International Journal on Digital Libraries

, Volume 9, Issue 2, pp 83–100 | Cite as

The aDORe federation architecture: digital repositories at scale

  • Herbert Van de SompelEmail author
  • Ryan Chute
  • Patrick Hochstenbach
Regular Paper


The need to federate repositories emerges in two distinctive scenarios. In one scenario, scalability-related problems in the operation of a repository reach a point beyond which continued service requires parallelization and hence federation of the repository infrastructure. In the other scenario, multiple distributed repositories manage collections of interest to certain communities or applications, and federation is an approach to present a unified perspective across these repositories. The high-level, 3-Tier aDORe federation architecture can be used as a guideline to federate repositories in both cases. This paper describes the architecture, consisting of core interfaces for federated repositories in Tier-1, two shared infrastructure components in Tier-2, and a single-point of access to the federation in Tier-3. The paper also illustrates two large-scale deployments of the aDORe federation architecture: the aDORe Archive repository (over 100,000,000 digital objects) at the Los Alamos National Laboratory and the Ghent University Image Repository federation (multiple terabytes of image files).


Interoperability Repository federation OAI-PMH OpenURL 


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Copyright information

© Los Alamos National Laboratory 2008

Authors and Affiliations

  • Herbert Van de Sompel
    • 1
    Email author
  • Ryan Chute
    • 1
  • Patrick Hochstenbach
    • 2
  1. 1.Digital Library Research and Prototyping TeamLos Alamos National LaboratoryLos AlamosUSA
  2. 2.Universiteitsbibliotheek, Universiteit GentGhentBelgium

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