OAIS, Designated Communities & Metadata Jerome McDonough Graduate School of Library & Information Science University of Illinois Urbana-Champaign

A few relevant quotes “An OAIS is an archive, consisting of an organization of people and systems, that has accepted the responsibility to preserve information and make it available for a Designated Community.” “The degree to which Content Information and its associated PDI conveys information to a Designated Community is, in general, quite subjective. Nevertheless, it is essential that an archive make this determination in order to maximize information preservation. Digital Content Information and PDI need adequate Representation Information to be Independently Understandable to the Designated Community.”

A few relevant quotes “Since a key purpose of an OAIS is to preserve information for a Designated Community, the OAIS must understand the Knowledge Base of its Designated Community to understand the minimum Representation Information that must be maintained. The OAIS should then make a decision between maintaining the minimum Representation Information needed for its Designated Community, or maintaining a larger amount of Representation Information that may allow understanding by a larger Consumer community with a less specialized Knowledge Base. Over time, evolution of the Designated Community’s Knowledge Base may require updates to the Representation Information to ensure continued understanding.”

An AIP For Adventure

Knowledge Base Limits

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Knowledge Base Limits cos,0 dap csx lac (62210 add cos dc sin jmp.+4 sin,0 dap csx lac sin spa s11,add ( sub (62210 sma jmp s12 add (62210 s13,ra1 2s mul ( dac sin mul sin dac cos

The Locality of Metadata  My object is not necessarily your object.  My representation information is not necessarily your representation information. –My users may have different knowledge base than your users. –My users may have different uses for the data than your users.  My representation information today is not necessarily my representation information tomorrow.  My context information is not necessarily your context information.

The Complexity of Metadata  Representation information is not just standards documents.  Context information is not just data; in some cases it may not even be digital information.  Provenance information is not just PREMIS.  Fixity information is not just a checksum.  Reference information is not just an identifier (with a tip of the hat to John Kunze).

The Invisibility of Metadata

The Replication of Metadata  UIUC has 326 video games listed in its catalog. The Library of Congress has more than twice as many, with obvious duplication across our collections.  How many games are coded in the C language? And will every AIP for all of those games have its own copy of the C language specification? Will each institution maintain its own copy?  The GDFR may record holdings of who owns certain pieces of representation information, but who takes responsibility?

The Variability of Metadata  Structural Metadata Specs I have Known: –TEI, MOA2, METS, FOXML, MPEG21, XFDU, OAI-ORE, MXF, AAF, SMIL, HyTime, ARC, IMS-CP, SCORM, BagIt  Descriptive Specs I have Known: –MARC, Dublin Core, MODS, MADS, PBCore, IEEE LOM, EAD, P/Meta, CDWA, CSDGM, DDI, VRA Core, Darwin Core, Onix, Ecological Metadata Language  We will never all use the same metadata standard. We need to stop thinking about interoperability as a problem of adopting a single standard, and start thinking about it as a problem of translation.

The Variability of Metadata