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Interpretation of the OAIS Model. Derek Sergeant. http://www.leeds.ac.uk/camileon/. Overview of the OAIS Model. In order to become familiar with the OAIS Reference Model When Cedars staff first encountered the model it took them several months to start grasping it
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Interpretation of the OAIS Model Derek Sergeant http://www.leeds.ac.uk/camileon/
Overview of the OAIS Model • In order to become familiar with the OAIS Reference Model • When Cedars staff first encountered the model it took them several months to start grasping it • Re-iterate some of the things already said
Overview of the OAIS Model • Specific vocabulary for Digital Preservation practioners • Specific advice on how to sub-divide a complex task • Provides logic and structure to allow the digital holdings to be visualised and processed
Overview of the OAIS Model • Much of the OAIS reference model does not need to be understood by the majority of people working in digital preservation • Some detail is only necessary to implement a solution (the low - level understanding)
Key concepts of the OAIS Model Producer OAIS Consumer Management
Key concepts of the OAIS Model • The Producer creates and delivers the digital objects which go into the OAIS • The Consumer asks for and receives digital objects from the OAIS • The Management deals with high level OAIS policy and monitors the OAIS
Key concepts of the OAIS Model • The OAIS receives the digital objects from the producer, archives them, and supplies them to the consumer.
Key concepts of the OAIS Model Producer OAIS Consumer SIPs DIPs AIPs Management
Key concepts of the OAIS Model • There are three basic types of Information Package • The Producer and the OAIS communicate with Submission IPs • The OAIS and the Consumer communicate with Dissemination IPs • The OAIS preserves Archive IPs
Content Information PDI Key concepts of the OAIS Model SIPs AIPs DIPs
Key concepts of the OAIS Model • Archival Information Packages contain both Content Information and Preservation Description Information • Content Information is the digital object that you need to preserve • PDI is description and information to explain what the Content actually is
Content Data Object RI Key concepts of the OAIS Model Content Information PDI AIP
Key concepts of the OAIS Model • The Content Information part of an AIP contains (very tightly coupled) the actual data object and the Representation Information that makes the object meaningful
Key concepts of the OAIS Model Content Data Object RI Intellectual Content (genuine information) = +
Key concepts of the OAIS Model • Long Term • (The Representation Information needs to keep the Content Data understandable in the Long Term) • The knowledge base of the designated community (and the archive) needs to be monitored in the Long Term
Key concepts of the OAIS Model Preservation Planning Data Management Producer Consumer Ingest Access Archival Storage Administration Management
Key concepts of the OAIS Model • Ingest gets digital objects from the Producer into the OAIS • Access passes digital objects to the Consumer • Data Management keeps track of the OAIS holdings • Archival Storage preserves AIPs in the Long Term
The Scenario • The Library that I work for has realised that over the past five years we are getting an increasing number of items that are digital • At the last University Senate meeting the Pro-Vice Chancellor for Information Technology declared that we would keep these and make them available
The Scenario • In order to do this it was realised that we need to develop a computer system capable of storing these electronic objects in a convenient form (to us) • Making them available should be just a case of duplicating the storage copy and allowing a library user to download the object
The Scenario • At the moment the digital objects that we have consist of • CD Rom supplements that arrive with a conventional book • Electronic thesis from Postgrad Computing • e-journal subscriptions
The Scenario • Upon investigation, we found a Reference Model that describes exactly what we need to do in order to preserve and make available all of our digital objects • The OAIS Reference Model
Interpreting the OAIS Model • Given that we have established a need to preserve the digital objects from our library, and that we shall be archiving them ourselves - in a newly formed library centre for preservation of electronic holdings • We revisit the basic OAIS diagram
Basic OAIS Relationships Producer OAIS Consumer Management
Interpreting the OAIS Model • Identifying the Producers: • due to the number of types and sources of digital objects there are many • e-journal publishers • CD Rom book supplement publishers • Other Departments (e-thesis) • Are there emerging trends - new Producers in the future
Interpreting the OAIS Model • Identifying the Consumers: • We inherit the same Consumers as the library • University students • University staff/researchers • Are there going to be new Consumer groups in the future?
