Agreement between DCMI and the FOAF Project


The Dublin Core™ Metadata Initiative (DCMI) is an open organization, incorporated in Singapore as a public, not-for-profit Company limited by Guarantee (registration number 200823602C), engaged in the development of interoperable metadata standards that support a broad range of purposes and business models. DCMI is the maintenance organization for the vocabulary DCMI Metadata Terms.

The Friend of a Friend (FOAF) Project aims at creating a Web of machine-readable pages describing people, the links between them, and the things they create and do, using an open, decentralized technology for connecting social Web sites and the people they describe. The FOAF Project is the maintenance organization for the FOAF Vocabulary.

Preamble on shared goals

The FOAF Vocabulary and DCMI Metadata Terms are often used together in applications, and both are consistently listed among the top vocabularies in the Linked Data space. As organizations, DCMI and the FOAF Project share a common interest in improving resource discovery across the boundaries of information silos on the Web. They share also share a common concern for balancing centralization and decentralization by encouraging the stabilization of third-party extensions and companion vocabularies that enhance the usefulness of the vocabularies they maintain.

This agreement outlines specific measures to be undertaken in cooperation between DCMI and the FOAF Project -- measures aimed primarily at reinforcing the long-term viability of the FOAF Vocabulary by addressing the risks inherent with having a single point of failure. The two organizations also see this cooperation as an opportunity for better integrating their vocabularies with alignments -- mutually declared mappings between semantically overlapping terms -- and for promoting the documentation of best-practice usage patterns in which the two vocabularies are used in combination.

Both organizations believe that arrangements of mutual support and cooperation among vocabulary maintainers such as this agreement can improve the long-term viability of RDF vocabularies in all niches of the Semantic Web ecosystem -- from vocabularies maintained by small, agile, time-limited projects or grass-roots initiatives to vocabularies maintained by stable cultural memory organizations -- and offer this agreement as a potential template for others.

Specific commitments

  • FOAF will arrange for its DNS (Domain Name Service) to be controlled by a Registrar account for FOAF as a project and will grant DCMI full technical and administrative access to the Domain Name (
  • The FOAF Project commits to pay Domain fees so that it is always at least one year, ideally two or more, paid in advance. DCMI commits to monitor this situation and to step in and take temporary or long term control and stewardship of the domain if the FOAF Project is no longer able or willing to maintain the vocabulary.
  • The FOAF Project affirms the maintenance and persistence principles outlined in a DCMI Generic Namespace Policy and commits to make no semantic changes in the FOAF vocabulary without advance public notice of at least two weeks.
  • This agreement is not a legally binding contract but the public expression of a collaborative partnership. Collaboration will be re-evaluated and re-affirmed annually. DCMI and the FOAF Project have chosen this mechanism rather than a binding and final transfer since it provides a more scalable template for other collaborative relationships. The agreement may, with no ill-will, be publicly ended by either party at any time.
  • The FOAF Project leads, Dan Brickley and Libby Miller, expect to manage all matters related to vocabulary maintenance in-house for the foreseeable future, including long-term planning for contingencies by which the project leads would become unable to manage the vocabularies themselves. DCMI's engagement with the FOAF Project serves both to promote active collaboration between the two vocabulary maintenance organizations and to underwrite the long-term viability of the FOAF vocabulary domain should the FOAF Project for any reason cease its normal activity. This collaboration also gives both projects a mechanism for sharing among themselves, and the wider community, details of their preservation-planning activities.
  • DCMI and FOAF will take measures to keep contact information reciprocally available and inform each other on plans and developments concerning their namespaces. Service outages of a few hours, even days, are a natural feature of the Web and are something for which implementers should plan. However, in the event that the FOAF namespace should become unavailable on the Web for an unusually extended period (e.g., more than two weeks), and communication with the FOAF Project leads cannot be established, DCMI agrees to step in and use its DNS access to arrange for temporary public hosting of the latest copy of FOAF namespace documentations. To prepare for this contingency, DCMI will download and periodically refresh a copy of the FOAF Subversion project.
  • For the longer term, if DCMI should find itself as the publisher of the final results of a FOAF Project that has ceased activity, DCMI will maintain the documentation of FOAF in conformance with the surrounding technical infrastructure (e.g., in response to a revision of W3C Resource Description Framework).