Preservation metadata: National Library of New Zealand experience.

ABSTRACT

Development of approaches to preservation metadata has been an integral component of international efforts in the field of digital preservation. The focus of the community engaged in this work is currently shifting, and there is, as yet, no formal agreement around a conceptual framework and identification of required data elements. At the same time attention is now turning to the more complex task of building sustainable technical, infrastructure, and policy frameworks that will enable organizations to implement preservation metadata strategies practically at a local level.

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The National Library of New Zealand, Te Puna Matauranga o Aotearoa, has been actively engaged in work on preservation metadata. This has involved development of a preservation metadata schema, a more granular implementation-ready data model/XML schema, a software application for programmatically extracting preservation metadata, and finally a repository for storing the gathered preservation metadata. This article contextualizes the National Library of New Zealand experience by discussing the purpose of preservation metadata and the ways that organizations may use this type of information in the future to support their long-term goal of preserving digital assets in perpetuity.

INTRODUCTION

It is not entirely clear where the phrase "preservation metadata" was coined. In their seminal 1996 report, Donald Waters and John Garrett noted that "metadata, which refers to information about information, is sometimes used as a generic term for systems of reference" and that "the preference for the term metadata ... appears to flow from the felt need to emphasize the special referential features needed in the digital environment and to distinguish those special features from those of more traditional systems of citation, description and classification" (Garrett & Waters, 1996, p. 47). A year later, in 1997, Lorcan Dempsey and Rachel Heery described a situation

 
   where a digital representation of the file exists, physical 
   characteristics of the representation (file size, format, 
   information documenting the capture process, etc.) will reside in 
   the header of the digital representation file, or if it is 
   maintained separately, in a separate metadata format and syntax 
   (e.g. a digital representation of a letter written by Mark Twain; 
   with separate physical characteristics and capture information 
   on each page-image). (Dempsey & Heery, 1997, p. 30) 

Also in 1997, Michael Day posed the question whether "as the archives community are seriously considering using metadata to ensure the integrity and longevity of records, it might be useful to investigate whether a similar approach would be useful for digital preservation in a library context--and in particular for networked documents" (Day, 1997). In 1998 the same author, under the auspices of the CEDARS project (Curl Exemplars in Digital Archives), began to answer that question by producing "a review of metadata formats and initiatives in the specific area of digital preservation," in which he notes "a growing awareness that metadata has an important role in digital resource management, including preservation" (Day, 1998). So within two years the notion of preservation metadata went from obscurity to center stage in the digital preservation work plan, where it has remained for the last six years or so.

This article describes the work undertaken by the National Library of New Zealand Te Puna Matauranga o Aotearoa (the Library) in this context of international developments in the preservation metadata arena. In addition, it both answers some questions regarding our ability to deal with an "uncontrollable and unmanageable flood" (University of Heidelberg, 2005) of digital materials through a series of pragmatic, staged steps (Thompson & Searle, 2003) and asks some questions about the development of an international approach regarding preservation metadata and why it has taken so long to arrive at a consensus.

ORGANIZATIONAL CONTEXT

In 2003 the Library's governing legislation was revised with the passing of the National Library of New Zealand (Te Puna Matauranga o Aotearoa) Act 2003 (New Zealand Government, 2003). The act defines the purpose of the Library as "to enrich the cultural and economic life of New Zealand and its interchanges with other nations by ... collecting, preserving, and protecting documents, particularly those relating to New Zealand, and making them accessible for all the people of New Zealand, in a manner consistent with their status as documentary heritage and taonga." (1)

The act also, for the first time, provides the Library with the mandate to engage fully with digital material, both online and offline, and to ensure that we accord digital material the same degree of responsibility and care we show our nondigital collections. Part 4 Section 29(1) defines an electronic document as "a public document in which information is stored or displayed by means of an electronic recording device, computer or other electronic medium, and includes an Internet document," which is further defined as "a public document that is published on the Internet, whether or not there is any restriction on access to the document; and includes the whole or part of a website" (New Zealand Government, 2003, p. 14). A public document is also defined elsewhere within the act.

It is within this context that the Library is undertaking a program of linked initiatives to ensure the incorporation of digital material into the Library's core business processes with a view to the long-term accessibility of those resources. The goal of the program is to develop holistic, end-to-end processes for the handling of digital material. The program includes the following activities:

* Developing and implementing business process work flows for incorporating digital objects into the Library's business processes; for example, selection, acquisition, care and handling, and transformation of digital originals

* Developing infrastructure for digital materials; for example storage, authentication, and access

* Researching and implementing "components" of the digital archive; for example, preservation metadata (schema, data model, extraction, storage) and persistent identifiers

* Implementing Web archiving for the capture and preservation of New Zealand-based and related Web sites

* Implementing a portal service for provision of access to all the Library's applications

The progress of the Library to date has thrown up a number of major areas of need that will require continued attention if the Library is to successfully confront the challenge of digital preservation. These include

* Recognition that while information in all formats is still increasing, more…