OAIS

from Wikipedia, the free encyclopedia
OAIS reference model (1999)
Atari 1050 8 bit floppy disk drive

OAIS ( O pen A rchival I nformation S ystem or O ffenes A rchiv- I nformation S ystem) is a reference model for a dynamic, extensible archive information system in August 2012 as ISO standard 14721: published 2012th Version 2 expanded the original ISO standard from 2003. The OAIS reference model is the most important standard for electronic archiving .

history

OAIS was developed against the background of the insight that digitally archived documents could no longer be readable after a long time for various reasons. The development of the standard was initiated by NASA and promoted jointly with the space agency ESA and space research centers in Great Britain, Canada, France, Germany, Brazil, Japan and Russia. In May 1999 the Advisory Committee for Space Data Systems (CCSDS) presented the first draft "Reference Model for an Open Archive Information System (OAIS)", which was converted into ISO Standard 14721 in 2003. In 2009 a revised version followed, the CCSDS "pink book". This version 2 of OAIS was published in June 2012 by the CCSDS as "magenta book" (free download) and already adopted in August 2012 by the ISO as ISO 14721: 2012.

Problems to be considered with long-term archiving can arise. a. by

  • No longer available devices and applications to read and interpret archived media
  • User-specific or generally outdated, insufficiently documented formats
  • Loss of layout if the content was saved separately from the layout
  • Property rights

Reference model

The reference model describes an archive as an organization in which people and systems work together to make archive material available to a defined group of users. However, the implementation of an OAIS-compliant archive is not specified.

From the data point of view, OAIS assumes so-called information packages which, in addition to the content that is actually to be retained, also contain descriptive information (e.g. on the data format). The packages submitted by the producer for archiving ( SIP - submission information package ) are converted to archive information packages ( AIP - archival information package ) when they are transferred. These include a. also information on the history of previous edits or migrations in the archive as well as attributes that can guarantee integrity and authenticity. Research and access by end users are also carried out via special information packages ( DIP - dissemination information package ), which can be differentiated according to the request and the access rights.

Areas of responsibility

Functionally, OAIS defines six areas of responsibility, which are briefly described below.

Data transfer (ingest)

In addition to the physical transfer of the data in a container format (SIPs), further steps are required. The data must be checked for archival suitability, completeness and intactness. The Scanning for viruses is one of the most difficult challenges during ingest. Both the content and the technically descriptive metadata must be extracted. AIPs are generated from the information collected and stored in the repository (→ data storage). At the same time, → data management is informed about the new entry. Delivery standards such as XDOMEA , XBARCH, XISADG or eCH- 0160 and corresponding interfaces facilitate the data transfer from document management systems .

Archive storage

The archive storage ensures that the AIPs are physically preserved. Various IT security measures are used for this, such as redundant storage, backup and restore as well as regular data integrity checks. On request, the AIPs are read out and passed on to → access.

Data administration (management)

The data administration is responsible for the content and technical descriptive information of the AIPs. It can be used to identify archive holdings, it accepts research requests, processes them and organizes → access. The technical information is interesting and important for → maintenance planning.

Access

The access (use) area supports end users of the archive in researching the desired information. Here, inquiries are received, processed and the results converted into DIPs and made available to the end user according to his authorizations. Unlike in classic archives, the DIPs can be generated in various forms (representations) (e.g. as a screen preview and as a high-resolution print version).

Preservation Planning

Maintenance planning relates on the one hand to technological progress in the field of digital archiving and thus to the archive system itself. On the other hand, maintenance planning is used to develop and implement specific preservation methods. So z. B. the renewal of outdated AIP data formats can be organized, whereby issues of format conversion as well as the preservation of integrity and, if necessary, legally binding are important. Conceptually, this area is therefore of central importance.

OAIS is heavily oriented towards the migration method, but remains open to other approaches (e.g. emulation ).

System administration (administration)

The system administration concerns the archive as a whole system. Configuration settings are managed, the relationships between the components are organized and access rights are monitored.

Individual evidence

  1. ↑ "Open" here means that the development of the OAIS takes place in open forums, and does not refer to unrestricted access to an archive.

Web links