Increasing experience in developing and maintaining large repositories of digital objects suggests that changes in the large- scale infrastructure of archives, their capabilities, and their communities of use, will themselves necessitate the ability to manage, manipulate, move, and migrate content at very large scales.
Migration at scale of digital assets, whether those assets are deposited with the archive, or are created as preservation system artifacts by the archive, and whether migration is employed as a strategy for managing the risk of format obsolescence, for repository management, or for other reasons, is a challenge facing many large-scale digital archives and repositories.
This paper explores the experience of Portico (www.portico.org), a not-for-profit digital preservation service providing a permanent archive of electronic journals, books, and other scholarly content, as it undertook a migration of the XML files that document the descriptive, technical, events, and structural metadata for approximately 15 million e-journal articles in its archive. It describes the purpose, planning, technical challenges, and quality assurance demands associated with digital object migration at very large scales.
iPRES, iSchool, Toronto, Canada, digital preservation, archives management, format migration, transformation, at scale, normalization