CLOCKSS: Designated Community

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CLOCKSS: Designated Community

OAIS Designated Community

The OAIS definition of Designated Community is:

Designated Community: An identified group of potential Consumers who should be able to understand a particular set of information. The Designated Community may be composed of multiple user communities. A Designated Community is defined by the Archive and this definition may change over time.

Other relevant definitions are:

Consumer: The role played by those persons, or client systems, who interact with OAIS services to find preserved information of interest and to access that information in detail. This can include other OAISes, as well as internal OAIS persons or systems.
Independently Understandable: A characteristic of information that is sufficiently complete to allow it to be interpreted, understood and used by the Designated Community without having to resort to special resources not widely available, including named individuals.
Knowledge Base: A set of information, incorporated by a person or system, that allows that person or system to understand received information.
Representation Information: The information that maps a Data Object into more meaningful concepts. An example of Representation Information for a bit sequence which is a FITS file might consist of the FITS standard which defines the format plus a dictionary which defines the meaning in the file of keywords which are not part of the standard. Another example is JPEG software which is used to render a JPEG file; rendering the JPEG file as bits is not very meaningful to humans but the software, which embodies an understanding of the JPEG standard, maps the bits into pixels which can then be rendered as an image for human viewing.

The OAIS discussion of Designated Community includes:

Consumer is the role played by those persons, or client systems, that interact with OAIS services to find and acquire preserved information of interest. A special class of Consumers is the Designated Community. The Designated Community is the set of Consumers who should be able to understand the preserved information.
The Designated Community, and its associated Knowledge Base, for whom the information is being preserved by the Archive is defined by that Archive, and that Knowledge Base will, as described below, change over time. The definition of Designated Community may be subject to agreement with funders and other stakeholders.
Since a key purpose of an OAIS is to preserve information for a Designated Community, the OAIS must understand the Knowledge Base of its Designated Community to understand the minimum Representation Information that must be maintained. The OAIS should then make a decision between maintaining the minimum Representation Information needed for its Designated Community, or maintaining a larger amount of Representation Information that may allow understanding by a larger Consumer community with a less specialized Knowledge Base, which would be the equivalent of extending the definition of the Designated Community. Over time, evolution of the Designated Community’s Knowledge Base may require updates to the Representation Information to ensure continued understanding. The choice, for an OAIS, to collect all the relevant Representation Information or to reference its existence in another trusted or partner OAIS Archive, is an implementation and organization decision.
The OIAS shall ... Ensure that the information to be preserved is Independently Understandable to the Designated Community. In particular, the Designated Community should be able to understand the information without needing special resources such as the assistance of the experts who produced the information. ... Make the preserved information available to the Designated Community and enable the information to be disseminated as copies of, or as traceable to, the original submitted Data Objects with evidence supporting its Authenticity.

CLOCKSS Designated Community

The CLOCKSS archive is a dark archive. No Consumers "interact with [CLOCKSS] services to find preserved information of interest and to access that information in detail". Content is not disseminated in response to requests from Consumers, but only as a consequence of the CLOCKSS Board declaring a trigger event. It is not disseminated to Consumers, but to re-publishing systems that are not themselves part of the Archive. The dissemination process is a transaction between the CLOCKSS archive and a re-publishing platform; it does not depend on a request from a Consumer nor does it deliver Content Information directly to a Consumer. If any Consumer ever accesses content that was preserved by the CLOCKSS archive, it will be from one of these re-publishing systems. The CLOCKSS archive will not be involved in this transaction, between the eventual Consumer and the re-publishing system, in any way. Nevertheless, it is useful to define the Designated Community of the CLOCKSS archive thus:

The readers of serials and books published via the Web, or one of its successor technologies.

This definition provides the following implications:

  • The Consumers in the Designated Community are the same set of people as the readers for whom the publisher originally published the Content Information.
  • Thus the goal of the CLOCKSS archive is simply that Content Information be rendered after being triggered as readably as it was when originally published; the semantics of the Content Information are not the responsibility of the archive.
  • The Knowledge Base of the Consumers in the Designated Community includes Web browsers, or their equivalent in a successor technology to the Web.
  • Thus in order for the Content Information to be Independently Understandable the CLOCKSS archive need only preserve the Representation Information supplied by the publisher with the Content Information to a Web browser:
    • At publishing time, the reader's browser had no other information on which to base its rendering, so it must have been adequate.
    • As a consequence of the fact that "there is no flag day on the Internet", if at triggering time Web browsers have been superseded by some other technology, then either:
      • That technology must be capable of directly rendering Web content using its Representation Information, or
      • Tools must be available to convert Web content and its associated Representation Information into a format which the new technology can render.
  • Thus, when constructing a Dissemination Information Package to transfer triggered content to a re-publishing system, there are two possibilities:
    • The current equivalent of the Web browser can render previous Web content directly, in which case no transformation of the Content Information or the Representation Information is needed, or
    • The Content and Representation Information can be transformed using available tools into a format which the current equivalent of the Web browser can render (see LOCKSS: Format Migration).

Interested Parties

It is evident that, because it is a dark archive, the relationship between the CLOCKSS archive and the Consumers in its Designated Community is too remote to support the functions OAIS expects it to perform. The CLOCKSS archive defines a community of Interested Parties in three parts:

  • The scholars, students and readers of electronic academic content.
  • The libraries who purchase and manage this content on behalf of the scholars, students and readers.
  • The publishers of this content.

The archive is governed by a board composed of twelve libraries, with the advice of the general library membership, on behalf of the community of scholars, students and readers, and twelve publishers, with the advice of the general publisher membership.

The CLOCKSS Archive delivers services to each of its Interested Parties by providing a sustainable, geographically distributed dark archive that ensures the long-term survival of Web-based, scholarly publications:

  • Scholars, students and readers are provided with free, open access under Creative Commons Licenses to content that would otherwise have become inaccessible.
  • Librarians are reassured that the content which they purchase will remain accessible to their readers.
  • Publishers are relieved of the responsibility of providing for access to their content in the event that they are no longer able or willing do so.

Change Process

Changes to this document require:

  • Review by LOCKSS Engineering staff
  • Approval by LOCKSS Chief Scientist

Relevant Documents

  1. OAIS (2012) CCSDS 650.0-M-2: Reference Model for an Open Archival Information System (OAIS). Magenta Book. Issue 1. June 2012 (ISO 14721:2003) http://public.ccsds.org/publications/archive/650x0m2.pdf accessed 2013.08.31
  2. LOCKSS: Format Migration