Definition of DIP

From CLOCKSS Trusted Digital Repository Documents
Jump to: navigation, search

CLOCKSS: Definition of DIP

OAIS Dissemination Information Package (DIP)

The OIAS definition of DIP is:

Dissemination Information Package (DIP): An Information Package, derived from one or more AIPs, and sent by Archives to the Consumer in response to a request to the OAIS.

Other relevant definitions are:

Access Functional Entity: The OAIS functional entity that contains the services and functions which make the archival information holdings and related services visible to Consumers.
Access Rights Information: The information that identifies the access restrictions pertaining to the Content Information, including the legal framework, licensing terms, and access control. It contains the access and distribution conditions stated within the Submission Agreement, related to both preservation (by the OAIS) and final usage (by the Consumer). It also includes the specifications for the application of rights enforcement measures.
Access Aid: A software program or document that allows Consumers to locate, analyze, order or retrieve information from an OAIS.
Access Collection: A collection of AIPs that is defined by a Collection Description but for which there is no Packaging Information for the collection in Archival Storage.
Access Software: A type of software that presents part of or all of the information content of an Information Object in forms understandable to humans or systems.
Adhoc Order: A request that is generated by a Consumer for information the OAIS has indicated is currently available.
Collection Description: A type of Package Description that is specialized to provide information about an Archival Information Collection for use by Access Aids.
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.
Data Dissemination Session: A delivery of media or a single telecommunications session that provides Data to a Consumer. The Data Dissemination Session format/contents is based on a data model negotiated between the OAIS and the Consumer in the request agreement. This data model identifies the logical constructs used by the OAIS and how they are represented on each media delivery or in the telecommunication session.
Order Agreement: An agreement between the Archive and the Consumer in which the physical details of the delivery, such as media type and format of Data, are specified.
Ordering Aid: An application that assists the Consumer in discovering the cost of, and in ordering, AIPs of interest.

The OAIS discussion of DIP is:

In response to a request, the OAIS provides all or a part of an AIP to a Consumer in the form of a Dissemination Information Package (DIP). The DIP may also include collections of AIPs, and it may or may not have complete PDI. The Packaging Information will necessarily be present in some form so that the Consumer can clearly distinguish the information that was requested. Depending on the dissemination media and Consumer requirements, the Packaging Information may take various forms.

CLOCKSS Dissemination Information Package (DIP)

The CLOCKSS archive is a dark archive. The circumstances under which content may be disseminated from the archive are specified by the agreement that established it:

  • The publisher (i.e. the Producer) as owner of the copyright can request that it be disseminated to the publisher (not to a Consumer) in case of data loss at the publisher,
  • The publisher can request, or the CLOCKSS board can decide by following specified procedures, that it be disseminated to one or more institutions (not to a Consumer) willing to republish it under a Creative Commons license. Eventual Consumers access the content at the re-publishing institution(s), not from the archive, which remains dark.

Thus, if content is ever disseminated to a Consumer it will be via Web sites run by one or more institutions other than the CLOCKSS archive which have volunteered to do so.

Dissemination from the CLOCKSS archive is a one-time operation that does not involve "persons, or client systems, who interact with OAIS services to find preserved information of interest and to access that information in detail". In effect:

  • the Access Rights Information for eventual dissemination is the same for all content, and is specified by the agreements establishing the CLOCKSS archive,
  • the Access Functional Entity is not part of the archive,
  • nor is the Access Software;
  • there is no Data Dissemination Session based on an Order Agreement between the Archive and a Consumer; the agreement is between the archive and a re-publishing institution.

The purpose of creating a CLOCKSS DIP is therefore to transfer content from one or more AIPs either to its original publisher, or to an institution willing to republish it.

Creating DIPs from AIPs

As described in Definition of AIP the CLOCKSS archive contains two types of AIP:

  • A "harvest" AIP contains content ingested by crawling the publisher's web site.
  • A "file transfer" AIP contains content packaged and transferred to the archive by the publisher.

The processes which generate a DIP from AIPs of each type are different; both are described in CLOCKSS: Extracting Triggered Content.

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) accessed 2013.08.31
  2. CLOCKSS: Extracting Triggered Content