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ISO 14721:2003 - OAIS. A Reference Model for an Open Archival Information System. NASA Involvement / CCSDS, ISO Status.
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ISO 14721:2003 - OAIS A Reference Model for an Open Archival Information System Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
NASA Involvement / CCSDS, ISO Status • OAIS was developed under Consultative Committee for Space Data Systems (CCSDS)/ISO Technical Committee (TC) 20: Aircraft and Space Vehicles, and its Sub-Committee (SC) 13: Space Data and Information Transfer Systems • Promote standards for “archiving” space information. • NOT restricted to space - reference model is general in application • Focus is digital information • CCSDS 650.0-B-1, January 2002 • ISO 14721:2003, March 2003 Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
What is an ‘Open Archival Information System Reference Model’ • Open • Reference model is open, not necessarily system or information in system • Archival • Preserve information long enough to be concerned with the impacts of technology, make it available to a designated community. • Information System • Hardware, software, people and functions. • Reference Model • Abstraction for understanding significant entities and relationships. • Not a “reference architecture”. Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Information Archive Special Concerns • The archived information must be useable by consumers who are separated in time, distance and background from the producers. • OBSOLECENCE in years, not decades • Media, hardware and software • PRESERVATION of information MEANS keeping up with CHANGES • USE and USER determine acceptable packaging • Same information, different forms Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Benefits of OAIS Reference Model • Vocabulary: • A common framework for discussion & description • Completeness: • Comprehensive description of the functional parts and roles of a digital archive [at a REFERENCE MODEL level of detail]. • Does not restrict implementation: • Map OAIS functions and roles onto YOUR archive design, if you’ve got OAIS covered, you can be confident that your design is addressing the archive issues. Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Significance of OAIS • Provides a vocabulary for discussing issues around what a digital archive is. • Producers, consumers and management can understand each other. • Is complete - if you’ve covered the topics in the document you can be confident that you’re system has the necessary characteristics. Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Figure 2-1: Environment Model of an OAIS (page 2-2) OAIS (archive) Producer Consumer Management Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Environment Model of an OAIS: Roles • Producer • Clients (persons or systems) who provide the information to be preserved • Management • Maintainers of the system, set overall policy, etc • Consumer • Clients (persons or systems) who interact with OAIS services to find and acquire preserved information of interest Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Figure 2-3: Information Package Concepts and Relationships (page 2-5) {S,A,D} I P Content Information Preservation Description Information Packaging Information Description Information about Package 1 Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Information = Data + Representation • Challenge to OAIS, what is the information to be preserved? • Preservation Description Information (PDI) requires that the true nature of the content is known • Preservation may mean changing the bits AND the associated representation information to keep pace with technology change. Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Preservation Description Information • Provenance Information • Source, custody, processing algorithm, history • Context Information • Relates Content Information to information outside the Information Package (Documentation, citations, related information) • Reference Information • Provides identifiers for Content (URLs, handles, service IDs) • Fixity Information • Protects from undocumented alteration, authenticity (checksums) Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Figure 2-4: OAIS Archive External Data (page 2-8) Producer SIP OAIS AIP Result sets queries orders Consumer DIP Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Three Incarnations of an Information Package • Submission Information Package • Negotiated between Producer and OAIS • Sent to OAIS by a Producer • Archival Information Package • Information Package used for preservation • Includes complete set of Preservation Description Information (PDI) for the Content Information • Dissemination Information Package • Includes part or all of one or more Archival Information Packages • Sent to a Consumer by the OAIS Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Figure 4-1: OAIS Functional Entities (page 4-1) Preservation Planning P R O D U C E R C O N S U M E R Descriptive Information Descriptive Information Data Management Access queries Ingest SIP results orders Archival Storage AIP AIP DIP Administration M A N A G E M E N T Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
OAIS Functional Entities • Ingest: Accepts Submission Information Packages (SIPs) from Producers, prepare contents for storage and management. • Archival Storage: Storage, maintenance and retrieval of Archival Information Packages • Data Management: Populating, maintaining, and accessing both descriptive information and internal archive administrative data. • Access: Supports consumers in determining the existence, description, location and availability of information; allows consumers to request and receive information products Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
