redundancy (keeping multiple copies as a safeguard against loss). LOCKSS is significant in digital preservation terms because it established the feasibility of replication and peer-to-peer polling using standard personal computers.
OceanStore (oceanstore.cs.berkeley.edu)
The peer-to-peer concept demonstrated in LOCKSS is also the basis of OceanStore, whose web site describes it as a
global persistent data store designed to scale to billions of users. It provides a consistent, highly-available, and durable storage utility atop an infrastructure comprised of untrusted servers.
OceanStore’s features include data protection through redundancy and through its cryptographic techniques. Any computer can join the OceanStore infrastruc- ture, and users subscribing only to a single OceanStore service provider can access other OceanStore servers. Data is cached in OceanStore ‘promiscuously:
any server may create a local replica of any data object’. This offers benefits such as faster access. OceanStore claims that it can offer ‘durability which exceeds today’s best by orders of magnitude’ because digital material is stored on ‘hundreds or thousands of servers’ and so can be readily reconstructed. ‘Only a global-scale disaster’, they claim, ‘could disable enough machines to destroy the archived object’. Pond, a prototype of OceanStore, is being developed.
(This section is based on information available on the OceanStore web site (oceanstore.cs.berkeley.edu).)
In conjunction with the Charter on the Preservation of the Digital Heritage, UNESCO contracted the National Library of Australia to develop guidelines for digital preservation. These Guidelines for the Preservation of Digital Heritage (UNESCO, 2003) were made available via the UNESCO web site in 2003. They were the product of a wide international consultation process with all levels of interest groups, from governments to individual experts. The preface to the Guidelinesstates that their intention is to introduce ‘general and technical guide- lines for the preservation and continuing accessibility of the ever growing digital heritage of the world’ and that they are intended to complement the Charter on the Preservation of the Digital Heritage. They are best seen as ‘a guide to the ques- tions that programme managers need to find answers to’ and do not claim to address ‘every technical and practical question that will arise in managing digital preservation programmes’, relying rather on establishing and stating principles that can be applied (UNESCO, 2003, pp.7,11). The UNESCO Guidelines have already proved valuable to the digital preservation community for their compre- hensive approach and statement of principles, as the frequent reference to them throughout this book attests.
RLG (www.rlg.org)
RLG, founded as the Research Libraries Group in 1974, is a not-for-profit alliance of libraries, archives, museums, and historical societies with strong research collections. RLG was established to provide a mechanism for collaborative action on the problems facing research collections. Preservation has always been a major interest of RLG, demonstrated most recently by its significant digital preservation activities, particularly in advocacy and raising awareness and in standards development. RLG’s advocacy and awareness-raising activities include publication since 1997 of the electronic journal RLG DigiNews. Perhaps its most influential activity in digital preservation has been its participation, with the Commission on Preservation and Access, in the Task Force on Archiving of Digital Information. The report of this Task Force in 1996 (Task Force on Archiving of Digital Information, 1996) laid the foundations for much subse- quent work in digital preservation. RLG surveyed the digital preservation needs of its members in 1998 (Hedstrom and Montgomery, 1999).
RLG’s role in standards development is similarly significant. It participated in 1998 in the development of the OAIS Reference Model. It has participated in working groups, including:
• RLG-OCLC Working Group on Digital Archive Attributes, whose final report was Trusted Digital Repositories: Attributes and Responsibilities (RLG/OCLC Working Group on Digital Archive Attributes, 2002)
• OCLC-RLG Preservation Metadata Working Group, which produced A Metadata Framework to Support the Preservation of Digital Objects(OCLC/RLG Working Group on Preservation Metadata, 2002)
• Preservation Metadata: Implementation Strategies (PREMIS) Working Group, another joint RLG-OCLC working group, reported in 2004: Implementing Preservation Strategies for Digital Materials: Current Practice and Emerging Trends in the Cultural Heritage Community (OCLC/RLG PREMIS Working Group, 2004).
1111 2 3 4 51 6 7 8 9 10 1 2 3111 4 5 6 7 8 9 20111 1 211 3 4 5 6 71 8 9 30111 1 2 3 4 5 6 7 8 9 40111 1 2 3 44 45 46 47 48 49 50111
International initiatives and collaborations 167
Other RLG collaborations include a ‘fruitful working relationship and strategic partnership’ with JISC since 1999 (Dale, 2004, p.20). RLG staff have also been on the advisory groups of many collaborative digital preservation activities, such as CEDARS and CAMiLEON. RLG is a founding member of the DPC and has worked with the National Library of Australia on PADI. (This section is based on Dale (2004) and on the RLG web site (www.rlg.org).)
PADI (www.nla.gov.au/padi)
PADI (Preserving Access to Digital Information) describes itself as ‘a subject gateway to digital preservation resources’ and is considered by many as the essential starting point for digital preservation matters. It was established in 1997 by the National Library of Australia to share information about digital preservation and support activities in Australia and worldwide. PADI demon- strates the collaborative aspects that characterize many digital preservation activities: it is developed in cooperation with CLIR (the Council on Library and Information Resources) and the UK-based Digital Preservation Coalition, and has an international advisory group. PADI is described in more detail as Case Study 6 in the Appendix of this book.
OCLC (www.oclc.org)
The activities of OCLC in digital preservation sit uneasily with the distinction between services and alliances that is made in this chapter. OCLC has been active in both arenas. Some of its collaborative activities with RLG are referred to above.
OCLC was founded, as the Ohio College Library Center, in 1967, primarily to offer cataloguing services to US libraries. Now renamed Online Computer Library Center, it offers a very wide range of services, including digitization and preservation services, to an international clientele. In addition to the collab- orations with RLG already noted, OCLC’s digital preservation activities include a Registry of Digital Masters working group (again with RLG), and participa- tion on the board of METS (Metadata Encoding Transmission Standard), which may become an important industry standard for digital archives. It is also a partner in the DLF Format Registry working group, formed in January 2003 by OCLC, the DLF (Digital Library Federation), and international stakeholders such as JISC, NARA, the National Archives (UK) and JSTOR, which is investigating a registry of data formats to support digital preservation.
In addition to these collaborations, OCLC has maintained since 2003 a digital archive. This general purpose OAIS-compliant digital repository accepts mater- ials using OCLC’s web-archiving toolset or its batch ingest service. OCLC’s digital archive can handle multiple file formats. It links with Connexion (another OCLC service) and offers automatic metadata retrieval with its web harvester service. Its current bit-preservation techniques include circulating backups (onsite and offsite) and media migration, and it is developing processes that will probably combine migration and emulation. (This section is based on Bellinger et al.(2004) and OCLC’s web site (www.oclc.org).)
CAMiLEON (www.si.umich.edu/CAMILEON)
CAMiLEON (Creative Archiving at Michigan and Leeds), described in Chapter 7, is noted here because it is a significant example of an international digital
168 Digital Preservation Initiatives and Collaborations
preservation collaboration, in this case a research collaboration. From 1999 to 2003 the University of Michigan (in the US) and the University of Leeds (in the UK) combined forces to develop and evaluate a range of techniques for long- term preservation of digital materials. CAMiLEON’s reports and other publi- cations, available on its web site, remain valuable source material. Rushbridge considers its influence to have been in its high-profile activities, especially the BBC Domesday project (see Chapter 7), and its proof-of-concept of migration on request. CAMiLEON, he suggests, ‘has given leadership, attracted public attention, advanced both theory and practice, and highlighted many of the issues involved in digital preservation today’ (Rushbridge, 2004a, p.35).