  • approves the policy and appoints those responsible for approval of strategy and risk status, as well as consequent priorities for digital preservation.

Administration of the policy

This policy is the second version of Royal Danish Library's Digital Preservation Policy, updated in the spring of 2024.

Updating of the policy

Updating of the policy is ensured by the department responsible for digital preservation and is approved by Royal Danish Library’s management every five years or more frequently if this is required due to changes in conditions for digital preservation.

Dissemination of the policy

The policy is published via the library’s website in a Danish and an English version with the aim of supporting national and international collaboration on digital preservation.

Reference list

Internal documents related to the Digital Preservation Policy

The following internal documents and draft documents related to the Digital Preservation Policy are used in the process of drafting the policy:

  1. Royal Danish Library (2019): Accession policy
  2. Royal Danish Library (2024): Royal Danish Library's strategy for digital preservation
  3. Royal Danish Library (2019): Strategy for the digitisation of physical cultural heritage
  4. Royal Danish Library (2021): Strategy for the accession of digital cultural heritage
  5. Royal Danish Library (2019): Policy for access to the digital collections
  6. Royal Danish Library (2020): Strategy for access to the digital collections

External documents related to the Digital Preservation Policy

The following external documents have a direct impact on this Digital Preservation Policy:

  1. ISO 14721:2012 (2012): Space data and information transfer systems - Open archival information system (OAIS) - Reference model
  2. ISO 16363:2012 (2012): Space data and information transfer systems - Audit and certification of trustworthy digital repositories
  3. Eld Zierau: URN Namespace Registration for Persistent Web IDentifiers (PWID)
  4. ISO 27001:2022 (2022): Information security, cybersecurity and privacy protection

Previous policies

This Digital Preservation Policy replaces Royal Danish Library's Digital Preservation Policy from January 2019.