OAIS Functional Entities • Administration: Manages the overall operation of the archive system • Preservation Planning: Monitors the environment of the OAIS and provides recommendations to ensure that the information stored in the OAIS remain accessible to the Designated User Community over the long term Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
OAIS Responsibilities • Negotiates and accepts Information from information producers • Obtains sufficient control to ensure long-term preservation • Determines which communities (designated) need to be able to understand the preserved information • Ensures the information to be preserved is independently understandable to the Designated Communities • Follows documented policies and procedures which ensure the information is preserved against all reasonable contingencies • Makes the preserved information available to the Designated Communities in forms understandable to those communities Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Interoperability • Motivation • Common finding aids • Common Package Descriptor schema for access • Common DIP schema for dissemination • Common SIP schema for submission to different archives • Cost reduction through increasing the uniformity of user interactions • Categories of Interoperability • Independent, Federated, Shared: Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Reference Model Summary • Reference model is to be applicable to all digital archives, and their Producers and Consumers • Identifies a minimum set of responsibilities for an archive to claim it is an OAIS • Establishes common terms and concepts for comparing implementations, but does not specify an implementation • Provides detailed models of both archival functions and archival information • Discusses OAIS information migration and interoperability among OAISs Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Follow-on Activities • Follow-on activities coordinated by Research Libraries Group(RLG) • OAIS implementation efforts and issues page • Digital Repository Certification Task Force • RLG and the National Archives and Records Administration (NARA) • http://www.rlg.org/ Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
ISO 14721:2003 - OAIS Status and examples Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Reference Model Status • Already widely adopted as starting point in digital preservation • Digital libraries (e.g., Netherlands National Library, KB) • Traditional archives (e.g., US National Archives) • Commercial Organizations (e.g., Aerospace Industries Association preservation working team) • Scientific data centers (e.g., NASA National Space Science Data Center) Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Selected OAIS Usage Examples • National Library of Australia • Digital preservation policy • Royal Library of the Netherlands (KB) • Multiple digital preservation projects using OAIS • British National Library • Digital Preservation Strategy • US Library of Congress • Research Library Group and OnLine Computer Library Center • International, not for profit origination of libraries. • Promotes OAIS to it’s member libraries Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Selected OAIS Usage Examples-2 • InterPARES • Body of National Archives from many countries • OAIS as a starting point for archives modeling • France ARISTOTE • digital information, including libraries and Dept of Justice. • http://www.aristote.asso.fr/ (in french) • “astonishing unifying role” from OAIS reference model • US National Archives and Records Administration with San Diego Super Computer Center • “Use of OAIS RM saved several weeks of effort in specification” Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
Selected OAIS Usage Examples-3 • System for Preservation and Access to Data and Information (SIPAD) • French space agency plasma physics archive • US National Space Science Data Center (NSSDC) • US National Snow and Ice Data Center (NSIDC) • US National Oceanographic Data Center (NODC) Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
National Space Science Data Center (NSSDC) • NSSDC was the motivation for the OAIS model through the CCSDS. • The center is recasting it’s systems to align with the RM • Better separation of the functionality described in OAIS is anticipated to aid in maintaining the systems • RM helps to focus on completeness of existing system • Emphasis on preservation components, migration efficiency • Emphasis on finding aids, critical metadata Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
US National Oceanographic Data Center (NODC) • One of three environmental data centers administered by NOAA • Mapping of procedures and systems to RM helps clarify the roles and components in the existing NODC and to identify what is missing. • Need better submission agreements • Need more detailed preservation information Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia
National Snow and Ice Data Center (NSIDC) • NSIDC major programs are funded by NASA, NOAA, NSF. • OAIS RM form necessary basis for world-class archive. • OAIS RM is not sufficient. Need domain specific standards for: • To understand what information must be preserved • To understand proper and complete descriptive information (metadata standards) • Use “Global Change Science Requirements for Long Term Archiving” report [USGCRP 1999] as domain aid. Richard Ullman / 18th APAN, eScience Workshop, Cairns Austrailia