Interpreting the OAIS Model • Identifying the Management: • Looking at the OAIS Model, we determine the roles of Management: • Long term equipment planning • Review of OAIS performance • Ratify pricing policy • Relationship development • Producer OAIS Consumer • Promote OAIS uptake • (within spheres of funding)
Interpreting the OAIS Model • Some of the roles of Management are very close to the current roles of the library management • There are no existing people that already perform the other roles • We will form a new Management group with some existing library management and other senior university strategy managers
Interpreting the OAIS Model • Identify the OAIS: • Since we are intending to preserve our digital objects ourselves, we provide the role of the OAIS • Both the Archival store and the administration
Interpreting the OAIS Model • Identify the archive holdings: • Both present holdings and future holdings • Present: • e-thesis • CD Rom book supplements • (2 e-journal subscriptions) • Future: • more internal publications • more e-journals
Structural Components of an AIP Content Information Content Data Object Representation Information Preservation Description Information AIP
Interpreting the OAIS Model • We do not have all of the components that are needed for an AIP • In the beginning, we have the Content Data Object for everything • For our e-thesis objects we also have a small amount of PDI
Lesson from the Cedars project • Determine the Significant Properties for the digital objects • This should be done as early as possible • Significant Properties are those attributes of an object that constitute the complete (for the intended Consumer) intellectual content of that object
Lesson from the Cedars project • I.e. Significant Properties for an e-thesis • The complete text, including divisions into chapters and sections • The layout and style - particular fonts and spacing are essential • Diagrams • (perhaps web adverts are not Significant for our e-journals)
Interpreting the OAIS Model • We have now established who we are working with • We have also established what data objects there are • We have moved into OAIS vocabulary • Examples of old vocabulary • Publishers, Readers • Electronic records
Functional Entities Diagram Preservation Planning Data Management Producer Consumer Ingest Access Archival Storage Administration Management
Interpreting the OAIS Model • Ingest • Establish agreements with Producers • Record assumptions about Producer and our (the OAIS) knowledge base • Take the digital data (SIPs) • Process the SIPs into AIPs • Record any current software dependencies to use the Content Data Object
Interpreting the OAIS Model • Archival Storage • Put the AIPs into Archival Storage from Ingest • Update the Data Management database to keep track of the OAIS holdings • NB: The Archival Storage system that we procure will be capable of storing and retrieving an AIP without loss • Storage, maintenance, retieval of AIPs
Interpreting the OAIS Model • Data Management • As well as keeping track of the AIPs currently in Archival Storage this entity produces Discovery Information • These can be passed to the Consumer to allow them to choose suitable AIPs for viewing
Interpreting the OAIS Model • Access • This provides support for the Consumers • It delivers DIPs (in an appropriate form for the particular Consumer)
Interpreting the OAIS Model • Administration • Overall operational control of the OAIS • Records and makes submission agreements (with Producers) • Records and implements archiving standards and policies
Interpreting the OAIS Model • Preservation Planning • Monitors the environment of the OAIS • Ensures that AIPs remain accessible • I.e. remain understandable to current Consumers • Develops templates for SIPs and DIPs and other assistance for working with Producers and Consumers
Responsibilities of an OAIS • Negotiate and accept information from Producers • Determine which community should become the Designated Community • Ensure that Information Packages are independently understandable • Ensure IPs are preserved • Make preserved IPs available
Organisational views • Establishing your Designated Community • The people who you service by preserving information for them • Determining the knowledge base of the Designated Community and monitoring changes to this knowledge base
Organisational views • The Perspective of Preservation • Long Term • To do a preservation job which takes into account • Changing technology • Changing user community
Organisational views • Deciding whether Digital Objects need to be transformed (migrated) • If they do, ensuring that nothing significant to future Consumers is lost • Are there alternatives to transforming • Source code for original software • Emulation
Organisational views • Archive Interoperability • The drivers for interoperability come from: • The Consumers • The Producers • The Management
Organisational views • Four basic models for interoperating in the OAIS Reference Model • Independent - no interoperating • Co-operating - common producers, common dissemination standards • Federated - the most interoperating • Shared Resource - reduce costs by sharing equipment
Organisational views • Federated archives • Central site? • Distributed Finding Aids • Distributed Access Aids • Issues: • Unique AIP Names - hierarchical namescheme • Duplicate AIPs • Management - level of autonomy
Site B Site A Site C Federated archives : Cedars