Mark Evans, Tessella Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013 PREMIS Practical Strategies For Preservation Metadata

Contents PREMIS Basics PREMIS - Conformance PREMIS - A practical approach Where next? Useful resources Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

Different Types of Metadata? Descriptive –supports identification and discovery of a resource Administrative –supports the management and tracking of a resource Structural –defines the arrangement and composition of a resource Preservation –supports activities intended to ensure the long term usability of a resource Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

What is PREMIS? PREservation Metadata: Implementation Strategies PREMIS is an Information Model: –Focus is on the preservation of digital objects –“The information a repository uses to support the digital preservation process” –“Things that most working preservation repositories need to know to support digital preservation functions” –Data dictionary defines a set of semantic units Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

What is Out of Scope in PREMIS? Descriptive metadata –Many existing standards support this File Format specific metadata –Metadata that pertains to only one file format or class of formats Implementation metadata –Metadata that describes specific policies and practices of an individual repository Detailed media and hardware information –Left to other communities to define –Technical environment metadata is in scope Image taken from “Understanding PREMIS”; Caplan, Library of Congress, 2009 Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics: Usage Repository Design –Provides guidelines on what information should be obtained and maintained by a preservation repository Repository evaluation –Provides a checklist to determine effective preservation management of digital objects Exchange of objects between repositories –Provides a common set of data elements that can be understood by the provider and consumer repositories Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics - Always had intellectual entities Collection Sub-Collection Record Series Item Structural metadata Descriptive metadata Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics – Now We Have Digital Objects Technical Metadata Fixity Checksum Size Format Version Environment Hardware Operating system Rendering software Embedded images Media properties Type, age etc Digital provenance Authenticity Digital signatures Inhibitors Significant Properties Technical metadata Records of XYZ Committee 1995 – Word Perfect 2000 – Word – Word – Word 2010 Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics - And need to do more things… Records of XYZ Committee 1995 – Word Perfect 2000 – Word – Word – Word 2010 Original Representation 1995 – PDF/A 2000 – PDF/A 2005 – PDF/A 2010 – PDF/A Migrated Representation Format Migration Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics - 3 Types of Digital Object Representation – Set of digital objects needed to render an Intellectual Entity 1995 – Word Perfect Chapter 2.doc Chapter 3.doc Chapter 4.doc Chapter 1.doc File – A named and ordered sequence of bytes that is known by an operating system Bitstream– is contiguous or non-contiguous data within a file that has meaningful common properties for preservation purposes. Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics – Data Model Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013 Rights Assertion of rights and permissions Events Actions that involve an Object and an agent known to the system Agents People, organizations or software Objects Units of information in digital form Intellectual Entity Content that can be described as a unit

PREMIS Basics – Semantic Units Semantic Units: –Convey a piece of information / knowledge –Do not specify how they should be represented in a particular system (as opposed to metadata elements) –Should be exportable to other systems –May have a direct mapping to metadata elements in an XML schema Containers and sub units –Some semantic units are defined as containers –Facilitiates a hierarchical structure to the data dictionary –Extension containers are allowed Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics - Objects Rights Events AgentsObjects Intellectual Entity Identifier Category (Representation, File, Bitsteam) Preservation level Significant properties: –Type (e.g., page count) –Value (e.g., 7) Characteristics: –Fixity –Size (bytes) –Format (Designation, Registry, Note) –Creating application –Inhibitors Original name Storage Environment: –… –Software –Hardware –… Signature Information Relationship Linked events Linked intellectual entity Linked rights statement Semantic Units Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics - Events Semantic Units: Identifier Type Date Time Detail Outcome Information Linking Agent Identifier Linking Object Identifier Rights Events AgentsObjects Intellectual Entity Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics - Rights Semantic Units Identifier Basis Copyright Information Licence Information Statute Information Rights granted Linking object Linking agent Rights Events AgentsObjects Intellectual Entity Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics - Agents Semantic Units Identifier Name Type Rights Events AgentsObjects Intellectual Entity Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics – Example Dictionary Entry Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Basics – Example Dictionary Entry Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Conformance To be conformant: –Implemented semantic units should have the stated definition, constraints and applicability prescribed in the Data Dictionary –If share name, must share definition –If not share name, must map definition (if mandatory) –Can be more stringent, but NOT more liberal. (Can add constraints but not remove them) –An export of semantic units must contain all mandatory elements for the entities that are supported Internal Conformance –Conformant within the repository External conformance –Repository must be able to accept / export conformant semantic units Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Conformance Not required for conformance –Support for all entity types –Use of semantic unit names internally –Use of inference or mapping There is a PREMIS XML Schema but do NOT have to use this to be CONFORMANT. –E.g. Use of PREMIS “in” METS provides some overlap –Planets data model has PREMIS extensions Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS Practicalities: e.g., SDB Pre-dates PREMIS (Representation = Manifestation) Need to respond quickly: Add extra fields to entities Need more entities: –Intellectual Entities broken down more than via cataloguing –Complex relationship with Representations –Use for automated migration and validation Don’t want to hold lots of repeated information: –Use PRONOM PUIDs so Registry implied for every Format Hold Storage separate from immutable metadata Do have option to export to PREMIS XML schema: –Make implicit information explicit Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

Example of PREMIS in SDB Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

PREMIS – Governance Model “Self-governed” by community PREMIS Editorial Committee If you get involved.. –Likely to get invited on! Does react But it is everyone’s part-time job! PREMIS 3.0: –Adds Intellectual Entity –Adds Environments –Allows for less verbosity Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

CONCLUSIONS PREMIS: –Information Model for digital preservation –Allows for implementation variations –Allows for extensions (low conformance barrier) –Reacts to community –JOIN IN! Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013

Useful Resources PREMIS specification PREMIS primer Conformance Guidance PREMIS Implementers Group (PIG) Mark Evans – Digital Preservation Boot Camp – PASIG meeting, Washington DC, 22 nd May 2013