Use Cases for Persistent Identifiers

1
Use Cases for Persistent Identifiers

• Charles Duncan
• Intrallect Ltd
• C.Duncan_at_intrallect.com

2
Confession

• I dont know much about identifiers
• I do know what I could do with them
• Two communities
• Those who want to define the functional
  specifications of persistent identifiers and
  their resolvers
• Those who dont care about that, but want to do
  things that are only possible if identifiers work
  in the background

3
Persistent Identifiers

• Why?
• Benefits
• To the owner
• To others
• How?
• Technologies
• Processes

4
Imagine

• You have just been asked to create a new medical
  course (Brain Surgery 101)
• A colleague in another university passes you the
  identifier of a reading list she has used
• You locate the list and find a useful learning
  object
• You use a web service to find the most current
  version of the learning object
• You use another web service to search for every
  course in which that learning object is used
• You use another web service to locate secondary
  metadata (reviews, comments, annotations, usage
  statistics) for the object and the courses
• You use another web service to differentiate the
  right (terms and conditions of use) of the
  courses and all their components
• You build a course based on high-quality,
  well-used, elements of different courses which
  are free and whose use is not time-limited,
  adding your own material
• You make your own course available

5
Previous work

• ERPANet Persistent identifiers
• Electronic Resource Preservation and Access
  Network
• Cork, 17-18th June 2004
• Surveyed identifiers and their users
• CETIS Learning object identifiers
• Centre for Educational Technology
  Interoperability Standards
• London, 21 Oct 2003
• Surveyed uses for identifiers

6
ERPANet CETIS

• Publishers
• Archives
• Libraries
• Repositories
• Mechanisms
• Persistence
• Resolvability
• Tools

• E-learning
• Self-publishing
• Repositories
• Federations of repositories
• Uses
• Format
• Actionability
• Persistence

7
Identifiers needed for

• Digital material
• E-publications
• Learning objects
• Media object
• Data
• Metadata
• Non-digital material
• Books
• Journals
• People
• Organisations
• Locations
• Events

8
Stakeholders

• Libraries
• Publishers
• Archives
• Repositories
• Object creators
• Object users

9
Just do it

• A system needs identifiers, choose one, and make
  it work
• A community needs identifiers
• Many independent decisions-makers
• Many proprietary and non-proprietary systems
• Some degree of local autonomy needed
• How are decisions reached
• How are processes standardised
• Lessons from ISBN?

10
CETIS Metadata SIG list

• Do I need identifiers for both objects and
  metadata in my repository
• It depends on what you want to use them for
• You shouldnt need to worry too much,
  appropriate identifiers should be generated
  automatically by your repository

11
Focus on learning objects

• Is a learning object complicated?
• Granularity
• Versions
• Relating metadata to entities
• Relating entities to entities
• Dynamic entities
• Complications similar to scientific data

12
Create and Deposit
Metadata Entity-identifier rdn.ac.uk/z-67890
Metadata-identifier rdn.ac.uk/z-meta-1234
REPOSITORY Z
Metadata
rdn.ac.uk
13
New version
Metadata Entity-identifier rdn.ac.uk/z-62847
Metadata-identifier rdn.ac.uk/z-meta-1367 Relat
ion-identifier isVersionOf rdn.ac.uk/z-67890
REPOSITORY Z
Metadata
Metadata
Metadata Entity-identifier rdn.ac.uk/z-67890
Metadata-identifier rdn.ac.uk/z-meta-1234 Relat
ion-identifier hasVersion rdn.ac.uk/z-62847
rdn.ac.uk
14
Duplicate in another repository
REPOSITORY Z
rdn.ac.uk
REPOSITORY X
Metadata
Metadata Entity-identifier rdn.ac.uk/z-67890
Metadata-identifier bath.ac.uk/z-meta-set23
bath.ac.uk
15
New entry in metadata catalogue
REPOSITORY Z
Metadata Entity-identifier rdn.ac.uk/z-67890
Metadata-identifier ltsn.ac.uk/217461
rdn.ac.uk
CATALOGUE A
Metadata
ltsn.ac.uk
16
Aggregate and store
Metadata Entity-identifier rdn.ac.uk/z-67890
Metadata-identifier gla.ac.uk/ce.311.m
Relation-identifier ispartof gla.ac.uk/ab.123.x
REPOSITORY Z
Metadata
Metadata Entity-identifier gla.ac.uk/ab.123.x
Metadata-identifier gla.ac.uk/cf.657.m
Relation-identifier haspart rdn.ac.uk/z-67890
rdn.ac.uk
REPOSITORY V
Metadata
gla.ac.uk
17
Move aggregation - disaggregate
REPOSITORY Z
Metadata
Metadata Entity-identifier gla.ac.uk/ab.123.x
Metadata-identifier rdn.ac.uk/z-meta-3999
Relation-identifier haspart rdn.ac.uk/z-67890
Metadata
REPOSITORY V
rdn.ac.uk
gla.ac.uk
18
Multiple metadata for one LO
REPOSITORY Z
Metadata Entity-identifier rdn.ac.uk/z-67890
Metadata-identifier ltsn.ac.uk/890
rdn.ac.uk
Metadata Entity-identifier rdn.ac.uk/z-67890
Metadata-identifier ltsn.ac.uk/891
CATALOGUE A
Metadata
Metadata
ltsn.ac.uk
Grant Cocks, Simulacra
19
Multiple resolutions in one LO
Metadata Entity-identifier rdn.ac.uk/z-67890
Metadata-identifier rdn.ac.uk/z-meta-1234
location resolution-low.avi resolution-medium.av
i resolution-high.avi
REPOSITORY Z
Metadata
rdn.ac.uk
Gayle Calverley, U of Manchester
20
Metadata harvesting
The HUB
Metadata
Metadata
Metadata
Some duplicate objects but not duplicate
metadata records different descriptions
Metadata
Metadata
Metadata
Metadata
Metadata
Metadata
Metadata
OAI-PMH
Metadata
ltsn.ac.uk
REPOSITORY Z
REPOSITORY Z
REPOSITORY X
ed.ac.uk
rdn.ac.uk
bath.ac.uk
Phil Barker, CETIS
21
Multilingual, multibrand, multiversion
Preferences
Metadata
Metadata
Metadata
Metadata
Searches based on Object identifier Brand
style Langauge (LIP)
Metadata
Brand Style
Metadata
Metadata
Metadata
Metadata
Metadata
Metadata
REPOSITORY X
REPOSITORY Z
REPOSITORY Z
c.com
b.com
a.com
Dan Rehak, Carnegie-Mellon
22
Issues
ISBN
ISSN
PURL
URN
OpenURL

• Dont define the solution until you have defined
  the problem
• Defining processes for using identifiers is
  as/more important than choosing identifiers
• Many, diverse publishers
• Cost/effort at point of issue
• What needs an identifier (ephemeral permanent)?
• Properties of identifiers (Uniqueness,
  Persistence, Action)
• Automatically generated when needed
• Services built on use of identifiers
• Does it matter which identifier?

Handle
URI
DOI
POI
ARK