PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Preservation Metadata:

The PREMIS ExperiencePriscilla Caplan

Florida Center for Library Automation (FCLA)

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

The Mission

• Build on the first OCLC/RLG Working Group and A Metadata Framework to Support the Preservation of Digital Objects

• Define an implementable set of core preservation metadata elements

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

OAIS Information Model

Content InformationPreservation DescriptiveInformation

Contentdata

object

RepresentationInformation

Context Info

Reference Info

Provenance Info

Fixity Info

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

What is Implementable?

• As rigorous as possible• As much explanation as possible• Implementation neutral -- “This is

what you have to know”• Values can be automatically

supplied and processed -- no lengthy textual descriptions

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

What is Core?

What most working preservation repositoriesare likely to need to knowin order to support the long-term Viability,

Renderability, Understandability, Authenticity and Identity

of archived objects.

(Maybe.)

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

PREMIS Data Model

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Types of Objects

A bitstream is data within a file, that has common attributes for preservation purposes,that can not be transformed into a stand-alone file without the addition of file structureand/or reformatting.

A filestream is a contiguous bitstream within a file that can be transformed into a stand-alone file conforming to some file format without adding any additional information.

A file is a named ordered sequence of bytes known by an operating system, accessible byapplications, that contains zero or more bytes, has access permissions and for which filesystems store statistics such as size and last modification date. A file has a file format.

A representation is the set of files, including structural metadata, needed to provide acomplete and reasonable rendition of an intellectual entity.

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

From the FrameworkNAME: Global identificationDEFINITION: Uniquely identifies the Content Data Object and its associated metadata

(Archival Information Package) to systems external to the Archive in which it isstored

EXAMPLE: ISBN, persistent URLSub-elements:NAME: Value

DEFINITION: Value of the Global Identification used to identify the AIPEXAMPLE: PURL: http://purl.oclc.org/file.pdf

NAME: Construction methodDEFINITION: Description of the means by which the Global Identification is

created and assignedEXAMPLE: Archival Information Package is registered with the OCLC PURL

service upon ingest into the Archive.NAME: Responsible agency

DEFINITION: Entity responsible for assigning and maintaining the GlobalIdentification

EXAMPLE: OCLC PURL Service

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

From the Data Dictionary

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Semantic Units Pertaining to OBJECTS

• objectIdentifier• contentLocation• originalName• preservationLevel• objectCharacteristics• environment

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

objectCharacteristics

• compositionlevel• fixity• size• format• inhibitors• significantProperties • creatingApplication

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Composition Level

.XML

Foo.PDF

.XML

Foo.tar

Foo.tgz

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Format

• What types of objects have format?• Is there a usable authority list of

formats?• Is there a difference between a

format and a profile?• What’s a format anyway?• What if there are format registries?

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

What is a format?

FILE TYPE

• XML document• XMX schema

(report.xsd)• document

conforming to report.xsd

FORMAT

• XML• XML or XSD?

• XML or REPORT?

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

The evolution of a semantic unit

• Format– formatValue– formatScheme

• Format– formatName– formatScheme

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Evolution (2)

• formatName– formatNameValue– formatVersion

• formatRegistry– formatRegistryEntry– formatRegistryKey

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Evolution(3)

• formatName– formatNameValue– formatVersion

• formatRegistry– formatRegistryIdentifier

• formatRegistryIdentifierScheme• formatRegistryIdentifierValue

– formatRegistryName– formatRegistryEntry

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Evolution (4)

• Format (Required, not repeatable)– formatName (Optional, repeatable)

• formatNameValue• formatNameVersion• formatNameRole

– formatRegistry (optional, repeatable)• formatRegistryIdentifier• formatRegistryName• formatRegistryEntry• formatRegistryRole

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

PREMIS Format Entry• Format (Required, Not Repeatable)

– formatName (Optional, Not repeatable)• formatNameValue• formatVersion

– formatRegistry (Optional, Repeatable)• formatRegistryName• formatRegistryKey• formatRegistryRole

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Environment environmentCharacteristic environmentPurpose environmentDescription dependencies software

swName swVersion swType additionalReq swDependency

hardware hwName hwVersion hwType additionalReq

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Events

• eventIdentifier– eventIdentifierScheme– eventIdentifierValue

• eventType• eventOutcome• eventOutcomeDetail• eventDetail• eventDateTime

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Agents

• agentIdentifier– agentIdentifierScheme– agentIdentifierValue

• agentName

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Relationships

• relationshipType• relatedIdentifier

– relatedIdentifierType– relatedIdentifierValue

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Rights

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Metadata Best Practices

• Have a rigorous data model and relate metadata clearly to appropriate objects

• Store metadata in database and also with content data object

• Use METS, Z39.87• Store complete metadata for all

versions of objects

PRESERVATION METADATA: IMPLEMENTATION STRATEGIES

Deliverables

• Final report– Data Dictionary– Narrative explanation– Data model– Glossary

• Incorporation into METS schema• Proposal for test bed & exchange