Topic 3 - Introduction to the OAIS Reference Model

Open Archival Information System

ISO 147214:2012

Desired and designed by NASA

The Graph

Mandatory responsibilities

  • Negotiate & accept appropriate information.
  • Obtain sufficient control over the information.
  • Determine scope of community needs.
  • Ensure the preserved info is understandable independently without assistance.
  • Safeguard your items (contingencies, deletions, …)
  • Make it available.

The 3 Areas of Operation

  1. External environment
    producer, consumer, and management

  2. Functional components
    of the repository itself

  3. Information packages
    being preserved and disseminated

Locate the 3 Areas

External environments, Functional components, Information packages

Information Objects

“[are] either a physical or digital Data Object with Representation Information that ‘allows for the full interpretation of data into meaningful information’” — ImpactZone

Information Object Packages

SIP, AIP, DIP

  • SIP:
    Submission Information Package

  • AIP:
    Archival Information Package

  • DIP:
    Dissemination Information Package

Find the Information Packages

Information Objects

“[are] either a physical or digital Data Object with Representation Information that ‘allows for the full interpretation of data into meaningful information’” — ImpactZone

Representation Information

Examples? Ideas?

Representation Information

Example: ASCII Table

Representation Information

…for images, audio, video?

Representation Information

So, what could you store alongside your files?

It’s a recursion.

Digital Representation Information is an Information Object that may have its own Data Object and its own Representation Information associated with understanding each Data Object.

…meaning:

  • To preserve the meaning of an Information Object, its Representation Information must also be preserved.

  • This recursion continues until physical forms, which can be understood by the Designated Community, are encountered.
Are we there yet?

Information Types

  • Semantic
  • Structure
  • Other

Information Types

  • Semantic
    Example: Text, but which language?

  • Structure
    Example: File format definition
    (header, payload, …)

  • Other
    None of the above ;)
    Example: Which software required

Common misunderstandings

  • You don’t have to implement OAIS,
    but it’s a good reference.
  • There’s no “common format” for SIPs, AIPs, DIPs. but there are good/best practices
  • It doesn’t have to involve XML
    …or a specific metadata standard.
    (but it also doesn’t hurt ;P)
  • Perfect can be the enemy of good
    (Aim for a sweet spot!)
  • Don’t assume “it’s clear to everyone” WHO your designated users are.

Comments?

Questions?

OAIS Background

  • The Consultative Committee for Space Data Systems (CCSDS) initiated work aimed at developing formal standards for the long-term storage of digital data generated from space missions.

  • The OAIS reference model was approved in January 2002 as ISO International Standard 14721;

  • a revised and updated version was published in 2012 as ISO Standard 14721:2012.

  • Design and revisions have taken place concurrent and in partnership with the growth of the profession into one that has boundaries, curricula, and standards of practice.

OAIS Background

  • For a type of archive consisting of an organization of people and systems that has accepted the responsibility to preserve information for one or more designated communities.

  • A reference model = an abstract framework or domain-specific ontology consisting of an interlinked set of clearly defined concepts produced by an expert or body of experts in order to encourage clear communication.

  • Strictly a conceptual framework.

  • Sets the standard for the activities that are involved in preserving a digital archive rather than the method for carrying out those activities